LED driving circuit and LED driving controller
AssigneeGreen Solution Technology Co., Ltd.
InventorChung-Che Yu
Life of this patent
Estimating the term…
Abstract
The present invention discloses an LED driving circuit and controller, capable of maintaining an average value of a current flowing through an LED module at a predetermined current value. The LED driving circuit and controller compensates influences of any factors deviating the average value of the current flowing through the LED module by modulating a period of constant on time or constant off time, or by modulating the determining value(s) of current peak value and/or current valley value according to a difference between an actual average value and the preset current value.
Claims9
An LED driving controller, utilized for controlling a switching converter circuit to supply a driving power to an LED module, the LED driving controller comprising:
- a comparator unit, directly receiving a current detecting signal and a reference signal representing a predetermined current value, and generating a comparison result signal according to the reference signal and the current detecting signal representing an amount of a current flowing through the LED module;
- a switch control unit, generating a switch control signal according to the comparison result signal and a predetermined time period to control a switch module of the switching converter circuit;
- and
- a current corrective unit, directly receiving the current detecting signal and the reference signal to determine a difference between the predetermined current value and an average value of the current flowing through the LED module and accordingly generating a current corrective signal to adjust the predetermined time period, thereby stabilize the average value of the current flowing through the LED module at the predetermined current value, wherein the average value of the current flowing through the LED module is determined by integrating the current detecting signal.
An LED driving controller, utilized for controlling a switching converter circuit to supply a driving power to an LED module, the LED driving controller comprising:
- a current corrective unit, directly receiving a current detecting signal and generating at least a reference signal according to the current detecting signal representing an amount of a current flowing through the LED module, wherein the current corrective unit further comprises:
- an error comparator, receiving the current detecting signal and a current reference signal to output a result signal;
- a capacitor, utilized for providing the at least a reference signal;
- a charging unit, coupled to the capacitor and utilized to supply a basic charging current for charging the capacitor;
- and
- a discharge unit, selectively coupled to the capacitor in response to level of the result signal and utilized to supply a discharge current for discharging the capacitor when coupled to the capacitor, the basic charging current is smaller than the discharge current, wherein a level of the reference signal is varied in response to the result signal;
- a comparator unit, directly receiving the current detecting signal and the at least a reference signal and generating a comparison result signal according to the current detecting signal and the least a reference signal;
- and
- a switch control unit, generating a switch control signal in response to the comparison result signal to control a switch module of the switching converter circuit.
Dependencies are inferred from the claim text.