GENERAL DESCRIPTION

The AD7896 is a fast, 12-bit ADC that operates from a single 2.7 V to 5.5 V supply and is housed in small 8-lead PDIP and 8-lead SOIC packages. The part contains an 8 µs successive approximation ADC, an on-chip track-and-hold amplifier, an on-chip clock, and a high speed serial interface.

Output data from the AD7896 is provided via a high speed, serial interface port. This 2-wire serial interface has a serial clock input and a serial data output with the external serial clock accessing the serial data from the part.

In addition to the traditional dc accuracy specifications, such as linearity, full-scale, and offset errors, the AD7896 is also specified for dynamic performance parameters, including harmonic distortion and signal-to-noise ratio.

The part accepts an analog input range of 0 V to VDD and operates from a single 2.7 V to 5.5 V supply, consuming only 9 mW typical. The VDD input is also used as the reference for the part so that no external reference is required.

The AD7896 features a high sampling rate mode and, for low power applications, a proprietary automatic power-down mode where the part automatically goes into power-down once conver sion is complete and “wakes up” before the next conversion cycle.

The part is available in a small, 8-lead, 0.3 wide, plastic or hermetic dual-in-line package (PDIP) and in an 8-lead, small outline IC (SOIC).

FEATURES

100 kHz Throughput Rate

Fast 12-Bit Sampling ADC with 8 μs Conversion Time

8-Lead PDIP and SOIC

Single 2.7 V to 5.5 V Supply Operation

High Speed, Easy-to-Use Serial Interface

On-Chip Track-and-Hold Amplifier

Analog Input Range Is 0 V to Supply

High Input Impedance

Low Power: 9 mW Typ