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.