1 Features

• 8-channel, 18-bit ADC with analog front-end:

– Dual, simultaneous sampling: 4 × 1 channels

– Constant 1-MΩ input impedance front-end

• Programmable low-pass filter bandwidth:

– 21 kHz and 400 kHz

• Programmable input ranges:

– ±12 V, ±10 V, ±7 V, ±5 V, ±3.5 V, and ±2.5 V

– Single-ended and differential inputs

• Input overvoltage protection: Up to ±18 V

• Integrated low-drift 4.096-V precision reference

• Excellent performance:

– DNL: ±0.3 LSB, INL: ±1.5 LSB

– SNR: 92.2 dB, THD: –112 dB

• Power supply:

– Analog and digital: 5 V and 1.8 V

– Digital interface: 1.2 V to 1.8 V

• Temperature range: –40°C to +125°C

2 Applications

• Semiconductor test

• Battery test

• Data acquisition (DAQ).

3 Description

The ADS981x is an eight-channel data acquisition

(DAQ) system based on a dual, simultaneoussampling,

18-bit successive approximation register

(SAR) analog-to-digital converter (ADC). The

ADS981x features a complete analog front-end

for each channel with an input clamp, 1-MΩ

input impedance, independently programmable gain

amplifier (PGA), programmable low-pass filter, and an

ADC input driver. The device also features a low-drift,

precision reference with a buffer to drive the ADCs. A

high-speed digital interface supporting 1.2-V to 1.8-V

operation enables the ADS981x to be used with a

variety of host controllers.

The ADS981x can be configured to accept ±12-V,

±10-V, ±7-V, ±5-V, ±3.5-V, and ±2.5-V bipolar inputs.

The high input impedance allows direct connection

with sensors and transformers, thus eliminating the

need for external driver circuits. The high performance

and accuracy, along with zero-latency conversions

offered by this device make the ADS981x a great

choice for multiple industrial applications.