STMicroelectronics STMPE821
The STMPE821 is a GPIO (general purpose input/output) port expander able to interface a main digital ASIC via the two-line bidirectional bus (I2C). The STMPE821 offers great flexibility, as each I/O can be configured as input, output or specific functions. The device has been designed with very low quiescent current and includes a wakeup feature for each I/O, to optimize the power consumption of the device.FEATURES
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● to 8 GPIOs to 8 touchkey capacitive touch inputs Operating voltage 1.8 - 5.5 V Internal regulator Interrupt output pin I2C interface 8 kV HBM ESD protection 40 fF resolution, 128 steps capacitance measurement (5.0 pF dynamic range) Advanced data filtering (AFS) Environment tracking calibration (ETC) Individually adjustable touch variance (TVR) setting for all channels Adjustable environmental variance (EVR) for optimal calibration QFN16L (2.6 x 1.8 mm)
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DESCRIPTION
A separate GPIO expander is often used in mobile multimedia platforms to solve the problems of the limited amount of GPIOs typically available on the digital engine. Mobile and smart phones Portable media players Game consoles Table 1. Device summary Order code STMPE821QTR Package QFN16L (2.6 x 1.8 mm) Packing Tape and reel June 2008 Rev 2 1/55 55 This is preliminary information on a new product now in development or undergoing evaluation. Details are subject to change without notice.