TWI469688B - A light source supply module with local switch control - Google Patents

Description

Light source supply module with partial switch control

The present invention relates to a lighting device, and more particularly to a light source supply module having local switch control.

With the advancement of optical technology, the process and application of light-emitting diodes (LEDs) are becoming more and more mature, and the light-emitting diodes have small volume, fast response, long life, no attenuation, strong appearance and vibration resistance. It can be full-color illuminating (including invisible light), low loss, low heat radiation, easy mass production, etc. Therefore, more and more light source supply modules are replaced by light-emitting diodes instead of traditional light bulbs.

The traditional dimmer for adjusting the brightness of the bulb is to change the conduction angle of the input power source by the Triode for Alternating Current (TRIAC), so that the average power obtained by the bulb is changed to adjust the brightness. After the three-terminal bidirectional controllable 矽 component is turned on, the input current of the load must be higher than the holding current of the three-terminal bidirectional thyristor element, so that the three-terminal bidirectional steerable 矽 element can be kept turned on to supply the load power. For a conventional light bulb, the current consumed is large, and therefore, the three-terminal bidirectional controllable element can operate normally; however, when the light source supply module with the light emitting diode is dimmed by a conventional dimmer, the light source is supplied. The current consumed by the module is small. Please refer to Figure 1. When the conduction angle is reduced (as shown in waveform 1), the current consumed and the three-terminal bidirectional controllable When the sustain current of the 矽 element is equivalent, the triac can be turned off unexpectedly (as indicated by the dotted line of waveform 1), causing the current output to the illuminating diode to be unintentionally blocked (such as waveform 2). Shown), thus producing a situation in which the light-emitting diodes flicker. Therefore, the design of the light source supply module with the light-emitting diode is still not perfect, and there is still room for improvement.

In view of this, the main object of the present invention is to provide a light source supply module with local switch control, which can avoid the occurrence of flickering of the LED by using a conventional dimmer.

In order to achieve the above object, the present invention provides a light source supply module having a partial switch control, comprising: at least one light emitting diode, a switching power supply device and a control device. The switching power supply device includes an input port, an output port, a power conversion circuit, and a switch circuit, wherein the input port is electrically connected to a dimmer, the dimmer receives a power source, and the power source is changed. a turn-on angle, outputting a dimming power supply to the input port; the output port is electrically connected to the LED; the power conversion circuit includes a rectifying circuit and a DC/DC converter The rectifier circuit is electrically connected to the input port and the DC/DC converter, and the DC/DC converter is electrically connected to the output port, and the rectifier circuit receives the dimming power supply and converts the DC power into DC power and then transmits the DC power. The DC converter is converted into a predetermined voltage or current and outputted; the switch circuit is electrically connected to the DC/DC converter to turn on or block the straight The current outputted by the DC/DC converter limits the current of the DC/DC converter output to the LED to a predetermined current value; the control device is electrically connected to the switch circuit for detecting the rectifier circuit The output DC voltage, when the DC voltage outputted by the rectifier circuit is less than a predetermined value, the control device outputs a control signal to the switch circuit, so that the switch circuit blocks the DC/DC converter output to the LED The current.

According to the above concept, the switching circuit is constructed by means of a Ringing Choke Converter (RCC) circuit.

According to the above concept, the switch circuit includes a first transistor coupled to the second transistor and the first transistor, the switch circuit limiting the first transistor to be electrically connected to the second transistor. The DC/DC converter outputs a current to the load at the predetermined current value.

According to the above concept, the control device is electrically connected to the second transistor, and the control device outputs the control signal to the second transistor to turn on the second transistor and turn off the first transistor to block The DC/DC converter outputs a current to the LED.

According to the above concept, the light source supply module with partial switch control further includes a voltage compensation circuit, and the control device is electrically connected to the switch circuit through the voltage compensation circuit to detect the DC voltage output by the rectifier circuit.

According to the above concept, the light source supply module with partial switch control further includes a voltage dividing circuit, and the control device is electrically connected to the switch circuit through the voltage dividing circuit to detect a DC voltage outputted by the rectifier circuit.

Therefore, the above-mentioned design of the light source supply module with partial switch control can avoid the flashing of the LED when used with a conventional dimmer.

In order that the present invention may be more clearly described, the preferred embodiments are illustrated in the accompanying drawings.

2 is a light source supply module with partial switch control according to a preferred embodiment of the present invention, comprising a switching power supply device 10, a control device 20 and a plurality of light emitting diodes 30. The switching power supply device 10 is electrically connected to a dimmer 50. The dimmer 50 receives a power source 52, and changes the conduction angle of the power source 52, and outputs a dimming power source to the switching power supply device 10. In an embodiment, the power source 52 is an AC power source; the switching power supply device 10 receives and converts the dimming power source to the LEDs 30. The switching power supply device 10 includes an input port 12, an output port 14, a power conversion circuit 16, and a switch circuit 18. The input port 12 is electrically connected to the dimmer 50.

The output port 14 is electrically connected to the LEDs 30.

The power conversion circuit 16 includes a rectifier circuit 161 and a DC/DC converter 162. The rectifier circuit 161 is electrically connected to the input port 12 for receiving the dimming power supply and converting the same. Output after DC. The DC/DC converter 162 is electrically connected to the rectifier circuit 161 and the output port 14 for receiving the output of the rectifier circuit 161. The direct current is generated, and the received electrical energy is converted into electrical energy of a predetermined voltage or current and output to the light emitting diodes 30.

In this embodiment, the switch circuit 18 is formed by a self-exciting (Self-oscillating) circuit of a Ringing Choke Converter (RCC), but not limited thereto, and other feasible Self-excited circuit. The switching circuit 18 is electrically connected to the DC/DC converter 162 for turning on or blocking the power output by the DC/DC converter 162, and limiting the output of the DC/DC converter 162 to the LEDs. The current of 30 is at a predetermined current value, thereby achieving a purpose of supplying a constant current to the light-emitting diodes 30.

The control device 20 is electrically connected to the switch circuit 18 for detecting the DC voltage output by the rectifier circuit 161. When the DC voltage output by the rectifier circuit 161 is less than a predetermined value, the control device 20 outputs a control signal to the The switching circuit causes the switching circuit 18 to block the current output from the DC/DC converter 162 to the LEDs 30.

Please refer to FIG. 3, which is a feasible detailed circuit structure under the structure of the preferred embodiment of the present invention. In this embodiment, the DC/DC converter 162 is an isolated transformer. When the power source 52 starts to supply power to the power conversion circuit 16 via the dimmer 50, the transistor Q1 in the switch circuit 18 is turned on, and the DC/DC converter 162 is activated to supply power to the light-emitting diodes. Body 30, this will cause the collector current of transistor Q1 to rise, and the base voltage of transistor Q2 rises; when the base voltage of transistor Q2 rises to When the value is predetermined, the transistor Q2 is turned on and the transistor Q1 is turned off, and the DC/DC converter 162 starts to release energy, and the voltage of the auxiliary winding N2 of the DC/DC converter 162 is a negative voltage; when the transistor After the Q1 is turned off for a period of time, the DC/DC converter 162 is released, the voltage of the auxiliary winding N2 of the DC/DC converter 162 is turned to a positive voltage, and the transistor Q1 is turned on, and the transistor Q2 is turned off; Through the above principle, the cycles of the transistors Q1 and Q2 are alternately turned on, thereby achieving the effect of limiting the current output from the DC/DC converter 162 to the LEDs 30 to the predetermined current value.

The control device 20 includes a voltage compensation circuit 22 and a controller 24. The controller 24 has an input terminal 24a and an output terminal 24b. The input terminal 24a of the controller 24 is electrically connected to the capacitor C1 of the voltage compensation circuit 22. The output terminal 24b of the controller 24 is electrically connected to The base of the transistor Q2. When the DC voltage outputted by the rectifier circuit 161 changes, the voltage of the capacitor C1 is changed accordingly, whereby the controller 24 can detect the DC voltage value output by the rectifier circuit 161. Referring to FIG. 4, when the controller 24 detects that the voltage of the capacitor C1 is less than a predetermined value (as shown by waveform 1), the controller 24 outputs a high level control signal (as shown by waveform 2). The base of the transistor Q2 is turned on to turn on the transistor Q2 and turn off the transistor Q1, thereby blocking the current output from the DC/DC converter 162 to the LED body 30. In other words, referring to FIG. 5, when the conduction angle of the dimming power supply is reduced (as shown by waveform 1), so that the current flowing into the power conversion circuit 16 is equivalent to the holding current of the dimmer 50, the controller 24 is Output the high level control signal The number (as shown in waveform 2) forcibly blocks the current output from the DC/DC converter 162 to the light-emitting diode 30 (as shown by the waveform 3), so that the light-emitting diodes 30 are in a non-light-emitting state. Thereby, the phenomenon that the light-emitting diodes 30 are flickered when the dimmer 50 is turned off unexpectedly can be avoided.

Further, in addition to the above-described circuit configuration, the control device 40 disclosed in FIG. 6 can also achieve the effects of the above-described control device 20. The control device 40 includes a voltage dividing circuit 42 and a controller 44. The controller 44 is electrically connected to the switch circuit 18 through a voltage dividing circuit 42 formed by a resistor R1 and a resistor R2 for detecting a DC voltage value output by the rectifier circuit 161. Similarly, when the DC voltage value outputted by the rectifier circuit 161 is less than a predetermined value, the controller 44 outputs a high-level control signal to the base of the transistor Q2 to turn on the transistor Q2 and enable the battery. The crystal Q1 is turned off, thereby blocking the current output from the DC/DC converter 162 to the LEDs 30, so as to avoid flickering of the LEDs 30.

It should be noted that the controller 24 and the controller 44 of the foregoing preferred embodiment can be applied to the switching circuit of the electronic chip in addition to the switching circuit 18 of the self-exciting circuit of the oscillating coil converter. The effect of the flashing of the LED. Further, the above description is only for the preferred embodiment of the present invention, and the equivalent structural changes of the present invention and the scope of the patent application are intended to be included in the scope of the present invention.

10‧‧‧Switching power supply unit

12‧‧‧ Input埠

14‧‧‧ Output埠

16‧‧‧Power conversion circuit

161‧‧‧Rectifier circuit

162‧‧‧DC/DC converter

N2‧‧‧Auxiliary coil

18‧‧‧Switch circuit

Q1‧‧‧Optoelectronics

Q2‧‧‧Optoelectronics

20‧‧‧Control device

22‧‧‧Voltage compensation circuit

C1‧‧‧ capacitor

24‧‧‧ Controller

24a‧‧‧ input

24b‧‧‧output

30‧‧‧Lighting diode

40‧‧‧Control device

42‧‧‧voltage circuit

R1‧‧‧ resistance

R2‧‧‧ resistance

44‧‧‧ Controller

50‧‧‧Dimmer

52‧‧‧Power supply

1 is a block diagram of a dimmer turning off a light-emitting diode current at a low conduction angle; FIG. 2 is a block diagram of a preferred embodiment of the present invention; FIG. 3 is a preferred embodiment of the present invention. FIG. 4 is a waveform diagram of a control device output control signal according to a preferred embodiment of the present invention; FIG. 5 is a waveform diagram of a control device for blocking a light-emitting diode current according to a preferred embodiment of the present invention; A preferred circuit diagram of another possible input voltage detection is preferred.

10‧‧‧Switching power supply unit

12‧‧‧ Input埠

14‧‧‧ Output埠

16‧‧‧Power conversion circuit

161‧‧‧Rectifier circuit

162‧‧‧DC/DC converter

18‧‧‧Switch circuit

20‧‧‧Control device

30‧‧‧Lighting diode

50‧‧‧Dimmer

52‧‧‧Power supply

Claims (6)

A light source supply module with partial switch control includes: at least one light emitting diode; a switching power supply device comprising an input port, an output port, a power conversion circuit, and a switch circuit, wherein: the input port is provided a dimmer is electrically connected, the dimmer receives a power source, and changes a conduction angle of the power source, and outputs a dimming power supply to the input port; the output port is electrically connected to the LED; The power conversion circuit includes a rectifier circuit and a DC/DC converter; the rectifier circuit is electrically connected to the input port and the DC/DC converter, and the DC/DC converter is electrically connected to the output port. The rectifier circuit receives the dimming power supply, converts it into direct current power, and converts the power into a predetermined voltage or current through the DC/DC converter, and outputs the power; the switch circuit is electrically connected to the DC/DC converter, To turn on or block the power outputted by the DC/DC converter, and limit the current of the DC/DC converter output to the LED to a predetermined current value; The device is electrically connected to the switch circuit for detecting a DC voltage outputted by the rectifier circuit. When the DC voltage outputted by the rectifier circuit is less than a predetermined value, the control device outputs a control signal to the switch circuit to enable the The switching circuit blocks the current output from the DC/DC converter to the LED. The light source supply module with local switch control according to claim 1, wherein the switch circuit is a Ringing Choke Converter (RCC) The structure of the circuit. The light source supply module of claim 2, wherein the switch circuit comprises a first transistor coupled to the second transistor and coupled to the first transistor, the switch circuit transmitting the first transistor The transistor is in conduction with the second transistor, and limits the current output by the DC/DC converter to the load to the predetermined current value. The light source supply module with local switch control according to claim 3, wherein the control device is electrically connected to the second transistor, and the control device outputs the control signal to the second transistor to turn on the second The crystal turns off the first transistor and blocks the current output from the DC/DC converter to the light emitting diode. The light source supply module with partial switch control according to claim 2 further includes a voltage compensation circuit, and the control device is electrically connected to the switch circuit through the voltage compensation circuit to detect a DC voltage output by the rectifier circuit. The light source supply module with partial switch control according to claim 2 further includes a voltage dividing circuit, wherein the control device is electrically connected to the switch circuit through the voltage dividing circuit to detect a DC voltage output by the rectifier circuit .