Modeling of UHF voltage multiplier for radio-triggered wake-up circuits

Wake-up circuits harvest electromagnetic energy emitted by radio devices, and they can be implemented using ultra-high frequency (UHF) voltage multipliers. In this letter, we derive an analytical model of the UHF voltage multiplier. The model is compliant with HSPICE circuit simulations, and it allows for short design time of voltage multipliers for radio-triggered wake-up circuits. According to this model, we design and optimize voltage multipliers with and without junction capacitance matching. With an incident 2.4-GHz signal of less than -30dBm power, the circuits can produce a voltage above 1V within tens of microsecond. This dc output switches an inverter of 200M Omega load and wakes up the rest of the circuits on a wireless node. Copyright (C) 2010 John Wiley & Sons, Ltd.