A CMOS low-power transceiver with reconfigurable antenna interface for medical implant applications

A low-power transceiver for medical implant communication service is presented. The device consists of three subsystems, which perform wake-up signal reception, data-link binary frequency-shift keying (BFSK) reception, and transmission, respectively. A common antenna interface is reused in the three subsystems, reducing circuit complexity and number of external components. Super-regenerative architecture is used for wake-up reception, and g _m-boosted common-gate stages are used to optimize receiver (RX) performance with low power consumption. The transmitter employs an all-digital frequency-locked loop to directly drive a class AB power amplifier. The transmitter can alternatively use an injection-locked power oscillator for lower bit rates and power consumption. The integrated circuit is designed and fabricated on a 0.18-μm CMOS process. The wake-up RX achieves a - 80-dBm sensitivity for a 50-kb/s signal and a 280-μW dissipation. The BFSK RX achieves a - 97-dBm sensitivity for a 75-kb/s signal and a 2-mW power consumption. Finally, the transmitter achieves an output power of -5 dBm for a power consumption of 2.9 mW.