The MAX20091 is a 35-channel automotive contact monitor for automotive applications. Ten contact monitor inputs can be used with either ground- or battery-connected switches; the other 25 inputs are for use with ground-connected switches.

The IC operates over a 5.5V to 28V voltage range and withstands voltages up to 42V. It protects low-voltage circuitry from high voltages and reverse-battery conditions. The IC’s low-current operation under all operating conditions makes it suitable for use in electronic control units (ECUs) that are connected directly to the automotive battery. The IC has an adjustable scan mode that reduces the current drawn in key-off while maintaining polling capability.

The IC features an SPI interface to monitor the switch status and set the device configuration. An interrupt output allows the device to wake a local microcontroller when a switch status change is detected. In addition, a switch status change turns on the internal regulator.

The MAX20091 is available in a compact 48-pin TQFN package and operates over the -40°C to +125°C temperature range.