PCA9704PW/Q900J is a low power 18V tolerant SPI general purpose input (GPI) with maskable (active low) INT shift register designed to monitor the status of switch inputs. It generates an interrupt when one or more of the switch inputs change state but allows selected inputs to not generate interrupts using the interrupt masking feature. The input level is recognized as a HIGH when it is greater than 0.8 x VDD and as a LOW when it is less than 0.55 x VDD (minimum LOW threshold of 2.5V at 5V node). The PCA9704 can monitor up to 8 switch inputs. The falling edge of the CS pin samples the input port status and clears the interrupt. When CS is LOW, the rising edge of the SCLK loads the shift register and shifts the value out of the shift register. Application includes automotive, body control modules, electronic control units (for example, for body controller), switch monitoring, SBC wake pin extension, industrial equipment, cellular telephones, emergency lighting.