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Freescale Semiconductor Advance Information
Document Number: MC33972 Rev. 9.0, 4/2007
Multiple Switch Detection Interface with Suppressed Wake-Up
The 33972 Multiple Switch Detection Interface with Suppressed Wake-Up is designed to detect the closing and opening of up to 22 switch contacts. The switch status, either open or closed, is transferred to the microprocessor unit (MCU) through a serial peripheral interface (SPI). The device also features a 22-to-1 analog multiplexer for reading inputs as analog. The analog input signal is buffered and provided on the AMUX output pin for the MCU to read. The 33972 device has two modes of operation, Normal and Sleep.
MC33972A Datasheet
