A Design-for-Sensitivity Strategy for Charge-Pump-Based Receivers

This work presents the theoretical fundamentals of designing charge-pump-based receivers for maximum open-circuit voltage sensitivity (OCVS). From a classical Dickson charge pump with sub-zero-$V_{\mathrm{th}}$ transistors, various models are derived to extract correlation between specific parameters (e.g. number of stages, transistor widths and capacitor sizes) and the output voltage, maximum data rate and input impedance. This approach enabled us to develop an easily applied design strategy for this type of low-power receivers, which we demonstrate here for the 868MHz and 915MHz short-range-devices bands. It also considers an external matching network, our design strategy provides flexibility in layout generation and allows fast designing of receivers. Our strategy focuses on a rapid design flow rather than accurate representation, and is demonstrated using the example of a receiver design. In addition, the limitations of the derivations are discussed, and further optimizations are suggested.