Application of FFT in testing the sensitivity of a typical single-axis integrated circuit Hi-G MEMS accelerometer

MEMS or Microelectro-Mechanical Systems is a technology that integrates electrical and mechanical parts on a common substrate through the use of micro-fabrication techniques. This technology brings into reality a number of wonderful products such as inertial sensors (accelerometers), communications devices (switches) as well as a host of many other applications. Analog Devices’ Micromachined Products Division is the world’s leading manufacturer of inertial MEMS sensors like gyroscopes and accelerometers. Accelerometers have a very important specification known as sensitivity. The sensitivity of an accelerometer defines the output signal of the device as a function of applied acceleration. This parameter is measured during test by shaking the device under test to simulate applied acceleration. The project demonstrates how FFT (Fast Fourier Transform) is being used to test for the sensitivity of a high-g integrated circuit MEMS accelerometer. It also aims to verify the accuracy of the test methodology on the CTS5010 Automated Test Equipment by comparing the measured sensitivity readings against bench sensitivity data measured through a rate table. Finally, the project also shows the potential of using FFT as a troubleshooting tool that would speed up the debug process of test programs and set-ups