Analog Devices AD7836 a Datasheet

LC2MOS

a

FEATURES
Four 14-Bit DACs in One Package
Voltage Outputs
Separate Offset Adjust for Each Output
Reference Range of 5 V
Maximum Output Voltage Range of 10 V
Clear Function to User-Defined Code
44-Pin MQFP Package

APPLICATIONS
Process Control
Automatic Test Equipment
General Purpose Instrumentation

Quad 14-Bit DAC

AD7836

GENERAL DESCRIPTION

The AD7836 contains four 14-bit DACs on one monolithic
chip. It has output voltages with a full-scale range of ±10 V
from reference voltages of ±5 V.

The AD7836 accepts 14-bit parallel loaded data from the exter­nal bus into one of the input latches under the control of the
WR, CS and DAC channel address pins, A0–A2.

The DAC outputs are updated individually, on reception of new
data. In addition, the SEL input can be used to apply the user
programmed value in DAC Register E to all DACs, thus setting
all DAC output voltages to the same level. The contents of the
DAC data registers are not affected by the SEL input.

Each DAC output is buffered with a gain of two amplifier into
which an external DAC offset voltage can be inserted via the
DUTGNDx pins.

The AD7836 is available in a 44-lead MQFP package.

FUNCTIONAL BLOCK DIAGRAM

DB13

DB0

WR

(+)A

REF

X1 X1

DAC A

DAC D

X1 X1

(+)D V

REF

V

REF

REF

(–)A V

(–)D V

(+)B V

REF

X1

DAC B

DAC B

X1 X1

(+)C V

REF

REF

REF

(–)B

V

A

X1

(–)C

CLR

R

R

R

R

R

R

R

R

OUT

DUTGND A

V

B

OUT

DUTGND B

C

V

OUT

DUTGND C

V

D

OUT

DUTGND D

MUX

MUX

MUX

MUX

SELAGNDDGND

V

V

V

CCVSSVDD

AD7836

14

INPUT

BUFFER

CS

A0

A1

A2

ADDRESS

DECODE

14 14

DATA

14

DATA

DATA

DATA

DATA

REG

A

REG

B

REG

C

REG

D

REG

E

14

REV. A

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reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] World Wide Web Site: http://www.analog.com
Fax: [phone] © Analog Devices, Inc., 1999

(VCC = +5 V  5%; VDD = +15 V  5%; VSS = –15 V  5%; AGND = DGND = DUTGND

AD7836–SPECIFICATIONS

= 0 V; RL = 5 k and CL = 50 pF to GND, T

Parameter A Units Test Conditions/Comments

ACCURACY

Resolution 14 Bits
Relative Accuracy ±2 LSB max
Differential Nonlinearity ±0.9 LSB max Guaranteed Monotonic Over Temperature
Full-Scale Error ±8 LSB max V
Zero-Scale Error ±8 LSB max V
Gain Error ±2 mV typ V
Gain Temperature Coefficient

DC Crosstalk

2

2

20 ppm FSR/°C typ
40 ppm FSR/°C max
50 µV max See Terminology. RL = 5 kΩ

(+) = +5 V, V

REF

(+) = +5 V, V

REF

(+) = +5 V, V

REF

REFERENCE INPUTS

DC Input Resistance 100 MΩ typ
Input Current ±1 µA max Per Input. Typically ±20 nA

(+) Range 0/+5 V min/max

V

REF

V

(–) Range –5/0 V min/max

REF

[V

REF

(+) – V

(–)] 2/10 V min/max For Specified Performance. Can Go as Low as 0 V,

REF

but Performance Not Guaranteed

OUTPUT CHARACTERISTICS

Output Voltage Swing ±10 V min 2 × (V

REF

(–)+[V

Short Circuit Current 25 mA max
Resistive Load 5 kΩ min To 0 V
Capacitive Load 50 pF max To 0 V

DIGITAL INPUTS

, Input High Voltage 2.4 V min

V

INH

, Input Low Voltage 0.8 V max

V

INL

, Input Current ±10 µA max Total for All Pins

I

INH

CIN, Input Capacitance 10 pF max

POWER REQUIREMENTS

V

CC

V

DD

V

SS

5.0 V nom ±5% for Specified Performance

15.0 V nom ±5% for Specified Performance
–15.0 V nom ±5% for Specified Performance

Power Supply Sensitivity

∆Full Scale/∆V
∆Full Scale/∆V

I

CC

I

DD

I

SS

DD

SS

110 dB typ
100 dB typ

0.5 mA max V
8 mA max V

= VCC, V

INH

= 2.4 V min, V

INH

14 mA max Outputs Unloaded. Typically 7 mA
14 mA max Outputs Unloaded. Typically 7 mA

1

= T

to T

A

MIN

(–) = –5 V. Typically within ±1 LSB

REF

(–) = –5 V. Typically within ±1 LSB

REF

(–) = –5 V

REF

(+)-V

REF

INL

REF

= DGND. Dynamic Current

= 0.8 V max

INL

, unless otherwise noted)

MAX

(–)]•D) – V

DUTDGN

(These characteristics are included for Design Guidance and are not

AC PERFORMANCE CHARACTERISTICS

Parameter A Units Test Conditions/Comments

DYNAMIC PERFORMANCE

Output Voltage Settling Time 16 µs typ Full-Scale Change to ±1/2 LSB. DAC Latch Contents Alternately

Digital-to-Analog Glitch Impulse 150 nV-s typ Measured with V

DC Output Impedance 0.3 Ω max See Terminology
Channel-to-Channel Isolation 115 dB typ See Terminology
DAC-to-DAC Crosstalk 10 nV-s typ See Terminology
Digital Crosstalk 10 nV-s typ Feedthrough to DAC Output Under Test Due to Change in Digital

Digital Feedthrough 0.2 nV-s typ Effect of Input Bus Activity on DAC Output Under Test
Output Noise Spectral Density

@ 1 kHz 40 nV/√Hz typ All 1s Loaded to DAC. V

NOTES

1

Temperature range for A Version: –40°C to +85°C

2

Guaranteed by design.

Specifications subject to change without notice.

subject to production testing.)

Loaded with All 0s and All 1s

REF

Alternately Loaded with 1FFF Hex and 2000 Hex. Not Dependent
on Load Conditions

Input Code to Another Converter

–2–

(+) = +5 V, V

(+) = V

REF

(–) = –5 V. DAC Latch

REF

(–) = 0 V

REF

REV. A

TIMING SPECIFICATIONS

1

(VCC = +5 V  5%; VDD = +15 V  5%; VSS = –15 V  5%; AGND = DGND = 0 V)

AD7836

Parameter Limit at T

t

1

t

2

t

3

t

4

t

5

t

6

t

7

t

8

t

9

t

10

NOTES

1

All input signals are specified with tr = tf = 5 ns (10% to 90% of 5 V) and timed from a voltage level of 1.6 V.

2

Rise and fall times should be no longer than 50 ns.

Specifications subject to change without notice.

15 ns min A0, A1, A2 to WR Setup Time
0 ns min A0, A1, A2 to WR Hold Time
0 ns min CS to WR Setup Time
0 ns min WR to CS Hold Time
44 ns min WR Pulsewidth
15 ns min Data Setup Time

4.5 ns min Data Hold Time
44 ns min WR Pulse Interval
16 µs typ Settling Time
300 ns max CLR Pulse Activation Time

A0, A1, A2

CS

WR

DATA

MIN, TMAX

t

3

t

1

t

5

t

6

Units Description

t

2

t

4

t

8

t

7

t

9

V

OUT

t

CLR

V

OUT

10

Figure 1. Timing Diagram

REV. A

–3–

AD7836

ABSOLUTE MAXIMUM RATINGS

(TA = +25°C unless otherwise noted)

VCC to DGND . . . . . . . . . . . . . . .–0.3 V, +7 V or V

1

+ 0.3 V

DD

(Whichever Is Lower)

to AGND . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V, +17 V

V

DD

V

to AGND . . . . . . . . . . . . . . . . . . . . . . . . . . +0.3 V, –17 V

SS

AGND to DGND . . . . . . . . . . . . . . . . . . . . . . –0.3 V, +0.3 V

Digital Inputs to DGND . . . . . . . . . . . . . –0.3 V, V

V

(+) to V

REF

V

(+) to AGND . . . . . . . . . . . . . . VSS – 0.3 V, VDD + 0.3 V

REF

(–) to AGND . . . . . . . . . . . . . . VSS – 0.3 V, VDD + 0.3 V

V

REF

DUTGND to AGND . . . . . . . . . . . V

V

(A–D) to AGND . . . . . . . . . . VSS – 0.3 V, VDD + 0.3 V

OUT

(–) . . . . . . . . . . . . . . . . . . . . . . –0.3 V, +18 V

REF

– 0.3 V, VDD + 0.3 V

SS

+ 0.3 V

CC

Operating Temperature Range

Industrial (A Version) . . . . . . . . . . . . . . . . –40°C to +85°C

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

Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . .+150°C

ORDERING GUIDE

Temperature Error DNL Package

Model Range (LSBs) (LSBs) Option*

AD7836AS –40°C to +85°C ±2 ±0.9 S-44

*S = Plastic Quad Flatpack (MQFP).

MQFP Package, Power Dissipation . . . . . . . . . . . . . . 480 mW

Thermal Impedance . . . . . . . . . . . . . . . . . . . . . 95°C/W

θ

JA

Lead Temperature, Soldering

Vapor Phase (60 sec) . . . . . . . . . . . . . . . . . . . . . . . .+215°C

Infrared (15 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . . .+220°C

NOTES

1

Stresses above those listed under “Absolute Maximum Ratings” may cause

permanent damage to the device. This is a stress rating only and functional
operation of the device at these or any other conditions above those indicated in
the operational section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.

2

Transient currents of up to 100 mA will not cause SCR latch-up.

Linearity

CAUTION

ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection.
Although the AD7836 features proprietary ESD protection circuitry, permanent damage may
occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD
precautions are recommended to avoid performance degradation or loss of functionality.

WARNING!

ESD SENSITIVE DEVICE

–4–

REV. A