A high output current negative feedback power amplifier amplifies an input signal by use of a monolithic operated amplifier with a current limiting resistor in its output path. The output current of the amplifier is automatically increased when the voltage drop across the current limiting resistor increases...http://www.google.com.au/patents/US6831514?utm_source=gb-gplus-sharePatent US6831514 - Method of increasing output current capability of negative feedback amplifiers with output current limiting and freedom from thermal runaway
