MC33972APEW

MC33972APEW is a multiple switch detection interface with suppressed wake-up. It 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 analogue multiplexer for reading inputs as analogue. The analogue 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. Normal mode allows programming of the device and supplies switch contacts with pull-up or pull-down current as it monitors switch change of state. The sleep mode provides low quiescent current, which makes the 33972 ideal for automotive and industrial products requiring low sleep-state currents.

• Supply voltage range from 8.0 to 26V (fully operational, VPWR = 13V, TA = 25°C)
• Supply current is 2.0mA typ (all switches open, normal mode, Tri-state disabled, TA = 25°C)
• Interfaces directly to MPU using 3.3V/5.0V SPI protocol
• 8 programmable inputs (switches to battery or ground), 14 switch-to-ground inputs
• Active interrupt (active low INT) on change-of-switch state
• Switch input voltage range from -14 to 38V (VPWR = 13V, TA = 25°C)
• Sleep mode switch scan time range from 100 to 300µs (VPWR = 13V, TA = 25°C)
• Pulse wetting current time range from 15 to 20ms (VPWR = 13V, TA = 25°C)
• Calibrated interrupt timer accuracy is 10% max (VPWR = 13V, TA = 25°C)
• 32 Pins WSOIC-EP package, ambient temperature range from -40 to 125°C