US Patent 11569812 RF switch stack with charge control elements

Methods and devices to address the undesired DC voltage distribution across switch stacks in OFF state are disclosed. The disclosed devices include charge control elements that sample the RF signal to generate superimposed voltages at specific points of the switch stack biasing circuit. The provided voltages help reducing the drooping voltages on drain/source/body terminals of the transistors within the stack by supplying the current drawn by drain/source terminals of the stacked transistors and/or by sinking the body leakage current exiting the body terminals of such transistors. Methods and techniques teaching how to provide proper tapping points in the biasing circuit to sample the RF signal are also disclosed.