A RF Amplifier with Oscillation-Based BIST Based on Differential Power Detection

Oscillation-based built-in self-testing (OBIST) enables self-testing of active circuits without the application of a test vector. It is shown that the output f
₀
and P
_osc
of a microwave amplifier under OBIST varies under supply rail variation (which causes variation in P1db and mid-band gain). It is shown that both parameters can be detected by differential power detection, but that the approach lends itself better to P
_osc
-based detection than /o-based detection. Two distinct oscillation modes are identified, which may be exploited for future built-in self-diagnosis and self-healing.