1 Features

1• Single-Chip Test Signal Generator

• Buffered Voltage Output

• High Performance:

– THD: –125 dB (G = 1/1 to 1/8)

– SNR: 120 dB (413 Hz BW, G = 1/1)

• Analog and Digital Gain Control

• Output Frequency: 0.488 Hz to 250 Hz

• Sine, Pulse, and DC Modes

• Digital Data Input Mode

• Low On-Resistance Signal Switch

• Sync Input

• Power-Down Mode

• Analog Supply: 5 V or ±2.5 V

• Digital Supply: 1.8 V to 3.3 V

• Power: 38 mW

• Package: TSSOP-24

• Operating Range: –50°C to +125°C

2 Applications

• Energy Exploration

• Seismic Monitoring Systems

• High-Accuracy Instrumentation

3 Description

The DAC1282 is a fully-integrated digital-to-analog

converter (DAC) providing low distortion, digital synthesized voltage output suitable for testing of

seismic equipment. The DAC1282 achieves very high

performance in a small package with low power.

Together, with the high-performance ADS1281 and ADS1282 analog-to-digital converters (ADCs), these

devices create a measurement system that meets the

exacting demands of seismic data acquisition

equipment.

The DAC1282 integrates a digital signal generator, a

DAC, and an output amplifier providing sine wave, dc,

and pulse output voltages.

The output frequency is programmable from 0.5 Hz to 250 Hz and the magnitude is scaled by both analog

and digital control. The analog gain is adjustable in 6-

dB steps and the digital gain in 0.5-dB steps. The

analog gain settings match those of the ADS1282 for

testing at all gains with high resolution.

The DAC1282 also provides pulse outputs. The pulse

amplitude is user-programmed and then selected by

the pin for precise timing. Custom output signals can be generated by applying an external bitstream

pattern.

A signal switch can be used to connect the DAC

output to sensors for THD and impulse testing. The

switch timing is controlled by pin and by command.

A SYNC pin synchronizes the DAC output to the

analog-to-digital converter (ADC) sample interval. A

power-down input disables the device, reducing

power consumption to microwatts.