GENERAL DESCRIPTION

The AD7450 is a 12-bit, high speed, low power, succes sive-approximation (SAR) analog-to-digital converter featuring a fully differential analog input. It operates from a single 3 V or 5 V power supply and features throughput rates up to 833kSPS or 1MSPS respectively.

This part contains a low-noise, wide bandwidth, differential track and hold amplifier (T/H) which can handle input frequencies in excess of 1MHz with the -3dB point being 20MHz typically. The reference voltage for the AD7450 is applied externally to the VREF pin and can be varied from 100 mV to 2.5 V depending on the power supply and to suit the application. The value of the reference voltage determines the common mode voltage range of the part. With this truly differential input structure and variable reference input, the user can select a variety of input ranges and bias points.

FEATURES

  Fast Throughput Rate: 1MSPS

  Specified for VDD of 3 V and 5 V

  Low Power at max Throughput Rate:

     3 mW typ at 833kSPS with 3 V Supplies

     8 mW typ at 1MSPS with 5 V Supplies

  Fully Differential Analog Input

  Wide Input Bandwidth:

     70dB SINAD at 300kHz Input Frequency

  Flexible Power/Serial Clock Speed Management

  No Pipeline Delays

  High Speed Serial Interface - SPI™/QSPITM/MicroWire™/ DSP Compatible

  Powerdown Mode: 1µA max

  8 Pin µSOIC and SOIC Packages

APPLICATIONS

  Transducer Interface

  Battery Powered Systems

  Data Acquisition Systems

  Portable Instrumentation

  Motor Control

  Communications