DC934A - Demo Manual

DEMO MANUAL DC934A
LTC2607
16-Bit Dual Rail-to-Rail DAC
with I2C Interface
Description
Demonstration circuit 934A features the LTC®2607 dual
16-bit DAC. This device establishes a new board-density
benchmark for 16-bit DACs and advances performance
standards for output drive, load regulation, and crosstalk
in single supply, voltage-output DACs.
DC934A has many features for evaluating the performance
of the LTC2607. Onboard 5V, 4.096V, and 2.5V precision
references are provided, and the LTC2607 may be powered
by the 5V reference for evaluating rail-to-rail operation.
Another feature of this board is the onboard LTC2422
20‑bit ADC for monitoring DAC output voltage. The 16ppm
total error of this device is adequate for taking meaningful
measurements of various LTC2607 parameters.
Design files for this circuit board are available at
http://www.linear.com/demo
L, LT, LTC, LTM, 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. Proper Measurement Equipment Setup
Performance Summary
PARAMETER
Specifications are at TA = 25°C
CONDITION
Resolution
VALUE
16 Bits
Monotonicity
VCC = 5V, VREF = 4.096V
16 Bits
Differential Nonlinearity
VCC = 5V, VREF = 4.096V
±1LSB
Integral Nonlinearity
VCC = 5V, VREF = 4.096V
±19LSB Typical
Load Regulation
VCC = VREF = 5V, Mid-scale
IOUT = ±15 mA
2LSB/mA Max
DC Crosstalk
Due to Load Current Change on Any Other Channel
3µV/mA
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DEMO MANUAL DC934A
Quick Start Procedure
Connect DC934A to a DC590 USB serial controller using
the supplied 14-conductor ribbon cable. Connect DC590
to a host PC with a standard USB A/B cable. Run the
evaluation software supplied with DC590 or download it
from www.linear.com/software. The correct control panel
will be loaded automatically. Click the COLLECT button to
begin outputting codes to the DAC and reading back the
resulting output voltage.
Complete software documentation is available from the
Help menu item, as features may be added periodically.
Figure 2. Software Screenshot
Hardware Setup
Jumpers
JP1: VREF Select. Select 5V, 4.096V, or 2.5V reference.
To apply an external reference through the VREF turret,
remove this jumper.
JP2: VCC Select. VCC is taken either from the onboard 5V
reference or the 5V regulated supply from the controller
board. Selecting the 5V reference for VCC and VREF allows
characterization of rail to rail operation of the LTC2607.
JP3: ADC Disable. Set to ON for operation with DC590 serial controller. When using in customer’s end application,
the ADC can be completely disabled by setting jumper to
DISABLE.
For very sensitive noise measurements when using LTC
supplied software, set the output voltage and stop reading
voltage via the collect button on the control panel.
JP5: REFLO connection – either grounded or externally
supplied. Refer to the LTC2607 data sheet for REFLO details.
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DEMO MANUAL DC934A
Hardware Setup
JP4,6,7: I2C Address Selection. These are connected to the
CA0, CA1, CA2 pins. The demo software uses the global
I2C address, so these pins have no effect when used with
the QuikEval™ software. They can be used in prototyping
to set the I2C address of the LTC2607 – refer to the data
sheet for the mapping of CA0,1,2 levels to I2C addresses.
Analog Connections
VOUTA, VOUTB: LTC2607 Outputs
VREF: The VREF turret is connected directly to the reference
terminals of the LTC2607 and LTC2422 ADC. When one of
the onboard references is being used, the reference voltage
may be monitored at this point. An external reference may
also be applied to this turret after removing JP1.
Grounding and Power Connections
Power (VCC): Normally DC934A 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: Separate power and signal grounds are provided. Any large currents drawn from the DAC outputs
should be returned to power ground. Also, if an external
power supply is connected, power ground should be
used. Signal ground is connected to the exposed ground
planes at the top and bottom edges of the board, and to
the two turrets labeled GND. Use signal ground as the
reference point for measurements and connections to
external circuits.
Experiments
The following experiments are intended to demonstrate
some of the outstanding features of the LTC2607. All can
be performed using the onboard LTC2422 to monitor
the DAC output voltage. The indicated output voltage will
typically agree with an HP3458A voltmeter to 5 digits. If
a DAC will be sinking or sourcing a significant current,
then the output voltage should be measured as close to
the DAC as possible.
62.5μV for VREF = 4.096V) change in the LTC2607 output.
Set the DAC output to a voltage close to mid-scale. Select
the FINE slider on the control panel with the mouse and
use the right and left arrow keys to step the output by
single LSBs. The change should be clearly visible in the
output graph. (It may be necessary to wait for the graph
to clear if a large step has just occurred.)
Most of the data sheet specifications use a 4.096V reference, so this is the preferred reference to use for these
experiments. Using the 5V regulator as the source for VCC
has the limitation that VCC may be slightly lower than VREF,
which may affect the full-scale error. Selecting the 5V reference as the source for VCC overcomes this, however the
total current that the LTC2607 can source will be limited
to approximately 5mA.
Integral Nonlinearity
Using an external power supply is highly recommended for
these experiments, especially those that draw significant
current. Refer to the DC590 quick start guide for details.
Resolution
The onboard LTC2422 ADC has an input resolution of
6μV. This will easily resolve a 1LSB (76μV for VREF = 5V,
A rough measurement of INL can be taken using the onboard
ADC. Measure one of the LTC2607 outputs at code 256
and 65,535 and calculate the slope and intercept using a
spreadsheet. Next, take several readings at intermediate
points. The readings should not deviate from the calculated line by more than 64LSBs, and they will typically be
within 12LSBs.
Load Regulation/DC Output Impedance
Select 5V REG for VCC source. Set one of the outputs to
mid-scale (code 32768). Source or sink 15mA from one
of the DAC outputs by pulling it to power ground or VCC
with an appropriate value resistor. The voltage change
dc934af
3
DEMO MANUAL DC934A
Experiments
should be less than 2.25mV, corresponding to an output
impedance of 0.15Ω. Output impedance is typically less
than 0.030Ω. (measure DAC voltage at the output pin if
using a voltmeter.)
Gain Error
Zero Scale Error
DC Crosstalk
Set one of the DACs to code 0. The measured output should
be less than 9mV and will typically be less than 1mV.
Offset Error
Set one of the DACs to code 256. The output voltage should
be within 9mV of the correct value, or VREF • 256/65535.
Set one of the DACs to code 65,535. The output voltage
should be within 0.7% of VREF, and will typically be within
0.2%.
Set one of the DACs to mid-scale. Connect a 250Ω resistor
from the output to VCC or power ground (to sink or source
10mA, respectively, when the 5V reference is being used.)
The other output should not change by more than 3.5μV
per milliamp of load current.
Parts List
ITEM
QTY REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
Required Circuit Components
1
6
C1, C2, C4, C5, C6, C11
CAP., X5R, 1µF 10V, 0402
TDK, C1005X5R1A105MT
2
4
C3, C7, C8, C12
CAP., X7R, 0.1µF 16V, 0402
TDK, C1005X7R1C104MT
3
2
C9, C10
CAP., NPO, 100pF 50V, 0402
AVX, 04025A101JAT
4
9
E1-E9
TESTPOINT, TURRET, 0.064"
MILL-MAX, 2308-2
5
1
JP1
JMP, 2X3, 0.079CC
SAMTEC, TMM-103-02-L-D
6
6
JP2-JP7
JMP, 3 PIN 1 ROW 0.079CC
SAMTEC, TMM-103-02-L-S
7
7
SHUNTS FOR JP1-JP7 PIN 1 AND 2
SHUNT, 0.079" CENTER
SAMTEC, 2SN-BK-G
8
1
J1
HEADER, 2X7 PIN, 0.079CC
MOLEX, 87331-1420
9
3
R1, R2, R3
RES., CHIP 4.99k 1/16W 1%, 0402
AAC, CR05-4991FM
10
3
R4, R6, R9
RES., CHIP 100Ω 1/16W 5%, 0402
VISHAY, CRCW0402101J
11
3
R5, R7, R12
RES., CHIP 7.5k 1/16W 5%, 0402
AAC, CR05-752JM
12
3
R8, R10, R11
RES., CHIP 10k 1/16W 5%, 0402
AAC, CR05-103JM
13
1
U1
I.C., LTC2607CDE, DFN12DE
LINEAR TECH., LTC2607CDE
14
1
U2
I.C., LTC2422CMS, MSOP10
LINEAR TECH., LTC2422CMS
15
1
U3
I.C., LT1790ACS6-5, SOT23-6
LINEAR TECH., LT1790ACS6-5 *
16
1
U4
I.C., LT1790ACS6-4.096, SOT23-6
LINEAR TECH., LT1790ACS6-4.096 **
17
1
U5
I.C., LT1790ACS6-2.5, SOT23-6
LINEAR TECH., LT1790ACS6-2.5
18
1
U6
I.C., 24LC025, TSSOP8
MICROCHIP, 24LC025-I/ST
19
1
U7
I.C., NC7WB66K8X, US8
FAIRCHILD, NC7WB66K8X
dc934af
4
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 representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
A
B
C
D
1
EEVCC
NC
EEGND
EESCL
EESDA
MISO
MOSI
SCK
CS
C1
1UF,10V
LDAC
E8
JP7
CA2
JP6
CA1
JP4
VCC CA0
+5V
2
1
CA2
SDA
C3
0.1UF,16V
SCL
LDAC
CA1
CA0
U1
LTC2607CDE
3 OE2
4 GND
1 1A
2 1B
VOUTB
VCC
REF
GND
REFLO
5
4
A1
A0
2
1
7
8
9
10
11
12
E9
REFLO
C12
0.1UF,16V
C10
100PF
R5
7.5K
C9
100PF
R7
7.5K
CH0
CH1
VREF
3
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
DRAWN:
KIM T.
DESIGNER:
OUT
OUT
1
5V REG
C
B
A
6
4
2
JP3
ADC
E7
E6
ENABLE
GND
GND
VREF
VCC
VOUTB
VOUTA
E5
E4
E2
E1
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900
Fax: (408)434-0507
LTC Confidential-For Customer Use Only
VCC
VREF
DISABLE
5V REF
JP1
VREF
JP2
VCC
HD2X3-079
4.096V 3
2.5V 5
5.0V
R8 R9
10K 100
SCK
C6
1UF,10V
C5
1UF,10V
C4
1UF,10V
TECHNOLOGY
SCHEMATIC
CS 7
GND 6
SDO
8
9
10
6
6
6
VCC +5V
1
2
DATE:
A
SIZE
1
SHEET
1
DC934A-LTC2607CDE
Monday, September 26, 2005
DWG NO.
OF 1
A
REV
16-BIT DUAL RAIL-TO-RAIL DAC WITH I2C INTERFACE
TITLE:
5 ZSSET
3 CH1
4 CH0
SCK
F0
U2
LTC2422CMS
IN
U5
LT1790ACS6-2.5
IN
1 VCC
2 FSSET
ENGINEER: MARK T.
APPROVED:
CHECKED:
OUT
U4
LT1790ACS6-4.096
APPROVALS
R4
100
R6
100
2
U3
LT1790ACS6-5
IN
CONTRACT NO.
VOUTB
VOUTA
C11
1UF,10V
4
4
4
VCC
C8
0.1UF,16V
V+
V+
V+
CUSTOMER NOTICE
3
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
CIRUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
VCC
C7
0.1UF,16V
VREF
REFLO
EXT JP5
GND
R11
10K
VCC
6 SCL A2 3
5 SDA VSS 4
8 VCC
7 WP
U6
24LC025
3. U7 MULTIPLEXES THE SPI AND I2C BUSSES AND IS FOR
COMPATIBILITY WITH THE DC590 CONTROLLER BOARD ONLY.
2. INSTALL SHUNTS ON JP1-JP7 PIN 1 AND 2.
1. ALL RESISTORS ARE IN OHMS, 0402.
ALL CAPACITORS ARE IN MICROFARADS, 0402.
5
6
7
8
VOUTA
2A
2B
OE1
VCC
U7 (NOTE 3)
NC7WB66K8X
SDA
6 CA2
5
LDAC 3
SCL 4
CA1
CA0
R10
10K
VCC
R1
R2
R3
4.99K 4.99K 4.99K
1%
1%
1%
C2
1UF,10V
4
NOTES: UNLESS OTHERWISE SPECIFIED
R12
7.5K
VCC
I2C ADDRESS
E3
PWR GND
14
12
11
9
10
MOSI 7
MISO 5
SCK
CS 6
4
5V 2
V+
J1
HD2X7-079-MOLEX
GND
3
GND
8
GND
13
GND
1
GND
1
GND
1
V+
GND
13
GND
2
GND
2
GND
2
5
A
B
C
D
DEMO MANUAL DC934A
Schematic Diagram
dc934af
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DEMO MANUAL DC934A
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 application engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation
dc934af
6
Linear Technology Corporation
LT 0613 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507 ● www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2013
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