DAC1280

Current Output

Differential DAC

Synchronization

CLK

SYNC

PWDN

DGND

AVSS

GAIN[2:0]

DVDD

AVDD

DAC1280

3

VREF

Bitstream

Source

V

OUT

External I/V Converter

DAC1280

www.ti.com

SBAS432A – APRIL 2010 – REVISED SEPTEMBER 2010

Low Distortion Digital-to-Analog Converter for Seismic Monitoring

Check for Samples: DAC1280

1

FEATURES

DESCRIPTION

2

•

Outstanding Performance:

The DAC1280 is a very low distortion digital-to-analog

converter (DAC) suited for performance testing of

–

THD: –125dB

seismic

equipment.

The

DAC1280

provides

a

–

SNR: 120dB (413Hz BW, Gain = 1/1)

high-accuracy output signal from a bitstream input.

–

Gain Error: 0.1%

The device achieves very high linearity in a small

•

Pin Operation: No Registers to Program

package while dissipating only 18mW. Together with

the

high-performance

ADS1281

and

ADS1282

•

Gain: 1/1 to 1/64

analog-to-digital converters (ADCs), these devices

•

SYNC Input for Phase Control

create a test and measurement system that meets

•

Power-Down Mode

the exacting demands of energy exploration and

seismic monitoring equipment.

•

Low Power: 18mW

•

Analog Supply: +5V or ±2.5V

The DAC1280 is designed to match the system

components (power supply, clock and reference

•

Digital Supply: 1.8V to 3.3V

voltage) of the companion ADCs, the ADS1281 and

•

Small 16-Pin TSSOP Package

ADS1282. The input to the DAC1280 is a 1s density

•

Temperature Range: –40°C to +85°C

modulated bitstream. The DAC1280 output is a

differential current intended for use with an active I/V

converter. The I/V converter provides a voltage output

APPLICATIONS

suitable for performance testing of sensors and

•

Energy Exploration Equipment

ADCs.

•

Seismic Monitoring Systems

Three gain control pins set the output range in 6dB

steps

from

0dB

to

–36db

(±2.5V

to

±0.039V

differential). The attenuation ranges match the gains

of the ADS1282 for testing at all gains. The DAC

uses a reference voltage and bias resistor to set the

full-scale output. The resistor can be adjusted to

fine-trim the DAC full-scale.

The SYNC pin aligns the input data sampling to the

CLK phase. A power-down pin shuts down the device

when not in use. The DAC1280 is available in a

small, 16-pin TSSOP package and is fully specified

for operation over –40°C to +85°C temperature range

with a maximum operating temperature of +125°C.

1

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.

2

All trademarks are the property of their respective owners.

PRODUCTION DATA information is current as of publication date.

Copyright © 2010, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.