Using signal envelope detection for RF MEMS switch testing
Résumé
The test of RF (radiofrequency) integrated circuits at their ever-increasing operating frequency range requires sophisticated test equipment and is time consuming, therefore very expensive. This paper introduces a new method combining low frequency actuation signal as test stimuli and signal envelope detection on the RF output signal to provide a low cost mean for production testing of RF MEMS switches embedded in SiP (System-in-Package) devices. The proposed approach uses the principle of alternate test that replaces conventional specification-based testing procedures. The basic idea is to extract the high frequency characteristics of the switch from the signal envelope of the response. Output parameters like on and off transition time are extracted at low frequency and used in a regression process to predict RF conventional specifications like S-parameters. Preliminary validation results obtained on a capacitive RF switch are presented.