A new step-down circuit for automotive electronics

Abstract

The present invention belongs to the field of automotive electronic technology, specifically a new step-down circuit for automotive electronics, including: transistor Q1, transistor Q2, transistor Q3, and transistor Q5. Simple circuit structure and few components: The new circuit design is streamlined, and does not require complex control algorithms or large-size magnetic components. It can achieve efficient voltage reduction with only a small number of components, thereby reducing overall cost and volume. Low static power consumption: The circuit has extremely low power consumption under light load or standby state, which significantly extends the service life of the car battery and is particularly suitable for automotive electronic equipment that is on standby for a long time. High stability and strong load capacity: Compared with traditional discrete component circuits, the new circuit has greatly improved load capacity and voltage stability, and can meet the voltage accuracy and load requirements of different automotive electronic equipment. Wide adaptability: The new circuit can adjust the output voltage over a wide range, adapt to the needs of a variety of automotive electronic equipment, and is highly versatile.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile electronics, and in particular to a novel step-down circuit for automobile electronics. Background Art

[0002] Voltage reduction is a common and critical issue in automotive electronics design. Car batteries typically operate at 12V or 24V, while electronic devices such as sensors, controllers, and communication modules often operate at voltages far lower than the battery voltage. This necessitates a step-down circuit to convert the high voltage to the required low voltage. However, traditional step-down solutions have their limitations in practical applications, making it difficult to simultaneously meet the high reliability, low power consumption, and simplified design requirements of automotive electronics.

[0003] The traditional buck (buck) circuit is a common step-down method, efficiently converting input voltage into a stable output voltage. It operates through switching control in conjunction with magnetic components (such as inductors and transformers), achieving high efficiency. However, buck circuits are complex, requiring not only the design of magnetic components but also the integration of software algorithms for control. Extreme conditions such as vibration and temperature fluctuations in automotive electronics pose challenges to the reliability of magnetic components, while the implementation of software algorithms increases development and maintenance costs. Furthermore, due to the strong dynamic characteristics of buck circuits, excessive static power consumption and unstable output can occur under light or no-load conditions.

[0004] Another traditional step-down method uses circuits built with discrete components, such as a transistor and a Zener diode. While this type of circuit offers advantages in terms of simplicity and low cost, it also has significant disadvantages. Due to the limitations of the operating principles of transistors and Zener diodes, their load capacity is insufficient, resulting in significant output voltage fluctuations and difficulty meeting the high-precision voltage requirements of automotive electronics. Furthermore, when the load current is high, the transistors may overheat due to excessive power consumption, impacting system stability. Summary of the Invention

[0005] The object of the present invention is to provide a novel step-down circuit for automotive electronics to solve the problems raised in the above background technology.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a novel step-down circuit for automotive electronics, comprising:

[0007] Transistor Q1, transistor Q2, transistor Q3, transistor Q5;

[0008] The emitter of the transistor Q2 is grounded, the base of the transistor Q2 is connected to one end of the resistor R5 and one end of the resistor R7, the collector of the transistor Q2 is connected to the other end of the resistor R5, one end of the resistor R6, and the emitter of the transistor Q1, and the connection point of the emitter of the transistor Q1, the resistor R5, and the resistor R6 is a node 1;

[0009] The other end of the resistor R7, the other end of the resistor R6, and the collector of the transistor Q4 are connected to the power supply end;

[0010] The collector of the transistor Q4 is also connected to one end of the resistor R4 and the collector of the transistor Q5. The other end of the resistor R4 is connected to the collector of the transistor Q1 and the base of the transistor Q3. The connection point of the resistor R4, the collector of the transistor Q1 and the base of the transistor Q3 is a node 2.

[0011] The emitter of the transistor Q3 is connected to the base of the transistor Q5, and the connection point between the emitter of the transistor Q3 and the base of the transistor Q5 is a node 4;

[0012] The base of the transistor Q1 is connected to one end of the resistor R13, the other end of the resistor R13 is connected to one end of the resistor R9 and one end of the resistor R8, and the connection point of the resistors R13, R9 and R8 is a node 3, and the other end of the resistor R8 is grounded;

[0013] The emitter of the transistor Q5 is connected to the other end of the resistor R9, one end of the capacitor C1, and one end of the resistor R2, and the connection point between the emitter of the transistor Q5 and the resistor R9 is node 5. The other end of the capacitor C1 and the other end of the resistor R2 are connected and grounded.

[0014] Preferably, the transistor Q3 and the transistor Q5 form a Darlington circuit.

[0015] Preferably, the Darlington circuit and the transistor Q1 form a negative feedback circuit.

[0016] Preferably, the resistance value of the resistor R2 is 100Ω, the resistance value of the resistor R9 is 161kΩ, the resistance value of the resistor R8 is 10kΩ, the resistance value of the resistor R13 is 1kΩ, the resistance value of the resistor R4 is 100kΩ, the resistance value of the resistor R6 is 100kΩ, the resistance value of the resistor R5 is 100kΩ, and the resistance value of the resistor R7 is 100kΩ.

[0017] Preferably, the capacity of the capacitor C1 is 10UF.

[0018] Preferably, the resistor R2 is a variable resistor, and the variable curve type of the resistor R2 potentiometer is an A-type potentiometer.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] Simple circuit structure and few components: The new circuit design is streamlined and does not require complex control algorithms or large-sized magnetic components. It can achieve efficient voltage reduction with only a few components, thereby reducing overall cost and size.

[0021] Low quiescent power consumption: The circuit consumes very little power under light load or standby conditions, significantly extending the life cycle of the vehicle battery. It is particularly suitable for automotive electronic devices that are in standby mode for long periods of time.

[0022] High stability and strong load capacity: Compared with traditional discrete component circuits, the new circuit has significantly improved load capacity and voltage stability, and can meet the voltage accuracy and load requirements of different automotive electronic equipment.

[0023] Wide adaptability: The new circuit can adjust the output voltage over a wide range, adapting to the needs of various automotive electronic equipment and having high versatility. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a circuit principle diagram of the present invention;

[0025] Figure 2 This is a simulation waveform diagram of the voltage from 18V to 32V in the present invention. DETAILED DESCRIPTION

[0026] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0027] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0028] For example 1, please refer to Figure 1-2 The present invention provides a technical solution: a new step-down circuit for automotive electronics, comprising:

[0029] Transistor Q1, transistor Q2, transistor Q3, transistor Q5;

[0030] Among them, the emitter of the transistor Q2 is grounded, the base of the transistor Q2 is connected to one end of the resistor R5 and one end of the resistor R7, the collector of the transistor Q2 is connected to the other end of the resistor R5, one end of the resistor R6, and the emitter of the transistor Q1, and the connection point of the emitter of the transistor Q1, the resistor R5, and the resistor R6 is node 1; the other end of the resistor R7, the other end of the resistor R6, and the collector of the transistor Q4 are connected to the power supply end; the collector of the transistor Q4 is also connected to one end of the resistor R4 and the collector of the transistor Q5, and the other end of the resistor R4 is connected to the collector of the transistor Q1 and the base of the transistor Q3, and the resistor R4, the collector of the transistor Q1, and the base of the transistor Q3 are connected. The base connection point is node 2; the emitter of the transistor Q3 is connected to the base of the transistor Q5, and the connection point of the emitter of the transistor Q3 and the base of the transistor Q5 is node 4; the base of the transistor Q1 is connected to one end of the resistor R13, the other end of the resistor R13 is connected to one end of the resistor R9 and one end of the resistor R8, and the connection point of the resistors R13, R9 and R8 is node 3, and the other end of the resistor R8 is grounded; the emitter of the transistor Q5 is connected to the other end of the resistor R9, one end of the capacitor C1, and one end of the resistor R2, and the connection point of the emitter of the transistor Q5 and the resistor R9 is node 5, the other end of the capacitor C1 and the other end of the resistor R2 are connected and grounded.

[0031] The transistors Q3 and Q5 form a Darlington circuit. The Darlington circuit and transistor Q1 form a negative feedback circuit. The resistance of the resistor R2 is 100Ω, the resistance of the resistor R9 is 161kΩ, the resistance of the resistor R8 is 10kΩ, the resistance of the resistor R13 is 1kΩ, the resistance of the resistor R4 is 100kΩ, the resistance of the resistor R6 is 100kΩ, the resistance of the resistor R5 is 100kΩ, and the resistance of the resistor R7 is 100kΩ. The capacity of the capacitor C1 is 10UF. The resistor R2 is a variable resistor, and the variable curve type of the potentiometer of the resistor R2 is a type A potentiometer.

[0032] In automotive electronic systems, providing stable voltage is crucial for key components such as the MCU and MOSFET drivers. This circuit utilizes the characteristics of transistors and achieves stable voltage output through a sophisticated topology, effectively adapting to the complex and changing battery operating environment of automotive electronic systems. Its simple circuit structure requires only a small number of components to perform the voltage step-down function, significantly reducing material cost and design complexity. Furthermore, the circuit's output voltage is stable, minimizing voltage fluctuations under varying load conditions, providing a reliable power supply for sensitive components such as the MCU and MOSFET drivers. Furthermore, the circuit has a strong load capacity and can support high load currents, meeting the high-power supply requirements of automotive electronic equipment. Its low power consumption also effectively extends the life cycle of the vehicle battery, improving the efficiency and reliability of the entire vehicle system.

[0033] When the automotive system is connected to power, the buck circuit quickly starts and enters normal operation. Transistor Q2 is in the on state within the circuit, and the voltage at node 1 is stable. As a key node, it maintains circuit stability and provides the basis for precise control of subsequent circuits. Transistors Q3 and Q5 form a Darlington circuit, whose high gain enhances the circuit's load capacity. As the output voltage increases, the voltage at node 3 decreases, reducing the current through transistor Q1. This reduces the voltage drop across resistor R4, causing the voltage at node 2 to increase, increasing the current through transistor Q3 and, consequently, the current through node 5, which also increases the output voltage. This improves the circuit's output stability. This circuit requires an input voltage 4V greater than the output voltage and supports load currents exceeding 5A. This makes it easily capable of meeting the high power demands of modern automotive electronics.

[0034] Compared with traditional solutions, this step-down circuit offers significant advantages in terms of materials and cost. Through a streamlined transistor design and optimal component selection, the need for magnetic components and complex controllers is significantly reduced, significantly lowering production costs. Furthermore, the circuit's simple and easy-to-implement structure reduces design and manufacturing complexity, facilitating large-scale mass production applications.

[0035] In summary, this new step-down circuit not only meets the high performance standards of modern automotive electronics, but also reduces material costs and maintenance complexity through optimized design. It offers high stability and performance in extreme environments, providing a high-quality solution for the long life and high reliability of automotive electronics, and possesses broad application prospects and market value.

[0036] This patent proposes a new transistor-based step-down circuit that solves many technical challenges of traditional step-down circuits in automotive electronics applications through innovative circuit structure and optimized design. Its key innovations and protection points are mainly concentrated in the following three aspects:

[0037] Efficient and stable voltage regulation mechanism

[0038] This circuit forms a core control node through the conduction of transistor Q2 and the stable voltage (628mV) at the emitter of transistor Q1. Combined with the Darlington circuit formed by transistors Q3 and Q5, it achieves high-precision regulation of the output voltage. When the output voltage fluctuates, the negative feedback mechanism formed by transistor Q1 and the Darlington circuit quickly responds and corrects the circuit state, ensuring that the output voltage remains at a stable 12V. This innovative design effectively avoids the voltage instability caused by load fluctuations in traditional circuits and meets the high-precision voltage requirements of modern automotive electronics.

[0039] Strong load capacity and wide input voltage adaptability range

[0040] This patented circuit operates stably over a wide input voltage range of 16V to 32V and supports output load currents exceeding 5A. This high load capacity significantly enhances the circuit's practicality and adaptability, providing ample energy reserves for high-power scenarios such as MOSFET driving and 12V system power supply. This feature enables the circuit to meet the needs of a wide range of automotive electronic devices, significantly outperforming traditional discrete component circuits and some buck converter solutions.

[0041] Simplified circuit structure and low-cost design

[0042] This circuit uses four transistors to build the core circuit, fully utilizing the characteristics of the transistors. It does not require complex magnetic components or control algorithms, thereby significantly simplifying the circuit structure and reducing material costs and manufacturing complexity. Compared with traditional buck circuits or voltage regulator solutions, this circuit is extremely economical while ensuring high performance, providing a better solution for large-scale applications in automotive electronic systems. The innovation of this patent is mainly reflected in the comprehensive advantages of stability, load capacity and low cost, and is suitable for a variety of application scenarios in modern automotive electronics. By protecting these key designs, this patent can ensure its leading position in the field of buck circuit technology, while also having broad market promotion value.

[0043] First, the circuit utilizes four transistors as its core structure. Through a Darlington circuit consisting of transistors Q3 and Q5 and a negative feedback mechanism via transistor Q1, it achieves high-precision regulation of the output voltage. When the input voltage exceeds the output voltage by 4V, the output voltage remains stable, effectively meeting the high-precision voltage requirements of automotive electronics. This design enables rapid response to voltage changes and suppresses fluctuations, significantly improving the reliability of the power supply system.

[0044] Another major technological breakthrough is the circuit's robust load capacity. Capable of supporting load currents exceeding 5A, it provides stable power for high-power scenarios such as MOSFET drivers and 12V system power supplies. This achievement far surpasses traditional discrete component solutions in load capacity and voltage stability, enhancing the circuit's adaptability and practicality.

[0045] In addition, the circuit has a simple structure and does not require complex magnetic components and control algorithms, which greatly reduces material costs and design difficulty. This achievement fully demonstrates the balance between technological innovation in simplifying design and optimizing performance, and is particularly suitable for mass production and application of automotive electronic systems. The simulated waveform of the voltage from 18V to 32V is as follows Figure 2 .

[0046] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention; therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is limited by the appended claims rather than the above description. Therefore, it is intended that all changes that fall within the meaning and scope of the equivalent elements of the claims are included in the present invention, and any figure signs in the claims should not be regarded as limiting the claims involved.

[0047] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A new step-down circuit for automotive electronics, characterized in that: include: Transistor Q1, transistor Q2, transistor Q3, transistor Q5; The emitter of the transistor Q2 is grounded, the base of the transistor Q2 is connected to one end of the resistor R5 and one end of the resistor R7, the collector of the transistor Q2 is connected to the other end of the resistor R5, one end of the resistor R6, and the emitter of the transistor Q1, and the connection point of the emitter of the transistor Q1, the resistor R5, and the resistor R6 is a node 1; The other end of the resistor R7, the other end of the resistor R6, and the collector of the transistor Q4 are connected to the power supply end; The collector of the transistor Q4 is also connected to one end of the resistor R4 and the collector of the transistor Q5. The other end of the resistor R4 is connected to the collector of the transistor Q1 and the base of the transistor Q3. The connection point of the resistor R4, the collector of the transistor Q1 and the base of the transistor Q3 is a node 2. The emitter of the transistor Q3 is connected to the base of the transistor Q5, and the connection point between the emitter of the transistor Q3 and the base of the transistor Q5 is a node 4; The base of the transistor Q1 is connected to one end of the resistor R13, the other end of the resistor R13 is connected to one end of the resistor R9 and one end of the resistor R8, and the connection point of the resistors R13, R9 and R8 is a node 3, and the other end of the resistor R8 is grounded; The emitter of the transistor Q5 is connected to the other end of the resistor R9, one end of the capacitor C1, and one end of the resistor R2, and the connection point between the emitter of the transistor Q5 and the resistor R9 is node 5. The other end of the capacitor C1 and the other end of the resistor R2 are connected and grounded.

2. The novel step-down circuit for automotive electronics according to claim 1, characterized in that: The transistor Q3 and the transistor Q5 form a Darlington circuit.

3. The novel step-down circuit for automotive electronics according to claim 2, characterized in that: The Darlington circuit and the transistor Q1 form a negative feedback circuit.

4. The novel step-down circuit for automotive electronics according to claim 1, characterized in that: The resistance value of the resistor R2 is 100Ω, the resistance value of the resistor R9 is 161kΩ, the resistance value of the resistor R8 is 10kΩ, the resistance value of the resistor R13 is 1kΩ, the resistance value of the resistor R4 is 100kΩ, the resistance value of the resistor R6 is 100kΩ, the resistance value of the resistor R5 is 100kΩ, and the resistance value of the resistor R7 is 100kΩ.

5. The novel step-down circuit for automotive electronics according to claim 1, characterized in that: The capacity of the capacitor C1 is 10UF.

6. The novel step-down circuit for automotive electronics according to claim 1, characterized in that: The resistor R2 is a variable resistor, and the variable curve type of the resistor R2 potentiometer is an A-type potentiometer.

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