AD7843,pdf datasheet (Touch Sc

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