ADS7846E

Overview

The ADS7846E is a 12-bit resolution resistive touch screen controller manufactured by Texas Instruments. It supports a supply voltage range of 2.2 V to 5.25 V and operates within an industrial temperature range of -40°C to +85°C. The device features a 3-wire serial interface compatible with SPI, QSPI, and MICROWIRE standards, with a sampling rate up to 125 kSPS. It integrates a 2.5 V internal reference voltage source and supports direct battery voltage measurement from 0 V to 6 V. The component is housed in a 16-lead SSOP package.

Feature Summary

• 12-bit resolution with 125 kSPS sampling rate for high-speed touch detection
• Integrated 2.5 V reference voltage source and direct battery measurement capability (0 V to 6 V)
• 3-wire serial interface compatible with standard SPI protocols
• Low power consumption with automatic power-down mode

Applications

• Personal Digital Assistants (PDAs)
• Portable instruments and handheld devices
• Point-of-sale (POS) terminals
• Mobile phones and smartphones
• Touchscreen displays

Procurement Notes

Verify the specific ordering suffix and package variant when sourcing, as the base model number may correspond to different physical packages such as SSOP or TSSOP. Confirm RoHS compliance status and moisture sensitivity level requirements against current manufacturing notices. Check for end-of-life notifications or obsolescence warnings prior to finalizing procurement plans.

Selection Notes

Select this component for designs requiring a single-chip solution for 4-wire resistive touch screens. Ensure the host microcontroller supports the required 3-wire serial interface timing. Verify that the system voltage falls within the 2.2 V to 5.25 V operating range. Consider the integrated 2.5 V reference if external precision references are not available or desired to save board space.

Part Context

The ADS7846E is part of the ADS7846 family, serving as a successor to the ADS7843. It maintains pin compatibility with previous generations while adding features like internal reference and battery monitoring. It is designed specifically for embedded systems requiring accurate touch position and pressure data acquisition.

Replacement Considerations

The ADS7846EG4 is a lead-free version of the same functional device. Other variants in the series include ADS7846N and ADS7846IGQCR, which differ primarily in packaging and temperature grades.