Copyright © Future Technology Devices International Limited 1
FT201X USB I2C SLAVE IC Datasheet
Version 1.5
Document No.: FT_000627 Clearance No.: FTDI# 264
Future Technology Devices
International Ltd.
FT201X
(USB I2C SLAVE IC)
The FT201X is a USB to I2C interface
with the following advanced features:
Single chip USB to I2C slave interface.
Up to 3.4MHz, high speed mode, I2C supported
Entire USB protocol handled on the chip. No
USB specific firmware programming required.
Fully integrated 2048 byte multi-time-
programmable (MTP) memory, storing device
descriptors and CBUS I/O configuration.
Fully integrated clock generation with no
external crystal required plus optional clock
output selection enabling a glue-less interface
to external MCU or FPGA.
512 byte receive buffer and 512 byte transmit
buffer utilising buffer smoothing technology to
allow for high data throughput.
FTDI’s royalty-free Virtual Com Port (VCP) and
Direct (D2XX) drivers eliminate the
requirement for USB driver development in
most cases.
Configurable CBUS I/O pins.
Transmit and receive LED drive signals.
USB Battery Charger Detection. Allows for USB
peripheral devices to detect the presence of a
higher power source to enable improved
charging.
Device supplied pre-programmed with unique
USB serial number.
USB Power Configurations; supports bus-
powered, self-powered and bus-powered with
power switching.
Integrated +3.3V level converter for USB I/O.
True 3.3V CMOS drive output and TTL input;
Operates down to 1V8 with external pull-ups.
Tolerant of 5V input.
Configurable I/O pin output drive strength; 4
mA (min) and 16 mA (max).
Integrated power-on-reset circuit.
Fully integrated AVCC supply filtering - no
external filtering required.
+ 5V Single Supply Operation.
Internal 3V3/1V8 LDO regulators
Low operating and USB suspend current; 8mA
(active-typ) and 125uA (suspend-typ).
UHCI/OHCI/EHCI host controller compatible.
USB 2.0 Full Speed compatible.
Extended operating temperature range; -40 to
85⁰C.
Available in compact Pb-free 16 Pin SSOP and
QFN packages (both RoHS compliant).
Neither the whole nor any part of the information contained in, or the product described in this manual, may be adapted or reproduced
in any material or electronic form without the prior written consent of the copyright holder. This product and its documentation are
supplied on an as-is basis and no warranty as to their suitability for any particular purpose is either made or implied. Future Technology
Devices International Ltd will not accept any claim for damages howsoever arising as a result of use or failure of this product. Your
statutory rights are not affected. This product or any variant of it is not intended for use in any medical appliance, device or system in
which the failure of the product might reasonably be expected to result in personal injury. This document provides preliminary
information that may be subject to change without notice. No freedom to use patents or other intellectual property rights is implied by
the publication of this document. Future Technology Devices International Ltd, Unit 1, 2 Seaward Place, Centurion Business Park, Glasgow
G41 1HH United Kingdom. Scotland Registered Company Number: SC136640
Copyright © Future Technology Devices International Limited 2
FT201X USB I2C SLAVE IC Datasheet
Version 1.5
Document No.: FT_000627 Clearance No.: FTDI# 264
1 Typical Applications
Upgrading Legacy Peripherals to USB
Utilising USB to add system modularity
Incorporate USB interface to enable PC
transfers for development system
communication
Motherboard and system monitoring through
USB
USB dongle implementations for Software/
Hardware Encryption and Wireless Modules
Interfacing MCU/PLD/FPGA based designs to
add USB connectivity
USB Instrumentation
USB Industrial Control
USB Digital Camera Interface
Ability to detect dedicated charging ports for
high current charging of batteries in portable
devices
1.1 Driver Support
Royalty free VIRTUAL COM PORT
(VCP) DRIVERS for...
Windows 8 32,64-bit
Windows 7 32,64-bit
Windows Vista and Vista 64-bit
Windows XP and XP 64-bit
Windows Embedded Operating Systems
Server 2003, XP and Server 2008
Windows CE 4.2, 5.0 and 6.0
Mac OS-X
Linux 3.2 and greater
Android
Royalty free D2XX Direct Drivers
(USB Drivers + DLL S/W Interface)
Windows 8 32,64-bit
Windows 7 32,64-bit
Windows Vista and Vista 64-bit
Windows XP and XP 64-bit
Windows Embedded Operating Systems
Server 2003, XP and Server 2008
Windows CE 4.2, 5.0 and 6.0
Mac OS-X
Linux 2.6 and greater
Android
The drivers listed above are all available to download for free from FTDI website (www.ftdichip.com).
Various 3rd party drivers are also available for other operating systems - see FTDI website
(www.ftdichip.com) for details.
For driver installation, please refer to http://www.ftdichip.com/Documents/InstallGuides.htm
1.2 Part Numbers
Part Number
Package
FT201XQ-x
16 Pin QFN
FT201XS-x
16 Pin SSOP
Note: Packing codes for x is:
- R: Taped and Reel, (SSOP is 3,000pcs per reel, QFN is 5,000pcs per reel).
- U: Tube packing, 100pcs per tube (SSOP only)
- T: Tray packing, 490pcs per tray (QFN only)
For example: FT201XQ-R is 5,000pcs taped and reel packing
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FT201X USB I2C SLAVE IC Datasheet
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Document No.: FT_000627 Clearance No.: FTDI# 264
1.3 USB Compliant
The FT201X is fully compliant with the USB 2.0 specification and has been given the USB-IF Test-ID (TID)
40001460 (Rev D).
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FT201X USB I2C SLAVE IC Datasheet
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2 FT201X Block Diagram
Figure 2.1 FT201X Block Diagram
For a description of each function please refer to Section 4.
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FT201X USB I2C SLAVE IC Datasheet
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Table of Contents
1 Typical Applications ....................................................... 2
1.1 Driver Support ........................................................................... 2
1.2 Part Numbers ............................................................................. 2
1.3 USB Compliant ........................................................................... 3
2 FT201X Block Diagram .................................................. 4
3 Device Pin Out and Signal Description ........................... 7
3.1 16-LD QFN Package .................................................................. 7
3.1.1 QFN Package PinOut Description ................................................................... 7
3.2 16-LD SSOP Package ................................................................. 9
3.2.1 SSOP Package PinOut Description ................................................................. 9
3.3 CBUS Signal Options ................................................................ 11
4 Function Description ................................................... 13
4.1 Key Features ............................................................................ 13
4.2 Functional Block Descriptions .................................................. 13
5 I2C Interface Description ............................................. 15
6 Devices Characteristics and Ratings ............................ 16
6.1 Absolute Maximum Ratings ...................................................... 16
6.2 ESD and Latch-up Specifications .............................................. 16
6.3 DC Characteristics .................................................................... 17
6.4 MTP Memory Reliability Characteristics ................................... 21
6.5 Internal Clock Characteristics .................................................. 21
7 USB Power Configurations ........................................... 22
7.1 USB Bus Powered Configuration ............................................. 22
7.2 Self Powered Configuration ..................................................... 23
7.3 USB Bus Powered with Power Switching Configuration ........... 24
8 Application Examples .................................................. 25
8.1 USB to I2C Converter ................................................................ 25
8.2 USB Battery Charging Detection .............................................. 26
9 USB and I2C Interfacing .............................................. 29
9.1 Host Interface (USB) ............................................................... 29
9.1.1 VCP and D2xx Interfaces ............................................................................ 29
9.1.2 Reading and Writing Data........................................................................... 30
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FT201X USB I2C SLAVE IC Datasheet
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9.2 I2C Interface ............................................................................ 31
9.2.1 Addressing ............................................................................................... 31
9.2.2 Data Transfers .......................................................................................... 31
9.3 Other I2C Commands ............................................................... 33
10 Internal MTP Memory Configuration ............................ 35
10.1 Default Values ....................................................................... 35
10.2 Methods of Programming the MTP Memory ........................... 36
10.2.1 Programming the MTP memory over USB ..................................................... 36
10.2.2 Programming the MTP memory over I2C....................................................... 37
10.3 Memory Map .......................................................................... 37
10.4 Hardware Requirements ........................................................ 38
10.5 Protocol ................................................................................. 38
10.5.1 Address MTP memory (0x10) ...................................................................... 39
10.5.2 Write MTP memory (0x12) ......................................................................... 39
10.5.3 Read MTP memory (0x14) .......................................................................... 39
10.5.4 Examples of Writing and Reading ................................................................ 39
11 Package Parameters .................................................... 41
11.1 SSOP-16 Package Mechanical Dimensions ............................. 41
11.2 SSOP-16 Package Markings ................................................... 42
11.3 QFN-16 Package Mechanical Dimensions ............................... 43
11.4 QFN-16 Package Markings ..................................................... 44
11.5 Solder Reflow Profile ............................................................. 45
12 Contact Information .................................................... 46
Appendix A – References ................................................... 47
Document References ...................................................................... 47
Acronyms and Abbreviations ............................................................ 47
Appendix B - List of Figures and Tables ............................. 48
List of Figures .................................................................................. 48
List of Tables .................................................................................... 48
Appendix C - Revision History ............................................ 50
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3 Device Pin Out and Signal Description
3.1 16-LD QFN Package
VCCIO 1
GND
3
SCL 16
CBUS4 4
CBUS2 5
USBDP
6USBDM
7
3V3OUT
8
RESET#
9
VCC 10
CBUS1 11
CBUS0 12
GND
13
CBUS5 15
SDA 2
CBUS3 14
GND
17
Figure 3.1 QFN Schematic Symbol
3.1.1 QFN Package PinOut Description
Note: # denotes an active low signal.
Pin No.
Name
Type
Description
10
**
VCC
POWER
Input
5 V (or 3V3) supply to IC
1
VCCIO
POWER
Input
1V8 - 3V3 supply for the IO cells
8
**
3V3OUT
POWER
Output
3V3 output at 50mA. May be used to power VCCIO.
When VCC is 3V3; pin 8 is an input pin. Connect to pin
10.
3, 13
GND
POWER
Input
0V Ground input.
Table 3.1 Power and Ground
*Pin 17 is centre pad beneath the IC. Connect to GND.
** If VCC is 3V3 then 3V3OUT must also be driven with 3V3 input
Pin No.
Name
Type
Description
7
USBDM
INPUT
USB Data Signal Minus.
6
USBDP
INPUT
USB Data Signal Plus.
9
RESET#
INPUT
Reset input (active low).
Table 3.2 Common Function pins
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FT201X USB I2C SLAVE IC Datasheet
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Pin No.
Name
Type
Description
2
SDA
I/O
I2C bi-directional data line
16
SCL
Input
I2C clock input
12
CBUS0
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the
device MTP memory. See CBUS Signal Options, Table 3.7.
11
CBUS1
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the
device MTP memory. See CBUS Signal Options, Table 3.7.
5
CBUS2
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the
device MTP memory. See CBUS Signal Options, Table 3.7.
14
CBUS3
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the
device MTP memory. See CBUS Signal Options, Table 3.7.
4
CBUS4
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the
device MTP memory. See CBUS Signal Options, Table 3.7.
15
CBUS5
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the
device MTP memory. See CBUS Signal Options, Table 3.7.
Table 3.3 I2C Interface and CBUS Group (see note 1)
Notes:
1. When used in Input Mode, the input pins are pulled to VCCIO via internal 75kΩ (approx.) resistors.
These pins can be programmed to gently pull low during USB suspend (PWREN# = “1”) by setting an
option in the MTP memory.
2. Clock stretching is not supported
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FT201X USB I2C SLAVE IC Datasheet
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3.2 16-LD SSOP Package
SDA 4
GND
5
CBUS4 6
CBUS2 7
USBDP
8USBDM
9
3V3OUT
10
RESET#
11
VCC 12
GND
13
CBUS1 14
CBUS0 15
CBUS3 16
CBUS5 1
SCL 2
VCCIO 3
Figure 3.2 SSOP Schematic Symbol
3.2.1 SSOP Package PinOut Description
Note: # denotes an active low signal.
Pin No.
Name
Type
Description
12
**
VCC
POWER
Input
5 V (or 3V3) supply to IC
3
VCCIO
POWER
Input
1V8 - 3V3 supply for the IO cells
10
**
3V3OUT
POWER
Output
3V3 output at 50mA. May be used to power VCCIO.
When VCC is 3V3, pin 10 is an input pin and should be
connected to pin 12.
5, 13
GND
POWER
Input
0V Ground input.
Table 3.4 Power and Ground
** If VCC is 3V3 then 3V3OUT must also be driven with 3V3 input
Pin No.
Name
Type
Description
9
USBDM
INPUT
USB Data Signal Minus.
8
USBDP
INPUT
USB Data Signal Plus.
11
RESET#
INPUT
Reset input (active low).
Table 3.5 Common Function pins
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FT201X USB I2C SLAVE IC Datasheet
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Pin No.
Name
Type
Description
4
SDA
I/O
I2C bi-directional data line
2
SCL
Input
I2C clock input
15
CBUS0
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the
device MTP memory. See CBUS Signal Options, Table 3.7.
14
CBUS1
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the
device MTP memory. See CBUS Signal Options, Table 3.7.
7
CBUS2
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the
device MTP memory. See CBUS Signal Options, Table 3.7.
16
CBUS3
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the
device MTP memory. See CBUS Signal Options, Table 3.7.
6
CBUS4
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the
device MTP memory. See CBUS Signal Options, Table 3.7.
1
CBUS5
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the
device MTP memory. See CBUS Signal Options, Table 3.7.
Table 3.6 Interface and CBUS Group (see note 1)
Notes:
1. When used in Input Mode, the input pins are pulled to VCCIO via internal 75kΩ (approx.) resistors.
These pins can be programmed to gently pull low during USB suspend (PWREN# = “1”) by setting an
option in the MTP memory.
2. Clock stretching is not supported
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FT201X USB I2C SLAVE IC Datasheet
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3.3 CBUS Signal Options
The following options can be configured on the CBUS I/O pins. CBUS signal options are common to both
package versions of the FT201X. These options can be configured in the internal MTP memory using the
software utility FT_PROG, which can be downloaded from the FTDI Utilities (www.ftdichip.com). The
default configuration is described in Section 9.
CBUS
Signal
Option
Available On CBUS Pin
Description
TRI-STATE
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
IO Pad is tri-stated
DRIVE 1
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
Output a constant 1
DRIVE 0
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
Output a constant 0
PWREN#
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
Output is low after the device has been configured by
USB, then high during USB suspend mode. This output
can be used to control power to an external logic P-
Channel logic level MOSFET switch. Enable the interface
pull-down option when using the PWREN# in this way.
SLEEP#
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
Goes low during USB suspend mode. Typically used to
power down an external logic.
CLK24MHz
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
24 MHz Clock output.*
CLK12MHz
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
12 MHz Clock output.*
CLK6MHz
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
6 MHz Clock output.*
GPIO
CBUS0, CBUS1, CBUS2, CBUS3,
CBUS bit bang mode option. Allows up to 4 of the CBUS
pins to be used as general purpose I/O. Configured
individually for CBUS0, CBUS1, CBUS2 and CBUS3 in the
internal MTP memory. A separate application note,
AN232R-01, available from FTDI website
(www.ftdichip.com) describes in more detail how to use
CBUS bit bang mode.
BCD Charger
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
Battery charge Detect, indicates when the device is
connected to a dedicated battery charger host. Active
high output.
BCD
Charger#
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
Inverse of BCD Charger (open drain)
BitBang_WR#
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
Synchronous and asynchronous bit bang mode WR#
strobe output.
BitBang_RD#
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
Synchronous and asynchronous bit bang mode RD#
strobe output.
I2C_TXE#
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
Transmit buffer empty, used to indicate to I2C master
device status of the FT201EX transmit buffer
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CBUS
Signal
Option
Available On CBUS Pin
Description
I2C_RXF#
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
Receive buffer full, used to indicate to I2C master device
status of FT201EX receive buffer
VBUS Sense
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
Input to detect when VBUS is present.
Time Stamp
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
Toggle signal which changes state each time a USB SOF
is received
Keep_Awake#
CBUS0, CBUS1, CBUS2, CBUS3, CBUS4,
CBUS5
Prevents the device from entering suspend state when
unplugged. May be used if programming the MTP
memory over I2C
Table 3.7 CBUS Configuration Control
*When in USB suspend mode the outputs clocks are also suspended.
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4 Function Description
The FT201X is a USB to I2C interface device which simplifies USB implementations and reduces external
component count by fully integrating into the device an EEPROM, and a clock circuit which requires no
external crystal. It has been designed to operate efficiently with USB host controllers by using as little
bandwidth as possible when compared to the total USB bandwidth available.
4.1 Key Features
Functional Integration. Fully integrated MTP memory, clock generation, AVCC filtering, Power-On-
Reset (POR) and LDO regulators.
Configurable CBUS I/O Pin Options. The fully integrated MTP memory allows configuration of the
Control Bus (CBUS) functionality and drive strength selection. There are 6 configurable CBUS I/O pins.
These configurable options are defined in section 3.3.
The device is shipped with the most commonly used pin definitions pre-programmed - see Section 9 for
details.
Asynchronous Bit Bang Mode with RD# and WR# Strobes. The FT201X supports FTDI’s previous
chip generation bit-bang mode. In bit-bang mode, the 2 I2C lines can be switched from the regular
interface mode to a 2-bit general purpose I/O port. Data packets can be sent to the device and they will
be sequentially sent to the interface at a rate controlled by an internal timer (equivalent to the baud rate
pre-scalar). In the FT201X device this mode has been enhanced by outputting the internal RD# and WR#
strobes signals which can be used to allow external logic to be clocked by accesses to the bit-bang I/O
bus. This option will be described more fully in a separate application note available from FTDI website
(www.ftdichip.com).
Synchronous Bit Bang Mode. The FT201X supports synchronous bit bang mode. This mode differs from
asynchronous bit bang mode in that the interface pins are only read when the device is written to. This
makes it easier for the controlling program to measure the response to an output stimulus as the data
returned is synchronous to the output data. An application note, AN232R-01, available from FTDI website
(www.ftdichip.com) describes this feature.
Source Power and Power Consumption. The FT201X is capable of operating at a voltage supply
between +3.3V and +5.25V with a nominal operational mode current of 8mA and a nominal USB suspend
mode current of 125µA. This allows greater margin for peripheral designs to meet the USB suspend mode
current limit of 2.5mA. An integrated level converter within the I2C interface allows the FT201X to
interface to UART logic running at +1.8V to +3.3V (5V tolerant).
4.2 Functional Block Descriptions
The following paragraphs detail each function within the FT201X. Please refer to the block diagram shown
in Figure 2.1
Internal MTP Memory. The internal MTP memory in the FT201X is used to store USB Vendor ID (VID),
Product ID (PID), device serial number, product description string and various other USB configuration
descriptors. The internal MTP memory is also used to configure the CBUS pin functions. The FT201X is
supplied with the internal MTP memory pre-programmed as described in Section 9. A user area of the
internal MTP memory is available to system designers to allow storing of additional data from the user
application over USB. The internal MTP memory descriptors can be programmed in circuit, over USB
without any additional voltage requirement. The descriptors can be programmed using the FTDI utility
software called FT_PROG, which can be downloaded from FTDI Utilities on the FTDI website
(www.ftdichip.com). Additionally the MTP memory can be configured over the I2C interface.
+1.8V LDO Regulator. The +1.8V LDO regulator generates the +1.8V reference voltage for driving the
internal core of the IC.
+3.3V LDO Regulator. The +3.3V LDO regulator generates the +3.3V reference voltage for driving the
USB transceiver cell output buffers. It requires an external decoupling capacitor to be attached to the
3V3OUT regulator output pin. It also provides +3.3V power to the 1.5kΩ internal pull up resistor on
USBDP. The main function of the LDO is to power the USB Transceiver and the Reset Generator Cells
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rather than to power external logic. However, it can be used to supply external circuitry requiring a
+3.3V nominal supply with a maximum current of 50mA.
USB Transceiver. The USB Transceiver Cell provides the USB 1.1 / USB 2.0 full-speed physical interface
to the USB cable. The output drivers provide +3.3V level slew rate control signalling, whilst a differential
input receiver and two single ended input receivers provide USB data in, Single-Ended-0 (SE0) and USB
reset detection conditions respectfully. This function also incorporates a 1.5kΩ pull up resistor on USBDP.
The block also detects when connected to a USB power supply which will not enumerate the device but
still supply power and may be used for battery charging.
USB DPLL. The USB DPLL cell locks on to the incoming NRZI USB data and generates recovered clock
and data signals for the Serial Interface Engine (SIE) block.
Internal 12MHz Oscillator - The Internal 12MHz Oscillator cell generates a 12MHz reference clock. This
provides an input to the x4 Clock Multiplier function. The 12MHz Oscillator is also used as the reference
clock for the SIE, USB Protocol Engine and UART FIFO controller blocks.
Clock Multiplier / Divider. The Clock Multiplier / Divider takes the 12MHz input from the Internal
Oscillator function and generates the 48MHz, 24MHz, 12MHz and 6MHz reference clock signals. The 48Mz
clock reference is used by the USB DPLL and the Baud Rate Generator blocks.
Serial Interface Engine (SIE). The Serial Interface Engine (SIE) block performs the parallel to serial
and serial to parallel conversion of the USB data. In accordance with the USB 2.0 specification, it
performs bit stuffing/un-stuffing and CRC5/CRC16 generation. It also checks the CRC on the USB data
stream.
USB Protocol Engine. The USB Protocol Engine manages the data stream from the device USB control
endpoint. It handles the low level USB protocol requests generated by the USB host controller and the
commands for controlling the functional parameters of the I2C in accordance with the USB 2.0
specification chapter 9.
FIFO RX Buffer (512 bytes). Data sent from the USB host controller to the I2C interface via the USB
data OUT endpoint is stored in the FIFO RX (receive) buffer. Data is removed from the buffer to the I2C
transmit register under control of the I2C Controller. (Rx relative to the USB interface).
FIFO TX Buffer (512 bytes). Data from the I2C receive register is stored in the TX buffer. The USB host
controller removes data from the FIFO TX Buffer by sending a USB request for data from the device data
IN endpoint. (Tx relative to the USB interface).
I2C Controller. Module to handle the latching in and out of serial data on the I2C interface. Supports up
to 3.4MHz, High Speed Serial Mode.
RESET Generator - The integrated Reset Generator Cell provides a reliable power-on reset to the device
internal circuitry at power up. The RESET# input pin allows an external device to reset the FT201X.
RESET# can be tied to 3V3OUT.
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5 I2C Interface Description
I2C (Inter Integrated Circuit) is a multi-master serial bus invented by Philips. I2C uses two bi-directional
open-drain wires called serial data (SDA) and serial clock (SCL). Common I²C bus speeds are the 100
kbit/s standard mode (SM), 400 kbit/s fast mode (FM), 1 Mbit/s Fast mode plus (FM+), and 3.4 Mbit/s
High Speed mode (HS)
An I2C bus node can operate either as a master or a slave:
Master node – issues the clock and addresses slaves
Slave node – receives the clock line and address.
The FT201X device shall only be able to operate as a slave, but is capable of speeds up to 3.4MBit/s.
There are four potential modes of operation for a given bus device, although most devices only use a
single role and its two modes:
Master transmit – sending data to a slave
Master receive – receiving data from a slave
Slave transmit – sending data to a master
Slave receive – receiving data from the master
The master is initially in master transmit mode by sending a start bit followed by the 7-bit address of the
slave it wishes to communicate with, which is finally followed by a single bit representing whether it
wishes to write(0) to or read(1) from the slave.
If the slave exists on the bus then it will respond with an ACK bit (active low for acknowledged) for that
address. The master then continues in either transmit or receive mode (according to the read/write bit it
sent), and the slave continues in its complementary mode (receive or transmit, respectively).
The address and the data bytes are sent most significant bit first. The start bit is indicated by a high-to-
low transition of SDA with SCL high; the stop bit is indicated by a low-to-high transition of SDA with SCL
high.
If the master wishes to write to the slave then it repeatedly sends a byte with the slave sending an ACK
bit. (In this situation, the master is in master transmit mode and the slave is in slave receive mode.)
If the master wishes to read from the slave then it repeatedly receives a byte from the slave, the master
sending an ACK bit after every byte but the last one. (In this situation, the master is in master receive
mode and the slave is in slave transmit mode.)
The master then ends transmission with a stop bit, or it may send another START bit if it wishes to retain
control of the bus for another transfer (a "combined message").
I²C defines three basic types of message, each of which begins with a START and ends with a STOP:
Single message where a master writes data to a slave;
Single message where a master reads data from a slave;
Combined messages, where a master issues at least two reads and/or writes to one or more
slaves
In a combined message, each read or write begins with a START and the slave address. After the first
START, these are also called repeated START bits; repeated START bits are not preceded by STOP bits,
which is how slaves know the next transfer is part of the same message.
Please refer to the I2C specification for more information on the protocol.
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6 Devices Characteristics and Ratings
6.1 Absolute Maximum Ratings
The absolute maximum ratings for the FT201X devices are as follows. These are in accordance with the
Absolute Maximum Rating System (IEC 60134). Exceeding these may cause permanent damage to the
device.
Parameter
Value
Unit
Conditions
Storage Temperature
-65°C to 150°C
Degrees C
Floor Life (Out of Bag) At Factory Ambient
(30°C / 60% Relative Humidity)
168 Hours
(IPC/JEDEC J-
STD-033A MSL
Level 3
Compliant)*
Hours
Ambient Operating Temperature (Power
Applied)
-40°C to 85°C
Degrees C
MTTF FT201XS
TBD
Hours
MTTF FT201XQ
TBD
Hours
VCC Supply Voltage
-0.3 to +5.5
V
VCCIO IO Voltage
-0.3 to +4.0
V
DC Input Voltage – USBDP and USBDM
-0.5 to +3.63
V
DC Input Voltage – High Impedance
Bi-directional (powered from VCCIO)
-0.3 to +5.8
V
DC Output Current – Outputs
22
mA
Table 6.1 Absolute Maximum Ratings
* If devices are stored out of the packaging beyond this time limit the devices should be baked before
use. The devices should be ramped up to a temperature of +125°C and baked for up to 17 hours.
6.2 ESD and Latch-up Specifications
Description
Specification
Human Body Mode (HBM)
> ± 2kV
Machine mode (MM)
> ± 200V
Charged Device Mode (CDM)
> ± 500V
Latch-up
> ± 200mA
Table 6.2 ESD and Latch-Up Specifications
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6.3 DC Characteristics
DC Characteristics (Ambient Temperature = -40°C to +85°C)
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
VCC
VCC Operating Supply
Voltage
2.97
5
5.5
V
Normal Operation
VCC2
VCCIO Operating
Supply Voltage
1.62
---
3.63
V
Icc1
Operating Supply
Current
6.4
8
8.65
mA
Normal Operation
Icc2
Operating Supply
Current
125
μA
USB Suspend
3V3OUT
3.3v regulator output
2.97
3.3
3.63
V
VCC must be
greater than 3V3
otherwise 3V3OUT
is an input which
must be driven
with 3.3V
Table 6.3 Operating Voltage and Current
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Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
2.97
VCCIO
VCCIO
V
Ioh = -2mA
I/O Drive strength*
= 4mA
2.97
VCCIO
VCCIO
V
I/O Drive strength*
= 8mA
2.97
VCCIO
VCCIO
V
I/O Drive strength*
= 12mA
2.97
VCCIO
VCCIO
V
I/O Drive strength*
= 16mA
Vol
Output Voltage Low
0
0.4
V
Iol = +2mA
I/O Drive strength*
= 4mA
0
0.4
V
I/O Drive strength*
= 8mA
0
0.4
V
I/O Drive strength*
= 12mA
0
0.4
V
I/O Drive strength*
= 16mA
Vil
Input low Switching
Threshold
0.8
V
LVTTL
Vih
Input High Switching
Threshold
2.0
V
LVTTL
Vt
Switching Threshold
1.49
V
LVTTL
Vt-
Schmitt trigger negative
going threshold voltage
1.15
V
Vt+
Schmitt trigger positive
going threshold voltage
1.64
V
Rpu
Input pull-up resistance
40
75
190
KΩ
Vin = 0
Rpd
Input pull-down
resistance
40
75
190
KΩ
Vin =VCCIO
Iin
Input Leakage Current
-10
+/-1
10
μA
Vin = 0
Ioz
Tri-state output leakage
current
-10
+/-1
10
μA
Vin = 5.5V or 0
Table 6.4 I/O Pin Characteristics VCCIO = +3.3V (except USB PHY pins)
* The I/O drive strength and slow slew-rate are configurable in the MTP memory.
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FT201X USB I2C SLAVE IC Datasheet
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Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
2.25
VCCIO
VCCIO
V
Ioh = +/-2mA
I/O Drive strength*
= 4mA
2.25
VCCIO
VCCIO
V
I/O Drive strength*
= 8mA
2.25
VCCIO
VCCIO
V
I/O Drive strength*
= 12mA
2.25
VCCIO
VCCIO
V
I/O Drive strength*
= 16mA
Vol
Output Voltage Low
0
0.4
V
Iol = +/-2mA
I/O Drive strength*
= 4mA
0
0.4
V
I/O Drive strength*
= 8mA
0
0.4
V
I/O Drive strength*
= 12mA
0
0.4
V
I/O Drive strength*
= 16mA
Vil
Input low Switching
Threshold
0.8
V
LVTTL
Vih
Input High Switching
Threshold
0.8
V
LVTTL
Vt
Switching Threshold
1.1
V
LVTTL
Vt-
Schmitt trigger negative
going threshold voltage
0.8
V
Vt+
Schmitt trigger positive
going threshold voltage
1.2
V
Rpu
Input pull-up resistance
40
75
190
KΩ
Vin = 0
Rpd
Input pull-down
resistance
40
75
190
KΩ
Vin =VCCIO
Iin
Input Leakage Current
-10
+/-1
10
μA
Vin = 0
Ioz
Tri-state output leakage
current
-10
+/-1
10
μA
Vin = 5.5V or 0
Table 6.5 I/O Pin Characteristics VCCIO = +2.5V (except USB PHY pins)
* The I/O drive strength and slow slew-rate are configurable in the MTP memory.
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FT201X USB I2C SLAVE IC Datasheet
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Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
1.62
VCCIO
VCCIO
V
Ioh = +/-2mA
I/O Drive strength*
= 4mA
1.62
VCCIO
VCCIO
V
I/O Drive strength*
= 8mA
1.62
VCCIO
VCCIO
V
I/O Drive strength*
= 12mA
1.62
VCCIO
VCCIO
V
I/O Drive strength*
= 16mA
Vol
Output Voltage Low
0
0.4
V
Iol = +/-2mA
I/O Drive strength*
= 4mA
0
0.4
V
I/O Drive strength*
= 8mA
0
0.4
V
I/O Drive strength*
= 12mA
0
0.4
V
I/O Drive strength*
= 16mA
Vil
Input low Switching
Threshold
0.77
V
LVTTL
Vih
Input High Switching
Threshold
1.6
V
LVTTL
Vt
Switching Threshold
0.77
V
LVTTL
Vt-
Schmitt trigger negative
going threshold voltage
0.557
V
Vt+
Schmitt trigger positive
going threshold voltage
0.893
V
Rpu
Input pull-up resistance
40
75
190
KΩ
Vin = 0
Rpd
Input pull-down
resistance
40
75
190
KΩ
Vin =VCCIO
Iin
Input Leakage Current
-10
+/-1
10
μA
Vin = 0
Ioz
Tri-state output leakage
current
-10
+/-1
10
μA
Vin = 5.5V or 0
Table 6.6 I/O Pin Characteristics VCCIO = +1.8V (except USB PHY pins)
* The I/O drive strength and slow slew-rate are configurable in the MTP memory.
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FT201X USB I2C SLAVE IC Datasheet
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Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
3V3OUT-
0.2
V
Vol
Output Voltage Low
0.2
V
Vil
Input low Switching
Threshold
-
0.8
V
Vih
Input High Switching
Threshold
2.0
-
V
Table 6.7 USB I/O Pin (USBDP, USBDM) Characteristics
6.4 MTP Memory Reliability Characteristics
The internal 2048 Byte MTP memory has the following reliability characteristics:
Parameter
Value
Unit
Data Retention
10
Years
Write Cycle
2,000
Cycles
Read Cycle
Unlimited
Cycles
Table 6.8 MTP memory Characteristics
6.5 Internal Clock Characteristics
The internal Clock Oscillator has the following characteristics:
Parameter
Value
Unit
Minimum
Typical
Maximum
Frequency of Operation
(see Note 1)
11.98
12.00
12.02
MHz
Clock Period
83.19
83.33
83.47
ns
Duty Cycle
45
50
55
%
Table 6.9 Internal Clock Characteristics
Note 1: Equivalent to +/-1667ppm
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7 USB Power Configurations
The following sections illustrate possible USB power configurations for the FT201X. The illustrations have
omitted pin numbers for ease of understanding since the pins differ between the FT201XS and FT201XQ
package options.
All USB power configurations illustrated apply to both package options for the FT201X device. Please refer
to Section 11 for the package option pin-out and signal descriptions.
7.1 USB Bus Powered Configuration
FT201X
1
2
3
4
5
SHIELD
Ferrite
Bead
GND
GND
VCC
GND
VCC
3V3OUT
USBDM
USBDP
VCCIO
VCC
AGND
GND
RESET#
100nF
100nF
10nF
4.7uF+
27R
27R
GND
47pF 47pF
Figure 7.1 Bus Powered Configuration
Figure 7.1 Illustrates the FT201X in a typical USB bus powered design configuration. A USB bus powered
device gets its power from the USB bus. Basic rules for USB bus power devices are as follows –
i) On plug-in to USB, the device should draw no more current than 100mA.
ii) In USB Suspend mode the device should draw no more than 2.5mA.
iii) A bus powered high power USB device (one that draws more than 100mA) should use one of
the CBUS pins configured as PWREN# and use it to keep the current below 100mA on plug-in
and 2.5mA on USB suspend.
iv) A device that consumes more than 100mA cannot be plugged into a USB bus powered hub.
v) No device can draw more than 500mA from the USB bus.
The power descriptors in the internal MTP memory of the FT201X should be programmed to match the
current drawn by the device.
A ferrite bead is connected in series with the USB power supply to reduce EMI noise from the FT201X and
associated circuitry being radiated down the USB cable to the USB host. The value of the Ferrite Bead
depends on the total current drawn by the application. A suitable range of Ferrite Beads is available from
Laird Technologies (http://www.lairdtech.com), for example Laird Technologies Part # MI0805K601R-10.
Note: If using PWREN# (available using the CBUS) the pin should be pulled to VCCIO using a 10kΩ
resistor.
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FT201X USB I2C SLAVE IC Datasheet
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7.2 Self Powered Configuration
FT201X
1
2
3
4
5
SHIELD
GND
GND
VCC
GND
VCC
3V3OUT
USBDM
USBDP
VCCIO
VCC(3.3-5.25V)
AGND
GND
RESET#
100nF
100nF
100nF
4.7uF
+
GND
4k7
10k
27R
27R
47pF 47pF
GND
VBUS_SENSE
Figure 7.2 Self Powered Configuration
Figure 7.2 illustrates the FT201X in a typical USB self-powered configuration. A USB self-powered device
gets its power from its own power supply, VCC, and does not draw current from the USB bus. The basic
rules for USB self-powered devices are as follows –
i) A self-powered device should not force current down the USB bus when the USB host or hub
controller is powered down.
ii) A self-powered device can use as much current as it needs during normal operation and USB
suspend as it has its own power supply.
iii) A self-powered device can be used with any USB host, a bus powered USB hub or a self-
powered USB hub.
The power descriptor in the internal MTP memory of the FT201X should be programmed to a value of
zero (self-powered).
In order to comply with the first requirement above, the USB bus power (pin 1) is used to control the
VBUS_Sense pin of the FT201X device. When the USB host or hub is powered up an internal 1.5kΩ
resistor on USBDP is pulled up to +3.3V, thus identifying the device as a full speed device to the USB
host or hub. When the USB host or hub is powered off, VBUS_Sense pin will be low and the FT201X is
held in a suspend state. In this state the internal 1.5kΩ resistor is not pulled up to any power supply
(hub or host is powered down), so no current flows down USBDP via the 1.5kΩ pull-up resistor. Failure to
do this may cause some USB host or hub controllers to power up erratically.
Figure 7.2 illustrates a self-powered design which has a +3.3V to +5.25V supply.
Note:
1. When the FT201X is in reset, the interface I/O pins are tri-stated. Input pins have internal 75kΩ
pull-up resistors to VCCIO, so they will gently pull high unless driven by some external logic.
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FT201X USB I2C SLAVE IC Datasheet
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7.3 USB Bus Powered with Power Switching Configuration
FT201X
1
2
3
4
5
SHIELD
Ferrite
Bead
GND
GND
VCC
GND
VCC
3V3OUT
USBDM
USBDP
VCCIO
AGND
GND
RESET#
100nF
100nF
10nF
4.7uF+
CBUS3
PWREN#
100k
1k
Switched 5V Power to
External Logic
0.1uF0.1uF
P Channel Power
MOSFET
27R
27R
47pF
47pF
GND
Figure 7.3 Bus Powered with Power Switching Configuration
A requirement of USB bus powered applications, is when in USB suspend mode, the application draws a
total current of less than 2.5mA. This requirement includes external logic. Some external logic has the
ability to power itself down into a low current state by monitoring the PWREN# signal. For external logic
that cannot power itself down in this way, the FT201X provides a simple but effective method of turning
off power during the USB suspend mode.
Figure 7.3 shows an example of using a discrete P-Channel MOSFET to control the power to external
logic. A suitable device to do this is an International Rectifier (www.irf.com) IRLML6402, or equivalent. It
is recommended that a “soft start” circuit consisting of a 1kΩ series resistor and a 0.1μF capacitor is used
to limit the current surge when the MOSFET turns on. Without the soft start circuit it is possible that the
transient power surge, caused when the MOSFET switches on, will reset the FT201X or the USB host/hub
controller. The soft start circuit example shown in Figure 7.3 powers up with a slew rate of
approximaely12.5V/ms. Thus supply voltage to external logic transitions from GND to +5V in
approximately 400 microseconds.
As an alternative to the MOSFET, a dedicated power switch IC with inbuilt “soft-start” can be used. A
suitable power switch IC for such an application is the Micrel (www.micrel.com) MIC2025-2BM or
equivalent.
With power switching controlled designs the following should be noted:
i) The external logic to which the power is being switched should have its own reset circuitry to
automatically reset the logic when power is re-applied when moving out of suspend mode.
ii) Set the Pull-down on Suspend option in the internal FT201X MTP memory.
iii) One of the CBUS Pins should be configured as PWREN# in the internal FT201X MTP memory, and
used to switch the power supply to the external circuitry.
iv) For USB high-power bus powered applications (one that consumes greater than 100mA, and up
to 500mA of current from the USB bus), the power consumption of the application must be set in
the Max Power field in the internal FT201X MTP memory. A high-power bus powered application
uses the descriptor in the internal FT201X MTP memory to inform the system of its power
requirements.
v) PWREN# gets its VCC from VCCIO. For designs using 3V3 logic, ensure VCCIO is not powered
down using the external logic. In this case use the +3V3OUT.
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FT201X USB I2C SLAVE IC Datasheet
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8 Application Examples
The following sections illustrate possible applications of the FT201X. The illustrations have omitted pin
numbers for ease of understanding since the pins differ between the FT201XS and FT201XQ package
options.
8.1 USB to I2C Converter
FT201X
1
2
3
4
5
SHIELD
Ferrite
Bead
GND
GND
VCC
GND
VCC
3V3OUT
USBDM
USBDP
VCCIO
VCC
AGND
GND
RESET#
100nF
100nF
10nF
4.7uF+
SDA
SCL SCL
SDA I2C MASTER DEVICE
VCCIO
1k 1k
27R
27R
GND
47pF 47pF
Figure 8.1 Application Example showing USB to I2C Converter
An example of using the FT201X as an I2C peripheral is shown in Figure 8.1. The FT201X is the slave on
the I2C bus.
Therefore the clock supplied to the SCL pin must come from the I2C Master. The device will support
standard I2C data rates such as 100 kbit/s standard mode (SM), 400 kbit/s fast mode (FM), 1 Mbit/s Fast
mode plus (FM+), and 3.4 Mbit/s High Speed mode (HS).
The data line SDA is bi- directional.
The master is initially in master transmit mode by sending a start bit followed by the 7-bit address of the
slave it wishes to communicate with, which is finally followed by a single bit representing whether it
wishes to write(0) to or read(1) from the slave.
If the slave (FT201X) exists on the bus then it will respond with an ACK bit (active low for acknowledged)
for that address. The master then continues in either transmit or receive mode (according to the
read/write bit it sent), and the slave continues in its complementary mode (receive or transmit,
respectively).
The address and the data bytes are sent most significant bit first. The start bit is indicated by a high-to-
low transition of SDA with SCL high; the stop bit is indicated by a low-to-high transition of SDA with SCL
high.
If the master wishes to write to the slave then it repeatedly sends a byte with the slave sending an ACK
bit. (In this situation, the master is in master transmit mode and the slave is in slave receive mode.)
If the master wishes to read from the slave then it repeatedly receives a byte from the slave, the master
sending an ACK bit after every byte but the last one. (In this situation, the master is in master receive
mode and the slave is in slave transmit mode.)
The master then ends transmission with a stop bit, or it may send another START bit if it wishes to retain
control of the bus for another transfer (a "combined message").
I²C defines three basic types of message, each of which begins with a START and ends with a STOP:
Copyright © Future Technology Devices International Limited 26
FT201X USB I2C SLAVE IC Datasheet
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Single message where a master writes data to a slave;
Single message where a master reads data from a slave;
Combined messages, where a master issues at least two reads and/or writes to one or more
slaves
In a combined message, each read or write begins with a START and the slave address. After the first
START, these are also called repeated START bits; repeated START bits are not preceded by STOP bits,
which is how slaves know the next transfer is part of the same message.
The I2C address of the FT201X is stored in the device internal MTP memory.
Please refer to the I2C specification for more information on the protocol.
8.2 USB Battery Charging Detection
A recent addition to the USB specification (http://www.usb.org/developers/) is to allow for additional
charging profiles to be used for charging batteries in portable devices. These charging profiles do not
enumerate the USB port of the peripheral. The FT201X device will detect that a USB compliant dedicated
charging port (DCP) is connected. Once detected while in suspend mode a battery charge detection signal
is provided to allow external logic to switch to charging mode as opposed to operation mode.
To use the FT201X with battery charging detection the CBUS pins must be reprogrammed to allow for the
BCD Charger output to switch the external charger circuitry on. The CBUS pins are configured in the
internal MTP memory with the free utility FT_PROG. If the charging circuitry requires an active low signal
to enable it, the CBUS pin can be programmed to BCD Charger# as an alternative.
When connected to a USB compliant dedicated charging port (DCP, as opposed to a standard USB host)
the device USB signals will be shorted together and the device suspended. The BCD charger signal will
bring the LTC4053 out of suspend and allow battery charging to start. The charge current in the example
below is 1A as defined by the resistance on the PROG pin.
X-Chip Pin Function
EEPROM Setting
CBUS0 BCD Battery Options
Battery Charger Enable
Force Power Enable
De-acticate Sleep
X
GND
GND
0.1uF 0.1uF
GND
GND
600R/2A
10nF
VBUS 3V3OUT
0.1uF
0R
GNDSLD GND
27R
27R
VBUS 1
D- 2
D+ 3
GND 5
ID 4
CN USB
VCC
2
FAULT
3
TIMER
4
GND
5NTC 6
PROG 7
SHDN 8
BAT 9
ACPR 10
CHRG
1
GND 11
LTC4053EDD
GND
3V3OUT 3V3OUT
4.7uF
0.1uF
GND
VBUSVBUS
GND
VBATT
GND
GND
1K5
GND
1
TB3.5mm
VBUS VBUS
NTC
0.1uF
GND
VBUS
1uF
1R
GND
VBUS
BCD
2K2
GND
JP1
1-2
2-3 NCT Enabled
NCT Available
JP1
SIP-3
NTC
GND
NCT Disabled (Default)
JUMPER-2mm
4K32 1%
GND
DP
DM
3V3OUT
RESET#
VCC
GND
CBUS0
VCCIO
FT201X
BCD
1A when connected to a dedicated charger port
0A when enumerated
0A when in sleep
0A when not enumerated and not in sleep
+
-
NCT
N.F.
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FT201X USB I2C SLAVE IC Datasheet
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Figure 8.2 USB Battery Charging Detection (1- pin)
Alternatively the PWREN# And SLEEP pins may be used to control the LTC4053 such that a battery may
be charged from a standard host (low current) or from a dedicated charging port (high current). In such
a design as shown below the charge current would need to be limited to 0.4A to ensure that the USB host
power limit is not exceeded.
X-Chip Pin Function
EEPROM Setting
CBUS5
CBUS6 SLEEP#
PWREN#
Battery Options
Battery Charger Enable
Force Power Enable
De-acticate Sleep X
X
X
SLEEP#
PWREN#
DP
DM
3V3OUT
VCORE
RESET#
VCC
CBUS6
CBUS5
VCCIO
U1
FT201X
0.4A when connected to a dedicated charger port
GND
GND
0.1uF 0.1uF
GND
GND
600R/2A
10nF
VBUS 3V3OUT
0.1uF
0R
GNDSLD GND
27R
27R
VBUS 1
D- 2
D+ 3
GND 5
ID 4
CN USB
3V3OUT 3V3OUTVBUS VBUS
N.F.
16K5 1%
GND
4K32 1%
PWREN#
0.4A when enumerated
0A when in sleep mode
0.1A when not enumerated and not in sleep mode
VCC
2
FAULT
3
TIMER
4
GND
5NTC 6
PROG 7
SHDN 8
BAT 9
ACPR 10
CHRG
1
GND 11
LTC4053EDD
GND
4.7uF
0.1uF
GND
VBUSVBUS
GND
VBATT
GND
GND 1
TB3.5mm
NTC
0.1uF
GND
VBUS
1uF
1R
GND
VBUS
2K2
GND
JP1
1-2
2-3 NCT Enabled
NCT Available
JP1
SIP-3
NTC
GND
NCT Disabled (Default)
JUMPER-2mm
4K32 1%
+
-
NCT
SLEEP#
Figure 8.3 USB Battery Charging Detection (2- pin)
In the example above the FT201X SLEEP pin is used to enable/disable the LTC4053, while the PWREN#
signal alters the charging current by altering the resistance on the LTC4053 PROG pin.
A third option shown in the example below uses the SLEEP signal from the FT201X to enable / disable the
battery charger. The BCD# and PWREN# signals are then used to alter the resistance on the PROG pin of
the LTC4053 which controls the charge current drawn from the USB connector.
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X-Chip Pin Function
EEPROM Setting
CBUS0
CBUS1
CBUS2
BCD#
PWREN#
SLEEP#
Battery Options
Battery Charger Enable
Force Power Enable
De-acticate Sleep X
X
PWREN#
GND
CBUS2 10
DP
DM
3V3OUT
RESET#
VCC
GND
CBUS1 17
CBUS0 18
VCCIO
FT201X
BCD#
SLEEP#
GND
GND
0.1uF 0.1uF
GND
GND
600R/2A
10nF
VBUS 3V3OUT
0.1uF
0R
GNDSLD GND
27R
27R
VBUS 1
D- 2
D+ 3
GND 5
ID 4
CN USB
3V3OUT 3V3OUTVBUS VBUS
N.F.
1K5 - 1%16K5 1%
GND
BCD#
4K32 1%
PWREN#
1A when connected to a dedicated charger port
0.4A when enumerated
0A when in sleep
0.1A when not enumerated and not in sleep
VCC
2
FAULT
3
TIMER
4
GND
5NTC 6
PROG 7
SHDN 8
BAT 9
ACPR 10
CHRG
1
GND 11
LTC4053EDD
GND
4.7uF
0.1uF
GND
VBUSVBUS
GND
VBATT
GND
GND 1
TB3.5mm
NTC
0.1uF
GND
VBUS
1uF
1R
GND
VBUS
2K2
GND
JP1
1-2
2-3 NCT Enabled
NCT Available
JP1
SIP-3
NTC
GND
NCT Disabled (Default)
JUMPER-2mm
4K32 1%
+
-
NCT
SLEEP#
Figure 8.4 USB Battery Charging Detection (3 - pin)
To calculate the equivalent resistance on the LTC4053 PROG pin select a charge current, then Res =
1500V/Ichg
For more configuration options of the LTC4053 refer to:
AN_175_Battery Charging Over USB
Note: If the FT201X is connected to a standard host port such that the device is enumerated the battery
charge detection signal is inactive as the device will not be in suspend.
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9 USB and I2C Interfacing
This section covers the transfer of data from USB to I2C and vice versa.
Please note that the FT200XD and FT201X are I2C slave devices only and should be interfaced to an I2C
host (often in a microcontroller or FPGA). If an I2C master is required, please see the FT232H, FT2232H,
FT4232H and FT2232D devices.
This section covers transfer of data only. The USB and I2C interfaces on the FT200XD and FT201X can
also be used for programming of the MTP memory, which is covered in a separate section.
Throughout this section, the reference FT-X applies to the FT200XD and FT201X devices, as the other
members of the FT-X family do not have I2C interfaces.
9.1 Host Interface (USB)
From the host computer’s point of view, the I2C data can be sent and received in the same way as when
interfacing to one of the standard UART devices such as the FT232R. The FT-X handles the entire I2C
protocol inside the chip and so reading and writing data does not require any special programming from
the PC side. It can be treated as a simple data bridge.
9.1.1 VCP and D2xx Interfaces
Like the other FTDI devices, the host can use D2xx commands or can use a Virtual COM Port (VCP) to
communicate with the device.
D2xx Interface
The D2xx method allows the application software to use the functions in the FTDI D2xx library to
communicate directly with the device. This is a library provided free-of-charge by FTDI and is available
within the driver download files at the link below.
http://www.ftdichip.com/Drivers/D2XX.htm
It includes functions to find the FTDI devices on the system, open a particular device, send data to the
device and read data from the device. Any data written using FT_Write, for example, will be sent to the
FT-X chip and will be available for the external I2C Master to read. As mentioned above, only the data
itself needs to be sent as the FT-X handles all of the I2C specific protocol.
There are many other functions available, and full details can be found in the D2xx Programmers Guide.
Virtual COM Port Interface
If using the Virtual Com Port (VCP), the device will appear as if it were a real COM port on the computer.
This is useful where an application has already been written to use an RS232 port on the computer as it
allows that application to treat the FT-X as if it were a real COM port. This port can be opened in a
terminal program or a custom application in the same way as a serial port would be opened. Data can
then be sent or received using standard serial / COM port functions.
No I2C decoding is required as the chip itself handles the I2C protocol. Because of this, even I2C versions
of the FT-X family can be used with the VCP interface. Any data which the host PC sends to the Virtual
COM Port (for example, typed into the terminal window in HyperTerminal) will be sent over USB to the
FT-X and can then be read by the external I2C Master. Likewise, any data written to the FT-X over I2C will
be sent to the PC where the terminal program will display it.
Since the FT-X is the I2C slave and does not generate a clock signal, the settings such as baud rate and
handshaking do not have any effect.
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D2xx and VCP Interface under Windows
In Windows systems, the VCP driver is actually an additional layer on top of the D2xx driver. The D2xx
driver is always loaded and the VCP later may or may not be loaded on top of it, depending on the
requirements of the application.
When VCP is disabled, the device will appear only under Universal Serial Bus Controllers in the Device
Manager and no COM port is exposed. When the VCP is enabled, the device will appear under both the
Universal Serial Bus Controllers and the Ports (COM & LPT) sections in Device Manager.
The VCP interface will be disabled by default in the FT200XD and FT201X but can be enabled in one of
the following ways:
- An option bit in the MTP memory on the chip is checked each time that the device is enumerated,
and can cause the host computer to load the VCP layer. This allows each individual hardware unit
to enable or disable VCP as per its requirements. The MTP information in section 10 has further
details. FT_Prog can also be used to modify the MTP settings.
- The user may open the Properties for the device under Universal Serial Bus Controllers in Device
Manager in Windows and tick a box to load the VCP. Re-enumeration of the FT-X is necessary to
enable the new setting.
- By editing the driver FtdiBus.inf file (please refer to AN_107). Note that the FT_INF utility
available from the FTDI website can be used to help create the modified inf files.
In other Operating systems (e.g. Linux, Mac and Windows CE), there are separate drivers for D2xx and
VCP, and only one of these drivers may be installed at any time. Therefore, the mode is selected by
installing the associated driver instead and the selection defined in the bullet points above has no effect.
9.1.2 Reading and Writing Data
Data from FT-X to the Host
When data is to be sent from the host computer to the external I2C master, the software application
writes this data to the FTDI driver using VCP or D2xx and this data is sent by the driver over USB to the
buffer in the device.
The external I2C master device may then perform an I2C read (Master receiver, Slave transmitter)
operation to retrieve the data.
The external I2C master should check if data is available to ensure that the data which has been read is
valid. The methods for this are described in section 9.2.2 below.
Data from Host to the FT-X
When data is to be sent from the external I2C master to the host computer, the external master performs
an I2C write (Master transmitter, Slave receiver) operation to the FT-X.
The FT-X stores this in its buffer and the data is sent back to the driver on the host computer over USB.
As with other FTDI devices, this happens when either the buffer in the device fills or when the latency
timer rolls over (so that partially filled buffers do not wait indefinitely), whichever happens first.
Note that when writing data to the FT-X over I2C, the external master should check whether there is
space available in the buffer inside the FT-X. It can do this using the methods shown in section 9.2.2
below.
The host computer application can then read the data from the driver buffer using the VCP interface or
the D2xx commands. In the case of D2xx, the number of bytes available may be determined using the
FT_GetQueueStatus command before doing the FT_Read.
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9.2 I2C Interface
From an I2C point of view, the FT-X behaves as a standard I2C slave. Data transfers take the same form
as a standard I2C communication. In addition to reading and writing, there are some other commands
which can be used to determine the status of the device and these are covered in this section and in
further detail in section 9.3.
Note: This section uses 7-bit addressing in the examples. It uses eight characters to describe the seven
address bits and the single read/write bit. For example, 1110 011 1 means address 0x73 with the
Read/Write bit set to 1, and therefore corresponds to a read of address 0x73. Data values are
represented in bytes, for example, 1010 0101 for data value 0xA5.
9.2.1 Addressing
The FT-X can be given a custom slave address on the I2C bus. This is stored in MTP memory and can be
re-programmed over USB or I2C. Please see the separate MTP Programming information in section 10.
The slave address is used when reading and writing to the device. The FT-X supports both 7-bit and 10-
bit addressing.
The general call address (0000 000 0) is for addressing every device on the bus. Some slaves do not
support the General Call Address though the FT-X devices do support it. They will acknowledge this
address, receive the second byte and interpret it. There are several commands available for this second
byte. The FT-X will support the Software Reset command which is part of the I2C specification as well as
other custom FTDI commands. These are covered in more detail later in the Other I2C Commands
section.
9.2.2 Data Transfers
Reading and Writing
For all I2C data transfers to and from the FT-X, the slave address of the FT-X is used. The figure below
shows a typical 7-bit address transfer for each direction.
Figure 9.1: Data transfers using 7-bit addressing
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The figure below summarises all of the transfers available (7-bit and 10-bit addressing).
Figure 9.2: Data transfers with 7-bit and 10-bit addressing modes
Flow Control when Reading
When reading data, it is important to know if there is data available to read over I2C and if the data read
is valid. There are three methods by which to check whether the data being read is valid.
- Checking the I2C_TXE# line, which indicates whether the transmit buffer is empty. This signal
can be mapped to the CBUS pins. This line does not indicate the number of bytes available. If the
line is asserted, there are one or more bytes in the transmit buffer. Note that the Transmit buffer
is the buffer which holds data which has come from the host computer and is going to be read by
the external I2C master.
- Do a read over I2C (Master receiver, Slave transmitter) and check whether the FT-X
acknowledges the address phase. The FT-X will NAK the address phase if there is no data to read.
- If bursting data, then there is not an address phase for each byte. In this case, it is not possible
to tell when the buffer has emptied and therefore when you are no longer reading valid bytes. In
this case, a Data Available check can be carried out first. If the byte after the general call address
is 0x0C (0000 1100), the FT-X returns the Data Available Count to indicate the number of bytes
available for burst read. Please also refer to section 9.3. Note that because this returns a single
byte, the maximum value is 0xFF, and so a value of 0xFF indicates that there are 255 or more
bytes available.
Figure 9.3: Checking the Data Available Count
Flow Control when Writing
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When writing data (data going from I2C toward the host computer), it is important to check if there is
space available and if the FT-X accepted the byte written. There are two methods by which to check
whether space is available.
- Check the I2C_RXF# line, which indicates whether the Receive buffer is full. This line indicates
that there is at least one empty byte available in the buffer. However, there is no indication of
how many bytes are available. This signal can be mapped to the CBUS pins. Note that the
Receive buffer is the buffer which holds data which has come from the external I2C master and is
going to the host computer over USB.
- Do a write over I2C (Master transmitter, Slave receiver) and check if the FT-X ACKs. The FT-X will
NAK if there is no space in the buffer for the data to be written into. The FT-X will NACK in the
address phase if this is the first byte being written and there is no space available. If the buffer
becomes full during a burst write, the FT-X will NACK any bytes during the data phase which
cannot be accommodated in the buffer.
Note that because the acknowledgement can be checked for each byte written (since the FT-X slave is
generating the acknowledge when writing to it), there is no command to ask the FT-X how much buffer
space is available.
9.3 Other I2C Commands
Soft reset
This uses the General Call Address. If the second byte is 0x06 (0000 0110) it will be interpreted by the
FT-X as the Soft Reset command, which clears all buffers.
Flush command
This uses the General Call Address. If the second byte is 0x0E (0000 1110) it will be interpreted by the
FT-X as the Flush command and the Transmit and Receive buffers will be flushed of all data.
Figure 9.4: Flush data command
Read Data Available command
This uses the General Call Address. If the second byte is 0x0C (0000 1100) it will be interpreted by the
block as the Read Data Available command and on the next I2C read cycle following this command, the
data will hold the number of bytes available for burst read.
Figure 9.5: Reading the amount of data available
USB State command
This uses the General Call Address. If the second byte is 0x16 (0001 0110) it will be interpreted by the
block as the USB State command and on the next read cycle following this command, the data will hold
the coded USB State value. The USB state allows you to check the current USB enumeration state:
0x00 = Suspended.
0x01 = Default.
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0x02 = Addressed.
0x03 = Configured.
Note: The Configured state is the normal operating state.
Further details of these states can be found in Chapter 9 of the USB 2.0 Specification from the USB
Implementers Forum website (http://www.usb.org).
Figure 9.6: Checking the USB State
Device ID command
This command uses the Slave address of the FT-X. The master issues the 1111 100 0 command (0x7c
write) followed by the slave address with the direction bit as either 0 or 1 (don’t care). The master then
sends a repeated start followed by the 1111 100 1 command (0x7c read). The FT-X responds with 3
bytes containing the manufacturer ID (12 bits), part ID (9 bits) and revision (3 bits). The master ends
reading with a NACK.
Note: In the case where the master keeps ACKing the data, it has to wrap around and the slave (the FT-
X) will keep sending the 3 bytes of its ID.
Figure 9.7: Reading the Device ID
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10 Internal MTP Memory Configuration
The FT201X includes an internal MTP memory which holds the USB configuration descriptors, other
configuration data for the chip and also user data areas. Following a power-on reset or a USB reset the
FT201X will scan its internal MTP memory and read the USB configuration descriptors stored there
In many cases, the default values programmed into the MTP memory will be suitable and no re-
programming will be necessary. The defaults can be found in Section 10.1.
The MTP memory in the FT201X can be programmed over USB or over the I2C bus if the values need to
be changed for a particular application. Further details of this are provided from section 10.2 onwards.
Users who do not have their own USB Vendor ID but who would like to use a unique Product ID in their
design can apply to FTDI for a free block of unique PIDs. See TN_100 – USB Vendor ID/Product ID
Guidelines for more details.
10.1 Default Values
The default factory programmed values of the internal MTP memory are shown in the following table:
Parameter
Value
Notes
USB Vendor ID (VID)
0403h
FTDI default VID (hex)
USB Product UD (PID)
6015h
FTDI default PID (hex)
Serial Number Enabled?
Yes
Serial Number
See Note
A unique serial number is generated and
programmed into the MTP memory during device
final test.
Pull down I/O Pins in USB
Suspend
Disabled
Enabling this option will make the device pull down
on the UART interface lines when in USB suspend
mode (PWREN# is high).
Manufacturer Name
FTDI
Product Description
FT201X USB I2C
Max Bus Power Current
90mA
Power Source
Bus Powered
Device Type
FT201X
USB Version
0200
Returns USB 2.0 device description to the host.
Note: The device is a USB 2.0 Full Speed device
(12Mb/s) as opposed to a USB 2.0 High Speed
device (480Mb/s).
Remote Wake Up
Disabled
DBUS Drive Current
Strength
4mA
Options are 4mA, 8mA, 12mA, 16mA
DBUS slew rate
Slow
Options are slow or fast
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Parameter
Value
Notes
DBUS Schmitt Trigger
Enable
Normal
Options are normal or Schmitt
CBUS Drive Current
Strength
4mA
Options are 4mA, 8mA, 12mA, 16mA
CBUS slew rate
Slow
Options are slow or fast
CBUS Schmitt Trigger
Enable
Normal
Options are normal or Schmitt
Load VCP Driver
Disabled
Enabling this will load the VCP driver interface for
the device.
I2C Address
22h
The I2C device address
CBUS0
SLEEP#
Default configuration of CBUS0 – USB suspend mode.
CBUS1
TRI-STATE
Default configuration of CBUS1 – TRI-STATE.
CBUS2
TRI-STATE
Default configuration of CBUS2 – TRI-STATE
CBUS3
PWREN#
Default configuration of CBUS3 – Power enable. Low
after USB enumeration, high during USB suspend
mode.
CBUS4
VBUS_Sense
Default configuration of CBUS4– Power enable. Low
after USB enumeration, high during USB suspend
mode.
CBUS5
Keep_Awake#
Prevents the device from entering suspend state
when unplugged. May be used if programming the
MTP memory over I2C.
Table 10.1 Default Internal MTP Memory Configuration
Note: These values apply to Revision D and later. The previous revisions had different CBUS defaults.
10.2 Methods of Programming the MTP Memory
10.2.1 Programming the MTP memory over USB
The MTP memory on all FT-X devices can be programmed over USB. This method is the same as for the
EEPROM on other FTDI devices such as the FT232R. No additional hardware, connections or programming
voltages are required. The device is simply connected to the host computer in the same way that it would
be for normal applications, and the FT_Prog utility is used to set the required options and program the
device.
The FT_Prog utility is provided free-of-charge from the FTDI website, and can be found at the link below.
The user guide is also available at this link.
http://www.ftdichip.com/Support/Utilities.htm#FT_Prog
Additionally, D2XX commands can be used to program the MTP memory from within user applications.
For more information on the commands available, please refer to D2XX Programmers Guide.
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10.2.2 Programming the MTP memory over I2C
In the FT201X device, it is possible to program the MTP memory over its I2C interface. This is the same
interface which is used in the normal application of the FT201X and would normally be connected to the
I2C master implemented in a microcontroller (MCU) or FPGA. However, special commands can also be
used to access the MTP memory in the FT201X over the same I2C connection, allowing the MCU/FPGA to
read and write locations in the MTP memory. No additional hardware, connections or programming
voltages are required.
Warning: When programming locations in the MTP which are covered by the checksum, the checksum
value must always be programmed to the correct value before any device reset takes place. If the device
starts up or resets with an incorrect checksum, I2C communication will not be possible. Recovery is only
possible by re-programming the checksum to the correct value over USB.
Two examples where it may be desired to use the I2C interface to write and read the MTP Memory are
given below. In some cases, the application may use both of these possibilities.
1. To store and retrieve application specific data such as calibration constants in the user area (e.g.
if the overall application was an analog measurement system). This can avoid the need for an
extra EEPROM chip on the application board.
2. To read and write the configuration data (e.g. custom VID, PID, description strings or CBUS
signal selection to enable signals for battery charging etc.) without a USB host. This could allow
an MCU/FPGA to configure the FT201X during production testing of the finished device or even
when in use in the field.
The information in the rest of this chapter can be used to implement the storing and reading of
application data in the user area as in example 1 above. Example 2 requires details of the configuration
data stored in the MTP memory. Further details can be found in AN_201.
10.3 Memory Map
The FT-X family MTP memory has various areas which come under three main categories:
User Memory Area
Configuration Memory Area (writable)
Configuration Memory Area (non-writable)
Memory Area Description
Word Address
User Memory Area 2
Accessible via USB, I2C and FT1248
0x3FF - 0x80
Configuration Memory Area
Accessible via USB, I2C and FT1248
0x7E - 0x50
Configuration Memory Area
Cannot be written
0x4E - 0x40
User Memory Area 1
Accessible via USB, I2C and FT1248
0x3E - 0x12
Configuration Memory Area
0x10 - 0x00
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Accessible via USB, I2C and FT1248
Figure 10.1: Simplified memory map for the FT201X
User Memory Area
The User Memory Areas are highlighted in Green on the memory map. They can be read and written via
both USB and I2C. All locations within this range are freely programmable; no areas have special
functions and there is no checksum for the user area.
Note that the application should take into account the specification for the number of write cycles in
Section 6.4 if it will be writing to the MTP memory multiple times.
Configuration Memory Area (writable)
This area stores the configuration data for the device, including the data which is returned to the host in
the configuration descriptors (e.g. the VID, PID and string descriptions) and also values which set the
hardware configuration (the signal assigned to each CBUS pin for example).
These values can have a significant effect on the behaviour of the device. Steps must be taken to ensure
that these locations are not written to un-intentionally by an application which is intended to access only
the user area.
This area is included in a checksum which covers configuration areas of the memory, and so changing
any value can also cause this checksum to fail. When changing any locations covered by the checksum,
the checksum value must always be updated before a device reset or power cycle takes place (i.e. before
the device uses the new MTP settings). Devices with incorrect checksum will require programming over
USB to recover and correct the checksum.
Configuration Memory Area (non-writable)
This is a reserved area and the application should not write to this area of memory. Any attempt to write
these locations will fail.
10.4 Hardware Requirements
The hardware is the same as for a typical USB-I2C application and no additional hardware or
programming voltages are required. The I2C connections are the same as shown in Section 8.1. For the
USB connections, either a bus-powered configuration (see Section 7.1 and 7.3) or a self-powered
configuration (see Section 7.2) could be used.
Warning: When programming locations in the MTP which are covered by the checksum, the checksum
value must always be programmed to the correct value before any device reset takes place. If the device
starts up or resets with an incorrect checksum, I2C communication will not be possible. Recovery is only
possible by re-programming the checksum to the correct value over USB.
10.5 Protocol
The I2C MTP memory protocol consists of 3 commands:
Address MTP memory (0x10)
Write MTP memory (0x12)
Read MTP memory (0x14)
For further details on the I2C protocol, refer to section 5.
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10.5.1 Address MTP memory (0x10)
This consists of a general call with a command phase followed by 2 data bytes which represent the MTP
memory address allowing users to address, potentially, up to 64K byte addresses.
10.5.2 Write MTP memory (0x12)
This consists of a general call with a command phase followed by 1 data byte which shall be programmed
into the MTP memory at the address location set by the MTP memory address command.
10.5.3 Read MTP memory (0x14)
This consists of a general call with a command phase followed by 1 data byte which is the data read from
the MTP memory at the address location set by the MTP memory address command.
10.5.4 Examples of Writing and Reading
When performing MTP memory write and read requests via the I2C protocol, users must first issue the
MTP address command along with 2 bytes representing the MTP memory address. The acknowledge
phase of this command represents the current status of the MTP memory (whether it is busy or not). If
the MTP memory is being accessed during an I2C access then the respective command and data phases
will NAK the master. The address will only be updated when the MTP memory is inactive.
Writing
The first part of the communication sets the address, and this is followed by the write command along
with the data to be written. The MTP memory write itself will be initiated when the FT201X receives an
MTP memory write command followed by a single data byte. The ACK phase represents the current
activity of the MTP memory (whether it is busy or not busy). A successful write will only occur when both
status phases acknowledge the master indicating that the MTP memory can start the write. Users wishing
to determine if the MTP memory write was successful should immediately try an MTP memory read to
verify the new contents.
This process of writing to the MTP memory is shown below:
Figure 10.2: Write EEPROM command sequence
Reading
In a similar way, the read is carried out as shown below.The first part of the communication sets the
address, and this is followed by the read command and a read cycle used to retrieve the data read back
from that address.
An MTP memory read will be initiated when the I2C slave receives an MTP read command. The
acknowledge during the command phase indicates whether or not the MTP memory will be able to service
the read request. If it is possible to carry out the read, the I2C moves into the data phase where it can
either continue with the read transaction until the slave successful returns an ACK along with the data or
if it receives NAK during the data phase it can abort the read transfer and try again.
0000000 0 0001_0000 0
S/Sr General call addr R/!W A MTP ADDR cmd A/!A Sr Slave addr R/!W A MTP ADR MSB A A
0000000 0 0001_0010 0
S/Sr General call addr R/!W A MTP WR cmd A/!A Sr Slave addr R/!W A MTP WR DATA A P/Sr
MTP Memory Address Phase
MTP memory Write Phase
MTP ADR LSB
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FT201X USB I2C SLAVE IC Datasheet
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Figure 10.3: Read EEPROM command sequence
0000000 0 0001_0000 0
S/Sr General call addr R/!W A MTP ADDR cmd A/!A Sr Slave addr R/!W A MTP ADR MSB A A
0000000 0 0001_0100 1
S/Sr General call addr R/!W A MTP WR cmd A/!A Sr Slave addr R/!W A MTP WR DATA A P/Sr
MTP ADR LSB
MTP Memory Address Phase
MTP memory Read Phase
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11 Package Parameters
The FT201X is available in two different packages. The FT201XS is the SSOP-16 option and the FT201XQ
is the QFN-16 package option. The solder reflow profile for both packages is described in Section 11.5.
11.1 SSOP-16 Package Mechanical Dimensions
Figure 11.1 SSOP-16 Package Dimensions
The FT201XS is supplied in a RoHS compliant 16 pin SSOP package. The package is lead (Pb) free and
uses a ‘green’ compound. The package is fully compliant with European Union directive 2002/95/EC.
This package is nominally 4.90mm x 3.91mm body (4.90mm x 5.99mm including pins). The pins are on a
0.635 mm pitch. The above mechanical drawing shows the SSOP-16 package.
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11.2 SSOP-16 Package Markings
Figure 11.2 SSOP-16 Package Markings
The date code format is YYXX where XX = 2 digit week number, YY = 2 digit year number. This is
followed by the revision number.
The code XXXXXXXXXXXX is the manufacturing LOT code
FT201XS
-B
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11.3 QFN-16 Package Mechanical Dimensions
Figure 11.3 QFN-16 Package Dimensions
The FT201XQ is supplied in a RoHS compliant leadless QFN-16 package. The package is lead (Pb) free,
and uses a ‘green’ compound. The package is fully compliant with European Union directive 2002/95/EC.
This package is nominally 4.00mm x 4.00mm. The solder pads are on a 0.65mm pitch. The above
mechanical drawing shows the QFN-16 package. All dimensions in table are in millimetres.
The centre pad on the base of the FT201XQ is internally connected to GND. Do not place signal tracks on
the PCB top layer under this area. Connect to GND.
Copyright © Future Technology Devices International Limited 44
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11.4 QFN-16 Package Markings
Figure 11.4 QFN-16 Package Markings
The date code format is YYXX where XX = 2 digit week number, YY = 2 digit year number. This is
followed by the revision number.
The code XXXXXXX is the manufacturing LOT code.
FTDI
I
XXXXXXXXXX
FT201XQ
5
1
YYWW-B
8
12
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11.5 Solder Reflow Profile
The FT201X is supplied in Pb free 16 LD SSOP and QFN-16 packages. The recommended solder reflow
profile for both package options is shown in Figure 11.5.
Figure 11.5 FT201X Solder Reflow Profile
The recommended values for the solder reflow profile are detailed in Table 11.1. Values are shown for
both a completely Pb free solder process (i.e. the FT201X is used with Pb free solder), and for a non-Pb
free solder process (i.e. the FT201X is used with non-Pb free solder).
Profile Feature
Pb Free Solder Process
Non-Pb Free Solder Process
Average Ramp Up Rate (Ts to Tp)
3°C / second Max.
3°C / Second Max.
Preheat
- Temperature Min (Ts Min.)
- Temperature Max (Ts Max.)
- Time (ts Min to ts Max)
150°C
200°C
60 to 120 seconds
100°C
150°C
60 to 120 seconds
Time Maintained Above Critical Temperature
TL:
- Temperature (TL)
- Time (tL)
217°C
60 to 150 seconds
183°C
60 to 150 seconds
Peak Temperature (Tp)
260°C
240°C
Time within 5°C of actual Peak Temperature
(tp)
20 to 40 seconds
20 to 40 seconds
Ramp Down Rate
6°C / second Max.
6°C / second Max.
Time for T= 25°C to Peak Temperature, Tp
8 minutes Max.
6 minutes Max.
Table 11.1 Reflow Profile Parameter Values
Critical Zone: when
T is in the range
T to T
Temperature, T (Degrees C)
Time, t (seconds)
25 P
T = 25º C to T
tp
Tp
TL
t
Preheat
S
tL
Ramp Up Lp
Ramp
Down
T Max
S
T Min
S
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12 Contact Information
Head Office – Glasgow, UK
Branch Office – Tigard, Oregon, USA
Future Technology Devices International Limited
Unit 1, 2 Seaward Place, Centurion Business Park
Glasgow G41 1HH
United Kingdom
Tel: +44 (0) 141 429 2777
Fax: +44 (0) 141 429 2758
Future Technology Devices International Limited (USA)
7130 SW Fir Loop
Tigard, OR 97223-8160
USA
Tel: +1 (503) 547 0988
Fax: +1 (503) 547 0987
E-mail (Sales)
sales1@ftdichip.com
E-mail (Sales)
us.sales@ftdichip.com
E-mail (Support)
support1@ftdichip.com
E-mail (Support)
us.support@ftdichip.com
E-mail (General Enquiries)
admin1@ftdichip.com
E-mail (General Enquiries)
us.admin@ftdichip.com
Branch Office – Taipei, Taiwan
Branch Office – Shanghai, China
Future Technology Devices International Limited (Taiwan)
2F, No. 516, Sec. 1, NeiHu Road
Taipei 114
Taiwan , R.O.C.
Tel: +886 (0) 2 8797 1330
Fax: +886 (0) 2 8791 3576
Future Technology Devices International Limited (China)
Room 1103, No. 666 West Huaihai Road,
Shanghai, 200052
China
Tel: +86 21 62351596
Fax: +86 21 62351595
E-mail (Sales)
tw.sales1@ftdichip.com
E-mail (Sales)
cn.sales@ftdichip.com
E-mail (Support)
tw.support1@ftdichip.com
E-mail (Support)
cn.support@ftdichip.com
E-mail (General Enquiries)
tw.admin1@ftdichip.com
E-mail (General Enquiries)
cn.admin@ftdichip.com
Web Site
http://ftdichip.com
Distributor and Sales Representatives
Please visit the Sales Network page of the FTDI Web site for the contact details of our distributor(s) and sales
representative(s) in your country.
System and equipment manufacturers and designers are responsible to ensure that their systems, and any Future Technology Devices
International Ltd (FTDI) devices incorporated in their systems, meet all applicable safety, regulatory and system-level performance
requirements. All application-related information in this document (including application descriptions, suggested FTDI devices and other
materials) is provided for reference only. While FTDI has taken care to assure it is accurate, this information is subject to customer
confirmation, and FTDI disclaims all liability for system designs and for any applications assistance provided by FTDI. Use of FTDI
devices in life support and/or safety applications is entirely at the user’s risk, and the user agrees to defend, indemnify and hold
harmless FTDI from any and all damages, claims, suits or expense resulting from such use. This document is subject to change without
notice. No freedom to use patents or other intellectual property rights is implied by the publication of this document. Neither the whole
nor any part of the information contained in, or the product described in this document, may be adapted or reproduced in any material
or electronic form without the prior written consent of the copyright holder. Future Technology Devices International Ltd, Unit 1, 2
Seaward Place, Centurion Business Park,
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Appendix A – References
Document References
Useful Application Notes
AN232R-01 FT232R BitBangModes
AN_107 Advanced Driver Options
AN_121 Accessing the EEPROM User Area of FTDI Devices
AN_175 Battery Charger Detection over USB with FT-X Devices
TN_100 USB Vendor ID/ Product ID Guidelines
http://i2c2p.twibright.com/spec/i2c.pdf
http://www.usb.org/developers/
Acronyms and Abbreviations
Terms
Description
EHCI
Enhanced Host Controller Interface
FPGA
Field Programmable Gate Array
I2C
Inter-Integrated Circuit
LDO
Low Drop Out
LED
Light Emitting Diode
MCU
Micro Controller Unit
MTP
Multi-time Programmable
OHCI
Open Host Controller Interface
PLD
Programmable Logic Device
QFN
Quad Flat No-Lead
RoHS
Restriction of Hazardous Substances Directive
USB
Universal Serial Bus
UHCI
Universal Host Controller Interface
VCP
Virtual COM Port
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Appendix B - List of Figures and Tables
List of Figures
Figure 2.1 FT201X Block Diagram ................................................................................................... 4
Figure 3.1 QFN Schematic Symbol .................................................................................................. 7
Figure 3.2 SSOP Schematic Symbol ................................................................................................ 9
Figure 7.1 Bus Powered Configuration ........................................................................................... 22
Figure 7.2 Self Powered Configuration ........................................................................................... 23
Figure 7.3 Bus Powered with Power Switching Configuration ............................................................ 24
Figure 8.1 Application Example showing USB to I2C Converter .......................................................... 25
Figure 8.2 USB Battery Charging Detection (1- pin) ........................................................................ 27
Figure 8.3 USB Battery Charging Detection (2- pin) ........................................................................ 27
Figure 8.4 USB Battery Charging Detection (3 - pin) ....................................................................... 28
Figure 9.1: Data transfers using 7-bit addressing ........................................................................... 31
Figure 9.2: Data transfers with 7-bit and 10-bit addressing modes ................................................... 32
Figure 9.3: Checking the Data Available Count ............................................................................... 32
Figure 9.4: Flush data command .................................................................................................. 33
Figure 9.5: Reading the amount of data available ........................................................................... 33
Figure 9.6: Checking the USB State .............................................................................................. 34
Figure 9.7: Reading the Device ID ................................................................................................ 34
Figure 10.1: Simplified memory map for the FT201X ....................................................................... 38
Figure 10.2: Write EEPROM command sequence ............................................................................. 39
Figure 10.3: Read EEPROM command sequence ............................................................................. 40
Figure 11.1 SSOP-16 Package Dimensions ..................................................................................... 41
Figure 11.2 SSOP-16 Package Markings ......................................................................................... 42
Figure 11.3 QFN-16 Package Dimensions ....................................................................................... 43
Figure 11.4 QFN-16 Package Markings .......................................................................................... 44
Figure 11.5 FT201X Solder Reflow Profile ....................................................................................... 45
List of Tables
Table 3.1 Power and Ground .......................................................................................................... 7
Table 3.2 Common Function pins .................................................................................................... 7
Table 3.3 I2C Interface and CBUS Group (see note 1) ........................................................................ 8
Table 3.4 Power and Ground .......................................................................................................... 9
Table 3.5 Common Function pins .................................................................................................... 9
Table 3.6 Interface and CBUS Group (see note 1) ........................................................................... 10
Table 3.7 CBUS Configuration Control ........................................................................................... 12
Table 6.1 Absolute Maximum Ratings ............................................................................................ 16
Table 6.2 ESD and Latch-Up Specifications .................................................................................... 16
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Table 6.3 Operating Voltage and Current ....................................................................................... 17
Table 6.4 I/O Pin Characteristics VCCIO = +3.3V (except USB PHY pins) ........................................... 18
Table 6.5 I/O Pin Characteristics VCCIO = +2.5V (except USB PHY pins) ........................................... 19
Table 6.6 I/O Pin Characteristics VCCIO = +1.8V (except USB PHY pins) ........................................... 20
Table 6.7 USB I/O Pin (USBDP, USBDM) Characteristics .................................................................. 21
Table 6.8 MTP memory Characteristics .......................................................................................... 21
Table 6.9 Internal Clock Characteristics ......................................................................................... 21
Table 10.1 Default Internal MTP Memory Configuration.................................................................... 36
Table 11.1 Reflow Profile Parameter Values .................................................................................... 45
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FT201X USB I2C SLAVE IC Datasheet
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Appendix C - Revision History
Document Title: USB I2C SLAVE IC FT201X
Document Reference No.: FT_000627
Clearance No.: FTDI# 264
Product Page: http://www.ftdichip.com/FT-X.htm
Document Feedback: Send Feedback
Revision
Changes
Date
1.0
Initial Release
2012-02-09
1.1
Added USB compliance in section 1.3; Clarified MTP
Reliability in table 6.8; Edited Table 9.1: Edited I2C
address and changed Load VCP Driver to Disabled
2012-04-17
1.2
Added section 9 with details of USB and I2C
Interfacing; Added link to AN_201 (MTP Memory
Configuration) in section 10; Removed references to
LED signals on the CBUS pins as these are only
available on the UART members of the FT-X family;
Removed section 8.3 showing connection of the
Tx/Rx LEDs; Updated the CBUS defaults to reflect the
values used from Rev D onwards.
2012-08-15
1.3
Updated USA address; Updated TID; Updated front
page to clarify 5V tolerant
2013-02-14
1.4
Updated the QFN16 dimension in section 11.3
2014-07-25
1.5
Updated section 9.3 to correct the description of soft
reset; Added not to MTP section 10 regarding
checksum when programming over I2C.
2017-05-12
Mouser Electronics
Authorized Distributor
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