US Patent 9857818 Biasing for lower R

Systems, methods and apparatus for efficient control and biasing of pass devices driven into their triode region of operation are described. The pass devices are arranged in a cascode configuration comprising a plurality of stacked devices. Biasing of the cascode devices can be according to a voltage division scheme which provides a substantially equal voltage division across the stacked devices when the voltage across the stack is high, and provides a skewed voltage division across the stacked devices when voltage across the stack is reduced, while protecting each of the devices from overvoltage and biasing the cascoded devices for a low RON. An exemplary implementation of an LDO controlling the pass devices for providing burst RF power to a power amplifier is described.