Abstract: A drive transistor has its base coupled to a circuit input and its collector coupled to provide an output current at a circuit output. The output current is responsive to a base current received at the base of the drive transistor. A voltage induced across a resistor connected between the circuit input and the base of the drive transistor indicates the amount of drive transistor base current. A portion of an input current presented at the circuit input is diverted to the circuit output based on the indicated amount of drive transistor base current. The remaining portion of the input current is provided as the drive transistor base current. The drive transistor is thus prevented from saturating.