CN201887984U - Constant-current switch power source capable of driving multiple LED lamps - Google Patents

Abstract

The utility model discloses a constant-current switch power source capable of driving multiple LED lamps, which comprises a power input interface, a rectifying filter circuit, a primary DC/DC conversion circuit, a first direct-current voltage output circuit, a second direct-current voltage output circuit and secondary DC/DC conversion loops. The power input interface, the rectifying filter circuit and the primary DC/DC conversion circuit are sequentially connected, the primary DC/DC conversion circuit is connected with the first direct-current voltage output circuit and the second direct-current voltage output circuit which are connected in parallel, the first direct-current voltage output circuit is connected with an LED lamp group, the second direct-current voltage output circuit is connected with at least one group of secondary DC/DC conversion loops, the groups of secondary DC/DC conversion loops are connected in parallel, and each secondary DC/DC conversion loop is connected with an LED lamp group. The constant-current switch power can solve the problems that when a plurality of LED lamp groups are connected in parallel, current is unequal, and illumination is uneven, and when the number of LED lamps in serial connection in each LED lamp group is less, efficiency is low, heating is severe, and all lamps are extinguished when an individual LED lamp is damaged.

Description

Drive the constant current switch power supply of LED multi-path lamp

Technical field

The utility model relates to a kind of Switching Power Supply, more particularly relates to a kind of Switching Power Supply that drives the constant current of LED multi-path lamp.

Background technology

Scheme commonly used at present mainly contains following 4 kinds:

(1) luminous even for guaranteeing, all LED lamps series connection are used, as long as there is a LED lamp to damage like this, all LED lamps will all extinguish, and bring extinction to illumination.And the LED lamp of series connection is too much, and output voltage is too high, and security performance is variation thereupon also.

(2) damage the problem that all LED lamps of causing all extinguish for solving indivedual LED lamps, require the user to use the extraordinary LED lamp series connection of consistency after, in parallel again the use.Even the consistency of LED lamp is very good, but the radiating condition of each LED lamp there are differences, and can cause temperature inconsistent, difference along with temperature, individual difference can slowly show, and it is inconsistent that the electric current in each loop will become, luminous and the heating all inconsistent.And luminous and heating is inconsistent, it is uneven further to cause electric current to distribute again, cause luminous serious inhomogeneous and indivedual loops because of the excessive LED of the burning lamp of electric current, after the LED in certain loop lamp is burnt, this loop is current sinking no longer, and the electric current of distributing to this loop originally can be assigned in other loops, causes other loop currents excessive, from and burn other paths of LEDs lamps, finally cause whole LED lamps to damage.

(3) directly be constant pressure source output, regulate the electric current of LED lamp by series limiting resistor.A big chunk energy consumption is arranged like this on current-limiting resistance, so not only greatly reduce efficient, and the energy that consumes in resistance all will be with the form of heat, be diffused into power supply and LED lamp around, further worsen environment for use, the life-span of whole power supply and LED lamp is shortened greatly.

(4) earlier electric main is converted to a fixing direct voltage, or directly uses direct voltage.And then by secondary DC/DC conversion, conversion goes out the output that the constant current of multichannel band detects.Like this, the LED lamp number in each loop is more, and during near fixing direct voltage, secondary DC/DC conversion loss is little, and efficient can be too not low; Less when the LED in each loop lamp number, it is very big that secondary DC/DC conversion loss will become, and efficient will reduce greatly.The energy of loss all with the form of heat be diffused into power supply and LED lamp around, have a strong impact on life-span of power supply and LED lamp.

Summary of the invention

In order to address the above problem, the utility model provides a kind of Switching Power Supply that drives the constant current of LED multi-path lamp, the series connection number that has solved many groups LED lamp not current-sharing of parallel connection and every paths of LEDs lamp more after a little while, the problem that efficient is low, heating is serious, when also having solved certain indivedual LED lamp simultaneously and having damaged, the problem that all LED lamps all extinguish has improved the reliability of complete machine, also makes the application of LED lamp further widen.

The utility model specifically is achieved through the following technical solutions:

A kind of constant current switch power supply that drives the LED multi-path lamp, it comprises power input interface, current rectifying and wave filtering circuit, DC/DC conversion primary side circuit, first group of dc voltage circuit of output, second group of dc voltage circuit of output and secondary DC/DC transformation loop, described power input interface, current rectifying and wave filtering circuit, DC/DC conversion primary side circuit connect successively, described DC/DC conversion primary side circuit connects first group of dc voltage circuit of output in parallel and second group of dc voltage circuit of output, and first group of dc voltage circuit of described output connects one group of LED lamp; Second group of dc voltage circuit of described output connects at least one group of secondary DC/DC transformation loop that is connected in parallel, and described secondary DC/DC transformation loop connects one group of LED lamp respectively.

Described DC/DC conversion primary side circuit comprises pwm generator, power device, high frequency transformer primary side, sampling feedback receiving loop, to carry out switch change-over near level and smooth direct voltage, and the signal that can receive according to feedback, adjust pulsewidth or arteries and veins automatically frequently;

First group of dc voltage circuit of described output comprises current sample ring and voltage sample ring, described current sample ring can be controlled output current, output voltage during operate as normal is by the LED number and the characteristic decision of series connection, and described voltage sample ring regulating loop opens circuit or the output voltage when not connecing the LED lamp;

Described secondary DC/DC transformation loop comprises the current sample ring;

The output voltage of second group of dc voltage circuit of described output is greater than the output voltage of first group of dc voltage circuit of output.

The beneficial effects of the utility model are: can solve not current-sharing when organizing the parallel connection of LED lamps more, every group of LED lamp series connection number is efficient problem low, that all lamps extinguished when the serious or indivedual LED lamps of heating damaged after a little while, and its loss is little, efficient is high, the good reliability of complete machine.

Description of drawings

Fig. 1 is a structural principle schematic diagram of the present utility model.

Embodiment

Be illustrated in figure 1 as the structural principle schematic diagram of utility model, a kind of constant current switch power supply that drives the LED multi-path lamp, it comprises power input interface 1, current rectifying andwave filtering circuit 2, DC/DC conversionprimary side circuit 3, export first group ofdc voltage circuit 4, export second group ofdc voltage circuit 5, secondary DC/DC transformation loop 6 andLED lamp 7, described power input interface 1, current rectifying andwave filtering circuit 2, DC/DC conversionprimary side circuit 3 connects successively, described DC/DC conversionprimary side circuit 3 connects first group of dc voltage circuit of output in parallel 4 and second group ofdc voltage circuit 5 of output, and first group of dc voltage circuit of describedoutput 4 connects one group ofLED lamp 7; Second group of dc voltage circuit of describedoutput 5 connects at least one group of secondary DC/DC transformation loop 6 that is connected in parallel, and described every group of secondary DC/DC transformation loop 6 connects one group ofLED lamp 7 respectively.

Current rectifying andwave filtering circuit 2 at first will be mixed in the noise of frequency clock, carry out filtration treatment as thunderbolt surge, burst of pulses, and the noise that stops power supply to produce simultaneously feeds back in the electrical network, carry out rectification then, filtering converts thereof near level and smooth direct voltage.

Described DC/DC conversionprimary side circuit 3 comprises pwm generator, power device, high frequency transformer primary side, sampling feedback receiving loop, can will carry out switch change-over near level and smooth direct voltage, and the signal that can receive according to feedback, adjust pulsewidth automatically.Because it has adopted high-frequency convertor technology, has dwindled the volume of whole power supply greatly, has also improved the efficient of complete machine.

Export first group ofdc voltage circuit 4 and comprise current sample ring and voltage sample ring, the LED number decision that the output current of described current sample ring is connected during according to operate as normal, the energy that so just can guarantee power supply output is all supplied with the LED lamp, does not have extra loss; Described voltage sample ring regulating loop opens circuit or the output voltage during short circuit, and when occurring power supply like this and entering standby, protection or distress condition, power supply also can be worked, and guarantees the normal operation in other loops.

Described secondary DC/DC transformation loop 6 comprises the current sample ring, no matter individual difference or temperature drift so all can not influence the electric current by the LED lamp, guarantees that power supply can be by the electric current operation of setting.

Utility model is converted to two groups of different direct voltages with electric main through rectifying and wave-filtering, DC/DC conversion earlier, and magnitude of voltage is unfixing.First group of dc voltage value is subjected to 2 closed loops, current sample ring, the control of voltage sample ring.During normal the use,, so just can guarantee that the energy of power supply output is all supplied with the LED lamp, not have excess loss by current sample ring (according to the number and the characteristic of series LED lamp) decision; When this loop had the LED lamp to damage or do not connect the LED lamp, output voltage just the phenomenon that power supply enters holding state, guard mode or damage can not occur by the decision of voltage sample ring.Power supply still can operate as normal, to guarantee the LED lamp operate as normal in other loop.No matter how every group of LED lamp number of connecting changes, and second group of direct voltage is on the basis of first group of direct voltage, and several volts that superpose again (by transformer induction, rectification) obtain.Remake secondary DC/DC conversion then, conversion goes out the output that detects with constant current.Like this, no matter how the number of series LED lamp changes, and the input of secondary DC/DC conversion is all little with output pressure reduction, so loss is little, efficient is higher.Therefore, promote the efficient of complete machine and the reliability of complete machine greatly, also made the application of LED lamp further widen simultaneously.

Claims (5)

1. constant current switch power supply that drives the LED multi-path lamp, it is characterized in that, it comprises power input interface, current rectifying and wave filtering circuit, DC/DC conversion primary side circuit, export first group of dc voltage circuit, export second group of dc voltage circuit and secondary DC/DC transformation loop, described power input interface, current rectifying and wave filtering circuit, DC/DC conversion primary side circuit connects successively, described DC/DC conversion primary side circuit connects first group of dc voltage circuit of output in parallel and second group of dc voltage circuit of output, and first group of dc voltage circuit of described output connects one group of LED lamp; Second group of dc voltage circuit of described output connects at least one group of secondary DC/DC transformation loop that is connected in parallel, and described secondary DC/DC transformation loop connects one group of LED lamp respectively.

2. the constant current switch power supply of driving LED multi-path lamp as claimed in claim 1, it is characterized in that, described DC/DC conversion primary side circuit comprises pwm generator, power device, high frequency transformer primary side, sampling feedback receiving loop, to carry out switch change-over near level and smooth direct voltage, and the signal that can receive according to feedback, adjust pulsewidth or arteries and veins automatically frequently.

3. the constant current switch power supply of driving LED multi-path lamp as claimed in claim 1, it is characterized in that, first group of dc voltage circuit of described output comprises current sample ring and voltage sample ring, described current sample ring can be controlled output current, output voltage during operate as normal is by the LED number and the characteristic decision of series connection, and described voltage sample ring regulating loop opens circuit or the output voltage when not connecing the LED lamp.

4. the constant current switch power supply of driving LED multi-path lamp as claimed in claim 1 is characterized in that, described secondary DC/DC transformation loop comprises the current sample ring.

5. the constant current switch power supply of driving LED multi-path lamp as claimed in claim 1 is characterized in that, the output voltage of second group of dc voltage circuit of described output is greater than the output voltage of first group of dc voltage circuit of output.

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