ADS7843E

Overview

The ADS7843E is a 12-bit sampling analog-to-digital converter (ADC) designed specifically for touch screen controller applications. Manufactured by Texas Instruments, this device integrates a 16-channel multiplexer and a sample-and-hold circuit to support four-wire resistive touch screens. It operates on a single 2.7V to 5.25V power supply and features a serial interface compatible with standard SPI, Microwire, and QSPI protocols. The component utilizes a successive approximation register (SAR) architecture and includes an internal reference voltage, eliminating the need for external components in many configurations.

Feature Summary

• 12-bit resolution with 200 kSPS sampling rate
• Integrated 16-channel multiplexer and sample-and-hold
• Internal reference voltage source
• Serial interface compatible with SPI, Microwire, and QSPI

Applications

• Four-wire resistive touch screen controllers
• Portable handheld devices requiring low-power data acquisition
• Industrial control systems with serial communication requirements

Procurement Notes

Verify the specific suffix against the manufacturer's current datasheet to confirm package type and temperature range. The 'E' suffix typically denotes a commercial temperature range and SSOP-16 packaging, but official documentation should be consulted for exact ordering information and RoHS compliance status.

Selection Notes

Select the ADS7843E when a dedicated touch screen controller with integrated multiplexing is required. Ensure the system supports the serial interface timing and that the 12-bit resolution meets the accuracy needs of the application. Consider the internal reference stability if high precision is critical across the full operating temperature range.

Part Context

The ADS7843E belongs to the ADS784x family of touch screen controllers from Texas Instruments. This series is widely used in embedded systems where space and power consumption are constrained. It serves as a specialized solution for converting analog touch coordinates into digital data for microprocessors.

Replacement Considerations

The ADS7843EB is a variant within the same family offering an extended industrial temperature range (-40°C to +85°C). Verify pin compatibility and electrical specifications before substituting.