Class AB output stage for an audio power amplifier

摘要

An output stage of an amplifier circuit includes a sinking bipolar circuit 22 for sinking current from an external load 12; a sourcing MOS transistor 14 for sourcing current to the external load 12, a source of the MOS transistor 14 coupled to the sinking bipolar circuit 22 to form a common output node 34; a mirroring MOS transistor 16 having a gate coupled to a gate of the sourcing MOS transistor 14 such that current in the sourcing transistor 14 approximately mirrors current in the mirroring transistor 16; and a current mirror circuit 39 responsive to the mirroring transistor 16 and coupled to control current flow through the sinking bipolar circuit 22.