The AD7817 / AD7818 is a 10-bit single-channel and 4-channel analog-to-digital converter (adc) with on-chip temperature sensors that operate from a single 2.7V to 5.5V power supply. Each device contains a 9μs sequential approximation converter based on a capacitive digital-to-analog converter (DAC), an on-chip temperature sensor with an accuracy of ±2°C, an on-chip clock oscillator, inherent track-hold functionality, and an on-chip reference (2.5V).
AD7817 Functional Block Diagram
AD7818 Functional Block Diagram
The on-chip temperature sensor for the AD7817 / AD7818 can be accessed through channel 0. When channel 0 is selected and the conversion begins, the adc code generated at the end of the conversion gives a measurement of the ambient temperature at a resolution of ±0.25°C, refer to the Temperature Measurement section. The AD7817 / AD7818 has a flexible serial interface for easy connection to most microcontrollers.
The interface is compatible with Intel 8051, MOTOROLA SPI and QSPI, and the National Semiconductor Conductive Tape Protocol. The AD7817 has a narrow-body, 0.15-inch, 16-pin SOIC and 16-pin TSSOP, and the AD7818 has an 8-pin SOIC and 8-pin MSOP.
