HUD backlight boost drive circuit
By optimizing the circuit structure of the HUD backlight boost drive circuit and using low-cost chips and resistor adjustment, the problems of difficult frequency adjustment and high power consumption were solved, achieving adjustable output power and low-cost design that can adapt to multiple LED lights.
Patent Information
- Application Number
- CN202422480095.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-14
- Publication Date
- 2025-09-05
- Estimated Expiration
- 2034-10-14
AI Technical Summary
The existing HUD backlight boost drive circuit has difficulty in frequency adjustment, is not suitable for multiple LED lights, has high power consumption and high cost.
The design includes a main chip, N light-emitting diodes, a current regulation circuit, a voltage regulation circuit and a backlight voltage output circuit. The circuit structure is optimized using components such as resistors and transistors. The low-cost chip SA32756QEQ is used to adjust the current and voltage by adjusting the resistors, thereby optimizing the pulse width duty cycle.
The output power is adjustable, power consumption is reduced, circuit structure is simplified, chip cost is reduced, and the device is suitable for use with multiple LED lamps.
Smart Images
Figure CN223308751U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of head-up display systems, in particular to a HUD backlight boost driving circuit. Background Art
[0002] HUD, short for Head-Up Display, also known as a head-up display system, is commonly used in automobiles. Its function is to project important driving information such as speed and navigation onto the windshield in front of the driver, allowing the driver to see these information without looking down or turning their head. Existing HUD backlight boost driver circuits have difficulty adjusting the frequency, are not compatible with a large number of LED lights, and consume high power and are costly. Summary of the Invention
[0003] The utility model provides a HUD backlight boost driving circuit, aiming to solve the problem of difficult frequency adjustment in the existing HUD backlight boost driving circuit design.
[0004] The utility model provides a HUD backlight boost driving circuit, which includes a main chip, N light-emitting diodes, a current regulating circuit, a voltage regulating circuit and a backlight voltage output circuit. The N light-emitting diodes are connected in series, the input end of the current regulating circuit is connected to the main chip, the output end of the backlight voltage output circuit and the output end of the current regulating circuit are connected to the positive electrode of the light-emitting diode D1, the negative electrode of the light-emitting diode DN is connected to the main chip, and the voltage regulating circuit is connected to the positive electrode of the light-emitting diode D1; the current regulating circuit includes a resistor R513 and a resistor R507, one end of the resistor R513 is connected to pin 31 of the main chip, the other end of the resistor R513 is connected to one end of the resistor R507, and the other end of the resistor R507 is connected to the positive electrode of the light-emitting diode D1; the voltage regulating circuit includes an adjusting resistor R501, one end of the adjusting resistor R501 is grounded, and the other end of the adjusting resistor R501 is connected to the positive electrode of the light-emitting diode D1.
[0005] As a further improvement of the present invention, the backlight voltage output circuit includes a transistor Q501, a resistor R511, an inductor L502, a diode D501, a capacitor C505, a capacitor C511 and a capacitor C514, one end of the resistor R511 is connected to pin 27 of the main chip, the other end of the resistor R511 is connected to the gate of the transistor Q501, the source of the transistor Q501 is connected to the other end of the resistor R507, and the drain of the transistor Q501 is connected to the positive electrode of the diode D501. The cathode of diode D501 is connected to the anode of light-emitting diode D1, one end of inductor L502 is connected to the anode of diode D501, the other end of inductor L502 is connected to 12V voltage, the anode of capacitor C505 is connected to the cathode of diode D501, one end of capacitor C511 is connected to the cathode of diode D501, one end of capacitor C514 is connected to the cathode of diode D501, the cathode of capacitor C505, the other end of capacitor C511 and the other end of capacitor C514 are all grounded.
[0006] As a further improvement of the present invention, it also includes a power control circuit, which includes a transistor Q502 and a resistor R504, one end of the resistor R504 is connected to the control switch, the other end of the resistor R504 is connected to pin 24 of the main chip, the gate of the transistor Q502 is connected to pin 21 of the main chip, the source of the transistor Q502 is connected to the other end of the inductor L502, and the drain of the transistor Q502 is connected to a 12V voltage.
[0007] As a further improvement of the present invention, an overvoltage protection circuit is also included, which includes a resistor R503 and a resistor R508. One end of the resistor R503 is connected to the other end of the adjustment resistor R501, the other end of the resistor R503 is connected to one end of the resistor R508, and the other end of the resistor R508 is connected to the positive electrode of the light-emitting diode D1.
[0008] As a further improvement of the present invention, it also includes a voltage detection circuit, which includes a resistor R505 and a resistor R510. One end of the resistor R505 is connected to pin 18 of the main chip, and the other end of the resistor R505 is grounded. One end of the resistor R510 is connected to a 12V voltage, and the other end of the resistor R510 is connected to pin 18 of the main chip.
[0009] As a further improvement of the present invention, it also includes resistors R509, R518, R514 and R512. One end of the resistor R509 is connected to pin 17 of the main chip, one end of the resistor R518 is connected to pin 16 of the main chip, one end of the resistor R514 is connected to pin 15 of the main chip, one end of the resistor R512 is connected to pin 14 of the main chip, and the other end of the resistor R509, the other end of the resistor R518, the other end of the resistor R514 and the other end of the resistor R512 are all grounded.
[0010] As a further improvement of the present invention, a dimming control resistor R506 is further included, one end of the dimming control resistor R506 is connected to the pulse width modulation signal, and the other end of the dimming control resistor R506 is connected to pin 12 of the main chip.
[0011] As a further improvement of the present invention, the cathode of the light-emitting diode DN is connected to pins 1, 2, 3, 5, 6, and 7 of the main chip, and the voltage of pins 1, 2, 3, 5, 6, and 7 of the main chip to ground is lower than 5V.
[0012] As a further improvement of the present invention, the model of the main chip is SA32756QEQ.
[0013] The beneficial effects of the utility model are: the output power of the circuit is adjustable, the external MOS tube is turned off to reduce power consumption, and the chip cost is low; and the practical and commonly used resistance and capacitance parameters in the circuit are optimized, and the pulse width duty cycle adjustment method is simple. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 It is a specific connection diagram of the circuit of the utility model. DETAILED DESCRIPTION
[0015] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.
[0016] like Figure 1As shown, the utility model provides a HUD backlight boost drive circuit, including a main chip, N light-emitting diodes, a current regulation circuit, a voltage regulation circuit and a backlight voltage output circuit. The N light-emitting diodes are connected in series, the input end of the current regulation circuit is connected to the main chip, the output end of the backlight voltage output circuit and the output end of the current regulation circuit are connected to the positive electrode of the light-emitting diode D1, the negative electrode of the light-emitting diode DN is connected to the main chip, and the voltage regulation circuit is connected to the positive electrode of the light-emitting diode D1; the current regulation circuit includes a resistor R513 and a resistor R507, one end of the resistor R513 is connected to pin 31 of the main chip, the other end of the resistor R513 is connected to one end of the resistor R507, and the other end of the resistor R507 is connected to the positive electrode of the light-emitting diode D1; the voltage regulation circuit includes a regulating resistor R501, one end of the regulating resistor R501 is grounded, and the other end of the regulating resistor R501 is connected to the positive electrode of the light-emitting diode D1.
[0017] As an embodiment of the present invention, the backlight voltage output circuit includes a transistor Q501, a resistor R511, an inductor L502, a diode D501, a capacitor C505, a capacitor C511 and a capacitor C514, one end of the resistor R511 is connected to pin 27 of the main chip, the other end of the resistor R511 is connected to the gate of the transistor Q501, the source of the transistor Q501 is connected to the other end of the resistor R507, and the drain of the transistor Q501 is connected to the positive electrode of the diode D501. The cathode of diode D501 is connected to the anode of light-emitting diode D1, one end of inductor L502 is connected to the anode of diode D501, the other end of inductor L502 is connected to 12V voltage, the anode of capacitor C505 is connected to the cathode of diode D501, one end of capacitor C511 is connected to the cathode of diode D501, one end of capacitor C514 is connected to the cathode of diode D501, the cathode of capacitor C505, the other end of capacitor C511 and the other end of capacitor C514 are all grounded.
[0018] As another embodiment of the present invention, it also includes a power control circuit, which includes a transistor Q502 and a resistor R504, one end of the resistor R504 is connected to the control switch, the other end of the resistor R504 is connected to pin 24 of the main chip, the gate of the transistor Q502 is connected to pin 21 of the main chip, the source of the transistor Q502 is connected to the other end of the inductor L502, and the drain of the transistor Q502 is connected to a 12V voltage.
[0019] As another embodiment of the present invention, an overvoltage protection circuit is also included, which includes a resistor R503 and a resistor R508. One end of the resistor R503 is connected to the other end of the adjustment resistor R501, the other end of the resistor R503 is connected to one end of the resistor R508, and the other end of the resistor R508 is connected to the positive electrode of the light-emitting diode D1.
[0020] As another embodiment of the present invention, it also includes a voltage detection circuit, which includes a resistor R505 and a resistor R510. One end of the resistor R505 is connected to pin 18 of the main chip, and the other end of the resistor R505 is grounded. One end of the resistor R510 is connected to a 12V voltage, and the other end of the resistor R510 is connected to pin 18 of the main chip.
[0021] As another embodiment of the present invention, it also includes a resistor R509, a resistor R518, a resistor R514 and a resistor R512, one end of the resistor R509 is connected to pin 17 of the main chip, one end of the resistor R518 is connected to pin 16 of the main chip, one end of the resistor R514 is connected to pin 15 of the main chip, one end of the resistor R512 is connected to pin 14 of the main chip, and the other end of the resistor R509, the other end of the resistor R518, the other end of the resistor R514 and the other end of the resistor R512 are all grounded.
[0022] As another embodiment of the present invention, a dimming control resistor R506 is further included. One end of the dimming control resistor R506 is connected to the pulse width modulation signal, and the other end of the dimming control resistor R506 is connected to pin 12 of the main chip.
[0023] As another embodiment of the present invention, the cathode of the light-emitting diode DN is connected to pins 1, 2, 3, 5, 6, and 7 of the main chip, and the voltage of pins 1, 2, 3, 5, 6, and 7 of the main chip to ground is lower than 5V.
[0024] As another embodiment of the present invention, the model of the main chip is SA32756QEQ.
[0025] This utility model provides a HUD backlight boost driver circuit. This circuit utilizes Silergy's latest low-cost chip, the SA32756QEQ. This design optimizes the circuit structure and main power supply ripple, reducing product failure rates. It also eliminates discrepant resistor parameters, allowing for greater uniformity using conventional materials. This circuit requires only resistors R513 and R507 for current regulation, while adjusting resistor R501 for voltage regulation, varying the voltage across 6-12 LEDs.
[0026] The circuit works as follows:
[0027] Power standby: After input from pin 23 of the main chip, the output from pin 21 of the main chip controls transistor Q502 to turn off the output;
[0028] Voltage detection: Resistor R510 and resistor R505 divide the voltage and input it to pin 18 of the main chip for detection;
[0029] Chip working mode selection: connected to pin 17 of the main chip through resistor R509 for adjustment;
[0030] Switching frequency adjustment: connected to pin 16 of the main chip through resistor R518, the frequency is 400KHz;
[0031] Dimming frequency adjustment: connected to pin 15 of the main chip through resistor R514, which is adjusted to 2441Hz high-frequency flicker-free dimming;
[0032] Current channel detection setting: connected to the 14-pin adjustment of the main chip through resistor R512, fixed 6-in-1 channel;
[0033] Dimming control input: 0-100% duty cycle is connected to pin 13 of the main chip through the dimming control resistor R506;
[0034] Output backlight voltage: The switching frequency is controlled by the main chip's pin 27. The transistor Q501 and the inductor L502 oscillate and then the rectifier is output by the diode D501. The capacitor C505 filters the low-frequency dimming ripple. The capacitors C511 and C514 filter the high-frequency oscillation ripple to make the output ripple lower.
[0035] Current detection: fine-tune the circuit demand current through resistor R513 and resistor R507;
[0036] Overvoltage protection circuit: Through fine-tuning of capacitors R508 and R503, adjust resistor R501 so that the maximum output power does not exceed the limit value. The total voltage required by the LED lamp + 4V = the limit value;
[0037] LED cathode output: Pins 1-3 and 5-7 of the main chip should be below 5V relative to ground (under both low and full load conditions). Designing for a voltage too high can cause the chip to overheat. Power consumption is calculated as LED voltage * LED current = output power.
[0038] The present invention has the following advantages over the prior art:
[0039] Adjustable output power: can be adapted to a circuit with N light-emitting diodes connected in series. In this utility model, the value range of N is 6-12;
[0040] Low power consumption: Optimized circuit structure, external MOS tube shuts down the back stage to reduce power consumption;
[0041] Low chip cost: It optimizes the practical and commonly used resistance and capacitance parameters in the circuit and simplifies the adjustment method of the pulse width and duty cycle.
[0042] The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention cannot be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.
Claims
1. A HUD backlight boost drive circuit, characterized in that: The device comprises a main chip, N light-emitting diodes, a current regulating circuit, a voltage regulating circuit and a backlight voltage output circuit. The N light-emitting diodes are connected in series. The input end of the current regulating circuit is connected to the main chip. The output end of the backlight voltage output circuit and the output end of the current regulating circuit are connected to the positive electrode of the light-emitting diode D1. The negative electrode of the light-emitting diode DN is connected to the main chip. The voltage regulating circuit is connected to the positive electrode of the light-emitting diode D1. The current regulating circuit comprises a resistor R513 and a resistor R507. One end of the resistor R513 is connected to pin 31 of the main chip, the other end of the resistor R513 is connected to one end of the resistor R507, and the other end of the resistor R507 is connected to the positive electrode of the light-emitting diode D1. The voltage regulating circuit comprises a regulating resistor R501. One end of the regulating resistor R501 is grounded, and the other end of the regulating resistor R501 is connected to the positive electrode of the light-emitting diode D1.
2. The HUD backlight boost driving circuit according to claim 1, characterized in that: The backlight voltage output circuit includes a transistor Q501, a resistor R511, an inductor L502, a diode D501, a capacitor C505, a capacitor C511 and a capacitor C514, one end of the resistor R511 is connected to pin 27 of the main chip, the other end of the resistor R511 is connected to the gate of the transistor Q501, the source of the transistor Q501 is connected to the other end of the resistor R507, the drain of the transistor Q501 is connected to the anode of the diode D501, and the diode D501 is connected to the cathode of the diode D501. The cathode of capacitor C505 is connected to the anode of diode D501, one end of capacitor C511 is connected to the cathode of diode D501, one end of capacitor C514 is connected to the cathode of diode D501, and the cathode of capacitor C505, the other end of capacitor C511 and the other end of capacitor C514 are all grounded.
3. The HUD backlight boost driving circuit according to claim 2, characterized in that: It also includes a power control circuit, which includes a transistor Q502 and a resistor R504. One end of the resistor R504 is connected to the control switch, the other end of the resistor R504 is connected to pin 24 of the main chip, the gate of the transistor Q502 is connected to pin 21 of the main chip, the source of the transistor Q502 is connected to the other end of the inductor L502, and the drain of the transistor Q502 is connected to a 12V voltage.
4. The HUD backlight boost driving circuit according to claim 1, characterized in that: An overvoltage protection circuit is also included, which includes a resistor R503 and a resistor R508. One end of the resistor R503 is connected to the other end of the adjustment resistor R501, the other end of the resistor R503 is connected to one end of the resistor R508, and the other end of the resistor R508 is connected to the positive electrode of the light-emitting diode D1.
5. The HUD backlight boost driving circuit according to claim 1, characterized in that: It also includes a voltage detection circuit, which includes a resistor R505 and a resistor R510. One end of the resistor R505 is connected to pin 18 of the main chip, and the other end of the resistor R505 is grounded. One end of the resistor R510 is connected to a 12V voltage, and the other end of the resistor R510 is connected to pin 18 of the main chip.
6. The HUD backlight boost driving circuit according to claim 1, characterized in that: It also includes resistor R509, resistor R518, resistor R514 and resistor R512. One end of resistor R509 is connected to pin 17 of the main chip, one end of resistor R518 is connected to pin 16 of the main chip, one end of resistor R514 is connected to pin 15 of the main chip, one end of resistor R512 is connected to pin 14 of the main chip, and the other end of resistor R509, the other end of resistor R518, the other end of resistor R514 and the other end of resistor R512 are all grounded.
7. The HUD backlight boost driving circuit according to claim 1, characterized in that: It also includes a dimming control resistor R506, one end of the dimming control resistor R506 is connected to the pulse width modulation signal, and the other end of the dimming control resistor R506 is connected to the 12th pin of the main chip.
8. The HUD backlight boost driving circuit according to claim 1, wherein: The cathode of the light emitting diode DN is connected to pins 1, 2, 3, 5, 6, and 7 of the main chip, and the voltage of pins 1, 2, 3, 5, 6, and 7 of the main chip to ground is lower than 5V.
9. The HUD backlight boost driving circuit according to any one of claims 1 to 8, characterized in that: The model of the main chip is SA32756QEQ.