Title :
A monolithic power op amp
Author :
Widlar, Robert J. ; Yamatake, Mineo
fDate :
4/1/1988 12:00:00 AM
Abstract :
The standard junction-isolated power process has been modified by the addition of polycrystalline-film resistors to solve the topological problems encountered in making 90-W, 80-V, 10-A power transistors and connecting them together for a push-pull output. An all n-p-n output stage that holds crossover distortion to 0.01% while driving a 4-Ω load, even with the quiescent current below 20 mA, has been developed. It is stable with all reactive loads and does not have the spurious-oscillation problems observed with the familiar quasicomplementary amplifier. These innovations are described along with the design of a complete power op amp, the LM12. The prevention of failures from substrate currents which occur when the output is driven outside the supply by inductive loads is discussed
Keywords :
bipolar integrated circuits; electric distortion; integrated circuit technology; operational amplifiers; power amplifiers; power integrated circuits; 10 A; 20 mA; 4 ohm; 80 V; 90 W; LM12; all n-p-n output stage; crossover distortion; innovations; junction-isolated power process; monolithic power op amp; polycrystalline-film resistors; power transistors; push-pull output; quiescent current; reactive loads; stable with inductive loads; substrate currents; topological problems; Joining processes; Operational amplifiers; Packaging machines; Power amplifiers; Power transistors; Protection; Regulators; Resistors; Technological innovation; Voltage;
Journal_Title :
Solid-State Circuits, IEEE Journal of
