LED, testing method and article

摘要

A Light Emitting Diode (LED) driving circuit includes a reference-voltage terminal, an input terminal to receive a pulse-width modulated (PWM) power signal, and a PWM output terminal. An LED is coupled across the PWM output terminal and the reference-voltage terminal. A measurement capacitor circuit and a voltage-divider network are coupled in parallel with the LED. During an interruption of the PWM power signal, a sense node of the voltage-divider provides a voltage indicative of a temperature of the LED prior to the interruption. The voltage indicative of the temperature is used to control driving of the LED.

主权项

1. A Light Emitting Diode (LED) driving circuit, comprising:
a reference-voltage terminal; an input terminal configured to receive a pulse-width modulated (PWM) power signal; a PWM output terminal, wherein the PWM output terminal and the reference-voltage terminal are configured, in operation, to provide the PWM power signal to one or more LEDs; a measurement capacitor circuit coupled between the PWM output terminal and the reference-voltage terminal; a voltage-divider network coupled between the PWM output terminal and the reference-voltage terminal; and a sensed-voltage output terminal coupled to an intermediate node of the voltage divider network, and configured, in operation, to provide a voltage signal during an interruption of the PWM power signal which is indicative of a junction temperature of the one or more LEDs prior to the interruption of the PWM power signal.