GENERAL DESCRIPTION

The AD7982 is an 18-bit, successive approximation, analog-to-digital converter (ADC) that operates from a single power supply, VDD. The AD7982 contains a low power, high speed, 18-bit sampling ADC and a versatile serial interface port. On the CNV rising edge, the AD7982 samples the voltage difference between the IN+ and IN− pins. The voltages on these pins usually swing in opposite phases between 0 V and VREF. The reference voltage, VREF, is applied externally and can be set independent of the supply voltage, VDD. Its power scales linearly with throughput.

FEATURES

High performance

True differential analog input range: ±VREF

0 V to VREF with VREF between 2.5 V to 5 V

Easy to drive with the ADA4941-1 or ADA4940-1

Throughput: 1 MSPS

Zero latency architecture

18-bit resolution with no missing codes

INL: ±1 LSB typical, ±2 LSB maximum

Dynamic range: 99 dB, VREF = 5 V

SNR: 98 dB at fIN = 1 kHz, VREF = 5 V

THD: −119 dB at fIN = 1 kHz, VREF = 5 V

SINAD: 97 dB at fIN = 1 kHz, VREF = 5 V

Low power dissipation

Single-supply 2.5 V operation with 1.8 V, 2.5 V, 3 V, and

5 V logic interface

4 mW at 1 MSPS (VDD only)

7 mW at 1 MSPS (total)

70 μW at 10 kSPS

Proprietary serial interface

SPI-/QSPI™/ MICROWIRE™-/DSP-compatible1

Ability to daisy-chain multiple ADCs and busy indicator

10-lead MSOP and 3 mm × 3 mm 10-lead LFCSP

Wide operating temperature range: −40°C to +85°C

APPLICATIONS

Automated test equipment

Data acquisition systems

Medical instruments

Machine automation