A 480-µW Ultra-Low-Power OOK Transmitter with 24-Phase Passive Polyphase Filter Achieving 12× Frequency Multiplication at 25Mbps for Biomedical Application

A high frequency multiplication 407-425 MHz ultra-low-power (ULP) OOK wireless transmitter (TX) is presented, which uses 24-phase Passive Polyphase Filter (PPF) and Fast-Switched Edge Combiner Power Amplifier (FS-ECPA). This is the first TX with 24-phase PPF using pole splitting technique to generate robust multiphase signals for 12× frequency multiplication. It also can reduce the overall power consumption of the TX, as the circuit before FS-ECPA operates at the extreme low frequencies. To increase the modulated data rate, a FS-ECPA is proposed to fast switching the on/off states. The TX is designed in 55nm CMOS process with 480µW power consumption under 1V supply voltage, and the active area is 0.23 mm². The post-layout simulated output power is -9.7dBm with 25Mbps OOK data rate. The TX also achieves a global efficiency of 22.6% and a figure-of-merit (FoM) of 0.18 nJ/(bit*mW) respectively.