Fully integrated low-power SiGe power amplifier for biomedical applications
A full-integrated very low-power SiGe power amplifier (PA) is realised using the innovations for high performance, 0.25 µm SiGe process. The behaviour of the amplifiers has been optimised for the 2.1–2.4 GHz frequency band for a higher 1 dB compression point and high efficiency at a lower supply voltage. The PA delivers an output power of 3.75 and 1.25 mW for 2 and 1 V, respectively. The PA measurements yielded the following parameters: gain of 13 dB, 1 dB compression point of 5.7 dBm, and power added efficiency of 30% for 2 V supply voltage. The PA circuit can go down to 1 V of supply voltage with a gain of 10 dB, 1 dB compression point of 1 dBm, and power added efficiency of 20%. For both supply voltages, the input and the output of the circuit give good reflection performance. With this performance, the PA circuit may be used for low-power biomedical implanted transceiver systems.