58 VMM2404Application Examples10.7. Connecting Various SensorsThere are many types of sensors that can be connected to the VMM2404, asfollows: Open collector sensors Variable resistance sensors Variable reluctance sensors Switch sensors Voltage sensors CMOS sensors Potentiometer (ratiometric) sensorsNote 1: To optimize the reading accuracy for sensors, dedicate one of themain ground pins (called GND) as a low-current ground return for all sensorson the vehicle.Note 2: When connecting sensors to the VMM2404, use the sensor'sspecification to ensure that the VMM2404 is configured correctly for thesensor.10.7.1. Open CollectorOpen collector sensors are compatible with each type of input on the VMM2404.Open collector sensors are typically used in applications that require digital orfrequency measurements. They work by pulling voltage down to ground or up topower when activated, and are basically a switch that turns on and off.Note: Open collector sensors need a pull-up or pull-down resistor to bias thestate of the sensor when the sensor is not activated. Pull-up and pull-downresistors are internal to the VMM2404.
