CYTT21403-56LQI44T

Overview

The CYTT21403-56LQI44T is a TrueTouch multi-touch capacitive touchscreen controller featuring a 32-bit ARM Cortex CPU. It supports up to 44 sense I/O pins and reports ten simultaneous touches. The device operates on a digital supply of 1.71–1.95 V or 2.0–5.5 V, with an analog supply of 2.65–4.7 V. Average power consumption is 9 mW, while deep-sleep power is typically 10.7 μW. Communication interfaces include I2C at 100/400 kbps and SPI up to 8 Mbps. It is housed in a 56-pin 6 × 6 × 0.6-mm QFN package.

Feature Summary

• ChargerArmor™ technology providing immunity up to 35-V peak-to-peak (VPP) against charger noise.
• DualSense™ technology for water rejection and wet-finger tracking.
• Supports passive stylus operation down to 2.5 mm with automatic mode switching.
• Glove tracking capability supporting ten fingers with thin gloves (≤1 mm) and two fingers with thick gloves (≤5 mm).

Applications

• Smartphones and mobile devices requiring high touch accuracy.
• Tablets and portable media players with screen sizes up to 7.0 inches.
• White goods and home appliances utilizing capacitive touch interfaces.

Procurement Notes

Verify the specific ordering suffix to confirm package type and tape-and-reel configuration. Confirm that the industrial temperature range meets system requirements. Ensure compatibility with existing firmware drivers, as Android support is explicitly documented. Check for any end-of-life notifications or lifecycle status updates from the manufacturer before finalizing procurement plans.

Selection Notes

Select this component when a balance of low power consumption and robust noise immunity is required. The CYTT21403 variant specifically includes ChargerArmor and DualSense features but lacks Easy Wake functionality found in other models. Choose based on the required number of sense lines; this model supports 44 I/Os. Consider the 56-pin QFN package constraints for PCB layout and thermal management during selection.

Part Context

This part belongs to the Cypress Semiconductor CYTT21X/31X family of TrueTouch controllers. It shares the same physical package and core architecture with variants like the CYTT21401 and CYTT21403, differing primarily in feature sets such as glove tracking and stylus support. The series targets applications needing reliable multi-touch performance in electrically noisy environments.

Replacement Considerations

Direct substitutes within the same family include CYTT21401-56LQI44T and CYTT21100-56LQI44T. Note that these alternatives may lack specific features like ChargerArmor or DualSense. Verify pinout compatibility and register configurations before swapping parts to ensure seamless integration without hardware redesign.

FAQ

What is the maximum number of simultaneous touches supported?

The controller supports reporting up to ten simultaneous finger touches.

Does this component support glove usage?

Yes, it supports ten fingers with thin gloves (≤1 mm thick) and two fingers with thick gloves (≤5 mm thick).

What communication interfaces are available?

It provides an I2C slave interface operating at 100 and 400 kbps, and an SPI slave interface with bit rates up to 8 Mbps.