WT12-A-AI5IAP - Bluegiga Technologies

WT12

DATA SHEET

Friday, 08 November 2013

Version 3.0

Bluegiga Technologies Oy

Bluegiga Technologies assumes no responsibility for any errors which may appear in this manual.

Furthermore, Bluegiga Technologies reserves the right to alter the hardware, software, and/or specifications

detailed here at any time without notice and does not make any commitment to update the information

contained here. Bluegiga’s products are not authorized for use as critical components in life support devices

or systems.

The WRAP is a registered trademark of Bluegiga Technologies

The Bluetooth trademark is owned by the Bluetooth SIG Inc., USA and is licensed to Bluegiga Technologies.

All other trademarks listed herein are owned by their respective owners.

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Table of Contents

1 ORDERING INFORMATION .........................................................................................................................6

2 Block Diagram and Descriptions ...................................................................................................................7

3 Electrical Characteristics ...............................................................................................................................9

3.1 Absolute maximum ratings .....................................................................................................................9

3.2 Recommended operating conditions .....................................................................................................9

3.3 Terminal characteristics .........................................................................................................................9

3.4 Current consumption ........................................................................................................................... 10

3.5 Radio characteristics and general specifications ................................................................................ 11

3.6 Radio Characteristics – Basic Data Rate ............................................................................................ 12

3.6.1 Transmitter radio characteristics .................................................................................................. 12

3.6.2 Receiver radio characteristics ...................................................................................................... 13

3.7 Radio Characteristics – Enhanced Data Rate .................................................................................... 15

3.7.1 Transmitter radio characteristics .................................................................................................. 15

3.7.2 Receiver radio characteristics ...................................................................................................... 16

4 WT12 Pin Description ................................................................................................................................. 17

5 Physical Interfaces ..................................................................................................................................... 20

5.1 UART Interface .................................................................................................................................... 20

5.1.1 UART Configuration While RESET is Active ............................................................................... 21

5.1.2 UART Bypass Mode .................................................................................................................... 21

5.2 USB Interface ...................................................................................................................................... 23

5.2.1 USB Pull-Up Resistor ................................................................................................................... 23

5.2.2 Self Powered Mode ...................................................................................................................... 23

5.2.3 Bus Powered Mode ...................................................................................................................... 24

5.2.4 Suspend Current .......................................................................................................................... 24

5.2.5 Detach and Wake-Up Signaling ................................................................................................... 24

5.2.6 USB Driver ................................................................................................................................... 25

5.2.7 USB 1.1 Compliance .................................................................................................................... 25

5.2.8 USB 2.0 Compatibility .................................................................................................................. 25

5.3 SPI Interface ........................................................................................................................................ 26

5.4 PCM Interface ..................................................................................................................................... 27

5.4.1 PCM Interface Master/Slave ........................................................................................................ 27

5.4.2 Long Frame Sync ......................................................................................................................... 28

5.4.3 Short Frame Sync ........................................................................................................................ 28

5.4.4 Multi Slot Operation ..................................................................................................................... 29

5.4.5 GCI Interface ................................................................................................................................ 29

5.4.6 Slots and Sample Formats ........................................................................................................... 29

5.4.7 Additional Features .................................................................................................................... 30

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5.4.8 PCM Configuration ....................................................................................................................... 30

6 I/O Parallel Ports ........................................................................................................................................ 32

7 Software Stacks .......................................................................................................................................... 33

7.1 iWRAP Stack ....................................................................................................................................... 33

7.2 HCI Stack ............................................................................................................................................ 34

7.2.1 Standard functionality .................................................................................................................. 34

7.2.2 Extra functionality: ........................................................................................................................ 36

7.3 VM Stack ............................................................................................................................................. 37

7.4 Software Development ........................................................................................................................ 38

8 Enhanced Data Rate .................................................................................................................................. 39

8.1 Enhanced Data Rate Baseband .......................................................................................................... 39

8.2 ...................................................................................................... 39

8.3 8DQPSK .............................................................................................................................................. 39

9 Layout and Soldering Considerations ........................................................................................................ 41

9.1 Soldering recommendations ............................................................................................................... 41

9.2 Layout guidelines ................................................................................................................................ 41

10 WT12 physical dimensions ..................................................................................................................... 44

11 Package .................................................................................................................................................. 46

12 Certifications ........................................................................................................................................... 48

12.1 Bluetooth ...................................................................................................................................... 48

12.2 FCC and IC .................................................................................................................................. 48

12.3 CE ................................................................................................................................................ 50

12.4 Japan ........................................................................................................................................... 50

13 RoHS Statement with a List of Banned Materials ................................................................................... 51

14 Contact Information................................................................................................................................. 52

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WT12 Bluetooth module

DESCRIPTION

WT12 is a fully integrated Bluetooth 2.1 +

EDR, class 2 module combining

antenna, Bluetooth radio and an on-board

iWRAP Bluetooth stack. Bluegiga WT12

provides an ideal solution for developers that

want to quickly integrate Bluetooth wireless

technology to their design without

investing several months into Bluetooth radio

and stack development.

WT12 uses Bluegiga's

iWRAP Bluetooth stack, which is an

embedded Bluetooth stack implementing 13

different Bluetooth profiles and Apple iAP

connectivity. By using WT12 combined with

iWRAP Bluetooth stack and Bluegiga's

excellent technical support designers ensure

quick time to market, low development costs

and risk.

APPLICATIONS

 Industrial and M2M

 Mobile phone and tablet accessories

 Point-of-Sale devices

 Computer accessories

 Apple iOS accessories

KEY FEATURES

Radio features:

 Bluetooth v.2.1 + EDR

 Bluetooth class 2 radio

 Transmit power: +3 dBm

 Receiver sensitivity: -86 dBm

 Range: 30 meters line-of-sight

 Integrated chip antenna

Hardware features:

 UART and USB host interfaces

 802.11 co-existence interface

 6 software programmable IO pins

 Opertating voltage: 2.7V to 3.6V

 Temperature range: -40C to +85C

 Dimensions: 25.5 x 14.0 x 2.4 mm

Qualifications:

 Bluetooth

 CE

 FCC

 IC

 Japan and South-Korea

Figure 1: Physical outlook of WT12

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1 ORDERING INFORMATION

Internal chip antenna

iWRAP 5.0 firmware WT12-A-AI5

iWRAP 4.0 firmware WT12-A-AI4

iWRAP 3.0 firmware WT12-A-3

HCI firmware, BT2.1 + EDR WT12-A-HCI21

Custom firmware WT12-A-C (*

Table 1: Ordering information

*) Custom firmware means any standard firmware with custom parameters (like UART baud rate), custom firmware developer by

customer or custom firmware developed by Bluegiga for the customer.

To order custom firmware you must have a properly filled Custom Firmware Order From and unique ordering code issued by

Bluegiga.

Contact sales@bluegiga.com for more information.

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2 Block Diagram and Descriptions

Figure 2: Block Diagram of WT12

BlueCore04

BlueCore4 is a single chip Bluetooth solution which implements the Bluetooth radio transceiver and also

an on chip microcontroller. BlueCore4 implements Bluetooth® 2.1 + EDR (Enhanced Data Rate) and it

can deliver data rates up to 3 Mbps.

The microcontroller (MCU) on BlueCore04 acts as interrupt controller and event timer run the Bluetooth

software stack and control the radio and host interfaces. A 16-bit reduced instruction set computer

(RISC) microcontroller is used for low power consumption and efficient use of memory.

BlueCore04 has 48Kbytes of on-chip RAM is provided to support the RISC MCU and is shared between

the ring buffers used to hold voice/data for each active connection and the general purpose memory

required by the Bluetooth stack.

Crystal

The crystal oscillates at 26MHz.

Flash

Flash memory is used for storing the Bluetooth protocol stack and Virtual Machine applications. It can

also be used as an optional external RAM for memory intensive applications.

Balun / filter

Combined balun and filter changes the balanced input/output signal of the module to unbalanced signal

of the monopole antenna. The filter is a band pass filter (ISM band).

Matching

Antenna matching components match the antenna to 50 Ohms.

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Antenna

The antenna is ACX AT3216 chip antenna.

USB

This is a full speed Universal Serial Bus (USB) interface for communicating with other compatible digital

devices. WT12 acts as a USB peripheral, responding to requests from a Master host controller such as

a PC.

Synchronous Serial Interface

This is a synchronous serial port interface (SPI) for interfacing with other digital devices. The SPI port

can be used for system debugging. It can also be used for programming the Flash memory.

UART

This is a standard Universal Asynchronous Receiver Transmitter (UART) interface for communicating

with other serial devices.

Audio PCM Interface

The audio pulse code modulation (PCM) Interface supports continuous transmission and reception of

PCM encoded audio data over Bluetooth.

Programmable I/O

WT12 has a total of 6 digital programmable I/O terminals. These are controlled by firmware running on

the device.

Reset

This can be used to reset WT12.

802.11 Coexistence Interface

Dedicated hardware is provided to implement a variety of coexistence schemes. Channel skipping AFH

(Adaptive Frequency Hopping), priority signaling, channel signaling and host passing of channel

instructions are all supported. The features are configured in firmware. Since the details of some

methods are proprietary (e.g. Intel WCS) please contact Bluegiga Technologies for details.

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3 Electrical Characteristics

3.1 Absolute maximum ratings

Min Max Unit

Storage temperature -40 85 °C

Operating temperature -40 85 °C

Supply voltage -0,3 3,6 V

Terminal voltages -0,4 Vdd + 0,4 V

Output current from PIOS 35 mA

The module should not continuously run under these conditions. Exposure to absolute maximum rating conditions for extended periods of

time may affect reliability and cause permanent damage to the device.

Table 2: Absolute maximum ratings

3.2 Recommended operating conditions

Min Max Unit

Operating temperature -40 85 °C

Supply voltage

3,1 (1) 3,6 V

Terminal voltages 0 Vdd V

1) WT12 operates as low as 2,7 V supply voltage. However, to safely meet the USB specification for minimum voltage for USB data lines,

minimum of 3,1 V supply is required.

Table 3: Recommended operating conditions

3.3 Terminal characteristics

Min Typ Max Unit

I/O voltage levels

VIL input logic level low -0,4 - 0,8 V

VIH input logic level high 0,7Vdd - Vdd + 0,4 V

VOL output logic level low - - 0,2 V

VOH output logic level high Vdd - 0,2 - - V

Reset terminal

VTH,res threshold voltage 0,64 0,85 1,5 V

RIRES input resistance 220 k

CIRES input capacitance 220 nF

Input and tri-state current with

Strong pull-up -100 -40 -10



Strong pull-down 10 40 100



Weak pull-up -5 -1 -0,2



Weak pull-down 0,2 1 5



I/O pad leakage current -1 0 1



Vdd supply current

TX mode - - 70

RX mode - - 70 mA

Table 4: Terminal characteristics

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3.4 Current consumption

Test conditions: Room temperature, Vdd = 3,3 V, iWRAP firmware

OPERATION MODE

Peak

supply

current

AVG

supply

current

Unit Notes

Peak current at TX mode 70 -mA -

Peak current at RX mode 70 -mA -

IDLE - 3 mA Module is idle Default settings

IDLE, Deep Sleep ON - 1,2 mA Module is idle

IDLE, Deep Sleep ON

NOT visible, NOT

connectable

- 0,056 mA

Module is idle (Minimum consumption),

SET BT PAGEMODE 0 2000 1

INQUIRY - 44,7 mA Device discovery with INQUIRY command

NAME - 44,7 mA Name resolution

CALL - 44,7 mA CALL [ADDR] 1101 RFCOMM

CONNECT

Master - 6,2 mA No data was transmitted, Default settings

CONNECT

Slave - 22,4 mA No data was transmitted, Default settings

CONNECT + Sniff, Master - 4,7 mA Connected (SET BT SNIFF 40 20 1 8)

CONNECT + Sniff, Slave - 4,6 mA Connected (SET BT SNIFF 40 20 1 8)

CONNECT + sniff, Master - 2,3 mA

No data transmitted

(SET BT SNIFF 1000 20 1 8)

CONNECT + sniff, Slave - 2,3 mA

No data transmitted

(SET BT SNIFF 1000 20 1 8)

CONNECT + park, Master - 3,1 mA No data transmittedPark parameter 1000

CONNECT + park, Slave - 2,3 mA No data transmittedPark parameter 1000

DATA, Master - 31,5 mA Data transmitted @ 115200bps

DATA, Slave - 29,2 mA Data transmitted @ 115200bps

DATA + Sniff, Master - 19,6 mA

Data transmitted @ 115200bps

(SET BT SNIFF 40 20 1 8)

DATA + Sniff, Slave - 22,6 mA

Data transmitted @ 115200bps

(SET BT SNIFF 40 20 1 8)

DATA + Sniff, Master - 3,9 mA

Data transmitted

(SET BT SNIFF 1000 20 1 8)

Table 5: Current consumption

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3.5 Radio characteristics and general specifications

Note

Operating

frequency range

ISM Band

Lower quard

band

Upper quard

band

Carrier frequency

f = 2402 + k,

k = 0...78

Modulation

method

Hopping

GFSK:

Asynchronous, 723.2 kbps / 57.6 kbps

Synchronous: 433.9 kbps / 433.9 kbps

P/4

DQPSK:

Asynchronous, 1448.5 kbps / 115.2 kbps

Synchronous: 869.7 kbps / 869.7 kbps

8DQPSK:

Asynchronous, 2178.1 kbps / 177.2 kbps

Synchronous: 1306.9 kbps / 1306.9 kbps

Receiving signal

range

Typical

condition

Receiver IF

frequency

Center

frequency

Min -11 ... -9 dBm

Max +1 ... +3 dBm

RF input

impedance

Compliance

USB specification

Transmission

power

50 

Maximum data

rate

Specification

(2400 ... 2483,5) MHz

2 MHz

3,5 MHz

2402 MHz ... 2480 MHz

GFSK (1 Mbps)

P/4 DQPSK (2Mbps)

1600 hops/s, 1 MHz channel space

Bluetooth specification, version 2.0 + EDR

USB specification, version 1.1 (USB 2.0 compliant)

-82 to -20 dBm

1.5 MHz

Table 6: Radio characteristics and general specifications

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3.6 Radio Characteristics – Basic Data Rate

3.6.1 Transmitter radio characteristics

WT12 meets the Bluetooth v2.1 + EDR specification between -40°C and +85°C. TX output is guaranteed to be unconditionally

stable over the guaranteed temperature range.

Measurement conditions: T = 20C, Vdd = 3,3V

Item Typical value Bluetooth specification Unit

Maximum output power1,2 +2.5 -6 to 4 3dBm

Variation in RF power over

temperature range with

compensation enabled4

1.5 -dB

Variation in RF power over

temperature range with

compensation disabled4

2.0 -dB

RF power control range 35 16 dB

RF power range control

resolution5

0.5 -dB

20dB bandwidth for modulated

carrier

780  1000 kHz

Adjacent channel transmit power

F = F0 ± 2MHz6,7

-40  20 dBm

Adjacent channel transmit power

F = F0 ± 3MHz6,7

-45  -40 dBm

Adjacent channel transmit power

F = F0 ± > 3MHz6,7

-50  -40 dBm

f1avg Maximum Modulation 165 140<f1avg<175 kHz

f2max Maximum Modulation 150 115 kHz

f1avg / f2avg 0.97 0.80 -

Initial carrier frequency tolerance 6  75 kHz

Drift Rate 8  20 kHz/50s

Drift (single slot packet) 7  25 kHz

Drift (five slot packet) 9  40 kHz

2nd Harmonic content -65  -30 dBm

3rd Harmonic content -45  -30 dBm

Table 7: Transmitter radio characteristics at basic data rate and temperature 20C

Notes:

1. WT12 firmware maintains the transmit power to be within the Bluetooth v2.1 + EDR specification limits.

2. Measurement made using a PSKEY_LC_MAX_TX_POWER setting corresponds to a PSKEY_LC_POWER_TABLE

power table entry of 63.

3. Class 2 RF-transmit power range, Bluetooth v2.1 + EDR specification.

4. To some extent these parameters are dependent on the matching circuit used, and its behavior over temperature.

Therefore these parameters may be beyond CSR’s direct control.

5. Resolution guaranteed over the range -5dB to -25dB relative to maximum power for TX Level >20.

6. Measured at F0= 2441MHz.

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7. Up to three exceptions are allowed in the Bluetooth v2.1 + EDR specification. WT12s guaranteed to meet the ACP

performance as specified by the Bluetooth v2.1 + EDR specification.

Frequency (GHz) Typ Unit Cellular band

0.869 – 0.8941-145 GSM 850

0.869 – 0.8942-145 CDMA 850

0.925 – 0.9601 -145 GSM 900

1.570 – 1.5803-145 GPS

1.805 – 1.8801-145

GSM 1800 / DCS

1800

1.930 – 1.9904 -145 PSC 1900

1.930 – 1.9901 -145 GSM 1900

1.930 – 1.9902 -145 CDMA 1900

2.110 – 2.1702 -142 W-CDMA 2000

2.110 – 2.1702-144 W-CDMA 2000

Emitted power in

cellular bands

measured at the

unbalanced port of

the balun.

Output power 4dBm

dBm/kHz

Table 8: Transmitter radio characteristics at basic data rate and temperature 20C

Notes:

1. Integrated in 200kHz bandwidth and then normalized to a 1Hz bandwidth.

2. Integrated in 1.2MHz bandwidth and then normalized to a 1Hz bandwidth.

3. Integrated in 1MHz bandwidth. and then normalized to a 1Hz bandwidth.

4. Integrated in 30kHz bandwidth and then normalized to a 1Hz bandwidth.

5. Integrated in 5MHz bandwidth and then normalized to a 1Hz bandwidth.

3.6.2 Receiver radio characteristics

Measurement conditions: T = 20C, Vdd = 3,3V

Frequency

(GHz)

Typ

Bluetooth

specification

Unit

2.402 -84

2.441 -84

2.480 -84

10 -20 dBm

Sensitivity at 0.1% BER

for all packet types

Maximum received signal at 0.1% BER

dBm

 75

Table 9: Receiver radio characteristics at basic data rate and temperature 20C

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Frequency

(GHz)

Typ

Bluetooth

specification

Unit

30-2000 TBD -10

2000-2400 TBD -27

2500-3000 TBD -27

3000-3300 TBD -27

6 11 dB

-5  0 dB

-4  0 dB

-38  -30 dB

-23  -20 dB

-45  -40 dB

-44  -40 dB

-22  9 dB

-30 -39 dBm

TBD - dBm/Hz

Adjacent channel selectivity C/I F=FImage

1,2

Maximum level of intermodulation interferers3

Spurious output level4

dBm

Adjacent channel selectivity C/I F=F0 + 2 MHz1,2

Adjacent channel selectivity C/I F=F0 - 2 MHz1,2

Adjacent channel selectivity C/I F=F0 + 3 MHz1,2

Adjacent channel selectivity C/I F=F0 - 5 MHz1,2

Continuous power required to block

Bluetooth reception (for sensitivity of -

67dBm with 0.1% BER) measured at

the unbalanced port of the balun.

C/I co-channel

Adjacent channel selectivity C/I F=F0 + 1MHz1,2

Adjacent channel selectivity C/I F=F0 - 1MHz1,2

Table 10: Receiver radio characteristics at basic data rate and temperature 20C

Notes:

1. Up to five exceptions are allowed in the Bluetooth v2.1 + EDR specification. BlueCore4 is guaranteed to meet the

C/I performance as specified by the Bluetooth v2.1 + EDR specification.

2. Measured at F = 2441MHz

3. Measured at f1-f2 = 5MHz. Measurement is performed in accordance with Bluetooth RF test RCV/CA/05/c. i.e.

wanted signal at -64dBm

4. Measured at the unbalanced port of the balun. Integrated in 100kHz bandwidth and then normalized to 1Hz. Actual

figure is typically below TBD dBm/Hz except for peaks of -52dBm in band at 2.4GHz and d80dBm at 3.2GHz

Frequency

(GHz)

Typ Unit Cellular band

0.824 – 0.849 2.0 GSM 850

0.824 – 0.849 TBD CDMA

0.880 – 0.915 5.0 GSM 900

1.710 – 1.785 4.0 GSM 1800 / DCS 1800

1.710 – 1.785 3.0 GSM 1900 / PCS 1900

1.850 – 1.910 TBD CDMA 1900

1.920 – 1.980 TBD W-CDMA 2000

0.824 – 0.849 -10 GSM 850

0.824 – 0.849 TBD CDMA

0.880 – 0.915 -10 GSM 900

1.710 – 1.785 -9 GSM 1800 / DCS 1800

1.850 – 1.910 -9 GSM 1900 / PCS 1900

1.850 – 1.910 TBD CDMA 1900

1.920 – 1.980 TBD W-CDMA 2000

Emitted power in cellular

bands required to block

Bluetooth reception (for

sensitivity of -67dBm with

0.1% BER) measured at the

unbalanced port of the

balun.

Continuous power in cellular

bands required to block

Bluetooth reception (for

sensitivity of-72dBm with

0.1% BER) measured at the

unbalanced port of the

balun.

dBm

Table 11: Receiver radio characteristics at basic data rate and temperature 20C

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3.7 Radio Characteristics – Enhanced Data Rate

3.7.1 Transmitter radio characteristics

Measurement conditions: T = 20C, Vdd = 3,3V

Typ Bluetooth specification Unit

+1 -6 to 42dBm

-1 -4 to 1 dB

3 10 kHz

RMS DEV -  135%

99% DEV -  205%

Peak DEVM -  255%

Modulation

accuracy3,4

Carrier frequency stability3

Relative transmit power3

Maximum output power1

Table 12: Transmitter radio characteristics at enhanced data rate and temperature 20C

Notes:

1. Results shown are referenced to input of the RF balun.

2. WT12 firmware maintains the transmit power to be within the Bluetooth v2.1 + EDR specification limits

3. Class 2 RF transmit power range, Bluetooth v2.1 + EDR specification

4. Measurements methods are in accordance with the EDR RF Test Specification v2.1.E.2

5. Modulation accuracy utilizes differential error vector magnitude (DEVM) with tracking of the carrier frequency drift.

6. The Bluetooth specification values are for 8DPSK modulation (values for the S/4 DQPSK modulation are less stringent)

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3.7.2 Receiver radio characteristics

Measurement conditions: T = 20C, Vdd = 3,3V

Modulation Typ

Bluetooth

specification

Unit

/4 DQPSK -87  -70

8DQPSK -79  -70

/4 DQPSK -7 -20

8DQPSK -7 -20

/4 DQPSK +11  13

8DQPSK +19  21

/4 DQPSK -8  0

8DQPSK -2  5

/4 DQPSK -8  0

8DQPSK -2  5

/4 DQPSK -35  -30

8DQPSK -35  -25

/4 DQPSK -23  -20

8DQPSK -19  -13

/4 DQPSK -43  -40

8DQPSK -40  -33

/4 DQPSK -43  -40

8DQPSK -38  -33

/4 DQPSK -17  -7

8DQPSK -11  0

C/I co-channel at 0.1% BER1

Adjacent channel selectivity

C/I F = F0 + 1MHz1,2,3

Adjacent channel selectivity

C/I F = F0 - 5MHz1,2,3

Adjacent channel selectivity

C/I F = FImage

1,2,3

dBm

Adjacent channel selectivity

C/I F = F0 - 1MHz1,2,3

Adjacent channel selectivity

C/I F=F0 + 2MHz1,2,3

Adjacent channel selectivity

C/I F = F0 - 2MHz1,2,3

Adjacent channel selectivity

C/I F = F0 + 3MHz1,2,3

Sensitivity at 0.1% BER for

all packet types1

Maximum received signal at

0.1% BER1

Table 13: Receiver radio characteristics at enhanced data rate and temperature 20C

Notes:

1. Results shown are referenced to input of the RF balun

2. Measurements methods are in accordance with the EDR RF Test Specification v2.1.E.2

3. Up to five exceptions are allowed in EDR RF Test Specification v2.1.E.2. WT12 is guaranteed to meet the C/I

performance as specified by the EDR RF Test Specification v2.1.E.2.

4. Measured at F0 = 2405MHz, 2441MHz, 2477MHz

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4 WT12 Pin Description

WT12

293031

GND

VDD

PIO2

PIO3

NRTS

RXD

PCMO

USB_D+

USB_D-

NCTS

PCMI

PCMC

PCMS

GND

TXD

PIO5

MOSI

MISO

SCLK

NCSB

PIO4

PIO7

PIO6

RES

VDD

GND

GND GNDRF

Figure 3: WT12 connection diagram

GND (pins 1, 14, 15, 28, 29 and 31)

Connect GND pins to the ground plane of PCB.

VDD (pins 2 and 16)

3.3 V supply voltage connection. WT12 has an internal decoupling capacitor and LC filter to block high

frequency disturbances. Thus external filtering is usually not needed. It is however recommended to

leave an option for an external high Q 10pF decoupling capacitor in case EMC problems arise.

RES (pin 17)

The RESET pin is an active high reset and is internally filtered using the internal low frequency clock

oscillator. A reset will be performed between 1.5 and 4.0ms following RESET being active. It is

recommended that RESET be applied for a period greater than 5ms.

WT12 has an internal reset circuitry, which keeps reset pin active until supply voltage has reached

stability in the start up. This ensures that supply for the flash memory inside the WT12 will reach stability

before BC4 chip fetches instructions from it. Schematic of the reset circuitry is shown in figure 4. Rising

supply voltage charges the capacitor, which will activate the reset of WT12. The capacitor discharges

through 220 k resistor, which eventually deactivates the reset. Time constant of the RC circuitry is set

such that the supply voltage is safely stabilized before reset deactivates. Pull-up or pull-down resistor

should not be connected to the reset pin to ensure proper star up of WT12.

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Figure 4: WT12 internal reset circuitry

PIO2 – PIO7 (pins 3, 4, 18, 19, 20 and 25)

Programmable digital I/O lines. All PIO lines can be configured through software to have either weak or

strong pull-ups or pull-downs. Configuration for each PIO line depends on the application. See section

10 “I/O parallel ports” for detailed descriptions for each terminal. Default configuration for all of the PIO

lines is input with weak internal pull-down.

NC (pin 27)

This pin is internally connected to PIO1.

NRTS (pin 5)

CMOS output with weak internal pull-up. Can be used to implement RS232 hardware flow control where

RTS (request to send) is active low indicator. UART interface requires external RS232 transceiver chip.

NCTS (pin 10)

CMOS input with weak internal pull-down. Can be used to implement RS232 hardware flow control

where CTS (clear to send) is active low indicator. UART interface requires external RS232 transceiver

chip.

RXD (pin 6)

CMOS input with weak internal pull-down. RXD is used to implement UART data transfer from another

device to WT12. UART interface requires external RS232 transceiver chip.

TXD (pin 26)

CMOS output with weak internal pull-up. TXD is used to implement UART data transfer from WT12 to

another device. UART interface requires external RS232 transceiver chip.

PCMO (pin 7)

CMOS output with weak internal pull-down. Used in PCM (pulse code modulation) interface to transmit

digitized audio.

PCMI (pin 11)

CMOS input with weak internal pull-down. Used in PCM interface to receive digitized audio.

PCMC (pin 12)

Bi-directional synchronous data clock signal pin with weak internal pull-down. PCMC is used in PCM

interface to transmit or receive CLK signal. When configured as a master, WT12 generates clock signal

for the PCM interface. When configured as a slave PCMC is an input and receives the clock signal from

another device.

PCMS (pin 13)

Bi-directional synchronous data strobe with weak internal pull-down. When configured as a master,

WT12 generates SYNC signal for the PCM interface. When configured as a slave PCMS is an input and

receives the SYNC signal from another device.

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USB_D+ (pin 8)

Bi-directional USB data line with a selectable internal 1.5 k pull-up implemented as a current source

(compliant with USB specification v1.2) External series resistor is required to match the connection to

the characteristic impedance of the USB cable.

USB_D- (pin 9)

Bi-directional USB data line. External series resistor is required to match the connection to the

characteristic impedance of the USB cable.

NCSB (pin 21)

CMOS input with weak internal pull-up. Active low chip select for SPI (serial peripheral interface).

SCLK (pin 22)

CMOS input for the SPI clock signal with weak internal pull-down. WT12 is the slave and receives the

clock signal from the device operating as a master.

MISO (pin 23)

SPI data output with weak internal pull-down.

MOSI (pin 24)

SPI data input with weak internal pull-down.

RF (pin 30)

Connect external RF-transceiver antenna to this pin when chip antenna is not in use.

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5 Physical Interfaces

5.1 UART Interface

WT12 Universal Asynchronous Receiver Transmitter (UART) interface provides a simple mechanism for

communicating with other serial devices using the RS232 standard. The UART interface of WT12 uses

voltage levels of 0 to Vdd and thus external transceiver IC is required to meet the voltage level

specifications of UART.

UART_TX

UART_RX

UART_RTS

UART_CTS

WT12

Figure 5: WT12 UART interface

Four signals are used to implement the UART function, as shown in Figure 6. When WT12 is connected

to another digital device, UART_RX and UART_TX transfer data between the two devices. The

remaining two signals, UART_CTS and UART_RTS, can be used to implement RS232 hardware flow

control where both are active low indicators. DTR, DSR and DCD signals can be implemented using

PIO terminals of WT12. All UART connections are implemented using CMOS technology and have

signaling levels of 0V and VDD.

In order to communicate with the UART at its maximum data rate using a standard PC, an accelerated

serial port adapter card is required for the PC.

Parameter

Possible values

Baud

rate

Minimum

1200 baud (≤2%Error)

9600 baud (≤1%Error)

Maximum

3.0Mbaud (≤1%Error)

Flow control

RTS/CTS, none

Parity

None, Odd, Even

Number of stop bits

1 or 2

Bits per channel

Table 14: Possible UART settings

The UART interface is capable of resetting WT12 upon reception of a break signal. A Break is identified

by a continuous logic low (0V) on the UART_RX terminal, as shown in Figure 7. If tBRK is longer than the

value, defined by the PS Key PSKEY_HOST_IO_UART_RESET_TIMEOUT, (0x1a4), a reset will occur.

This feature allows a host to initialize the system to a known state. Also, WT12 can emit a Break

character that may be used to wake the Host.

Since UART_RX terminal includes weak internal pull-down, it can’t be left open unless disabling UART

interface using PS_KEY settings. If UART is not disabled, a pull-up resistor has to be connected to

UART_RX. UART interface requires external RS232 transceiver, which usually includes the required

pull-up.

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tBRK

UART_RX

Figure 6: Break signal

Note

Table 15 shows a list of commonly used Baud rates and their associated values for the Persistent Store

Key PSKEY_UART_BAUD_RATE (0x204). There is no requirement to use these standard values. Any

Baud rate within the supported range can be set in the Persistent Store Key according to the formula in

Equation below.

Baud Rate = PSKEY_UART_BAUD_RATE

0.004096

Figure 7: Baud rate calculation formula

Hex Dec

1200 0x0005 51.73%

2400

0x000a 10 1.73%

4800

0x0014 20 1.73%

9600

0x0027 39 -0.82%

19200

0x004f 79 0.45%

38400

0x009d 157 -0.18%

57600

0x00ec 263 0.03%

76800

0x013b 315 0.14%

115200

0x01d8 472 0.03%

230400

0x03b0 944 0.03%

460800

0x075f 1887 -0.02%

921600

0x0ebf 3775 0.00%

1382400

0x161e 5662 -0.01%

1843200

0x1d7e 7550 0.00%

2765800 0x2c3d 11325 0.00%

Persistent store values

Baud rate

Error

Table 15: UART baud rates and error values

5.1.1 UART Configuration While RESET is Active

The UART interface for WT12 while the chip is being held in reset is tri-state. This will allow the user to

daisy chain devices onto the physical UART bus. The constraint on this method is that any devices

connected to this bus must tri-state when WT12reset is de-asserted and the firmware begins to run.

5.1.2 UART Bypass Mode

Alternatively, for devices that do not tri-state the UART bus, the UART bypass mode on WT12 can be

used. The default state of WT12 after reset is de-asserted, this is for the host UART bus to be

connected to the WT12 UART, thereby allowing communication to WT12 via the UART.

In order to apply the UART bypass mode, a BCCMD command will be issued to WT12 upon this, it will

switch the bypass to PIO[7:4] as shown in Figure 9. Once the bypass mode has been invoked, WT12

will enter the deep sleep state indefinitely.

In order to re-establish communication with WT12, the chip must be reset so that the default

configuration takes affect.

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It is important for the host to ensure a clean Bluetooth disconnection of any active links before the

bypass mode is invoked. Therefore it is not possible to have active Bluetooth links while operating the

bypass mode.

The current consumption for a device in UART Bypass Mode is equal to the values quoted for a device

in standby mode.

WT12

Host

processor

Test

interface

RXD

CTS

RTS

TXD

Another

device

RTS

CTS

UART_TX

UART_RTS

UART_CTS

UART_RX

RESET

PIO5

PIO6

PIO7

PIO4

UART

Figure 8: UART bypass mode

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5.2 USB Interface

WT12 USB devices contain a full speed (12Mbits/s) USB interface that is capable of driving a USB

cable directly. No external USB transceiver is required. To match the connection to the characteristic

impedance of the USB cable, series resistors must be included to both of the signal lines. These should

be of 1% tolerance and the value required may vary between 0 and 20 ohm with 10 ohm being nominal.

The resistors should be placed close to the USB pins of the module in order to avoid reflections. The

module has internally 22 ohm resistors in series. The total input impedance seen by the cable is

affected by the IC characteristics, track layout and the connector. The cable impedance is

approximately 40 ohm.

The device operates as a USB peripheral, responding to requests from a master host controller such as

a PC. Both the OHCI and the UHCI standards are supported. The set of USB endpoints implemented

can behave as specified in the USB section of the Bluetooth v2.1 + EDR specification or alternatively

can appear as a set of endpoint appropriate to USB audio devices such as speakers.

As USB is a Master/Slave oriented system (in common with other USB peripherals), WT12 only

supports USB Slave operation.

5.2.1 USB Pull-Up Resistor

WT12 features an internal USB pull-up resistor. This pulls the USB_DP pin weakly high when WT12 is

ready to enumerate. It signals to the PC that it is a full speed (12Mbit/s) USB device.

The USB internal pull-up is implemented as a current source, and is compliant with Section 7.1.5 of the

USB specification v1.2. The internal pull-up pulls USB_D+ high to at least 2.8V when loaded with a

15k +/-5% pull-down resistor (in the hub/host). This presents a Therein resistance to the host of at

least 900. Alternatively, an external 1.5k pull-up resistor can be placed between a PIO line and D+

on the USB cable. The firmware must be alerted to which mode is used by setting PS Key

PSKEY_USB_PIO_PULLUP appropriately. The default setting uses the internal pull-up resistor.

5.2.2 Self Powered Mode

In self powered mode, the circuit is powered from its own power supply and not from the VBUS (5V) line

of the USB cable. It draws only a small leakage current (below 0.5mA) from VBUS on the USB cable.

This is the easier mode for which to design for, as the design is not limited by the power that can be

drawn from the USB hub or root port. However, it requires that VBUS be connected to WT12 via a

voltage devider (Rvb1 and Rvb2), so WT12 can detect when VBUS is powered up. Voltage divider is

essential to drop the 5V voltage at the VBUS to 3,3V expected at the USB interface of WT12. WT12 will

not pull USB_DP high when VBUS is off.

Self powered USB designs (powered from a battery or PSU) must ensure that a PIO line is allocated for

USB pull-up purposes. A 1.5K 5% pull-up resistor between USB_DP and the selected PIO line should

be fitted to the design. Failure to fit this resistor may result in the design failing to be USB compliant in

self powered mode. The internal pull-up in WT12 is only suitable for bus powered USB devices i.e.

dongles.

PIO

USB_D+

USB_D-

USB_ON

R =1.5k

Rvb1

WT12

Rvb2

Figure 9: USB in self powered mode

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The terminal marked USB_ON can be any free PIO pin. The PIO pin selected must be registered by

setting PSKEY_USB_PIO_VBUS to the corresponding pin number. In self powered mode

PSKEY_USB_PIO_PULLUP must be set to match with the PIO selected.

Note:

USB_ON is shared with WT12 PIO terminals (PIO2-PIO7).

5.2.3 Bus Powered Mode

In bus powered mode the application circuit draws its current from the 5V VBUS supply on the USB

cable. WT12 negotiates with the PC during the USB enumeration stage about how much current it is

allowed to consume.

For WT12 Bluetooth applications, it is recommended that the regulator used to derive 3.3V from VBUS

is rated at 100mA average current and should be able to handle peaks of 120mA without fold back or

limiting. In bus powered mode, WT12 requests 100mA during enumeration.

When selecting a regulator, be aware that VBUS may go as low as 4.4V. The inrush current (when

charging reservoir and supply decoupling capacitors) is limited by the USB specification (see USB

specification v1.1, Section 7.2.4.1). Some applications may require soft start circuitry to limit inrush

current if more than 10pF is present between VBUS and GND.

The 5V VBUS line emerging from a PC is often electrically noisy. As well as regulation down to 3.3V,

applications should include careful filtering of the 5V line to attenuate noise that is above the voltage

regulator bandwidth.

In bus powered mode PSKEY_USB_PIO_PULLUP must be set to 16 for internal pull-up (default

configuration in WT12).

USB_D+

USB_D-

USB_ON

Voltage

regulator

WT12

VBUS

GND

Figure 10: USB in bus powered mode

5.2.4 Suspend Current

All USB devices must permit the USB controller to place them in a USB Suspend mode. While in USB

Suspend, bus powered devices must not draw more than 0.5mA from USB VBUS (self powered devices

may draw more than 0.5mA from their own supply). This current draw requirement prevents operation of

the radio by bus powered devices during USB Suspend.

The voltage regulator circuit itself should draw only a small quiescent current (typically less than 100uA)

to ensure adherence to the suspend current requirement of the USB specification. This is not normally a

problem with modern regulators. Ensure that external LEDs and/or amplifiers can be turned off by

WT12. The entire circuit must be able to enter the suspend mode. (For more details on USB Suspend,

see separate CSR documentation).

5.2.5 Detach and Wake-Up Signaling

WT12 can provide out-of-band signaling to a host controller by using the control lines called

‘USB_DETACH’ and ‘USB_WAKE_UP’. These are outside the USB specification (no wires exist for

them inside the USB cable), but can be useful when embedding WT12 into a circuit where no external

USB is visible to the user. Both control lines are shared with PIO pins and can be assigned to any PIO

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pin by setting the PS Keys PSKEY_USB_PIO_DETACH and PSKEY_USB_PIO_WAKEUP to the

selected PIO number.

USB_DETACH is an input which, when asserted high, causes WT12 to put USB_D- and USB_D+ in

high impedance state and turned off the pull-up resistor on D+. This detaches the device from the bus

and is logically equivalent to unplugging the device. When USB_DETACH is taken low, WT12 will

connect back to USB and await enumeration by the USB host.

USB_WAKE_UP is an active high output (used only when USB_DETACH is active) to wake up the host

and allow USB communication to recommence. It replaces the function of the software USB WAKE_UP

message (which runs over the USB cable), and cannot be sent while WT12 is effectively disconnected

from the bus.

USB_WAKE_UP

USB_DETACH

Port_Imbedance

USB_DPUSB_DN

USB_PULL_UP

10ms max

10ms max 10ms max

No max

Disconnected

Figure 11: USB_DETACH and USB_WAKE_UP Signal

5.2.6 USB Driver

A USB Bluetooth device driver is required to provide a software interface between WT12 and Bluetooth

software running on the host computer. Suitable drivers are available from www.bluegiga.com/techforum/.

5.2.7 USB 1.1 Compliance

WT12 is qualified to the USB specification v1.1, details of which are available from http://www.usb.org.

The specification contains valuable information on aspects such as PCB track impedance, supply inrush

current and product labeling.

Although WT12 meets the USB specification, Bluegiga Technologies cannot guarantee that an

application circuit designed around the module is USB compliant. The choice of application circuit,

component choice and PCB layout all affect USB signal quality and electrical characteristics. The

information in this document is intended as a guide and should be read in association with the USB

specification, with particular attention being given to Chapter 7. Independent USB qualification must be

sought before an application is deemed USB compliant and can bear the USB logo. Such qualification

can be obtained from a USB plug fest or from an independent USB test house.

Terminals USB_D+ and USB_D- adhere to the USB specification 2.0 (Chapter 7) electrical

requirements.

5.2.8 USB 2.0 Compatibility

WT12 is compatible with USB v2.0 host controllers; under these circumstances the two ends agree the

mutually acceptable rate of 12Mbits/s according to the USB v2.0 specification.

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5.3 SPI Interface

The synchronous serial port interface (SPI) is for interfacing with other digital devices. The SPI port can

be used for system debugging. It can also be used for programming the Flash memory. SPI interface is

connected using the MOSI, MISO, CSB and CLK pins.

The module operates as a slave and thus MISO is an output of the module. MISO is not in high-

impedance state when CSB is pulled high. Instead, the module outputs 0 if the processor is running and

1 if it is stopped. Thus WT12 should not be connected in a multi-slave arrangement by simple parallel

connection of slave MISO lines.

The SPI interface cannot be used for application purposes, but is dedicated for debugging and firmware

updates.

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5.4 PCM Interface

Pulse Code Modulation (PCM) is a standard method used to digitize audio (particularly voice) patterns

for transmission over digital communication channels. Through its PCM interface, WT12 has hardware

support for continual transmission and reception of PCM data, thus reducing processor overhead for

wireless headset applications. WT12 offers a bi directional digital audio interface that routes directly into

the baseband layer of the on chip firmware. It does not pass through the HCI protocol layer.

Hardware on WT12 allows the data to be sent to and received from a SCO connection. Up to three SCO

connections can be supported by the PCM interface at any one time.

WT12 can operate as the PCM interface Master generating an output clock of 128, 256 or 512kHz.

When configured as PCM interface slave it can operate with an input clock up to 2048kHz. WT12 is

compatible with a variety of clock formats, including Long Frame Sync, Short Frame Sync and GCI

timing environments.

It supports 13 or 16-bit linear, 8-bit -law or A-law companded sample formats at 8ksamples/s and can

receive and transmit on any selection of three of the first four slots following PCM_SYNC. The PCM

configuration options are enabled by setting the PS Key PS KEY_PCM_CONFIG32 (0x1b3). WT12

interfaces directly to PCM audio devices including the following:

 Qualcomm MSM 3000 series and MSM 5000 series CDMA baseband devices

 OKI MSM7705 four channel A-law and -law CODEC

 Motorola MC145481 8-bit A-law and -law CODEC

 Motorola MC145483 13-bit linear CODEC

 STW 5093 and 5094 14-bit linear CODECs

 BlueCore4-External is also compatible with the Motorola SSI™ interface

5.4.1 PCM Interface Master/Slave

When configured as the Master of the PCM interface, WT12 generates PCM_CLK and PCM_SYNC.

PCM_OUT

PCM_IN

PCM_CLK

PCM_SYNC 8kHz

128/256/512 kHz

WT12

Figure 12: WT12 as PCM master

When configured as the Slave of the PCM interface, WT12 accepts PCM_CLK and PCM_SYNC.

PCM_CLK rates up to 2048kHz are accepted.

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PCM_OUT

PCM_IN

PCM_CLK

PCM_SYNC 8kHz

Up to 2048kHz

WT12

Figure 13: WT12 as PCM slave

5.4.2 Long Frame Sync

Long Frame Sync is the name given to a clocking format that controls the transfer of PCM data words or

samples. In Long Frame Sync, the rising edge of PCM_SYNC indicates the start of the PCM word.

When WT12 is configured as PCM Master, generating PCM_SYNC and PCM_CLK, then PCM_SYNC

is 8-bits long. When BlueCore4-External is configured as PCM Slave, PCM_SYNC may be from two

consecutive falling edges of PCM_CLK to half the PCM_SYNC rate, i.e. 62.5s long.

WT12 samples PCM_IN on the falling edge of PCM_CLK and transmits PCM_OUT on the rising edge.

PCM_OUT may be configured to be high impedance on the falling edge of PCM_CLK in the LSB

position or on the rising edge.

12 3 4 5 6 7 8PCM_OUT

PCM_CLK

PCM_SYNC

12 3 4 5 6 7 8

undefined undefined

PCM_IN

Figure 14: Long frame sync (shown with 8-bit Companded Sample)

5.4.3 Short Frame Sync

In Short Frame Sync the falling edge of PCM_SYNC indicates the start of the PCM word. PCM_SYNC

is always one clock cycle long.

12 3 4 5 6 7 8PCM_OUT

PCM_CLK

PCM_SYNC

12 3 4 5 6 7 8

undefined

PCM_IN

910 11 12 13 14 15 16

910 11 12 13 14 15 16 undefined

Figure 15: Short frame sync (shown with 16-bit Companded Sample)

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As with Long Frame Sync, WT12 samples PCM_IN on the falling edge of PCM_CLK and transmits

PCM_OUT on the rising edge. PCM_OUT may be configured to be high impedance on the falling edge

of PCM_CLK in the LSB position or on the rising edge.

5.4.4 Multi Slot Operation

More than one SCO connection over the PCM interface is supported using multiple slots. Up to three

SCO connections can be carried over any of the first four slots.

12 3 4 5 6 7 8PCM_OUT

PCM_CLK

LONG_PCM_SYNC

12 3 4 5 6 7 8

undefined undefined

PCM_IN

SHORT_PCM_SYNC

Figure 16: Multi Slot Operation with Two Slots and 8-bit Companded Samples

5.4.5 GCI Interface

WT12 is compatible with the General Circuit Interface, a standard synchronous 2B+D ISDN timing

interface. The two 64Kbps B channels can be accessed when this mode is configured.

12 3 4 5 6 7 8PCM_OUT

PCM_CLK

PCM_SYNC

12 3 4 5 6 7 8

undefined

PCM_IN

1 2 3 4 56 7 8

1 2 3 4 56 7 8 undefined

Figure 17: GCI Interface

The start of frame is indicated by the rising edge of PCM_SYNC and runs at 8kHz. With WT12 in Slave

mode, the frequency of PCM_CLK can be up to 4.096MHz.

5.4.6 Slots and Sample Formats

WT12 can receive and transmit on any selection of the first four slots following each sync pulse. Slot

durations can be either 8 or 16 clock cycles. Duration’s of 8 clock cycles may only be used with 8-bit

sample formats. Durations of 16 clocks may be used with 8, 13 or 16-bit sample formats.

WT12 supports 13-bit linear, 16-bit linear and 8-bit -law or A-law sample formats. The sample rate is

8ksamples/s. The bit order may be little or big Endian. When 16-bit slots are used, the 3 or 8 unused

bits in each slot may be filled with sign extension, padded with zeros or a programmable 3-bit audio

attenuation compatible with some Motorola CODECs.

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PCM_OUT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Sign extension

8-bit sample

Figure 18: 16-bit slot with 8-bit companded sample and sign extension selected

PCM_OUT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

8-bit sample

Zeros padding

Figure 19: 16-bit slot with 8-bit companded sample and zeros padding selected

PCM_OUT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

3-bit sign

extension

13-bit sample

Figure 20: 16-bit slot with 13-bit linear sample and sign extension selected

PCM_OUT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Audio gain

13-bit sample

Figure 21: 16-bit slot with 13-bit linear sample and audio gain selected

5.4.7 Additional Features

WT12 has a mute facility that forces PCM_OUT to be 0. In Master mode, PCM_SYNC may also be

forced to 0 while keeping PCM_CLK running which some CODECS use to control power down.

5.4.8 PCM Configuration

The PCM configuration is set using two PS Keys, PSKEY_PCM_CONFIG32 and

PSKEY_PCM_LOW_JITTER_CONFIG. The following tables detail these PS Keys. The default for

PSKEY_PCM_CONFIG32 key is 0x00800000 i.e. first slot following sync is active, 13-bit linear voice

format, long frame sync and interface master generating 256kHz PCM_CLK from 4MHz internal clock

with no tri-stating of PCM_OUT. PSKEY_PCM_LOW_JITTER_CONFIG is described in Table 17.

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Name Bit position Description

-0 Set to 0

SLAVE MODE EN 1

0 selects Master mode with internal generation of PCM_CLK and

PCM_SYNC. 1 selects Slave mode requiring externally generated

PCM_CLK and PCM_SYNC. This should be set to 1 if

48M_PCM_CLK_GEN_EN (bit 11) is set.

SHORT SYNC EN 2

0 selects long frame sync (rising edge indicates start of frame), 1

selects short frame sync (falling edge indicates start of frame).

- 3 Set to 0

SIGN EXTENDED

EN 4

0 selects padding of 8 or 13-bit voice sample into a 16- bit slot by

inserting extra LSBs, 1 selects sign extension. When padding is

selected with 3-bit voice sample, the 3 padding bits are the audio gain

setting; with 8-bit samples the 8 padding bits are zeroes.

LSB FIRST EN 5 0 transmits and receives voice samples MSB first, 1 uses LSB first.

TX TRISTATE EN 6

0 drives PCM_OUT continuously, 1 tri-states PCM_OUT immediately

after the falling edge of PCM_CLK in the last bit of an active slot,

assuming the next slot is not active.

TX TRISTATE

RISING EDGE EN

0 tristates PCM_OUT immediately after the falling edge of PCM_CLK

in the last bit of an active slot, assuming the next slot is also not active.

1 tristates PCM_OUT after the rising edge of PCM_CLK.

SYNC SUPPRESS

0 enables PCM_SYNC output when master, 1 suppresses PCM_SYNC

whilst keeping PCM_CLK running. Some CODECS utilize this to enter

a low power state.

GCI MODE EN 9 1 enables GCI mode.

MUTE EN 10 1 forces PCM_OUT to 0.

48M PCM CLK GEN

0 sets PCM_CLK and PCM_SYNC generation via DDS from internal 4

MHz clock, as for BlueCore4-External. 1 sets PCM_CLK and

PCM_SYNC generation via DDS from internal 48 MHz clock.

LONG LENGTH

SYNC EN

0 sets PCM_SYNC length to 8 PCM_CLK cycles and 1 sets length to

16 PCM_CLK cycles. Only applies for long frame sync and with

48M_PCM_CLK_GEN_EN set to 1.

-[20:16] Set to 0b00000.

MASTER CLK RATE [22:21]

Selects 128 (0b01), 256 (0b00), 512 (0b10) kHz PCM_CLK frequency

when master and 48M_PCM_CLK_GEN_EN (bit 11) is low.

ACTIVE SLOT [26:23] Default is 0001. Ignored by firmaware

SAMPLE_FORMAT [28:27]

Selects between 13 (0b00), 16 (0b01), 8 (0b10) bit sample with 16

cycle slot duration 8 (0b11) bit sample 8 cycle slot duration.

Table 16: PSKEY_PCM_CONFIG32 description

Name Bit position Description

CNT LIMIT [12:0] Sets PCM_CLK counter limit

CNT RATE [23:16] Sets PCM_CLK count rate.

SYNC LIMIT [31:24] Sets PCM_SYNC division relative to PCM_CLK.

Table 17: PSKEY_PCM_LOW_JITTER_CONFIG Description

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Page 32 of 52

6 I/O Parallel Ports

The Parallel Input Output (PIO) Port is a general-purpose I/O interface to WT12. The port consists of six

programmable, bi-directional I/O lines, PIO[2:7]. Programmable I/O lines can be accessed either via an

embedded application running on WT12 or via private channel or manufacturer-specific HCI commands.

All PIO lines are configured as inputs with weak pull downs at reset.

PIO[2] / USB_PULL_UP (1)

The function depends on whether WT12 is a USB or UART capable version. On UART versions, this terminal

is a programmable I/O. On USB versions, it can drive a pull-up resistor on USB_D+. For application using

external RAM this terminal may be programmed for chip select.

PIO[3] / USB_WAKE_UP (1)

On UART versions of WT12 this terminal is a programmable I/O. On USB versions, its function is selected by

setting the Persistent Store Key PSKEY_USB_PIO_WAKEUP (0x2cf) either as a programmable I/O or as a

USB_WAKE_UP function.

PIO[4] / USB_ON (1)

On UART versions of WT12 this terminal is a programmable I/O. On USB versions, the USB_ON function is

also selectable.

PIO[5] / USB_DETACH (1)

On UART versions of WT12 this terminal is a programmable I/O. On USB versions, the USB_DETACH

function is also selectable.

PIO[6] / CLK_REQ

Function is determined by Persistent Store Keys. Using PSKEY_CLOCK_REQUEST_ENABLE, (0x246) this

terminal can be configured to be low when WT12 is in deep sleep and high when a clock is required. The

clock must be supplied within 4ms of the rising edge of PIO[6] to avoid losing timing accuracy in certain

Bluetooth operating modes.

PIO[7]

Programmable I/O terminal.

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Page 33 of 52

7 Software Stacks

WT12 is supplied with Bluetooth v2.1 + EDR compliant stack firmware, which runs on the internal RISC

microcontroller.

The WT12 software architecture allows Bluetooth processing and the application program to be shared in

different ways between the internal RISC microcontroller and an external host processor (if any). The upper

layers of the Bluetooth stack (above HCI) can be run either on-chip or on the host processor.

7.1 iWRAP Stack

PCM I/O

Host I/O

Radio

48kB RAM Baseband MCU

HCI

L2CAP

RFCOMM SDP

iWRAP

UART

Host I/O

PCM

Figure 22: WRAP THOR VM Stack

In figure 23 above, the iWRAP software solution is described. In this version of the stack firmware shown no

host processor is required to run the Bluetooth protocol stack. All software layers, including application

software, run on the internal RISC processor in a protected user software execution environment known as a

Virtual Machine (VM).

The host processor interfaces to iWRAP software via one or more of the physical interfaces, which are also

shown in the figure 23. The most common interfacing is done via UART interface using the ASCII commands

supported by the iWRAP software. With these ASCII commands the user can access Bluetooth functionality

without paying any attention to the complexity, which lies in the Bluetooth protocol stack.

The user may write applications code to run on the host processor to control iWRAP software with ASCII

commands and to develop Bluetooth powered applications.

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Page 34 of 52

7.2 HCI Stack

PCM I/O

Host I/O

Radio

48kB RAM Baseband MCU

HCI

UART

USB

Host

I/O

PCM

Figure 23: HCI Stack

In the implementation shown in figure 24 the internal processor runs the Bluetooth stack up to the Host

Controller Interface (HCI). The Host processor must provide all upper layers including the application.

7.2.1 Standard functionality

The firmware was written against the Bluetooth v2.1 + EDR specification and supports the following

functionality:

 Secure simple pairing

 Sniff subrating

 Encryption pause resume

 Packet boundary flags

 Extended inquiry response

 AFH as Master and Automatic Channel Classification

 Faster connection - enhanced inquiry scan (immediate FHS response)

 LMP improvements

 Parameter ranges

 Fast Connect - Interlaced Inquiry and Page Scan plus RSSI during Inquiry

 SCO handle

 Bluetooth components:

 Baseband (including LC)

 LM

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 HCI

 Standard UART and USB HCI Transport Layers

 All standard Bluetooth radio packet types

 Full Bluetooth data rate, enhanced data rates of 2 and 3Mbps. This is the maximum allowed by

 Operation with up to seven active ACL links

 Scatternet v2.5 operation

 eSCO

 Operation with up to three SCO or eSCO links routed to one or more remote devices (dependent on

the parameters requested by the host, for example, to have three HV3 SCO links, all the links must go

to slave devices)

 All standard SCO voice coding including transparent SCO

 Standard operating modes: Page, Inquiry, Page-Scan and Inquiry-Scan

 All standard pairing, authentication, link key and encryption operations

 Standard Bluetooth power saving mechanisms: Hold, Sniff and Park modes, including Forced Hold

 Dynamic control of peers' transmit power via LMP

 Master/Slave switch

 Broadcast

 Channel quality driven data rate

 All standard Bluetooth test modes

 EDR

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7.2.2 Extra functionality:

The release extends the standard Bluetooth functionality with the following features:

 Support for BCSP, a proprietary, reliable alternative to the standard Bluetooth UART Host Transport

(H4)

o A set of manufacturer-specific HCI extension commands, called BCCMDs, which provide:

o Access to the IC’s general-purpose PIO port

o Negotiated effective encryption key length on established Bluetooth links

o Access to the firmware’s random number generator

o Controls to set the default and maximum transmit powers; helping to reduce interference

between overlapping, fixed-location piconets

o UART configuration

o Radio transmitter enable/disable; using a simple command to connect to a dedicated hardware

switch that determines whether the radio can transmit

o Control of audio routing

 The firmware can read the voltage on several of the IC’s external pins. This is normally used to build a

battery monitor, using either VM or host code (BlueCore4-Audio Flash can also read the battery

voltage internally).

 The firmware provides support using VM to control the on-chip Battery Charger hardware for those Ics

that provide this functionality

 A block of BCCMDs provides access to the IC’s PS configuration database. The database holds the

device’s Bluetooth address, Class of Device, radio (transmit class) configuration, SCO routing, LM

and USB constants, etc.

 A UART break condition can be used in three ways:

o Presenting a UART break condition to the IC can force the IC to perform a hardware reboot

o Presenting a break condition at boot time can hold the IC in a low power state, preventing

normal initialisation while the condition exists

o With BCSP, the firmware can be configured to assert a break condition to the host before

sending data; normally used to wake the host from a Deep Sleep state

 The DFU v1.0 standard has been extended with public/private key authentication, allowing

manufacturers to control the firmware that can be loaded onto their Bluetooth modules

 A modified version of the DFU v1.0 protocol allows firmware upgrade via the IC’s UART

 A block of “radio test” or BIST commands allows direct control of the IC’s radio. This aids the

development of modules’ radio designs, and can be used to support Bluetooth qualification.

 The firmware provides the VM environment in which to run application-specific code. Although the VM

is mainly used with BlueLab, the VM can be used with this build, configured to act as an HCI device,

to perform simple tasks such as flashing LEDs via the IC’s PIO port.

 Hardware low power modes: Shallow Sleep and Deep Sleep. The IC drops into modes that

significantly reduce power consumption when the software goes idle.

 Support for eSCO connections at both HCI and RFCOMM levels

 SCO and eSCO channels are normally routed over HCI (over BCSP). However, up to three

SCO/eSCO channels can be routed over the IC’s single PCM port (at the same time as routing any

other SCO/eSCO channels over HCI). One SCO/eSCO link can be routed over the internal codec.

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7.3 VM Stack

PCM I/O

Host I/O

Radio

48kB RAM Baseband MCU

HCI

L2CAP

RFCOMM SDP

VM Application Software

UART

USB

Host

I/O

PCM

Figure 24: VM Stack

In figure above, this version of the stack firmware shown requires no host processor (but can use a host

processor for debugging etc.). All software layers, including application software, run on the internal RISC

processor in a protected user software execution environment known as a Virtual Machine (VM).

The user may write custom application code to run on the BlueCore VM using BlueLab™ software

development kit (SDK) supplied with the Casira development kit, available separately from Bluegiga or

directly form CSR. This code will then execute alongside the main WRAP THOR firmware. The user is able

to make calls to the WRAP THOR firmware for various operations. WRAP THOR firmware is not equal to

iWRAP firmware, which on the contrary does not allow user to run own firmware in the module.

The execution environment is structured so the user application does not adversely affect the main software

routines, thus ensuring that the Bluetooth stack software component does not need re-qualification when the

application is changed.

Using the VM and the BlueLab SDK the user is able to develop applications such as a cordless headset or

other profiles without the requirement of a host controller. BlueLab is supplied with example code including a

full implementation of the headset profile.

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Notes:

Sample applications to control PIO lines can also be written with BlueLab SDK and the VM for the HCI stack.

7.4 Software Development

WT12 Evaluation Kits are available to allow the evaluation of the WT12 hardware and software as well CSR

BlueLab toolkit for developing on-chip and host software.

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8 Enhanced Data Rate

EDR has been introduced to provide 2x and optionally 3x data rates with minimal disruption to higher layers of

the Bluetooth stack. CSR supports both of the new data rates, with WT12. WT12 is compliant with revision

v2.0.E.2 of the specification.

8.1 Enhanced Data Rate Baseband

At the baseband level EDR uses the same 1.6kHz slot rate as basic data rate and therefore the packets can

be 1, 3, or 5 slots long as per the basic data rate. Where EDR differs from the basic data rate is that in the

same 1MHz symbol rate 2 or 3bits are used per symbol, compared to 1bit per symbol used by the basic data

rate. To achieve the increase in number of bits symbol, two new modulation schemes have been introduced

as summarized in Table 18 presented below and the modulation schemes are explained in the further

sections.

Scheme Bits per symbol Modulation

Basic data rate 1 GFSK

Enhanced data rate 2 P/4 DQPSK

Enhanced data rate 3 8DPSK (optional)

Table 18: Data rate schemes

Although the EDR uses new packets Link establishment and management are unchanged and still use Basic

Rate packets.

8.2 Enhanced Data Rate

4-state Differential Phase Shift Keying

2 bits determine phase shift between consecutive symbols

/4 rotation avoids phase shift of

, which would cause large amplitude variation

Raised Cosine pulse shaping filter to further reduce side band emissions

Bit pattern Phase shift







11 

Table 19: 2 bits determine phase shift between consecutive symbols

8.3 8DQPSK

8-state Differential Phase-Shift Keying

Three bits determine phase shift between consecutive symbols.

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Bit pattern Phase shift

 

 

 

 

 

 

 

 

Table 20: 3 bits determine phase shift between consecutive symbols

Figure 25: 8DQPSK

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9 Layout and Soldering Considerations

9.1 Soldering recommendations

WT12 is compatible with industrial standard reflow profile for Pb-free solders. The reflow profile used is

dependent on the thermal mass of the entire populated PCB, heat transfer efficiency of the oven and

particular type of solder paste used. Consult the datasheet of particular solder paste for profile configurations.

Bluegiga Technologies will give following recommendations for soldering the module to ensure reliable solder

joint and operation of the module after soldering. Since the profile used is process and layout dependent, the

optimum profile should be studied case by case. Thus following recommendation should be taken as a

starting point guide.

 Refer to technical documentations of particular solder paste for profile configurations

 Avoid using more than one flow.

 Reliability of the solder joint and self-alignment of the component are dependent on the

solder volume. Minimum of 150m stencil thickness is recommended.

 Aperture size of the stencil should be 1:1 with the pad size.

 A low residue, “no clean” solder paste should be used due to low mounted height of the

component.

9.2 Layout guidelines

It is strongly recommended to use good layout practices to ensure proper operation of the module. Placing

copper or any metal near antenna deteriorates its operation by having effect on the matching properties. Metal

shield around the antenna will prevent the radiation and thus metal case should not be used with the module.

Use grounding vias separated max 3 mm apart at the edge of grounding areas to prevent RF penetrating

inside the PCB and causing an unintentional resonator. Use GND vias all around the PCB edges. Figure 5

illustrates recommended PCB design around the antenna of WT12 when the module is placed at the edge of

a PCB.

Do not place copper on the top layer under the module, as shown in figure 5. The module has vias on the area

shown, which can cause short circuit if there is copper underneath. Any metal placed closer than 20 mm in

any direction from the antenna changes the matching properties and thus will considerably deteriorate the RF

performance of the module.

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Figure 26: Suggested PCB design around ACX antenna with the module at the edge of PCB

Following recommendations helps to avoid EMC problems arising in the design. Note that each design is

unique and the following list do not consider all basic design rules such as avoiding capacitive coupling

between signal lines. Following list is aimed to avoid EMC problems caused by RF part of the module. Use

good consideration to avoid problems arising from digital signals in the design.

 Do not remove copper from the PCB more than needed. Use ground filling as much as

possible. However remove small floating islands after copper pour.

 Do not place a ground plane underneath the antenna. The grounding areas under the

module should be designed as shown in Figure 26.

 Use conductive vias separated max. 3 mm apart at the edge of the ground areas. This

prevents RF to penetrate inside the PCB. Use ground vias extensively all over the PCB. If

you allow RF freely inside the PCB, you have a potential resonator in your hand. All the

traces in (and on) the PCB are potential antennas.

 Avoid loops.

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 Ensure that signal lines have return paths as short as possible. For example if a signal

goes to an inner layer through a via, always use ground vias around it. Locate them

tightly and symmetrically around the signal vias.

 Routing of any sensitive signals should be done in the inner layers of the PCB.

 Sensitive traces should have a ground area above and under the line. If this is not

possible make sure that the return path is short by other means (for example using a

ground line next to the signal line).

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10 WT12 physical dimensions

20.0 mm

25.6 mm

0.6 mm

14.0 mm

10.0 mm

B l u e g i g a

5.0 mm

2.4 mm 2.0 mm

Tolerance for all the dimensions +/- 0.2 mm

Figure 27: WT12 dimensions

Figure 28: WT12 foot print

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Figure 29: WT12 recommended PCB land pattern

Figure 30: WT12 pad dimensions

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11 Package

bluegiga RoHS label

product

Label

1.0

Reel Configuration and Production Label

RoHS Compliant

T E C H N O L O G I E S

Figure 31: Reel information

0.1Max

37.5±0.2

Figure 32: Cover tape spec

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



P/N

3500275600

¡Ó0.1

2.5

¡Ó0.1

¡Ó0.1 ¡Ó0.3 +0.1 ¡Ó0.1 ¡Ó0.1

¡Ó0.1 ¡Ó0.1

25.9

14.4 20.2

BA W F

2.0

4.0

1.75 20.0

EP0 P1 P2

+0.1

-0.0

VACANT

?1.5

20 PCS

start

Package direction:

VACANT

quantity/500pcs

Detail B-B

20PCS

WT12

End of tape

Figure 33: Tape information

Dimensions

Tolerance

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12 Certifications

WT12 is compliant to the following specifications.

12.1 Bluetooth

WT12 module is qualified as a Bluetooth controller subsystem and it fullfills all the mandatory requirements of

Bluetooth 2.1 + EDR core spesification. If not modified in any way, it is a complete Bluetooth entity, containing

software and hardware functionality as well as the whole RF-part including the antenna. This practically

translates to that if the module is used without modification of any kind, it does not need any Bluetooth

approval work for evaluation on what needs to be tested.

WT12 qualified listing details:

https://www.Bluetooth.org/tpg/QLI_viewQDL.cfm?qid=17400

WT12 PICS details:

https://www.Bluetooth.org/tpg/showCorePICS.cfm?3A000A5A005C5043555E54

WT12 Qualified Design ID (QDID):

https://www.Bluetooth.org/tpg/QLI_viewQDL.cfm?qid=17400

12.2 FCC and IC

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions:

(1) this device may not cause harmful interference, and

(2) this device must accept any interference received, including interference that may cause undesired

operation.

FCC RF Radiation Exposure Statement:

This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment. End

users must follow the specific operating instructions for satisfying RF exposure compliance. This transmitter

must not be co-located or operating in conjunction with any other antenna or transmitter

IC Statements:

This device complies with Industry Canada licence-exempt RSS standard(s). Operation is subject to the

following two conditions: (1) this device may not cause interference, and (2) this device must accept any

interference, including interference that may cause undesired operation of the device.

Under Industry Canada regulations, this radio transmitter may only operate using an antenna of a type and

maximum (or lesser) gain approved for the transmitter by Industry Canada. To reduce potential radio

interference to other users, the antenna type and its gain should be so chosen that the equivalent isotropically

radiated power (e.i.r.p.) is not more than that necessary for successful communication.

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If detachable antennas are used:

This radio transmitter (identify the device by certification number, or model number ifCategory II) has been

approved by Industry Canada to operate with the integral chip antenna. Use of any other antenna is strictly

prohibited for use with this device.

OEM Responsibilities to comply with FCC and Industry Canada Regulations

The WT12 Module has been certified for integration into products only by OEM integrators under the following

condition:

 The transmitter module must not be co-located or operating in conjunction with any other antenna or

transmitter.

As long as the condition above is met, further transmitter testing will not be required. However, the OEM

integrator is still responsible for testing their end-product for any additional compliance requirements required

with this module installed (for example, digital device emissions, PC peripheral requirements, etc.).

IMPORTANT NOTE: In the event that the condition can not be met (for certain configurations or co-location

with another transmitter), then the FCC and Industry Canada authorizations are no longer considered valid

and the FCC ID and IC Certification Number can not be used on the final product. In these circumstances, the

OEM integrator will be responsible for re-evaluating the end product (including the transmitter) and obtaining a

separate FCC and Industry Canada authorization.

End Product Labeling

The WT12 module is labeled with its own FCC ID and IC Certification Number. If the FCC ID and IC

Certification Number are not visible when the module is installed inside another device, then the outside of the

device into which the module is installed must also display a label referring to the enclosed module. In that

case, the final end product must be labeled in a visible area with the following:

“Contains Transmitter Module FCC ID: QOQWT12A”

“Contains Transmitter Module IC: 5123A-BGTWT12A”

“Contains FCC ID: QOQWT12A

“Contains IC: 5123A-BGTWT12A”

The OEM integrator has to be aware not to provide information to the end user regarding how to install or

remove this RF module or change RF related parameters in the user manual of the end product.

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12.3 CE

WT12 is conformity with the following standards and/or normative documents:

EMC (Art. 3(1)(a)):

 EN 301 489-17:V2.1.1

o ESD immunity, EN 61000-4-2:2009

o Radiated electric field immunity, EN 61000-4-3:2006 +A1:2008

SPECTRUM (Art. 3(2)):

 EN 300 328 V1.7.1

o Equivalent isotropic radiated power, Clause No 4.3.1

o Frequency range, Clause No 4.3.3

o Frequency hopping, Clause No 4.3.4

o Medium access protocol, Clause No 4.3.5

o Transmitter spurious emissions, Clause No 4.3.6

o Receiver spurious emissions, Clause No 4.3.7

12.4 Japan

WT12 has type approval in Japan with identification code R 209- J00036

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13 RoHS Statement with a List of Banned Materials

WT12 meets the requirements of Directive 2002/95/EC of the European Parliament and of the Council on the

Restriction of Hazardous Substance (RoHS)

The following banned substances are not present in WT11, which is compliant with RoHS:

 Cadmium

 Lead

 Mercury

 Hexavalent chromium

 PBB (Polybrominated Bi-Phenyl)

 PBDE (Polybrominated Diphenyl Ether)

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14 Contact Information

Sales: sales@bluegiga.com

Technical support: http://techforum.bluegiga.com

Orders: orders@bluegiga.com

WWW: www.bluegiga.com

www.bluegiga.hk

Head Office / Finland:

Phone: +358-9-4355 060

Fax: +358-9-4355 0660

Sinikalliontie 5A

02630 ESPOO

FINLAND

Postal address / Finland:

P.O. BOX 120

02631 ESPOO

FINLAND

Sales Office / USA:

Phone: +1 770 291 2181

Fax: +1 770 291 2183

Bluegiga Technologies, Inc.

3235 Satellite Boulevard, Building 400, Suite 300

Duluth, GA, 30096, USA

Sales Office / Hong-Kong:

Phone: +852 3182 7321

Fax: +852 3972 5777

Bluegiga Technologies, Inc.

19/F Silver Fortune Plaza, 1 Wellington Street,

Central Hong Kong

Mouser Electronics

Authorized Distributor

Click to View Pricing, Inventory, Delivery & Lifecycle Information:

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