The AD7843 is a 12-bit successive approximation ADC with asynchronous serial interface and low on resistance switches fordriving touch screens. The part operates from a single 2.2 V to5.25 V power supply and features throughput rates greater than125 kSPS.The external reference applied to the AD7843 can be variedfrom 1 V to +VCC, while the analog input range is from 0 V toVREF. The device includes a shutdown mode that reduces thecurrent consumption to less than 1 μA.The AD7843 features on-board switches. This, coupled with lowpower and high speed operation, make this device ideal forbattery-powered systems such as personal digital assistants withresistive touch screens, and other portable equipment. The partis available in a 16-lead 0.15" quarter size outline package(QSOP) and a 16-lead thin shrink small outline package(TSSOP).