CMOS, Complete 14-Bit Analog I/O System

The AD7869 is a complete 14-bit I/O system containing a DAC and an ADC. The ADC is a successive approximation type with a track-and-hold amplifier, having a combined throughput rate of 83 kHz. The DAC has an output buffer amplifier with a settling time of 4 µs to 14 bits. Temperature compensated 3 V buried Zener references provide precision references for the DAC and ADC.

Interfacing to both the DAC and ADC is serial, minimizing pin count and giving a small 24-pin package size. Standard control signals allow serial interfacing to most DSP machines. Asynchronous ADC conversion control and DAC updating is made possible with the CONVST and LDAC logic inputs.

The AD7869 operates from ±5 V power supplies; the analog input/ output range of the ADC/DAC is ±3 V. The part is fully specified for dynamic parameters such as signal-to-noise ratio and harmonic distortion as well as traditional dc specifications.

The part is available in a 24-pin, 0.3 inch wide, plastic or hermetic dual-in-line package (DIP) and in a 28-pin, plastic SOIC package.

APPLICATIONS

* Digital Signal Processing

* Speech Recognition and Synthesis

* Spectrum Analysis

* High Speed Modems

* DSP Servo Control

PRODUCT HIGHLIGHTS

* Complete 14-Bit I/O System.

The AD7869 contains a 14-bit ADC with a track-and-hold amplifier and a 14-bit DAC with output amplifier. Also included are separate on-chip voltage references for the DAC and the ADC.

* Dynamic Specifications for DSP Users.

In addition to traditional dc specifications, the AD7869 is specified for ac parameters, including signal-to-noise ratio and harmonic distortion. These parameters, along with important timing parameters, are tested on every device.

* Small Package.

The AD7869 is available in a 24-pin DIP and a 28-pin SOIC package.

* Complete 14-Bit l/O System, Comprising

14-Bit ADC with Track/Hold Amplifier 83 kHz Throughput Rate

14-Bit DAC with Output Amplifier 3.5 ms Settling Time

On-Chip Voltage Reference