GENERAL DESCRIPTION
The AD7817/AD7818 are 10-bit, single- and 4-channel analog-to-digital converters (ADCs) with an on-chip temperature sensor that can operate from a single 2.7 V to 5.5 V power supply. Each part contains a 9 µs successive approximation converter based around a capacitor digital-to-analog converter (DAC), an on-chip temperature sensor with an accuracy of ±2°C, an on-chip clock oscillator, inherent track-and-hold functionality, and an on-chip reference (2.5 V).
The on-chip temperature sensor of the AD7817/AD7818 can be accessed via Channel 0. When Channel 0 is selected and a conversion is initiated, the resulting ADC code at the end of the conversion gives a measurement of the ambient temperature with a resolution of ±0.25°C. See the Temperature Measurement section.
The AD7817/AD7818 have a flexible serial interface that allows easy interfacing to most microcontrollers. The interface is compatible with the Intel 8051, Motorola SPI and QSPI, and National Semiconductors MICROWIRE protocols. For more information, refer to the AD7817 Serial Interface section and the AD7818 Serial Interface Mode section.
The AD7817 is available in a narrow body, 0.15 inch, 16-lead SOIC and a 16-lead TSSOP, and the AD7818 comes in an 8-lead SOIC and an 8-lead MSOP.

FEATURES
  10-bit ADC with 9 µs conversion time
  1 AD7818 and 4 AD7817 single-ended analog input channels
  On-chip temperature sensor
     Resolution of 0.25°C
     ±2°C error from −40°C to +85°C
     −55°C to +125°C operating range
  Wide operating supply range: 2.7 V to 5.5 V
  Inherent track-and-hold functionality
  On-chip reference (2.5 V ± 1%)
  Overtemperature indicator
  Automatic power-down at the end of a conversion
  Low power operation
     4 µW at a throughput rate of 10 SPS
     40 µW at a throughput rate of 1 kSPS
     400 µW at a throughput rate of 10 kSPS
  Flexible serial interface
 
APPLICATIONS
  Data acquisition systems with ambient temperature
    monitoring
    Industrial process control
    Automotive
    Battery charging applications