Burr-Brown DAC7731 User Manual

DAC7731

SBAS249 – DECEMBER 2001

16-Bit, Voltage Output, Serial Input

DIGITAL-TO-ANALOG CONVERTER

DAC7731

FEATURES

● LOW POWER: 150mW MAXIMUM

● +10V INTERNAL REFERENCE

● UNIPOLAR OR BIPOLAR OPERATION

● SETTLING TIME: 5µs to ±0.003% FSR

● 16-BIT MONOTINICITY, –40°C TO +85°C

● ±10V, ±5V, OR +10V CONFIGURABLE VOLTAGE

OUTPUT

● RESET TO ZERO OR MID-SCALE

● DOUBLE-BUFFERED DATA INPUT

● DAISY-CHAIN FEATURE FOR MULTIPLE

DAC7731s ON A SINGLE BUS

● SMALL SSOP-24 PACKAGE

APPLICATIONS

● PROCESS CONTROL

● ATE PIN ELECTRONICS

● CLOSED-LOOP SERVO CONTROL

● MOTOR CONTROL

● DATA ACQUISITION SYSTEMS

DESCRIPTION

The DAC7731 is a 16-bit Digital-to-Analog Converter (DAC)
which provides 16 bits of monotonic performance over the
specified operating temperature range and offers a +10V
internal reference. Designed for automatic test equipment
and industrial process control applications, the DAC7731’s
output swing can be configured in a ±10V, ±5V, or +10V
range. The flexibility of the output configuration allows the
DAC7731 to provide both unipolar and bipolar operation by
pin strapping. The DAC7731 includes a high-speed output
amplifier with a maximum settling time of 5µs to ±0.003%
FSR for a 20V full-scale change and only consumes 100mW
(typical) of power.

The DAC7731 features a standard 3-wire, SPI-compatible
serial interface with double buffering to allow asynchronous
updates of the analog output as well as a serial data output
line for daisy-chaining multiple DAC7731’s. A user program­mable reset control forces the DAC output to either min-scale
(0000

) or mid-scale (8000H), overriding both the input and

H

DAC register values. The DAC7731 is available in a
SSOP-24 package and three performance grades specified
to operate from –40°C to +85°C.

V

DDVSSVCC

REFEN

RSTSEL

RST

LDAC

SCLK

CS

SDO

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.

Enable

SDI

AGND DGND

REFADJ

Control

Logic

Input

Register

REF

+10V

Reference

Register

REF

OUT

DAC

www.ti.com

IN

Buffer

V

DAC

REF

R

OFFSET

RFB2

RFB1

SJ

V

OUT

Copyright © 2001, Texas Instruments Incorporated

ABSOLUTE MAXIMUM RATINGS

V

to VSS...........................................................................–0.3V to +32V

CC

V

to AGND ...................................................................... –0.3V to +16V

CC

V

to AGND ...................................................................... –16V to +0.3V

SS

AGND

to DGND................................................................... –0.3V to 0.3V

REF

to AGND .............................................................. 0V to VCC – 1.4V

IN

V

to DGND ........................................................................ –0.3V to +6V

DD

Digital Input Voltage to DGND ................................. –0.3V to V

Digital Output Voltage to DGND .............................. –0.3V to V

Operating Temperature Range ........................................ –40°C to +85°C

Storage Temperature Range ......................................... –65°C to +150°C

Junction Temperature (TJ Max) .................................................... +150°C

NOTE: (1) Stresses above those listed under “Absolute Maximum Ratings”
may cause permanent damage to the device. Exposure to absolute maximum
conditions for extended periods may affect device reliability.

(1)

ELECTROSTATIC
DISCHARGE SENSITIVITY

This integrated circuit can be damaged by ESD. Texas Instru­ments recommends that all integrated circuits be handled with

+ 0.3V

DD

+ 0.3V

DD

appropriate precautions. Failure to observe proper handling
and installation procedures can cause damage.

ESD damage can range from subtle performance degradation
to complete device failure. Precision integrated circuits may be
more susceptible to damage because very small parametric
changes could cause the device not to meet its published
specifications.

PACKAGE/ORDERING INFORMATION

PRODUCT PACKAGE-LEAD DESIGNATOR

PACKAGE TEMPERATURE PACKAGE ORDERING TRANSPORT

DAC7731E SSOP-24 DB –40°C to +85°C DAC7731E DAC7731E Rails, 60

(1)

"" " " "DAC7731E/1K Tape and Reel,1000

DAC7731EB SSOP-24 DB –40°C to +85°C DAC7731EB DAC7731EB Rails, 60

"" " " "DAC7731EB/1K Tape and Reel, 1000

DAC7731EC SSOP-24 DB –40°C to +85°C DAC7731EC DAC7731EC Rails, 60

"" " " "DAC7731EC/1K Tape and Reel, 1000

NOTE: (1) For the most current specifications and package information, refer to our web site at www.ti.com. (2) Models with a slash (/) are available only in Tape and
Reel in the quantities indicated (e.g., /1K indicates 1000 devices per reel). Ordering 1000 pieces of “DAC7731EC/1K” will get a single 1000-piece Tape and Reel.

SPECIFIED

RANGE MARKING NUMBER

(2)

MEDIA, QUANTITY

ELECTRICAL CHARACTERISTICS

All specifications at TA = T

PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX MIN TYP MAX UNITS
ACCURACY

Linearity Error (INL) ±6 ±4 ±3LSB

Differential Linearity Error
Monotonicity 14 15 16 Bits
Offset Error
Offset Error Drift
Gain Error With Internal REF ±0.4 ±0.25 ±0.15 % of FSR

Gain Error Drift With Internal REF ±15 ±10 ±7 ppm/°C
PSRR (V

ANALOG OUTPUT

Voltage Output

Output Current ±5 ✻✻ mA
Output Impeadance 0.1 ✻✻Ω
Maximum Load Capacitance 200 ✻✻pF
Short-Circuit Current ±15 ✻✻mA
Short-Circuit Duration AGND Indefinite ✻✻

REFERENCE

Reference Output 9.96 10 10.04 9.975 ✻ 10.025 ✻✻✻ V
REF
REF
REF
REF
REF
REFADJ Input Range

REFADJ Input Impedance 50
V

REF

V

REF

or VSS) At Full-Scale 50 200 ✻✻ ✻✻ppm/V

CC

(2)

Impedance 400 ✻✻Ω

OUT

Voltage Drift ±15 ±10 ±7 ppm/°C

OUT

Voltage Adjustment

OUT

Input Range

IN

Input Current 10 ✻✻nA

IN

Output Current –2+2✻✻✻ ✻mA
Impedance 1 ✻✻Ω

to T

MIN

(DNL)

(1)

(4)

, VCC = +15V, VSS = –15V, VDD = +5V, Internal refi⁄ence enabled, unless otherwise noted.

MAX

DAC7731E DAC7731EB DAC7731EC

TA = 25°C ±5 ±3 ±2LSB

±2 ✻✻ppm/°C

With External REF ±0.25 ±0.1 ✻ % of FSR

+11.4/–4.75 0 to 10 ✻✻V
+11.4/–11.4 ±10 ✻✻V

+11.4/–6.4 ±5 ✻✻V

(3)

Absolute Max Value that

can be applied is V

±25 ✻✻ mV

4.75 V

010✻✻✻✻V

CC

±4 ±2 ±1LSB

±0.1 ✻✻% of FSR

– 1.4 ✻✻✻✻V

CC

✻✻kΩ

2

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DAC7731

SBAS249

ELECTRICAL CHARACTERISTICS (Cont.)

All specifications at TA = T

PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX MIN TYP MAX UNITS
DYNAMIC PERFORMANCE

Settling Time to ±0.003% 20V Output Step 3 5 ✻✻ ✻✻ µs

Digital Feedthrough 2 ✻✻nV-s
Output Noise Voltage at 10kHz 100 ✻✻nV/√Hz

DIGITAL INPUT

V

IH

V

IL

DIGITAL OUTPUT

V

OH

V

OL

POWER SUPPLY

V

DD

V

CC

V

SS

I

DD

I

CC

I

SS

Power

TEMPERATURE RANGE

Specified Performance –40 +85 ✻✻✻ ✻°C

✻ Specifications same as grade to the left.

NOTES: (1)

With minimum VCC/VSS requirements, internal reference enabled. (2) Please refer to the "Theory of Operation" section for more information with respect to output voltage
configurations. (3) See Figure 11 for gain and offset adjustment connection diagrams when using the internal reference. (4) The minimum value for REF
of V

+14V and +4.75V, where +4.75V is the minimum voltage allowed. (5) Reference low-pass filter values: 100kΩ, 1.0µF (see Figure 14).

SS

to T

MIN

, VCC = +15V, VSS = –15V, VDD = +5V, Internal reference enabled, unless otherwise noted.

MAX

R

= 5kΩ, CL = 200pF,

L

with external REF

to REF

|IH| < 10µA0.7 • V
|IL| < 10µA0.3 • V

OUT

(5)

filter

IN

DD

IOH = –0.8mA 3.6 ✻✻ V

IOL = 1.6mA 0.4 ✻✻V

+4.75 +5.0 +5.25 ✻✻✻✻✻✻ V
+11.4 +15.75 ✻✻✻✻V

Bipolar Operation –15.75 –11.4 ✻✻✻✻V

Unipolar Opeation –15.75 –4.75 ✻✻✻✻V

Unloaded 4 6 ✻✻ ✻✻ mA

Unloaded –4 –2.5 ✻✻ ✻✻ mA
No Load, Ext. Reference
No Load, Int. Reference 100 150

DAC7731E DAC7731EB DAC7731EC

✻✻ V

DD

✻✻V

100 ✻✻µA

85 ✻✻mW

✻✻ ✻✻mW

must be equal to the greater

IN

PIN CONFIGURATION

Top View SSOP

V

1

CC

REF

REFADJ

R

OFFSET

AGND

OUT

REF

V

REF

RFB2
RFB1

V

OUT

V

SJ

2
3

IN

4
5
6

DAC7731

7
8
9

10

11

12

DD

NOTE: (1) RST, LDAC, SDI, CS and SCK are Schmitt-triggered inputs.

24
23
22
21
20
19
18
17
16
15
14
13

V

SS

REFEN
RSTSEL
SCLK
CS
SDO
SDI
LDAC
RST
NC
TEST
DGND

PIN DESCRIPTIONS

PIN NAME DESCRIPTION

1V
2REF
3 REF
4 REFADJ Internal Reference Trim. (Acts as a gain adjustment

5V

6R

OFFSET

7 AGND Analog ground
8 RFB2 Feedback Resistor 2, used to configure DAC output

9 RFB1 Feedback Resistor 1, used to configure DAC output

10 SJ Summing Junction of the Output Amplifier
11 V
12 V
13 DGND Digital Ground
14 TEST Reserved, Connect to DGND
15 NC No Connection
16 RST V

17 LDAC DAC register load control, rising dege triggered. Data

18 SDI Serial Data Input. Data is latched into the input

19 SDO Serial Data Output, delayed 16 SCLK clock cycles.
20 CS Chip Select, Active LOW
21 SCLK Serial Clock Input
22 RSTSEL Reset Select; determines the action of RST. If HIGH,

23 REFEN Enables internal +10V reference (REF

24 V

Positive Analog Power Supply

CC

Internal Reference Output

OUT

Reference Input

IN

input when the internal reference is used.)
Buffered Output from REFIN, can be used to drive

REF

external devices. Internally, this pin directly drives the
DAC's circuitry.
Offsetting Resistor

range.

range.

DAC Voltage Output

OUT

Digital Power Supply

DD

reset; active LOW, depending on the state of

OUT

RSTSEL, the DAC register is either reset to mid­scale or min-scale.

is loaded from the input register to the DAC register.

register on the rising edge of SCLK.

RST will reset the DAC register to mid-scale. If LOW,
RST will reset the DAC register to min-scale.

LOW.
Negative Analog Power Supply

SS

OUT

), active

DAC7731

SBAS249

www.ti.com

3

TIMING CHARACTERISTICS

VCC = +15V, V

PARAMETER DESCRIPTION MIN TYP MAX UNITS

t

WH

t

WL

t

SDI

t

HDI

t

SCS

t

HSC

t

DDO

t

HDO

t

DDOZ

t

WCSH

t

WLDL

t

WLDH

t

SLD

t

DLD

t

SCLK

t

SRS

t

HRS

t

WRL

t

INTERFACE TIMING

= –15V, VDD = 5V; RL = 2kΩ to AGND; CL = 200pF to AGND; all specifications –40°C to +85°C, unless otherwise noted.

SS

DAC7731

SCLK HIGH Time 25 ns
SCLK LOW Time 25 ns
Setup Time: Data in valid before rising SCLK 5 ns
Hold Time: Data in valid after rising SCLK 20 ns
Setup Time: CS falling edge before first rising SCLK 15 ns
Hold Time: CS rising edge after 16th rising SCLK 0 ns
Delay Time: CS Falling Edge to Data Out valid, CL = 20pF on SDO 50 ns
Hold Time: Data Out valid after SCLK rising edge, CL 20pF on SDO 50 ns
Delay Time: CS rising edge to SDO = High Impedance 70 ns
CS HIGH Time 50 ns
LDAC LOW Time 20 ns
LDAC HIGH Time 20 ns
Setup Time: 16th Rising SCLK Before LDAC Rising Edge 15 ns
Delay Time: LDAC rising edge to first SCLK rising edge of next 15 ns
transfer cycle.
Setup Time: CS High before falling SCLK edge following 16th 5 ns
rising SCLK edge
Setup Time: RSTSEL Valid Before RST LOW 0 ns
Hold Time: RSTSEL valid after RST HIGH 20 ns
RST LOW Time 30 ns

S

DAC V

Settling Time 5 µs

OUT

SCLK

SDO

LDAC

V

RESET TIMING

SDI

OUT

CS

t

SCS

t

WH

12 16

t

Word B

Word A

t

SRS

WL

t

t

HDI

HDO

t

SDI

B15 B14 B13 B0

t

DDO

A15 A14 A13 A0

RSTSEL

RST

+FS

(RSTSEL = LOW)

V

OUT

–FS
+FS

(RSTSEL = HIGH)

V

OUT

–FS

t

HCS

t

t

HRS

WRL

t

DDOZ

t

WCSH

t

SCLK

C15 C14 C13 C12

Word C

B15 B14 B13 B12

t

t

WLDL

t

SLD

DLD

t

WLDH

±0.003% of FSR

Error Bands

t

S

t

S

Word B

Min-Scale

Mid-Scale

4

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DAC7731

SBAS249

TYPICAL CHARACTERISTICS

TA = +25°C (unless otherwise noted).

6
4
2
0

–2

INL (LSB)

Bipolar Configuration: V

–4

T

= 85°C, Internal Reference Enabled

A

–6

2.0

1.5

1.0

0.5

0.0

–0.5

DNL (LSB)

–1.0
–1.5
–2.0

0000

H

6
4
2
0

–2

INL (LSB)

Bipolar Configuration: V

–4

T

= –40°C, Internal Reference Enabled

A

–6

2.0

1.5

1.0

0.5

0.0

–0.5

DNL (LSB)

–1.0
–1.5
–2.0

0000

H

LINEARITY ERROR AND DIFFERENTIAL

LINEARITY ERROR vs DIGITAL INPUT CODE

= –10V to +10V

OUT

2000H4000H6000H8000

A000

H

C000HE000HFFFF

H

Digital Input Code

LINEARITY ERROR AND DIFFERENTIAL

LINEARITY ERROR vs DIGITAL INPUT CODE

= –10V to +10V

OUT

2000H4000H6000H8000

H

A000

C000HE000HFFFF

H

Digital Input Code

LINEARITY ERROR AND DIFFERENTIAL

6

LINEARITY ERROR vs DIGITAL INPUT CODE

4
2
0

–2

INL (LSB)

Bipolar Configuration: V

–4

T

= 25°C, Internal Reference

A

–6

2.0

1.5

1.0

0.5

0.0

–0.5

DNL (LSB)

–1.0
–1.5
–2.0

H

2000H4000H6000H8000

0000

H

= –10V to +10V

OUT

Enabled

A000

H

C000HE000HFFFF

H

H

Digital Input Code

1.00

OFFSET ERROR vs TEMPERATURE

0.75
V

= –10 to +10V

0.50

0.25

V

OUT

= 0 to +10V

OUT

0.00

–0.25

Error (mV)

–0.50
–0.75
–1.00

H

–40 –15 10 35 60 85

Temperature (°C)

0.000

–0.010
–0.020
–0.030
–0.040
–0.050

Error (%)

–0.060

Ext. Ref, Unipolar Mode: V

Int. Ref, Unipolar Mode: V

GAIN ERROR vs TEMPERATURE

= 0 to +10V

OUT

Ext. Ref, Bipolar Mode: V

= 0 to +10V

OUT

–0.070
–0.080
–0.090
–0.100

Load = 200pF, 2kΩ

Int. Ref, Bipolar Mode: V

–40 –15 10 35 60 85

Temperature (°C)

DAC7731

SBAS249

= –10 to +10V

OUT

= –10 to +10V

OUT

www.ti.com

VCC SUPPLY CURRENT vs DIGITAL INPUT CODE

4.4

4.3

Bipolar Configuration: V
Internal Reference Enabled, T

4.2

4.1

(mA)

4.0

CC

I

3.9

3.8

3.7

0000H2000H4000H6000H8000

A000

H

Digital Input Code

= –10V to +10V

OUT

= 25°C

A

C000HE000HFFFF

H

H

5

TYPICAL CHARACTERISTICS (Cont.)

TA = +25°C (unless otherwise noted).

VCC SUPPLY CURRENT vs DIGITAL INPUT CODE

3.4

3.3

Bipolar Configuration: V
External Reference, REFEN = 5V, T

= –10V to +10V

OUT

3.2

3.1

(mA)

3.0

CC

I

2.9

2.8

2.7

0000H2000H4000H6000H8000

A000

H

C000HE000HFFFF

H

Digital Input Code

7
6
5

SUPPLY CURRENT vs TEMPERATURE

Load Current Excluded
V

= +15V, VSS = –15V

CC

Bipolar V

Configuration: –10V to +10V

OUT

4
3

I

(mA)

SS

, I

CC

I

–1
–2

CC

2
1
0

I

SS

–3

–40 –15 10 35 60 85

Temperature (°C)

= 25°C

A

–1.50

VSS SUPPLY CURRENT vs DIGITAL INPUT CODE

–1.75

–2.00

(mA)

SS

I

–2.25

–2.50

Bipolar Configuration: V
T

= 25°C

–2.75

H

A

0000H2000H4000H6000H8000

= –10V to +10V

OUT

A000

H

C000HE000HFFFF

H

H

Digital Input Code

1800
1600
1400
1200

SUPPLY CURRENT vs LOGIC INPUT VOLTAGE

TA = 25°C, Transition
Shown for a Single
Input (Applies to CS,
SCLK,D
inputs)

and LDAC

IN

1000

(µA)

800

DD

I

600
400
200

0

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
V

(V)

LOGIC

HISTOGRAM OF VCC CURRENT CONSUMPTION

100

Bipolar Output Configuration

90

Internal Reference Enabled
Code = 5555

80

H

70
60
50
40

Frequency

30
20
10

0

3.000 3.500 4.000 4.500 5.000
(mA)

I

CC

6

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100

HISTOGRAM OF VSS CURRENT CONSUMPTION

Bipolar Output Configuration

90

Internal Reference Enabled
Code = 5555

80

H

70
60
50
40

Frequency

30
20
10

0

–3.50 –3.00 –2.50 –2.00 –1.50

I

(mA)

SS

DAC7731

SBAS249