GENERAL DESCRIPTION

The AD7892 is a high speed, low power, 12-bit A/D converter that operates from a single +5 V supply. The part contains a 1.47 µs successive approximation ADC, an on-chip track/hold amplifier, an internal +2.5 V reference and on-chip versatile interface structures that allow both serial and parallel connection to a microprocessor. The part accepts an analog input range of ±10 V or ±5 V (AD7892-1), 0 V to +2.5 V (AD7892-2) and ±2.5 V (AD7892-3). Overvoltage protection on the analog inputs for the AD7892-1 and AD7892-3 allows the input voltage to go to ±17 V or ±7 V respectively without damaging the ports.

The AD7892 offers a choice of two data output formats: a single, parallel, 12-bit word or serial data. Fast bus access times and standard control inputs ensure easy parallel interface to microprocessors and digital signal processors. A high speed serial interface allows direct connection to the serial ports of microcontrollers and digital signal processors.

In addition to the traditional dc accuracy specifications such as linearity, full-scale and offset errors, the part is also specified for dynamic performance parameters including harmonic distortion and signal-to-noise ratio.

The AD7892 is fabricated in Analog Devices’ Linear Compat ible CMOS (LC2MOS) process, a mixed technology process that combines precision bipolar circuits with low power CMOS logic. It is available in a 24-lead, 0.3 wide, plastic or hermetic DIP or in a 24-lead SOIC.

FEATURES

Fast 12-Bit ADC with 1.47 s Conversion Time

600 kSPS Throughput Rate (AD7892-3)

500 kSPS Throughput Rate (AD7892-1, AD7892-2)

Single Supply Operation

On-Chip Track/Hold Amplifier

Selection of Input Ranges:

±10 V or ±5 V for AD7892-1

0 V to +2.5 V for AD7892-2

±2.5 V for AD7892-3

High Speed Serial and Parallel Interface

Low Power, 60 mW typ

Overvoltage Protection on Analog Inputs (AD7892-1

and AD7892-3)