Debug and Fault Isolation of an RF/IF Circuit for 3G Cellular Applications With High Leakage: A Case Study

First silicon of a cost effective, BICMOS mixed signal RF/IF integrated circuit (IC) for third generation (3G) cellular phones showed high leakage current on the analog receive supply pins in “battery save” mode. Our tasks were to identify and isolate the source of leakage and to fix the design. Alternate debug techniques were used to isolate the cause of the leakage and provide a solution after inconclusive results were obtained using photon emission microscopy,(1) and infrared microthermography techniques.