Overview
The AD7873ACPZ is a 12-bit successive approximation analog-to-digital converter (ADC) designed by Analog Devices Inc. This component is specifically tailored for touch screen applications, offering a 4-wire resistive touch screen interface. It operates from a single supply voltage ranging from 2.2 V to 5.25 V and features a throughput rate of 125 kSPS. The device includes on-chip track-and-hold, multiplexer, ADC, reference, temperature sensor, and serial interface, making it a comprehensive solution for various touch screen-based devices.
Key Specifications
| Parameter | Value | Unit | Comments |
|---|---|---|---|
| Number of Bits | 12 | ||
| Sampling Rate | 125 kSPS | Maximum throughput rate | |
| Polarity | Unipolar | ||
| Interface | Serial (SPI compatible) | ||
| Integral Nonlinearity (INL) | 2 LSB | ||
| Package | 16-VQFN Exposed Pad, CSP | ||
| Supply Voltage | 2.2 V to 5.25 V | V | Functional range |
| On-chip Reference | 2.5 V | V | Available for external use if buffered |
| Shutdown Current | 1 µA (maximum) | µA | In shutdown mode |
Key Features
- 4-wire resistive touch screen interface
- On-chip temperature sensor with a range of −40°C to +85°C
- On-chip 2.5 V reference voltage
- Low on-resistance switches for driving touch screens
- Direct battery measurement and touch pressure measurement capabilities
- Auxiliary analog input and shutdown mode for power conservation
- Serial clock input (DCLK) for data access and ADC clock source
- Available in 16-lead QSOP, TSSOP, and LFCSP packages
Applications
- Personal digital assistants
- Smart hand-held devices
- Touch screen monitors
- Point-of-sale terminals
- Pagers
Q & A
- What is the AD7873ACPZ used for?
The AD7873ACPZ is used as a touch screen controller, particularly for 4-wire resistive touch screens. - What is the resolution of the AD7873ACPZ?
The AD7873ACPZ has a 12-bit resolution. - What is the maximum sampling rate of the AD7873ACPZ?
The maximum sampling rate is 125 kSPS. - What type of interface does the AD7873ACPZ use?
The AD7873ACPZ uses a serial interface, compatible with SPI. - What is the supply voltage range for the AD7873ACPZ?
The supply voltage range is from 2.2 V to 5.25 V. - Does the AD7873ACPZ have an on-chip reference voltage?
Yes, it has an on-chip 2.5 V reference voltage. - What is the shutdown current of the AD7873ACPZ?
The shutdown current is less than 1 µA. - In what packages is the AD7873ACPZ available?
The AD7873ACPZ is available in 16-lead QSOP, TSSOP, and LFCSP packages. - What additional measurements can the AD7873ACPZ perform?
The AD7873ACPZ can perform direct battery measurement, temperature measurement, and touch pressure measurement. - Is the AD7873ACPZ RoHS compliant?
Yes, the AD7873ACPZ is RoHS compliant and lead-free.
