Infineon/CYPRESS CYAT81688-100AS77

A capacitive touchscreen detects changes in capacitance to determine the location of one or more fingers on the surface of the touchscreen. A typical touchscreen system consists of a capacitive touchscreen sensor, an FPC bonded to the sensor, and the touchscreen controller mounted on the FPC. The FPC connects the touchscreen controller to the host processor. Users can interact with the displayed user interface through finger movements and gestures on the surface of the touchscreen.

CYAT8168X is a capacitive touchscreen controller with the sensing and processing technology to resolve the locations and report the positions of up to ten fingers on the touchscreen. The touchscreen controller converts an array of sensor capacitances into an array of digital values, which are processed by touch-detection and position-resolution algorithms in the controller. These algorithms determine the location and signal magnitude of each finger on the touchscreen.

The CYAT8168X functional block diagram is shown in Figure 2. This device contains a high-performance Arm® 32-bit CPU with an integrated hardware multiply unit. This CPU controls all sensing and processing of measured capacitance results to allow tracking and reporting touches. The controller is optimized for low power and fast response time, with built-in support for manufacturing test. The touchscreen controller communicates with a host through an I²C slave interface at up to 400 kbps or an SPI interface at up to 8 Mbps.

CYAT8168X collects the touchscreen sensor information using the touch subsystem. This touch subsystem consists of a 5-V TX pump, TX drivers, RX channels, and a progra

• Automotive Electronics Council (AEC) AEC-Q100 qualified
• Multitouch capacitive touchscreen controller
  • 32-bit Arm® Cortex® CPU
  • Register-configurable
  • Noise-suppression technologies for display and EMI
• Effective 20-V drive for higher signal-to-noise ratio (SNR)
• AutoArmor improves both electromagnetic emissions and immunity
• External display synchronization
  • Water rejection and wet-finger tracking using DualSense
  • Multitouch glove with automatic mode switching
  • Ten fingers with thin glove (≤ 1-mm thick)
  • Two fingers with thick glove (≤ 5-mm thick)
  • Fingernail tracking
  • Large object rejection
  • Automatic baseline tracking to environmental changes
  • Field upgrades via bootloader
  • Manufacturing Test Kit (MTK)
  • Touchscreen sensor self-test
  • Low power wakeup button (<50 μA)
• System performance (configuration dependent)
  • Screen sizes up to 15-inch diagonal
  • 6.0–mm electrode pitch; 16:10 aspect ratio
  • Up to 88 sense pins, 1836 intersections; 16:10 aspect ratio (34 TX×54 RX)
  • Reports up to ten fingers
  • Small finger support down to 5 mm
  • Refresh rate up to 250 Hz; other rates configurable
  • TX frequency up to 350 kHz
• Power (configuration-dependent)
  • 1.71 V to 1.95 V and 3.0 to 5.5 V logic and digital I/Os supply
  • 3.0 to 5.5 V analog supply
  • 30-mW average power
  • 30-μW typical deep-sleep power
• Sensor and system design (configuration-dependent)
  • Supports a variety of touchscreen sensors and stackups
    • Manhattan, diamond
    • Sensor-on-Lens (SOL)
    • Plastic (PET) and glass-sensor substrates
    • LCD, AMOLED, and IPS displays
    • Metal mesh
• Communication interface
  • I²C slave at 100 kbps and 400 kbps
  • SPI slave bit rates up to 8 Mbps
• Package
  • 100-pin TQFP 14×14×1.4 mm (0.5-mm pitch)
  • 128-pin TQFP 14×20×1.4 mm (0.5-mm pitch)
• Ambient temperature range
  • Automotive-A: -40℃ to 85℃
  • Automotive-S: -40℃ to 105℃