GENERAL DESCRIPTION

The AD7713 is a complete analog front end for low frequency measurement applications. The device accepts low level signals directly from a transducer or high level signals (4
VREF) and outputs a serial digital word. It employs - conversion technique to realize up to 24 bits of no missing codes performance. The input signal is applied to a proprietary programmable gain front end based around an analog modulator. The modulator output is processed by an on-chip digital filter. The first notch of this digital filter can be programmed via the on-chip control register, allowing adjustment of the filter cutoff and settling time.

FEATURES

Charge Balancing ADC

24 Bits No Missing Codes

±0.0015 Nonlinearity

3-Channel Programmable Gain Front End

Gains from 1 to 128

2 Differential Inputs

1 Single-Ended High Voltage Input

Low-Pass Filter with Programmable Filter Cutoffs

Ability to Read/Write Calibration Coefficients

Bidirectional Microcontroller Serial Interface

Single-Supply Operation

Low Power (3.5 mW typ) with Power-Down Mode (150 μW typ)

APPLICATIONS

Loop Powered (Smart) Transmitters

RTD Transducers

Process Control

Portable Industrial Instruments