CN109068435B - Automobile dimming circuit - Google Patents

Automobile dimming circuit Download PDF

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Publication number
CN109068435B
CN109068435B CN201810600724.8A CN201810600724A CN109068435B CN 109068435 B CN109068435 B CN 109068435B CN 201810600724 A CN201810600724 A CN 201810600724A CN 109068435 B CN109068435 B CN 109068435B
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resistor
chip
capacitor
port
led
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CN109068435A (en
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严章琴
钟健
高社科
刘玲
盛道学
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Ningbo Fulai Electronics Technology Co ltd
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Ningbo Fulai Electronics Technology Co ltd
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    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/10—Controlling the intensity of the light
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
    • Y02B20/40—Control techniques providing energy savings, e.g. smart controller or presence detection

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  • Circuit Arrangement For Electric Light Sources In General (AREA)
  • Lighting Device Outwards From Vehicle And Optical Signal (AREA)

Abstract

The application discloses an automobile dimming circuit, which relates to the technical field of automobile electronics, and relates to an optical sensor and an LED driving circuit; the light sensor (U3) is used for detecting light intensity and outputting a light intensity signal to the LED driving circuit; the LED driving circuit includes: the LED display device comprises a first chip (U1) and a second chip (U2), wherein the second chip (U2) is connected to a light sensor (U3), acquires a light intensity signal output by the light sensor (U3), and outputs a voltage signal to the first chip (U1) according to the light intensity signal, and the first chip (U1) is used for adjusting the brightness of an LED according to the voltage signal; the self-adaptive adjustment of the automobile light is realized. The application can replace manual adjustment, is convenient for drivers and improves the safety of the automobile driving at night.

Description

Automobile dimming circuit
Technical Field
The application relates to the technical field of automobile electronics, in particular to an automobile dimming circuit.
Background
Automobiles typically include a light assembly that provides several different light functions. For example, light assemblies typically have a high beam/low beam (HB/LB) function, a Daytime Running Light (DRL) function, and a position light (position light) function. The high beam/low beam lights illuminate the roadway in front of the vehicle, allowing the driver to see the roadway in low light conditions. The headlight (including a high beam and a low beam, abbreviated as a headlight) can provide a light with high brightness and a long range to illuminate a road on which a vehicle is traveling, and also allows an opposite driver or pedestrian to see the vehicle in advance at night. However, at night, the brightness of the headlights may need to be controlled in special situations. When a pedestrian or a vehicle approaches the surface, short blindness, especially for driving a bicycle or a non-motor vehicle, can be caused by the strong light of the headlight, which is very dangerous. Thus, the application of the adaptive dimming system for the automotive headlamp has very important significance.
At present, most vehicles cannot adjust the brightness of a headlight according to the intensity of ambient light, which causes unnecessary safety problems.
Disclosure of Invention
The technical problem to be solved by the application is to provide an automobile dimming circuit aiming at the defects in the prior art, so that an automobile can adjust the brightness of the self-lamplight according to the ambient light brightness.
In order to solve the above technical problems, the present application provides an automotive dimming circuit, which includes:
a light sensor (U3) for detecting light intensity and outputting a light intensity signal to the LED driving circuit;
an LED drive circuit comprising a first chip (U1), a second chip (U2); the second chip (U2) is connected to the optical sensor (U3), acquires a light intensity signal output by the optical sensor (U3), and outputs a voltage signal to the first chip (U1) according to the light intensity signal; the voltage input end (VCC) is respectively connected to the negative electrode of the LED and one end of the first inductor (L2); the other end of the first inductor (L2) is respectively connected to the drain electrode of the NMOS tube (Q2) and the anode of the first diode (D4); the source electrode of the NMOS tube (Q2) is grounded through a first resistor (R22) and a second resistor (R23) which are connected in parallel; the negative electrode of the first diode (D4) is respectively connected to one ends of a third resistor (R2), a fourth resistor (R3) and a fifth resistor (R5); the other ends of the third resistor (R2) and the fourth resistor (R3) are connected to the source electrode of the PMOS tube (Q1), and the other end of the fifth resistor (R5) is respectively connected to the grid electrode of the PMOS tube (Q1) and the collector electrode of the triode (Q3); the drain electrode of the PMOS tube (Q1) is connected to the anode of the LED; the emitter of the triode (Q3) is grounded;
a first port (SWDRV) of the first chip (U1) is connected to the grid electrode of the NMOS tube (Q2), a second port (CS) is connected to the source electrode of the NMOS tube (Q2), and a third port (PWMout) is connected to the base electrode of the triode (Q3);
the first chip (U1) controls the NMOS tube (Q2) to conduct on-off circulation, so that the first inductor (L2) is continuously charged and discharged; when the first chip (U1) controls the triode (Q3) to be continuously conducted, the LED emits light; the first chip (U1) controls the duty ratio of the conduction time of the triode (Q3) according to the voltage signal of the second chip (U2) so as to adjust the brightness of the LED.
Optionally, a fourth port (DRL) of the first chip (U1) is connected to the control input; when the first chip (U1) detects that the control input end has input voltage, the conduction time of the triode (Q3) is adjusted to a preset time duty ratio.
Optionally, a fifth port (IMP) and a sixth port (IMN) of the first chip (U1) are respectively connected to both ends of the third resistor (R2) to detect a voltage across the third resistor (R2); the first chip (U1) calculates a current value on the third resistor (R2) according to the voltage at two ends of the third resistor (R2), and adjusts control signals output by the first port (SWDRV), the second port (CS) and the third port (PWMout) according to the current value.
Optionally, the negative electrode of the first diode (D4) is respectively connected to one ends of the third resistor (R2), the fourth resistor (R3) and the fifth resistor (R5) specifically: the cathode of the first diode (D4) is respectively connected to one ends of the third resistor (R2), the fourth resistor (R3) and the fifth resistor (R5) through the magnetic beads (B1).
Optionally, one end of the magnetic bead (B1) is connected to one end of the first capacitor (C10), the second capacitor (C11) and the third capacitor (C9), and the other end is connected to one end of the fourth capacitor (C12); the other ends of the first capacitor (C10), the second capacitor (C11), the third capacitor (C9) and the fourth capacitor (C12) are grounded.
Optionally, the automobile dimming circuit further comprises a fifth capacitor (C7), one end of the fifth capacitor (C7) is connected to the negative electrode of the LED, and the other end of the fifth capacitor is connected to one end of the fifth resistor (R5) connected with the magnetic bead (B1).
Optionally, the third Port (PWMOUT) of the first chip (U1) is connected to the base of the transistor (Q3) through a sixth resistor (R18); the base electrode of the triode (Q3) is grounded through a seventh resistor (R20) and a sixth capacitor (C21) respectively; the emitter of the triode (Q3) is grounded through an eighth resistor (R21).
Optionally, a seventh capacitor (C15) is connected between the collector and the base of the transistor (Q3); an eighth capacitor (C20) is connected between the emitter and collector of the triode (Q3).
The technical scheme of the application relates to a light sensor and an LED driving circuit; the light sensor (U3) is used for detecting light intensity and outputting a light intensity signal to the LED driving circuit; the LED driving circuit includes: the LED display device comprises a first chip (U1) and a second chip (U2), wherein the second chip (U2) is connected to a light sensor (U3), acquires a light intensity signal output by the light sensor (U3), and outputs a voltage signal to the first chip (U1) according to the light intensity signal, and the first chip (U1) is used for adjusting the brightness of an LED according to the voltage signal; the self-adaptive adjustment of the automobile light is realized. The application can replace manual adjustment, is convenient for drivers and improves the safety of the automobile driving at night.
Drawings
Fig. 1 is a circuit schematic diagram of an automotive dimming circuit, according to an example embodiment.
Fig. 2 is a circuit schematic of a power supply circuit shown according to an example embodiment.
Detailed Description
The following are specific embodiments of the present application and the technical solutions of the present application will be further described with reference to the accompanying drawings, but the present application is not limited to these embodiments.
Referring to fig. 1, fig. 1 is a schematic circuit diagram of an automotive dimming circuit according to an exemplary embodiment of the present application. The automobile dimming circuit includes:
the light sensor U3 is configured to detect light intensity and output a light intensity signal to the LED driving circuit.
The LED driving circuit comprises a first chip U1 and a second chip U2; the second chip U2 is connected to the optical sensor U3, acquires a light intensity signal output by the optical sensor U3, and outputs a voltage signal to the first chip U1 according to the light intensity signal; the voltage input end VCC is respectively connected to the cathode of the LED and one end of the first inductor L2; the other end of the first inductor L2 is respectively connected to the drain electrode of the NMOS tube Q2 and the anode of the first diode D4; the source electrode of the NMOS tube Q2 is grounded through a first resistor R22 and a second resistor R23 which are connected in parallel; the negative electrode of the first diode D4 is respectively connected to one ends of a third resistor R2, a fourth resistor R3 and a fifth resistor R5; the other ends of the third resistor R2 and the fourth resistor R3 are connected to the source electrode of the PMOS tube Q1, and the other end of the fifth resistor R5 is respectively connected to the grid electrode of the PMOS tube Q1 and the collector electrode of the triode Q3; the drain electrode of the PMOS tube Q1 is connected to the anode of the LED; the emitter of the triode Q3 is grounded;
a first port SWDRV of the first chip U1 is connected to the grid electrode of the NMOS tube Q2, a second port CS is connected to the source electrode of the NMOS tube Q2, and a third port PWMout is connected to the base electrode of the triode Q3;
the first chip U1 controls the NMOS tube Q2 to conduct on-off circulation, so that the first inductor L2 is continuously charged and discharged; when the first chip U1 controls the triode Q3 to be continuously conducted, the LED emits light; the first chip U1 controls the duty ratio of the conduction time of the triode Q3 according to the voltage signal of the second chip U2 so as to adjust the brightness of the LED.
In the embodiment of the present application, the port OUT of the optical sensor U3 outputs the optical intensity signal to the port GP2 of the second chip U2. Specifically, the port GP2 of the second chip U2 is connected to one end of the resistor R24 and one end of the resistor R25, respectively, the other end of the resistor R24 is connected to the port OUT of the optical sensor U3, and the other end of the resistor R25 is grounded.
The port GP5 of the second chip U2 is connected to the port RESET of the light sensor U3, and the second chip U2 may issue a RESET signal to the light sensor U3 to RESET the light sensor U3.
In the embodiment of the present application, the second chip U2 is connected to the optical sensor U3, acquires the light intensity signal output by the optical sensor U3, and outputs the voltage signal to the first chip U1 according to the light intensity signal. Specifically, the GP4 of the second chip U2 is connected to the first chip U1 through the resistor R26 to output a voltage signal related to the light intensity to the first chip U1. The first chip U1 may adjust the brightness of the LED according to the voltage signal.
In this embodiment, the first chip U1 may control the transistor Q3 to be continuously turned on; when the triode Q3 is turned on, the gate voltage of the PMOS tube Q1 is reduced, so that the PMOS tube is turned on, and at this time, the voltage of the voltage input end VCC can be applied to the anode of the LED.
When the first port SWDRV of the first chip U1 outputs a low level, the NMOS tube Q2 can be cut off, the positive voltage of the LED does not exceed the negative voltage, and the LED does not emit light. When the first port SWDRV outputs a high level, the NMOS transistor Q2 may be turned on, and the first inductor L2 discharges through the NMOS transistor Q2, the first resistor R22, and the second resistor R23, to generate a discharge voltage, and the discharge voltage is superimposed with a voltage provided by the voltage input terminal VCC, so that the positive voltage of the LED exceeds the negative voltage, and the LED emits light. When the first port SWDRV of the first chip U1 can continuously switch between high level and low level, the NMOS Q2 is cycled on and off, so that the first inductor L2 is continuously charged and discharged, and the LED emits light.
The LED emits light not only continuously but also at a constant frequency, and the LED emits light and blinks at a high rate, which is considered to be a normally bright state.
The first chip U1 controls the duty ratio of the conduction time of the triode Q3 according to the voltage signal of the second chip U2 so as to adjust the brightness of the LED. When the first chip U1 controls the triode Q3 to be cut off, the grid electrode of the PMOS tube Q1 is in a high level, the PMOS tube Q1 is cut off, the anode of the LED loses voltage, and the LED does not emit light. Further, the proportion of the conducting time of the triode Q3 can be controlled through the first chip U1, the proportion of the light-emitting time of the LED is adjusted, and the brightness of the LED is adjusted.
It should be noted that, by controlling the on and off of the transistor Q3 and controlling the on and off of the PMOS transistor Q1, the proportion of the on time of the PMOS transistor Q1 is adjusted.
Note that, the proportion of the on time of the transistor Q3, that is, the proportion of the on time of the transistor Q3 is the proportion of the on time of the transistor Q3 to the sum of the on time and the off time. Since the first chip U1 can control the transistor Q3 to switch between on and off states at high speed, the LED flashes at high speed, which is a normally bright state in appearance. The longer the elapsed time, the greater the brightness.
The first chip U1 controls the duty ratio of the conduction time of the triode Q3 according to the voltage signal of the second chip U2 so as to adjust the brightness of the LED; the voltage signal here is related to the light intensity detected by the light sensor U3, so that the brightness of the LED is adjusted according to the light intensity.
In the embodiment of the application, the fourth port DRL of the first chip U1 is connected to the control input end; when the first chip U1 detects that the control input terminal has an input voltage, the on time of the transistor Q3 is adjusted to a preset time duty ratio.
It should be noted that, the brightness of the LED can be switched between two levels by controlling the input end, so as to realize manual adjustment.
Further, the control input is connected to the fourth port DRL of the first chip U1 via a diode D3. The control input terminal is connected with the anode of the diode D3, and the cathode of the diode D3 is connected with the fourth port DRL.
In the embodiment of the present application, the fifth port IMP and the sixth port IMN of the first chip U1 are respectively connected to two ends of the third resistor R2, so as to detect voltages of two ends of the third resistor R2; the first chip U1 calculates a current value on the third resistor R2 according to the voltage at two ends of the third resistor R2, and adjusts control signals output by the first port SWDRV, the second port CS and the third port PWMout according to the current value.
The first chip U1 detects the voltage value of the two ends of the third resistor R2 through the fifth port IMP and the sixth port IMN, and further determines the current flowing through the third resistor R2 according to the voltage drop of the two ends of the third resistor R2.
Further, the first chip U1 adjusts the outputs of the first port SWDRV, the second port CS, and the third port PWMOUT according to the current flowing through the third resistor R2. This process corresponds to a feedback adjustment, wherein the current of the third resistor R2 is used to reflect the brightness level of the LED, and the current of the third resistor R2 is used to precisely adjust the lighting period of the LED.
In the embodiment of the present application, the negative electrode of the first diode D4 is connected to one ends of the third resistor R2, the fourth resistor R3, and the fifth resistor R5, respectively, specifically: the negative electrode of the first diode D4 is connected to one ends of the third resistor R2, the fourth resistor R3, and the fifth resistor R5 through the magnetic bead B1, respectively. The magnetic bead B1 is used for absorbing the ultrahigh frequency signal and enhancing the stability of the circuit.
In the embodiment of the application, one end of the magnetic bead B1 is connected to one end of the first capacitor C10, the second capacitor C11 and the third capacitor C9, and the other end is connected to one end of the fourth capacitor C12; the other ends of the first capacitor C10, the second capacitor C11, the third capacitor C9 and the fourth capacitor C12 are grounded.
In the embodiment of the application, the automobile dimming circuit further comprises a fifth capacitor C7, wherein one end of the fifth capacitor C7 is connected to the negative electrode of the LED, and the other end of the fifth capacitor C7 is connected to one end of the fifth resistor R5 connected to the magnetic bead B1.
The first capacitor C10, the second capacitor C11, the third capacitor C9, the fourth capacitor C12, and the fifth capacitor C7 are used for filtering.
The third port PWMOUT of the first chip U1 is connected to the base of the transistor Q3 through a sixth resistor R18; the base electrode of the triode Q3 is grounded through a seventh resistor R20 and a sixth capacitor C21 respectively; the emitter of the triode Q3 is grounded through an eighth resistor R21.
The voltage at the base of transistor Q3 is reduced by sixth resistor R18 and seventh resistor R20.
In the embodiment of the application, a seventh capacitor C15 is connected between the collector and the base of the triode Q3; an eighth capacitor C20 is connected between the emitter and collector of the transistor Q3.
The seventh capacitor C15 and the eighth capacitor C20 are used for filtering, so that the anti-interference capability is improved.
As shown in fig. 2, the automotive dimming circuit may further include a power circuit including: an input terminal PL and an input terminal DRL, the input terminal PL being connected to the anode of the zener diode D1; the input end DRL is connected to the anode of the zener diode D2; the cathode of the zener diode D2 and the cathode of the zener diode D1 are connected to one end of the bidirectional transient suppression diode TVS1, one end of the resistor R1 and one end of the capacitor C2; the other ends of the bidirectional transient suppression diode TVS1, the resistor R1 and the capacitor C2 are grounded; two input ends of the common-mode inductor L3 are respectively connected to two ends of the capacitor C2; one of the output ends of the common-mode inductor L3 is connected to one end of the inductor L1, one end of the capacitor C3 and one end of the capacitor C4; the other output end of the common-mode inductor L3, the other end of the capacitor C3 and the other end of the capacitor C4 are grounded; the other end of the inductor L1 is a voltage input end (VCC) and is grounded through a capacitor C5, a capacitor C6 and a capacitor C1.
In the power supply circuit, a capacitor C2, a capacitor C3, a capacitor C4, a capacitor C5, a capacitor C6, and a capacitor C1 are used for filtering. The bidirectional transient suppression diode TVS1 is used to protect circuit elements. The zener diode D1 and the zener diode D2 are used to filter the reverse voltage. The common mode inductance L3 is used to filter out common mode interference.
In an embodiment of the application, the power supply circuit is configured to provide a stable voltage output, i.e. a stable voltage at the voltage input (VCC).
The technical scheme of the application relates to a light sensor and an LED driving circuit; the light sensor U3 is used for detecting light intensity and outputting a light intensity signal to the LED driving circuit; the LED driving circuit includes: the LED light source comprises a first chip U1 and a second chip U2, wherein the second chip U2 is connected to a light sensor U3, acquires a light intensity signal output by the light sensor U3, and outputs a voltage signal to the first chip U1 according to the light intensity signal, and the first chip U1 is used for adjusting the brightness of an LED according to the voltage signal; the self-adaptive adjustment of the automobile light is realized. The application can replace manual adjustment, is convenient for drivers and improves the safety of the automobile driving at night.
The specific embodiments described herein are offered by way of example only to illustrate the spirit of the application. Those skilled in the art may make various modifications or additions to the described embodiments or substitutions thereof without departing from the spirit of the application or exceeding the scope of the application as defined in the accompanying claims.

Claims (7)

1. An automotive dimmer circuit, comprising:
a light sensor (U3) for detecting light intensity and outputting a light intensity signal to the LED driving circuit;
an LED drive circuit comprising a first chip (U1), a second chip (U2); the second chip (U2) is connected to the optical sensor (U3), acquires a light intensity signal output by the optical sensor (U3), and outputs a voltage signal to the first chip (U1) according to the light intensity signal; the voltage input end (VCC) is respectively connected to the negative electrode of the LED and one end of the first inductor (L2); the other end of the first inductor (L2) is respectively connected to the drain electrode of the NMOS tube (Q2) and the anode of the first diode (D4); the source electrode of the NMOS tube (Q2) is grounded through a first resistor (R22) and a second resistor (R23) which are connected in parallel; the negative electrode of the first diode (D4) is respectively connected to one ends of a third resistor (R2), a fourth resistor (R3) and a fifth resistor (R5); the other ends of the third resistor (R2) and the fourth resistor (R3) are connected to the source electrode of the PMOS tube (Q1), and the other end of the fifth resistor (R5) is respectively connected to the grid electrode of the PMOS tube (Q1) and the collector electrode of the triode (Q3); the drain electrode of the PMOS tube (Q1) is connected to the anode of the LED; the emitter of the triode (Q3) is grounded;
a first port (SWDRV) of the first chip (U1) is connected to the grid electrode of the NMOS tube (Q2), a second port (CS) is connected to the source electrode of the NMOS tube (Q2), and a third port (PWMout) is connected to the base electrode of the triode (Q3);
the first chip (U1) controls the NMOS tube (Q2) to conduct on-off circulation, so that the first inductor (L2) is continuously charged and discharged; when the first chip (U1) controls the triode (Q3) to be continuously conducted, the LED emits light; the first chip (U1) controls the duty ratio of the conduction time of the triode (Q3) according to the voltage signal of the second chip (U2) so as to adjust the brightness of the LED;
the fifth port (IMP) and the sixth port (IMN) of the first chip (U1) are respectively connected to two ends of the third resistor (R2) so as to detect the voltage of the two ends of the third resistor (R2); the first chip (U1) calculates a current value on the third resistor (R2) according to the voltage at two ends of the third resistor (R2), and adjusts control signals output by the first port (SWDRV), the second port (CS) and the third port (PWMout) according to the current value.
2. The automotive dimmer circuit according to claim 1, characterized in that the fourth port (DRL) of the first chip (U1) is connected to the control input; when the first chip (U1) detects that the control input end has input voltage, the conduction time of the triode (Q3) is adjusted to a preset time duty ratio.
3. The dimming circuit of an automobile according to claim 1, wherein the cathodes of the first diode (D4) are respectively connected to one end of a third resistor (R2), a fourth resistor (R3) and a fifth resistor (R5): the cathode of the first diode (D4) is respectively connected to one ends of the third resistor (R2), the fourth resistor (R3) and the fifth resistor (R5) through the magnetic beads (B1).
4. A dimming circuit for a vehicle according to claim 3, wherein one end of the magnetic bead (B1) is connected to one end of the first capacitor (C10), the second capacitor (C11), the third capacitor (C9), and the other end is connected to one end of the fourth capacitor (C12); the other ends of the first capacitor (C10), the second capacitor (C11), the third capacitor (C9) and the fourth capacitor (C12) are grounded.
5. The automotive dimming circuit according to claim 4, further comprising a fifth capacitor (C7), one end of the fifth capacitor (C7) being connected to the negative electrode of the LED, and the other end being connected to the end of the fifth resistor (R5) connected to the magnetic bead (B1).
6. The dimming circuit according to claim 1, characterized in that the third Port (PWMOUT) of the first chip (U1) is connected to the base of the transistor (Q3) through a sixth resistor (R18); the base electrode of the triode (Q3) is grounded through a seventh resistor (R20) and a sixth capacitor (C21) respectively; the emitter of the triode (Q3) is grounded through an eighth resistor (R21).
7. The dimming circuit of claim 6, wherein a seventh capacitor (C15) is connected between the collector and the base of the transistor (Q3); an eighth capacitor (C20) is connected between the emitter and collector of the triode (Q3).
CN201810600724.8A 2018-06-12 2018-06-12 Automobile dimming circuit Active CN109068435B (en)

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CN109451637B (en) * 2018-12-24 2024-01-30 上海源悦汽车电子股份有限公司 Automobile combined tail lamp braking effect control circuit
CN113286397B (en) * 2021-06-01 2023-08-25 上海市共进通信技术有限公司 Intelligent Circuit Structure for Realizing LED Brightness

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US9131583B2 (en) * 2013-03-01 2015-09-08 Shenzhen China Star Optoelectronics Technology Co., Ltd. LED backlight drive circuit
CN106028516A (en) * 2016-06-08 2016-10-12 成都昂迪加科技有限公司 Signal amplification circuit based light-control LED (Light-Emitting Diode) energy-saving control system
CN106793245B (en) * 2016-11-22 2018-09-04 聊城市科特祥瑞新能源有限公司 Light-operated LED car headlight control device

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