Description

A 0.45-V low-power 0.18 ?m CMOS OOK/FSK RF receiver for implantable medical applications is proposed. The re-ceiver utilizes a wake-up mechanism to adjust its power consump-tion automatically by reading the amplitude of the input wirelessOOK/FSK modulated RF signal directly. No additional wireless wake-up commands are required. Such a normally-off and instant-on scheme reduces the power consumption of this receiver sig-nificantly. The power consumption is 129 ?W in sleep mode and 352 ?W in wake-up mode. Other techniques, such as third-order-harmonic cancellation, subharmonic mixing, and forward body biasing are also adopted for better linearity, higher LO-to-RF isolation, and lower VDD, respectively. The measurement results show that the proposed receiver consumes only 2.6 nJ/bit (OOK) and 1 nJ/bit (FSK) to achieve the sensitivities of ? 55 dBm (OOK) and ? 53.5 dBm (FSK) in BER < 10 – 3 constraint. The proposed receiver is designed for low-power and shortdistance MICS band applications.