CAP1203-1-AC3-TR

Overview

The CAP1203-1-AC3-TR is a three-channel capacitive touch sensor controller manufactured by Microchip Technology. It operates on a supply voltage ranging from 3.0V to 5.5V and supports SMBus or I2C communication interfaces with clock frequencies up to 400 kHz. The device features programmable sensitivity, automatic recalibration for parasitic capacitance, and multiple pattern touch recognition. Power consumption varies by state: typical quiescent current is 5 µA in Deep Sleep, 50 µA in Standby with one channel monitored, and approximately 170 µA in Active mode. It includes an active low alert interrupt output and provides 8 kV ESD protection on all pins.

Feature Summary

• Three independent capacitive touch sensor inputs with individual threshold configuration
• Multiple button pattern detection capability generating interrupts upon simultaneous activation
• Low power operation with configurable Active, Standby, and Deep Sleep states
• Integrated analog filtering and digital EMI blockers for noise immunity

Applications

• Desktop and notebook personal computers
• LCD monitors and displays
• Consumer electronics devices
• Home appliances

Procurement Notes

Verify the specific ordering suffix AC3 corresponds to the TDFN package variant when sourcing. Confirm RoHS compliance status directly with the manufacturer documentation prior to integration. Ensure the host system supports the required SMBus or I2C protocol timing specifications for reliable communication.

Selection Notes

Select this component for applications requiring multi-touch gesture recognition or simultaneous button detection. Evaluate the available power states against system energy requirements, particularly if battery operation is necessary. Ensure the host microcontroller can handle the open-drain interrupt signaling and pull-up resistor requirements for the communication bus.

Part Context

This part belongs to the CAP1203 family of capacitive touch controllers designed for general-purpose human-machine interface applications. It serves as a dedicated sensing solution that offloads touch processing tasks from the main system processor, allowing for simplified firmware development and improved system responsiveness.

Replacement Considerations

Consult official Microchip documentation for confirmed substitute part numbers within the same product family. Verify pin compatibility and register mapping before replacing existing components in established designs.

FAQ

How does the CAP1203 handle environmental drift?

The device automatically recalibrates sensor inputs at a programmable rate to compensate for gradual environmental changes such as temperature shifts or humidity variations.

What is the function of the ALERT# pin?

The ALERT# pin serves as an active low interrupt output that signals the host controller when a touch event occurs or when specific conditions, such as calibration failure, are met.

Can the CAP1203 detect multiple buttons pressed at once?

Yes, it includes Multiple Pattern Touch recognition that allows users to define specific sets of buttons to be touched simultaneously, triggering a status bit and interrupt upon detection.