MAX11802EWC+

Overview

The MAX11802EWC+T is a low-power, ultra-small resistive touch-screen controller manufactured by Analog Devices Inc./Maxim Integrated. It operates from a single supply voltage ranging from 1.7V to 3.6V and targets power-sensitive applications such as handheld equipment. The device integrates a 12-bit Successive Approximation Register (SAR) Analog-to-Digital Converter (ADC) and a multiplexer to interface with four-wire resistive touch-screen panels. Communication is handled via a digital serial interface, specifically supporting a 25MHz SPI interface for the MAX11802 variant. The component includes digital preprocessing of touch-screen measurements to reduce bus loading and application-processor resource requirements.

Feature Summary

• 12-Bit SAR ADC with Multiplexer: Provides high-resolution X/Y coordinate and touch pressure measurement capabilities for resistive touch screens.
• Digital Preprocessing: Includes data filtering, noise reduction, and aperture mode for spatial filtering, which reduces bus activity and interrupt generation frequency.
• Low-Power Operation: Consumes 343µW at VDD=1.7V and 34.4ksps, or 888µW at VDD=3.3V and 34.4ksps, featuring auto power-down control.
• Robust ESD Protection: Offers ±4kV HBM protection on general pins and ±8kV HBM protection on X+, X-, Y+, and Y- touch screen pins.

Applications

• Mobile Communication Devices
• PDAs, GPS Receivers, Personal Navigation Devices, and Media Players
• Portable Instruments and POS Terminals
• Handheld Games and Automotive Center Consoles

Procurement Notes

Verify the specific suffix 'T' indicating tape-and-reel packaging when ordering, as the base part number may refer to bulk or other packaging options. Confirm that the MAX11802 variant is selected over the MAX11801/MAX11803 variants, which utilize an I2C interface instead of SPI. Check current availability status, as this product line has been subject to obsolescence notices in recent years.

Selection Notes

Select the MAX11802EWC+T specifically for designs requiring an SPI interface; alternative models in the MAX11800–MAX11803 family use I2C. Ensure the system voltage falls within the 1.7V to 3.6V range. Consider the 12-pin WLP package dimensions (2.14mm x 1.56mm) for space-constrained PCB layouts. Verify compatibility with four-wire resistive touch screens, as this controller does not support capacitive technologies.

Part Context

The MAX11802EWC+T belongs to the MAX11800–MAX11803 family of low-power touch-screen controllers. This family shares core functionalities such as the 12-bit SAR ADC and digital preprocessing features but differs in communication interfaces. The MAX11802 and MAX11800 models feature a 25MHz SPI interface, while the MAX11801 and MAX11803 models offer a 400kHz I2C interface. All variants share similar power consumption profiles and physical package options.

Replacement Considerations

Direct functional substitutes within the same family include the MAX11800EWC+T, which shares the SPI interface and pinout. For I2C-based designs, the MAX11801EWC+T or MAX11803EWC+T are compatible alternatives, though software drivers must be adapted for the different protocol. Cross-family replacements require verification of interface compatibility and package dimensions.