AD7877 is a touch screen controller manufactured by Analog Devices. It has a 4-wire touch screen interface, LCD noise reduction feature, automatic conversion sequencer and timer, user-programmable conversion parameters, on-chip temperature sensor, on-chip 2.5 V reference, on-chip 8-bit DAC, 3 auxiliary analog inputs, 1 dedicated and 3 optional GPIOs, 2 direct battery measurement channels (0.5 V to 5 V), 3 interrupt outputs, touch-pressure measurement, wake up on touch function, specified throughput rate of 125 kSPS, single supply, VCC of 2.7 V to 5.25 V, separate VDRIVE level for serial interface, shutdown mode: 1 µA max, 32-lead LFCSP 5 mm x 5 mm package.
The AD7877 is a 12-bit successive approximation analog-to-digital converter (ADC) featuring a synchronous serial interface specifically optimized for driving resistive touch screens. It operates from a single power supply ranging from 2.7 V to 5.25 V and supports throughput rates of up to 125 kSPS.
Key features include an on-chip temperature sensor, direct battery measurement channels, an internal 2.5 V reference voltage, and an on-board 8-bit DAC for LCD backlight or contrast control. The device also incorporates noise reduction capabilities via the STOPACQ pin and supports touch-pressure measurement.
| Resolution | 12 Bits |
|---|---|
| Throughput Rate | 125 kSPS |
| Operating Temperature Range | -40°C to +85°C |
| Supply Voltage (Vcc) | 2.7 V to 5.25 V |
| Internal Reference Voltage | 2.5 V |
| Package Type | 32-lead LFCSP |
The device features a 12-bit resolution.
Yes, it includes an on-chip 2.5 V reference.
The specified throughput rate is 125 kSPS.