LED driving circuit with stable driving function

Abstract

The invention discloses an LED driving circuit with a stable driving function. The LED driving circuit comprises a load. One end of the load is connected with a drain electrode of a field-effect transistor by an inductor, the other end of the load is connected onto a power source by a resistor R1, the drain electrode of the field-effect transistor is connected onto a positive electrode of a diode, a negative electrode of the diode is connected onto the power source, a common end of the resistor R1 and the load is connected onto an inverting input end of a comparator A1, a non-inverting input end of the comparator A1 is connected onto the power source, an output end of the comparator A1 is connected onto an inverting input end of a comparator A2, a non-inverting input end of the comparator A2 is connected onto a voltage division circuit, an output end of the comparator A2 is connected onto an input end of an AND gate, another input end of the AND gate is grounded, an output end of the AND gate is connected onto a grid electrode of the field-effect transistor, and a source electrode of the field-effect transistor is grounded. The LED driving circuit has the advantages that the LED driving circuit is high in load capacity, average currents can be precisely controlled, accordingly, average values of LED currents can be controlled, and LED lamps can be assuredly stably driven by the LED driving circuit.

Description

technical field [0001] The present invention relates to the field of LED driving circuits, more specifically relates to LED driving circuits with stable driving. Background technique [0002] LED has the advantages of small size, low power, long service life, high brightness, low heat, etc. Moreover, the luminous efficiency of LED lamps has reached and is surpassing that of fluorescent lamps, and it is widely used in the field of general lighting. Under the same working voltage of LED lights, the forward conduction voltage drop of LEDs shows certain differences due to the influence of process discreteness, which affects the stability of LED lights to a certain extent. There are many existing LED driving methods. For example, a hysteresis loop tracking control circuit is used to drive LED lights, and a D flip-flop is used to limit the frequency jitter range. The load capacity of the circuit is not strong and the stability of LED driving is not high. Contents of the inventio...

AI Technical Summary

Problems solved by technology

Under the same working voltage of LED lights, the forward conduction voltage drop of LEDs is different due to the influence of process discreteness, which affects the stability of LED lights to a certain extent.

There are many existing LED driving methods, such as: using a hysteresis loop tracking control circuit to drive LED lights, which uses a D flip-flop to limit the frequency jitter range, the load capacity of the circuit is not strong and the stability of the LED drive is not high

Images