microsystems on silicon


Ultra-Low Power PIR Controller with MCU interface


The E931.96 is an ultra-low power PIR motion detector controller IC, ideally suited for wireless motion sensors that make use of a microcontroller (MCU) for managing RF communication.

The parameters of the motion sensing algorithm are programmable though the SERIN input, as a 24 bit serial stream, and stored in RAM on the IC.

Continuous motion sensing signal processing is done with the MCU in sleep mode. Detected motion is signalled through the push-pull output (INT/DOCI). The MCU wake-up with the interrupt from the E931.96 and start executing it’s communication program.

Once the MCU is active, the supply battery voltage and on chip temperature registers can also be read from the IC.

The E931.96 interfaces directly with one or two conventional PIR detectors via a high impedance differential input.

To minimize supply noise on the traditional PIR detector, an integrated low dropout regulator provides the required supply voltage for the sensor.
The integrated circuit is packaged in a cost effective SOIC-8 package.


  • Battery powered and wireless motion sensors
  • PIR motion sensors for security
  • PIR motion sensor lights
  • Occupancy detectors


  • Programmable detection criteria and operating modes
  • On chip supply shunt regulator for conventional PIR detectors
  • Ultra Low power consumption
  • Differential PIR sensor input
  • Excellent power supply rejection
  • Insensitive to RF interference
  • Instantaneous settling after power up