34978 Overview
NXP Semiconductors Technical Data 22 channel multiple switch detection interface with programmable wetting current Document Number: 8.0, 7/2018 33978 34978 The 33978 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).
34978 Key Features
- Fully functional operation 4.5 V ≤ VBATP ≤ 36 V
- Full parametric operation 6.0 V ≤ VBATP ≤ 28 V
- Operating switch input voltage range from -1.0 V to 36 V
- Eight programmable inputs (switches to battery or ground)
- 14 switch-to-ground inputs
- Interfaces directly to an MCU using 3.3 V / 5.0 V SPI protocol
- Selectable wake-up on change of state
- Typical standby current IBATP = 30 μA and IDDQ = 10 μA
- Active interrupt (INT_B) on change-of-switch state
- Integrated battery and temperature sensing