Cypress Semiconductor has introduced the TrueTouch CYTT21X/31X capacitive touchscreen controller family, which is intended to enable smartphones, e-readers, and low-cost tablets to offer several advanced features. The CYTT31X supports input from a passive stylus with a tip as thin as 2.5 mm, which is essential for writing in languages that require enhanced character recognition for reliable text input (e.g., Chinese, Korean and Japanese). The CYTT21X controller supports a face detection feature that prevents unintended touches from accidentally hanging up a call. This feature eliminates the need for IR proximity sensors by using the touchscreen sensor to detect a face 25-mm away.
The CYTT21X/31X controllers enable ultra-thin form factors by leveraging Cypress’s Single-Layer Independent Multi-touch (SLIM) sensor structures. The controllers provide best-in-class accuracy and linearity for fingers of different sizes and gloves of various materials and thicknesses up to 5 mm, including ski gloves. In addition, they automatically switch between glove, stylus, and finger tracking without requiring you to switch settings. The family offers water rejection and wet finger tracking with immunity to electronic noise generated by aftermarket chargers and displays. The CYTT21X/31X controllers include up to 48 I/Os with an I2C interface and up to 44 I/Os with an I2C and SPI.
The CYTT21X/31X controllers deliver robust immunity to charger noise of up to 35 VPP. The controllers are based on a 32-bit ARM Cortex M-Core processor that is known for high-efficiency MIPS/mW. With Cypress’s DualSense technology to execute both self-capacitance and mutual-capacitance measurements in the same device, TrueTouch solutions offer water rejection and wet finger tracking for seamless performance in real-world conditions, including the presence of rain, condensation, or sweat.
The TrueTouch CYTT21X/31X controllers are currently sampling, with production expected in the second quarter of 2015. The controllers are available in mobile-friendly 44-pin, 48-pin and 56-pin QFN packages.
Source: Cypress Semiconductor
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