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dc1703af
DEMO MANUAL DC1703A
Description
LTC2655: Quad I2C
16-/12-Bit Rail-to-Rail DACs with
10ppm/°C Max Reference
Demonstration circuit 1703A features the LTC
®
2655 quad
16-/12-bit DAC. The LTC2655 is a family of 16-/12- bit
rail-to-rail DACs with integrated 10ppm/°C maximum
reference. The LTC2655 advances performance standards
for output drive, crosstalk and load regulation in single
supply, voltage-output multiple DACs.
Design files for this circuit board are available at
http://www.linear.com/demo
L, LT, LTC, LTM, µModule, Linear Technology and the Linear logo are registered trademarks
and QuikEval is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
Figure 1. Connection Diagram
Analog Outputs
To DC590
Table 1. LTC2655 Demo Board Variations
DEMO BOARD TYPE LTC2655 VARIATION FULL-SCALE VOLTAGE
DC1703A-A LTC2655CUF-L16 2.5V
DC1703A-B LTC2655CUF-H16 4.096V
DC1703A-C LTC2655CUF-L12 2.5V
DC1703A-D LTC2655CUF-H12 4.096V
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dc1703af
DEMO MANUAL DC1703A
quick start proceDure
Figure 2. Demo Board Setup
Connect the DC1703A to a DC590 USB serial controller
using the supplied 14 conductor ribbon cable. Connect
the DC590 to a host PC with a standard USB A/B cable.
Run the QuikEval™ evaluation software supplied with the
DC590 or download it from www.linear.com. The correct
control panel will be loaded automatically. In order to
update the DAC output value, fill in desired output code
inside the corresponding DAC box.
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dc1703af
DEMO MANUAL DC1703A
HarDware set-up
Jumpers
REF: VREF Select. This jumper selects which mode the
LTC2655 powers up in: external reference (EXT) or internal
reference (INT).
PORSEL: Power-Up Mode. The LTC2655 can be set to
either power-up in mid-scale or zero-scale.
CA2, CA1, CA0: Address Selection Jumpers. These jumpers
are used to select the I2C address of the DAC. Any changes
here should also be made in the QuikEval software.
Analog Connections
DAC Outputs: The 4 DAC outputs from the LTC2655 are
brought out to turrets labeled VOUTA through VOUTD. These
may be connected to external instruments or other circuitry.
NOTE: DAC outputs are not in alphabetical order on the
circuit board.
VREF : The VREF turret is connected directly to the reference
terminals of the LTC2655. The on-chip reference may be
turned off, allowing the DAC reference pin to be driven
from this turret. Alternatively, when the on-chip reference
is on and active, the voltage can be monitored at this turret.
V+: Unregulated 10V is present here when a DC590 is
connected. This turret is provided for monitoring purposes
only and should not be connected to any other turrets on
the board.
Grounding and Power Connections
Power (VCC): Normally the DC1703A is powered by the
DC590 controller. VCC can be supplied to this turret,
however the power supply on DC590 must be disabled.
Refer to DC590 Quick Start Guide for more details on this
mode of operation.
Grounding: There are 3 ground turrets provided (labeled
GND), as well as ground strips on the top and the bottom
of the board.
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dc1703af
DEMO MANUAL DC1703A
parts List
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER, PART NUMBER
1 3 C1, C2, C3 Capacitor, X7R, 0.1µF 16V, 0402 TDK, C1005X7R1C104K
2 1 C4 Capacitor, X7R, 0.047µF 16V, 0402 TDK, C1005X7R1C473K
3 10 E1-E10 TP, Turret, 0.064" Mill-Max, 2308-2-00-80-00-00-07-0
4 5 JP1-JP5 Jumper, 3-Pin 1 Row 0.079CC Samtec, TMM-103-02-L-S
5 1 J1 Header, 2×7 Pin, 0.079CC Molex, 87831-1420
6 4 R1, R2, R3, R4 Resistor., Chip 4.99K 1/16W 1%,0402 NIC, NRC04F4991TRF
7 1 U2 IC, Serial EEPROM, TSSOP8 Microchip, 24LC025-I /ST
8 5 Shunts as Shown on
Assembly Drawing
Shunt, 0.079" Center Samtec, 2SN-BK-G
9 1 Stencil Top Side Only Stencil, 1703A
U1-A IC, LTC2655CUF-L16, 4mm × 4mm QFN20UF Linear Technology, LTC2655CUF-L16
U1-B IC, LTC2655CUF-H16, 4mm × 4mm QFN20UF Linear Technology, LTC2655CUF-H16
U1-C IC, LTC2655CUF-L12, 4mm × 4mm QFN20UF Linear Technology, LTC2655CUF-L12
U1-D IC, LTC2655CUF-H12, 4mm × 4mm QFN20UF Linear Technology, LTC2655CUF-H12
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dc1703af
DEMO MANUAL DC1703A
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
scHematic Diagram
5
5
4
4
3
3
2
2
1
1
D D
C C
B B
A A
ALL CAPACITORS ARE IN MICROFARADS, 0402.
NOTES: UNLESS OTHERWISE SPECIFIED
2. INSTALL SHUNTS AS SHOWN.
1. ALL RESISTORS ARE IN OHMS, 0402.
O
ASSY U1
-A
-B
LTC2655CUF-L16
LTC2655CUF-H16
*
-C
-D LTC2655CUF-H12
LTC2655CUF-L12
-BIT
16
16
12
12
VCCV+
VCC
VCC
VCC
VCCVCCVCC
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY
Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
2
LTC2655CUF FAMILY
Thursday, November 11, 2010 1 1
QUAD 12/16-BIT RAIL-TO-RAIL I2C DAC
KT
LEO C.
N/A
DEMO CIRCUIT 1703A
WITH 10ppm/ C MAX REFERENCE
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY
Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
2
LTC2655CUF FAMILY
Thursday, November 11, 2010 1 1
QUAD 12/16-BIT RAIL-TO-RAIL I2C DAC
KT
LEO C.
N/A
DEMO CIRCUIT 1703A
WITH 10ppm/ C MAX REFERENCE
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY
Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
2
LTC2655CUF FAMILY
Thursday, November 11, 2010 1 1
QUAD 12/16-BIT RAIL-TO-RAIL I2C DAC
KT
LEO C.
N/A
DEMO CIRCUIT 1703A
WITH 10ppm/ C MAX REFERENCE
REVISION HISTORY
DESCRIPTION DATEAPPROVEDECO REV
LEO C.
2ND PROTOTYPE
211-11-10
_
REVISION HISTORY
DESCRIPTION DATEAPPROVEDECO REV
LEO C.
2ND PROTOTYPE
211-11-10
_
REVISION HISTORY
DESCRIPTION DATEAPPROVEDECO REV
LEO C.
2ND PROTOTYPE
211-11-10
_
JP3
GND
VCC
CA0
JP3
GND
VCC
CA0
1
3
2
JP4
GND
VCC
CA1
JP4
GND
VCC
CA1
1
3
2
C3
0.1uF
C3
0.1uF
E8 VOUTC
E8 VOUTC
E4 GND
E4 GND
E7 VOUTB
E7 VOUTB
J1
HD2X7-079-MOLEX
J1
HD2X7-079-MOLEX
MOSI/SDA 7
EESDA 9
V+ 1
5V 2
CS 6
SCK/SCL 4
EEVCC 10
MISO 5
EESCL 11
EEGND 12
AUX 14
GND
3
GND
13
GND
8
JP5
GND
VCC
CA2
JP5
GND
VCC
CA2
1
3
2
U1
*
U1
*
CA2
6
SCL
7
DNC
8
REFCOMP 2
VOUTB 3
REFIN/OUT 4
LDAC 5
VOUTA 1
SDA
9
CA1
10 CA0
11
PORSEL
12
VOUTC 13
VOUTD 14
REFLO
20
GND
19
VCC 18
DNC 17
DNC 16
DNC
15
GND
21
E6 VOUTA
E6 VOUTA
C4
0.047uF
C4
0.047uF
E5 GND
E5 GND
E2
VCC
E2
VCC
SDASDA
R3
4.99K
R3
4.99K
R1
4.99K
R1
4.99K
R4
4.99K
R4
4.99K
JP1
EXT
INT
REF
JP1
EXT
INT
REF 1
3
2
U2
24LC025-I /ST
U2
24LC025-I /ST
SDA 5
VCC 8
A0
1
A1
2
A2
3
VSS
4
WP 7
SCL 6
LDACLDAC
C2
0.1uF
C2
0.1uF
E9 VOUTD
E9 VOUTD
E1
VREF
E1
VREF
JP2
ZS
MS
PORSEL
JP2
ZS
MS
PORSEL
1
3
2
SCLSCL
C1
0.1uF
C1
0.1uF
R2
4.99K
R2
4.99K
E3
GND
E3
GND
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dc1703af
DEMO MANUAL DC1703A
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com
LINEAR TECHNOLOGY CORPORATION 2011
LT 0511 • PRINTED IN USA
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions:
This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT
OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete
in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety
measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union
directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations.
If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date
of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU
OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS
FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR
ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.
The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LTC from all claims
arising from the handling or use of the goods. Due to the open construction of the product, it is the user’s responsibility to take any and all
appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or
agency certified (FCC, UL, CE, etc.).
No License is granted under any patent right or other intellectual property whatsoever. LTC assumes no liability for applications assistance,
customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.
LTC currently services a variety of customers for products around the world, and therefore this transaction is not exclusive.
Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and
observe good laboratory practice standards. Common sense is encouraged.
This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC applica-
tion engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation