Linear Technology DC2376A User manual

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dc2376af
DEMO MANUAL DC2376A
Description
4-Channel 16-Bit/12-Bit
±10V VOUT SoftSpan DACs with
10ppm/°C Max Reference
Demonstration circuit 2376A features the LT C
®
2664,
4-channel 16-Bit/12-Bit ±10V VOUT SoftSpan™ DACs with
10ppm/°C max reference in a 5mm ×5mm QFN package.
This device features per-channel SoftSpan configuration
with five output ranges: 0V to 5V, 0V to 10V, ±2.5V, ±5V,
and ±10V. A toggle feature allows any or all DACs to switch
betweentwoprogrammedcodesviaasingleSPIcommand
or by the TGP input pin. The versatile SPI interface can
operate on any logic level between 1.71V and 5.5V, for
easy interface to lower voltage microcontrollers or FPGAs.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
SoftSpan and QuikEval are trademarks of Linear Technology Corporation. All other trademarks
are the property of their respective owners.
DC2376A-A is populated with the 16-bit version of the
LTC2664. DC2376A-B is populated with the 12-bit version
for lower resolution applications.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2376A
Figure 1. Connection Diagram
SIGNAL
GROUND
MEASURE REF VOLTAGE,
MUX OUTPUT
SIGNAL
GROUND
DAC OUTPUTS,
MUX INPUTS
+
–
+
–
OVERTEMPERATURE
OUTPUT
SEE TEXT. LDAC, TGP, CLR
PULLED TO IOVCC W/5kΩ
ANALOG SUPPLIES
(±15V ALLOWS ALL
SOFTSPAN RANGES)

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DEMO MANUAL DC2376A
Quick start proceDure
Download and install QuikEval™ from:
http://www.linear.com/designtools/software/#Data
Connect a DC590 controller or DC2026 Linduino with
DC590emulatorfirmwaretotheDC2376Awiththesupplied
ribbon cable. Connect low-noise analog power supplies
as shown in Figure 1. A±15V supply will allow all of the
SoftSpan ranges to be used, refer to the LTC2664 data
sheet for other supply options if not all SoftSpan ranges
are used.
Connect the controller to the host PC’s USB port and run
QuikEval. The DC2376A software will be downloaded and
installed, after which a jumper setting window will appear
as shown in Figure 2. The default settings are internal
reference, SoftSpan operation with 0V to 5V range, 0V
output on power-up. If the jumpers on the board have been
changed to a different configuration, select the appropri-
ate options in the pull-down menus to match the board.
Click OK and the main dialog will appear. The control panel
gives access to all of the LTC2664’s functionality includ-
ing per-channel SoftSpan ranges, toggling, Power-Down,
etc. Detailed instructions are provided in the Help menu.
Figure 2. Jumper Settings Dialog

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DEMO MANUAL DC2376A
Figure 3. Main Control Panel
Quick start proceDure

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DEMO MANUAL DC2376A
Quick start proceDure
External Connections
J1: Interface connector to DC590 controller or Linduino.
Provides OVP power, SPI interface, and board identifica-
tion.
V–, GND, V+:Analog supplies, connected to the LTC2664
V+and V–pins. Nominally ±15V for operation in all Soft-
Span ranges. Refer to the data sheet for other supply
configurations.
GND: Four additional ground posts and exposed ground
plane around board edge allow solid connection to pro-
totype circuitry and measurement equipment.
VCC: Analog supply voltage. Normally supplied by an
onboard LT1761-5 fixed 5V regulator that is powered
from the V+supply. For single 5V supply applications, VCC
may be tied directly to V+and supplied with 4.5V to 5.5V.
IOVCC: Digital interface power. No connection to this pin is
required when used with a DC590 or Linduino controller.
If another controller is used, connect to digital supply that
powers the SPI bus controller (1.71 to 5.5V).
REF: Connection to the REF pin. In internal reference
mode, the reference voltage may be monitored at this
point. Placing REF_SEL jumper in the EXT position allows
an external reference to be connected to this point.
MUX: Monitor Mux output. Allows surveying the DAC
outputs, as well as the auxiliary MUX inputs, V+, V–REF,
REFLO,andan internal temperature sensor, under software
control. Must be measured with a high impedance meter
(output impedance is nominally 2.1kΩ).
VOUT0 to VOUT3: DAC outputs.
MUXIN0 to MUXIN3: Analog Multiplexer Auxiliary Inputs.
CLR:Asynchronous clear input (pulled high to OVP with
a4.99k resistor). Pull to ground to reset the DAC to the
power-on reset value (determined by MSPx pins.)
TGP: Toggle input (pulled high to OVP with a 4.99k resis-
tor). A high level on this pin enables software toggling. See
data sheet for a complete description of toggle operation.
LDAC:Asynchronous DAC update. If CS/LD is high at the
falling edge of LDAC, DAC outputs will be updated with
the contents of the input registers. If CS/LD is low when
LDAC goes low, the DAC registers are updated after CS/
LD returns high.
OVRTMP:Overtemperature pin (pulled high to IOVCC with
a4.99k resistor). The LTC2664 pulls this pin low if the die
temperature exceeds approximately 160°C. It is released
on the next rising edge of CS/LD.

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DEMO MANUAL DC2376A
Quick start proceDure
Table 1
MSP2 MSP1 MSP0 OUTPUT RANGE RESET CODE MANUAL SPAN SoftSpan
0 0 0 ±10V Mid-Scale X
0 0 1 ±5V Mid-Scale X
0 1 0 ±2.5V Mid-Scale X
0 1 1 0V to 10V Zero-Scale X
1 0 0 0V to 10V Mid-Scale X
1 0 1 0V to 5V Zero-Scale X
1 1 0 0V to 5V Mid-Scale X
1 1 1 0V to 5V Zero-Scale X
Jumpers
REF_SEL (JP1): Selects internal or external reference
mode. (See data sheet description of REFCOMP pin.)
MSP0, MSP1, MSP2 (JP2, JP3, JP4): Manual Span
control. Setting all jumpers to the 1 position (Default)
selects SoftSpan operation, with a power-up default span
of 0V to 5V, and reset to Zero-Scale. Other options are
listed in Table 1.
LEDs
OVRTMP:Lights when OVRTMP pin asserts, indicating an
overtemperature state. (Note that LED will light if positive
analog supply is present and OVP is not. OVP is normally
supplied by the controller.)
Test Points
The SPI bus is available on a row of through-hole test
points next to J1 that may be used to monitor the bus or
to drive the bus with an external controller.
EEGND, WP: For factory use only.

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DEMO MANUAL DC2376A
parts List
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 3 C1, C6, C7 CAP, X5R, 10µF 25V, 10%, 1206 MURATA, GRM31CR61E106KA12L
2 9 C2, C3, C8, C9, C11 TO C15 CAP, X7R, 0.1µF 25V, 10%, 0603 MURATA, GRM188R71E104KA01D
3 1 C5 CAP, X7R, 0.01µF 25V, 10%, 0603 MURATA, GRM188R71E103KA01D
4 2 D1, D2 DIODE, SCHOTTKY DUAL 30V, SOT23-3 DIODES INC, BAT54C-7-F
5 23 E1 TO E17, E22, E24, E28 TO E31 TURRET, TESTPOINT 0.064" MILL-MAX, 2308-2-00-80-00-00-07-0
6 4 JP1, JP2, JP3, JP4 HEADER, 2MM SINGLE STR 3POS SULLINS, NRPN031PAEN-RC
7 1 J1 CONN, HEADER 14POS 2MM VERT GOLD MOLEX, 87831-1420
8 1 LED1 LED, RED, LED-ROHM-SML-010VT ROHM, SML-010VTT86L
9 1 Q1 MOSFET, N-CH 60V 300MA SOT-23 VISHAY SILICONIX, 2N7002K-T1-E3
10 0 R1, R2, R10 RES, 0603 OPT
11 8 R3 TO R9, R12 RES, CHIP, 4.99k, 1/10W, 1% 0603 VISHAY, CRCW06034K99FKEA
12 1 R11 RES, CHIP, 1k, 1/10W, 1% 0603 VISHAY, CRCW06031K00FKEA
13 1 U2 IC, LT1761ES5-5, SOT23-5 LINEAR TECHNOLOGY, LT1761ES5-5#PBF
14 1 U3 IC, 24LC025-I/ST, TSSOP8 MICROCHIP, 24LC025-I/ST
DC2376A-A Required Circuit Components
2 1 U1 IC, 16-BIT, QFN32UH-5X5 LINEAR TECHNOLOGY, LTC2664IUH-16
DC2376A-B Required Circuit Components
2 1 U1 IC, 12-BIT, QFN32UH-5X5 LINEAR TECHNOLOGY, LTC2664IUH-12

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DEMO MANUAL DC2376A
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
NOTE: UNLESS OTHERWISE SPECIFIED 1. ALL CAPACITORS ARE IN MICROFARADS, 0603.
B
ASSY
A
U1
LTC2664-16
-Bit 16 12LTC2664-12
*SUFFIX
16 12
V+
V-
+5V
V-
V+
+5V
+5V
+5V
OVP
OVP
OVP
OVP
OVP
+5V +5V
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
MARK T.PRODUCTION1 08-04-15
__
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
MARK T.PRODUCTION1 08-04-15
__
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
MARK T.PRODUCTION1 08-04-15
__
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] 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
1
Tuesday, August 04, 2015
11
QUAD 16/12-BIT +/-10V VOUT SOFT SPAN DACS
KIM T.
MARK T.
N/A
LTC2664IUH FAMILY DEMO CIRCUIT 2376A
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] 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
1
Tuesday, August 04, 2015
11
QUAD 16/12-BIT +/-10V VOUT SOFT SPAN DACS
KIM T.
MARK T.
N/A
LTC2664IUH FAMILY DEMO CIRCUIT 2376A
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] 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
1
Tuesday, August 04, 2015
11
QUAD 16/12-BIT +/-10V VOUT SOFT SPAN DACS
KIM T.
MARK T.
N/A
LTC2664IUH FAMILY DEMO CIRCUIT 2376A
JP4
MSP2
1 0
1 3 2
SCK
R6
4.99k
E17
GND
E13
GND JP2
MSP0
1 0
1 3 2
R4
4.99k
E11 MUXIN2
C11 0.1uF
GND
E10
IOVCC
E9 MUXIN1
SDI
R8
4.99k
E22
CLR
C7 10uF 25V 1206
C6 10uF 25V 1206
R9
4.99k
WP
C14 0.1uF
C15 0.1uF
EEPROM
ARRAY
U3
24LC025-I /ST
SDA 5
VCC 8
A0 1 A1 2 A2 3
GND
4
WP 7
SCL 6
E15 VOUT3
C1 10uF 25V 1206
E3
V-
R11 1k
C9
0.1uF
R10 OPT
E5 REF
SDO
E28 MUX
GND
E12 VOUT2
LED1 RED
2 1
R2 OPT
E14
TGL
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
JP3
MSP1
1 0
1 3 2
E4 GND
R7
4.99k
C3
0.1uF
E31
VCC
R3
4.99k
R1 OPT
E2
GND
C12 0.1uF
R5
4.99k
R12
4.99k
D1
BAT54C
1 3
2
D2
BAT54C
1 3
2
Q1
2N7002
2
1
3
C13 0.1uF
E6 MUXIN0
E16 MUXIN3
C5
0.01uF
EEGND
CS/LD
E24
LDAC
U2 LT1761ES5-5
BYP 4
OUT 5
VIN
1
GND
2
SHDN
3
E29 OVRTMP
E1
V+
E8 VOUT1
C8
0.1uF
E7 VOUT0
JP1
REF SEL
INT
EXT
1 3 2
U1
LTC2664 *
VOUT3 22
MUXIN3 23
V+ 7
MUXIN2 20
VOUT2 21
EP
33
TGP
17
V-
8
MUXOUT 9
REFLO
27
GND
11
REFCOMP 26
REFLO
10
GND
29
VCC 28
LDAC
12
MSP2
1
MSP0
31
MSP1
32
IOVCC 18
VOUT0 3
OVRTMP 30
REF 25
VOUT1 4
MUXIN0 2
CLR
24
SDI
16
CS/LD
13
SCK
14
SDO
15
MUXIN1 5
E30 GND
C2
0.1uF

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dc2376af
DEMO MANUAL DC2376A
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2015
LT 0915 • PRINTED IN USA
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LT C ) 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 LT C 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 LT C 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. LT C assumes no liability for applications assistance,
customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.
LT C 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 LT C applica-
tion engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation