Description

The AD7896 is a fast, 12-bit ADC that operates from a single 2.7 V to 5.5 V supply and is housed in small 8-lead PDIP and 8-lead SOIC packages. The part contains an 8 µs successive approximation ADC, an on-chip track-and-hold amplifier, an on-chip clock, and a high speed serial interface.Output data from the AD7896 is provided via a high speed, serial interface port. This 2-wire serial interface has a serial clock input and a serial data output with the external serial clock accessing the serial data from the part.In addition to the traditional dc accuracy specifications, such as linearity, full-scale, and offset errors, the AD7896 is also specified for dynamic performance parameters, including harmonic distortion and signal-to-noise ratio.The part accepts an analog input range of 0 V to VDD and operates from a single 2.7 V to 5.5 V supply, consuming only 9 mW typical. The VDD input is also used as the reference for the part so that no external reference is required.The AD7896 features a high sampling rate mode and, for low power applications, a proprietary automatic power down mode where the part automatically goes into power down once con-version is complete and 'wakes up' before the next conversion cycle.The part is available in a small, 8-lead, 0.3'' wide, plastic or hermetic dual-in-line package (PDIP) and in an 8-lead, small outline IC (SOIC).PRODUCT HIGHLIGHTS Complete, 12-bit ADC in an 8-Lead Package. The AD7896 contains an 8 µs ADC, a track-and-hold amplifier, control logic, and a high speed serial interface, all in an 8-lead PDIP. The VDD input is used as the reference for the part, so no external reference is needed. This offers considerable space saving over alternative solutions. Low Power, Single-Supply Operation. The AD7896 operates from a single 2.7 V to 5.5 V supply and consumes only 9 mW typical. The automatic powerdown mode, where the part goes into power down once conversion is complete and “wakes up” before the next conversion cycle, makes the AD7896 ideal for battery-powered or portable applications. High Speed Serial Interface. The part provides high speed serial data and serial clock lines allowing for an easy, 2-wire serial interface arrangement.