US Patent 7876157 Power amplifier bias circuit having controllable current profile

A power amplifier bias circuit having a controllable current profile includes a first transistor device configured as a switch, and configured to receive a non-regulated system voltage, and a plurality of resistors configured to provide a current and configured to determine an amount of a bias current that flows through a second transistor device, where the second transistor device is part of a current mirror comprising a third transistor device and the amount of bias current flowing through the second transistor device determines a power output of the third transistor device.