The AD7879W is a low voltage controller for touch screens. It features a 4-wire touch screen interface, qualification for automotive applications, operation from 1.6V to 3.6V, median and averaging filter for noise reduction, automatic conversion sequencer and timer, user-programmable conversion parameters, auxiliary analog input/battery monitor, optional GPIO, interrupt outputs, touch-pressure measurement, touch wake-up function, and shutdown mode.
The AD7879W is a 12-bit successive approximation analog-to-digital converter (SAR ADC) designed to drive 4-wire resistive touch screens. It operates from a single power supply of 1.6 V to 3.6 V and features a throughput rate of up to 105 kSPS. The device includes preprocessing blocks with median and averaging filters to reduce noise from LCDs and other sources, as well as temperature and touch-pressure measurement capabilities.
The AD7879W supports both SPI and I2C-compatible interfaces (the latter for the AD7879-1W variant) and can function in slave or standalone master mode. It features a shutdown mode that reduces current consumption to less than 6 µA, making it suitable for battery-powered applications such as automotive systems, PDAs, and mobile phones.
| Resolution | 12 Bits |
|---|---|
| Throughput Rate | 105 kSPS |
| Shutdown Mode Current | < 6 µA |
| Operating Temperature Range | -40°C to +85°C |
The device works with a single power supply ranging from 1.6 V to 3.6 V.
The standard AD7879W supports SPI, while the AD7879-1W variant offers an I2C-compatible interface.
The device is available in a 16-lead TSSOP and a 16-lead LFCSP.