BVCER - Increased Operating Voltage for SiGe HBTs

SiGe-heterojunction bipolar transistors (HBTs) still sustain their leading RF-application position due to their good noise and HF properties. They also offer a relatively high operating voltage, which is limited by BV_CEO, the emitter collector breakdown voltage with open base. We show that BV_CER, the avalanche breakdown with a resistor RB connected to the base, can be used to define reliable operating conditions exceeding BV_CEO. The measured BV_CER data correlate very well with values calculated from basic transistor parameters and their corresponding multiplication factor data. The functionality of this concept is verified by investigating a power amplifier circuit used at emitter collector voltages exceeding BV _CEO in operational mode enabling significant higher output power