AD7823,pdf,datasheet (2.7 V to 5.5 V, 4.5 ms, 8-Bit ADC in 8)

　　The AD7823 is a high speed, low power, 8-bit A/D converter that operates from a single 2.7 V to 5.5 V supply. The part contains a 4.5 µs successive approximation A/D converter, inherent track-and-hold functionality (with a pseudo differential input) and a high speed serial interface that interfaces to most microcontrollers. AD7823 is fully specified over a temperature range of -40°C to +125°C.
By using a technique that samples the state of the CONVST (convert start) signal at the end of a conversion, the AD7823 may be used in an automatic power-down mode. When used in this mode, the AD7823 powers down automatically at the end of a conversion and "wakes up" at the start of a new conversion. This feature significantly reduces the power consumption of the part at lower throughput rates. The AD7823 can also operate in a high speed mode where the part is not powered down between conversions. In this high speed mode of operation, the conversion time of the AD7823 is 4.5 µs. The maximum throughput rate is dependent on the speed of the serial interface of the microcontroller.
The part is available in a small, 8-pin 0.3" wide, plastic dual-in-line package (mini-DIP); in an 8-lead, small outline IC (SOIC); and in an 8-lead microSOIC package.