LED DRIVING DEVICE, LED LIGHTING APPARATUS, AND ERROR AMPLIFICATION CIRCUIT

摘要

An error amplification circuit amplifies an error voltage between a reference voltage and an output voltage of the LED current sensor. A control circuit controls the DC output power so that the DC output power becomes a predetermined value, by performing on-off control on a switching element based on the output voltage of the error amplification circuit. The error amplification circuit includes an error amplifier, a phase compensation circuit connected between an inverting input terminal and an output terminal of the error amplifier and having a serial circuit of a phase compensation capacitor and a phase compensation resistor, a gain adjustment resistor serially connected at one end to the serial circuit and connected at the other end to the LED current sensor, and a short circuit configured to make the inverting input terminal of the error amplifier grounded for a predetermined period of time after activation.

主权项

1. An LED driving device that transforms AC input power into desired DC output power and supplies the DC output power to an LED load, the LED driving device comprising:
a switching element configured to be subjected to on-off control; an LED current sensor serially connected to the LED load and configured to detect a current flowing through the LED load; an error amplification circuit configured to amplify an error voltage between a reference voltage and a voltage which is based on the current detected by the LED current sensor; and a control circuit configured to control the DC output power so that the DC output power becomes a predetermined value, by performing the on-off control on the switching element based on the error voltage amplified by the error amplification circuit, wherein the error amplification circuit includes
an error amplifier,a phase compensation circuit being connected between an inverting input terminal and an output terminal of the error amplifier and having a serial circuit of a phase compensation capacitor and a phase compensation resistor,a gain adjustment resistor serially connected at one end to the serial circuit and connected at the other end to the LED current sensor, anda short circuit configured to make the inverting input terminal of the error amplifier grounded for a predetermined period of time after activation.