GENERAL DESCRIPTION
The AD7879 is a 12-bit successive approximation analog-todigital converter (ADC) with a synchronous serial interface and low on-resistance switches for driving 4-wire resistive touch screens. The AD7879 works with a very low power supply (a single 1.6 V to 3.6 V) and features throughput rates of 105 kSPS. The device includes a shutdown mode that reduces its current consumption to less than 6 μA.

FEATURES
    4-wire touch screen interface
    1.6 V to 3.6 V operation
    Median and averaging filter to reduce noise
    Automatic conversion sequencer and timer
    User-programmable conversion parameters
    Auxiliary analog input/battery monitor (0.5 V to 5 V)
    1 optional GPIO
    Interrupt outputs (INT, PENIRQ)
    Touch-pressure measurement
    Wake-up on touch function
    Shutdown mode: 6 μA maximum
    12-ball, 1.6 mm × 2 mm WLCSP
    16-lead, 4 mm × 4 mm LFCSP

APPLICATIONS
    Personal digital assistants
    Smart hand-held devices
    Touch screen monitors
    Point-of-sale terminals
    Medical devices
    Cell phones