CN2840591Y - Adjustable brightness HID lamp driving circuit - Google Patents

Abstract

The utility model relates to an HID lamp driving circuit capable of adjusting brightness. The utility model is mainly characterized in that a power adjusting circuit is arranged between a voltage boosting circuit and a full-bridge circuit, and an analog-digital converting circuit is arranged between a control IC and the full-bridge circuit. In the way, the power adjusting circuit can adjust a power value of a power supply loop of the voltage boosting circuit and the full-bridge circuit; if the brightness of an HID headlamp needs to be lowered, the analog-digital converting circuit is made to be in an enabled state, and the full-bridge circuit outputs a lower-power DC driving power supply; inversely, when the brightness of the HID headlamp needs to be increased, the analog-digital converting circuit is not made to be in the enabled state, and the full-bridge circuit outputs a high-power AC driving voltage so that the HID headlamp is lighted in a high brightness mode. Therefore, the utility model can adjust the brightness of the HID headlamp by a driving circuit and benefits the development of the headlamps of different functions.

Description

The HID lamp drive circuit of adjustable brightness

Technical field

The utility model is about a kind of HID lamp (High Intensity Discharge Lamp) drive circuit, refers to a kind of HID lamp drive circuit of adjustable brightness especially, and possesses far and near lamp handoff functionality.

Background technology

Because vehicle uses the head lamp of halogen form mostly, make when vehicle travels that it is not enough that the brightness of Halogen Headlamp is disliked slightly in night or thick fog, be to enjoy liking of depot with present HID head lamp newly developed.

The HID head lamp has two kinds of specifications on the market: a kind of DC12V/35W of being; Another kind is the specification of DC24V/35W, and the brightness after it is lighted is three times of Halogen Headlamp.Though the HID head lamp has the illumination functions of high brightness, but because there is not brightness control function, make meeting the other side in season send a car because the high light of HID head lamp causes the visual impact of dazzle, and then the harm traffic safety, this also is the disadvantage that present vehicle uses the HID head lamp.

Review Halogen Headlamp except brightness is more weak, have more intensity adjustable function, and make in two side's vehicle meetings, switch to the low beam pattern low light level, guarantee the other side's traffic safety by the driver.But the HID head lamp does not have this function at present, and in order to make the HID head lamp successfully to be widely used on the headlight, this problem certainly will will achieve a solution.

See also shown in Figure 6ly, be the drive circuit of HID head lamp at present, it includes:

One booster circuit 50 consists predominantly of a transformer 51 and a filter circuit 52, and wherein the primary side of this transformer 51 is connected to the input DC power of a 12V or 24V, and this direct-current input power supplying is boosted to about 85V high pressure;

One full-bridge circuit 60, be connected to filter circuit 52 outputs of this booster circuit 50, to obtain high voltage source, this full-bridge circuit 60 is made up of a PWM controller IC2 and four transistor Q9～Q12, this PWM controller IC2 system is by controlling one group transistor Q9/Q12 in twos periodically in regular turn, Q10/Q11 opens and closes, and exports the two power electrode BR-/BR+s of an AC driving electric current to the HID head lamp; And

One control IC (IC1), be connected to the PWM controller IC2 of booster circuit 50 and full-bridge circuit 60 respectively, so as to learning this HID head lamp driving power situation, the numerical value that control transformer 51 boosts, and the control cycle of PWM controller IC2, give the HID head lamp to provide the stabilized driving AC power to keep the output of 35W power supply, make the HID head lamp can maintain the highlight illumination light source.

By the design of above-mentioned drive circuit as can be known, the HID head lamp is designed to drive and maintain 35W at present, can't adjust the size of its power output, if can be by reducing the power that drives the HID lamp, promptly can make the brightness deterioration of this HID head lamp, so, can be along with vehicle condition or environment adjust well-lit HID head lamp brightness of illumination.

Summary of the invention

For this reason, the utility model purpose provides a kind of HID lamp drive circuit of adjustable brightness, and the factory that can buy car in installments is according to environment or vehicle condition design diverter switch, and the brightness for the driver can adjust the HID head lamp makes its applicability wider.

The major technique means are to make this HID lamp drive circuit, include:

One power adjusting circuit is located between booster circuit and the full-bridge circuit, and it mainly comprises series resistance, a resistance in parallel and a switching circuit that is serially connected with between booster circuit and the full-bridge circuit; By the keying of control switch circuit, whether the decision series resistance is in parallel with parallel resistance, changes resistance value; And

One analog-to-digital conversion circuit is located between this control IC and the full-bridge circuit, and it includes an Enable Pin, and whether it enables to determine full-bridge circuit output alternating current drive circuit or DC driven power supply by external control.

Will be by the brightness deterioration of above-mentioned drive circuit control HID head lamp, difference control switch short circuit, make the resistance value of the electric power loop of booster circuit and full-bridge circuit reduce, change the power of driving power, the while also makes analog-to-digital conversion circuit enable, and the pulse-width modulation conversion of signals that the script control IC is exported to full-bridge circuit is a direct current signal, make this full-bridge circuit export a direct current driving power, so, compare with AC power and drive the HID head lamp, the brightness of this HID head lamp weakens naturally.Desire to make the HID head lamp to reply high brightness, also no longer control this analog-digital converter with regard to the off switch circuit and enable, can recover the driving of high brightness.

The utility model time purpose provides one and has the HID head lamp drive circuit that multi-segment brightness is adjusted function, be that above-mentioned power adjusting circuit further comprises plural groups parallel resistance and switching circuit, by controlling the keying of this switching circuit respectively, make the resistance value of electric power loop between booster circuit and the full-bridge circuit change, export the power of HID head lamp to and change, and reach the function that multi-segment brightness is adjusted.

The another purpose of the utility model provides one and has the HID head lamp drive circuit that does not have section brightness adjustment function, the parallel resistance that is about to above-mentioned power adjusting circuit is replaced with variable resistor, utilize variable-resistance adjustment, the resistance value that changes electric power loop between booster circuit and the full-bridge circuit changes, export the power of HID head lamp to and change, do not have the function that section brightness is adjusted and reach.

The accompanying drawing summary

Fig. 1 is the circuit diagram of the utility model first preferred embodiment.

Fig. 2 is the circuit diagram of the utility model second preferred embodiment.

Fig. 3 is the circuit diagram of the utility model the 3rd preferred embodiment.

Fig. 4 A is the sequential chart of the utility model analog-digital converter under high power mode.

Fig. 4 B is the sequential chart of the utility model analog-digital converter under low-power mode.

Fig. 5 is the detailed circuit diagram of the utility model digital analog converter.

Fig. 6 is the drive circuit figure of existing HID head lamp.

Embodiment

At first seeing also shown in Figure 1ly, is adjustable brightness of the utility model and HID lamp drive circuit figure, and it includes:

One booster circuit 10 consists predominantly of a transformer 11 and a filter circuit 12, and wherein the primary side of this transformer 11 is connected to the input DC power of a 6V to 32V, and this direct-current input power supplying is boosted to about 85V high pressure;

One full-bridge circuit 20, be connected to filter circuit 12 outputs of this booster circuit 10, to obtain high voltage source, this full-bridge circuit 20 mainly comprises a PWM controller IC2 and four transistor Q9～Q12, by a pair of in twos transistor Q9/Q12 of PWM controller IC2 control periodically in regular turn, Q10/Q11 opens and closes the cycle, and exports the two power electrode BR-/BR+s of an AC driving electric current to the HID head lamp;

One power adjusting circuit 30 is series between this booster circuit 10 and the full-bridge circuit 20, to change the resistance value of electric power loop, enters this full-bridge circuit 20 power outputs and adjust;

One control IC (IC1), be connected to the PWM controller IC2 of booster circuit 10 and full-bridge circuit 20 respectively, detect this HID head lamp driving power situation, control inputs to the magnitude of voltage of transformer 11 primary sides, and the control cycle of adjusting PWM controller IC2; And

One analog-digital converter 40, cooperate shown in Figure 5, be connected to the control end of this control IC (IC1) and PWM controller IC2 respectively, it includes an Enable Pin AC/DC, when it is controlled as enable mode, the pulse width signal that this control IC (IC1) exports this PWM controller IC2 originally to will be converted to direct current signal, again direct current signal is inputed to the control end of this pulse-width regulating device IC2, make PWM controller IC2 only control a wherein group transistor conducting Q9/Q12, another group transistor Q10/Q11 gives this HID head lamp power electrode (BR-/BR+) by being failure to actuate and directly export a high-voltage DC power supply.

Above-mentioned power adjusting circuit 30 has several preferred embodiments, and Fig. 1 discloses first preferred embodiment, and this power adjusting circuit 30 includes:

One series connection resistance R 8 is connected between booster circuit 10 and the full-bridge circuit 20, as the dividing potential drop effect; And

One resistance R 8-1 in parallel, after a switching circuit (not label) is connected, in parallel with this series resistance R8 again, the control end of this switching circuit is connected to one and switches signal Cont, wherein this switching circuit is made up of two transistor Q1/Q2, if use MOS transistor, the gate of this first MOS transistor Q1 is connected to the drain electrode of second MOS transistor, and the gate of the second MOS transistor Q2 then is connected to outside switching signal Cont;

When outside switching signal Cont is a positive potential signal, this second MOS transistor Q2 meeting conducting, and then make the first MOS transistor Q1 conducting, so this parallel resistance R8-1 is promptly in parallel with this series resistance R8, makes full-bridge circuit 20 obtain higher voltage.Simultaneously, please cooperate shown in Fig. 4 B, when outside switching signal Cont is positive potential, the Enable Pin of this analog-digital converter 40 can be at high potential, and after the pulse-width modulation signal QOUT/QOUT of control IC (IC1) output is converted to direct current signal, input to the control end of PWM controller IC2 again, at this moment, this PWM controller IC2 will only can drive a group transistor Q9/Q12 conducting, and will export two power electrode BR-/BR+ of HID head lamp to via the direct voltage of series/parallel resistance R 8/R8-1 step-down, driving the HID head lamp lights, compared to driving the HID head lamp with AC power, its brightness meeting of lighting weakens, and adjusts the purpose that power weakens brightness and reach.

Otherwise, if driving the HID head lamp, desire desires to recall to the high brightness pattern, shown in Fig. 4 A, this outside switching signal Cont can be electronegative potential, make switching circuit open circuit, recover the resistance value of former series resistance, no longer enable as for 40 of analog-digital converters, directly the pulse-width modulation signal QOUT/QOUT of control IC (IC1) output is exported to the control end of this PWM controller IC2, make this PWM controller IC2 that the restore cycle interaction opens and closes two group transistor Q9/Q12, Q10/Q11 exports an AC power to this HID head lamp, makes the HID head lamp be lighting of high brightness.

First preferred embodiment of above-mentioned power adjusting circuit, only comprise a resistance in parallel and a switching circuit, be that keying with switching circuit can only make the HID head lamp present the ignition mode of a kind of high brightness and a kind of low-light level, in brief, this preferred embodiment has two-period form and adjusts function.

Seeing also shown in Figure 2ly, be second preferred embodiment of the utility model power adjusting circuit 30a, is to disclose multisection type to adjust function, and it includes:

One series connection resistance R 8 is connected between booster circuit 10 and the full-bridge circuit 20, as the dividing potential drop effect; And

Plural number parallel resistance R8-1～R8-4, each parallel resistance R8-1～R8-4 is with after a switching circuit is connected, in parallel with this series resistance and other parallel resistance and switch road thereof again, and the control end of each switching circuit is connected to a corresponding switching signal Cont1～Cont4 respectively, wherein this switching circuit is made up of one-transistor Q1～Q4, if use MOS transistor, then its gate terminal is connected to outside switching signal;

This power adjusting circuit mainly comprises many group parallel resistances and switching circuit thereof, use different resistance values parallel resistance or once many group switching circuits to use the resistance of same resistance value by once lighting single group respectively, make its corresponding parallel resistance in parallel with series resistance, and the resistance value between change booster circuit and the full-bridge circuit, and then adjust output power value.

Except that preceding taking off two kinds of switch modes, the 3rd preferred embodiment of this power adjusting circuit 30b includes:

One series connection resistance R 8 is connected between booster circuit 10 and the full-bridge circuit 20, as the dividing potential drop effect; And

One variable resistor VR8-1 in parallel can be with after a resistance R 9 be connected, and is in parallel with this series resistance R8 again, so, by changing variable-resistance resistance, can reach the variation of not having the section resistance.

As shown in the above description, the utility model mainly HID drive circuit improvement originally is to have the function that power is adjusted, cooperate the control full-bridge circuit in switching high power mode output AC driving power, and under low-power mode, export dc drive circuit, effectively to reach the brightness of lowering present HID head lamp.And design of drive circuit of the present utility model has the input pin of switching signal and Enable Pin, make depot or car light factory can directly cooperate the design of its vehicle, design two sections, multistage even the section of nothing and adjust the function of brightness, not only can improve present HID head lamp does not effectively have the shortcoming that function is adjusted in brightness, has more quite wide application.

Claims (8)

1. the HID lamp drive circuit of an adjustable brightness is characterized in that, includes:

One booster circuit consists predominantly of a transformer and a filter circuit, and wherein the primary side of this transformer connects low-voltage dc power supply, output after this direct current input current potential is boosted;

One full-bridge circuit, be connected to the filter circuit output of this booster circuit, to obtain high voltage source, this full-bridge circuit mainly comprises a PWM controller and four transistors, open and close the cycle by a pair of in twos transistor of PWM controller control periodically in regular turn, and export two power electrodes of an AC driving electric current to the HID head lamp;

One power adjusting circuit is series between this booster circuit and the full-bridge circuit, uses the resistance value that changes electric power loop, adjusts the magnitude of voltage that enters this full-bridge circuit, and then adjusts power output;

One control IC is connected to the PWM controller of booster circuit and full-bridge circuit respectively, detects HID head lamp driving power situation, the input voltage value of control booster circuit transformer primary side, and PWM controller is adjusted its control cycle; And

One analog-digital converter, be connected to the control end of this control IC and PWM controller respectively, it comprises an Enable Pin, and the pulse width signal that control IC can be exported originally to this PWM controller when enabling will be converted to the control end that inputs to this pulse-width regulating device behind the direct current signal; Otherwise, the pulse-width modulation signal of control IC can be exported to the control end of this PWM controller.

2. the HID lamp drive circuit of adjustable brightness according to claim 1 is characterized in that this power adjusting circuit includes:

One series connection resistance is connected between booster circuit and the full-bridge circuit, as the dividing potential drop effect; And

One resistance in parallel, in parallel with this series resistance again after a switching circuit is connected, the control end of this switching circuit is connected to one and switches signal, by the keying of switching signal control switch circuit.

3. as the HID lamp drive circuit of adjustable brightness as described in the claim 2, it is characterized in that, this switching circuit is made up of two transistor, and wherein the gate of the first transistor is connected to the drain electrode of transistor seconds, and the gate of transistor seconds then is connected to outside switching signal.

4. the HID lamp drive circuit of adjustable brightness according to claim 1 is characterized in that this power adjusting circuit includes:

One series connection resistance is connected between booster circuit and the full-bridge circuit, as the dividing potential drop effect; And

Plural number parallel resistance, each parallel resistance be with after a switching circuit is connected, and be in parallel with this series resistance and other parallel resistance and switch road thereof again, and the control end of each switching circuit is connected to a corresponding switching signal respectively.

5. as the HID lamp drive circuit of adjustable brightness as described in the claim 4, it is characterized in that this switching circuit is an one-transistor, its gate terminal is connected to outside switching signal.

6. as the HID lamp drive circuit of adjustable brightness as described in claim 4 or 5, it is characterized in that plural parallel resistance has same resistance value.

7. as the HID lamp drive circuit of adjustable brightness as described in claim 4 or 5, it is characterized in that each parallel resistance is different resistance value.

8. the HID lamp drive circuit of adjustable brightness according to claim 1 is characterized in that this power adjusting circuit includes:

One series connection resistance is connected between booster circuit and the full-bridge circuit, as the dividing potential drop effect; And

One variable resistor in parallel can be with after a resistance be connected, and is in parallel with this series resistance again.

Images