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.

特性 Features

? Designed to operate 5.5 V ≤ VPWR ≤ 26 V

? Switch input voltage range -14 V to VPWR, 40 V Max

? Interfaces directly to MPU using 3.3 V/5.0 V SPI protocol

? Selectable wake-up on change of state

? Selectable wetting current (16 or 2.0 mA)

? 8 programmable inputs (switches to battery or ground)

? 14 switch-to-ground inputs

? Typical standby current - VPWR = 100 μA and VDD = 20 μA

? Active interrupt (INT) on change-of-switch state

? Pb-free packaging designated by suffix code EW

? Exposed pad packaging designated by suffix code EK