Opto-isolator with correction circuit

摘要

An opto-isolator with a correction circuit is disclosed. The correction circuit is configured to make adjustments for degradation of the light source of the opto-isolator. The correction circuit may comprise a photodetector for detecting degradation of the light source of the opto-isolator. When the light source degrades below a predetermined level, the correction circuit may be configured to make adjustments.

主权项

1. An opto-isolator for electrical isolation of an electrical input signal from an electrical output signal comprising:
a signal input terminal configured to receive the electrical input signal; an optical emitter coupled to the signal input terminal and configured to generate emitted light in response to the electrical input signal; a first optical receiver comprising a first photodetector arranged proximate to the optical emitter to receive a first portion of the emitted light, wherein the first optical receiver is configured to generate the electrical output signal in response to the emitted light; a signal output terminal coupled to the first optical receiver to receive the electrical output signal; a second optical receiver comprising a second photodetector arranged proximate to the optical emitter to receive a second portion of the emitted light, wherein the second optical receiver is configured to generate a light output electrical signal in response to the second portion of the emitted light, wherein the second optical receiver comprises:
a first reference signal generator configured to generate a first reference signal; anda first comparator coupled with the first reference signal generator and the second photodetector, and configured to generate a first comparison signal in response to the first reference signal and the light output electrical signal; a correction circuitry coupled with the second optical receiver, the correction circuitry configured to make adjustments when the optical emitter degrades; and a threshold correction signal generator coupled with the first comparator and configured to generate a threshold correction signal in response the first comparison signal.