Reference voltage source circuit, PCB and controller thereof

Abstract

The invention discloses a reference voltage source circuit, a PCB and a controller of the PCB. The reference voltage source circuit comprises a voltage stabilizing unit, a current control unit, a voltage dividing unit, a negative feedback voltage stabilizing unit and a temperature compensation unit. The voltage stabilizing unit is connected with the input ends of the current control unit and the temperature compensation unit, the voltage dividing unit is connected with the output end of the current control unit and the input end of the negative feedback voltage stabilizing unit, and the output end of the negative feedback voltage stabilizing unit is used for outputting reference voltage; the voltage stabilization unit is used for carrying out voltage stabilization processing on the input voltage so as to output reference voltage; the current control unit is used for outputting reference current according to the reference voltage; the negative feedback voltage stabilizing unit is used for performing bias correction on the reference voltage according to the feedback voltage acquired by the voltage dividing unit; the temperature compensation unit is used for offsetting a temperature drift signal of the negative feedback voltage stabilization unit; reliability of the circuit under different working conditions is improved through negative feedback and temperature compensation, output voltage is adjusted in real time through negative feedback, and stable operation under different temperatures is ensured through temperature compensation.

Description

Technical Field

[0001] This invention relates to the field of reference voltage source technology, and in particular to a reference voltage source circuit, PCB board and controller thereof. Background Technology

[0002] In driver circuit applications, the reference voltage plays a crucial role in circuit stability. Currently, commonly used reference voltage sources include Zener diode reference voltage sources and bandgap reference voltage sources. Zener diode reference voltage sources are susceptible to the influence of component parameters, leading to increased reference voltage fluctuations. This is mainly due to the large temperature coefficient of the components used with them; as the temperature rises, the resistance value changes, thus altering the voltage division ratio. Simultaneously, the transistor parameters and resistance values ​​also drift with temperature. While bandgap reference sources provide a high-precision voltage reference, their overall structure is more complex, requiring extremely strict requirements on the transistor layout during the layout design phase.

[0003] It is evident that existing technologies still need improvement and enhancement. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a reference voltage source circuit that introduces a negative feedback mechanism, so that the overall gain mainly depends on the feedback network, reduces the dependence of the gain on the gain of the internal amplification components, and improves the stability of the reference voltage.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A reference voltage source circuit includes a voltage regulator unit, a current control unit, a voltage divider unit, a negative feedback voltage regulator unit, and a temperature compensation unit. The voltage regulator unit is connected to the input terminals of the current control unit and the temperature compensation unit. The voltage divider unit is connected to the output terminal of the current control unit and the input terminal of the negative feedback voltage regulator unit. The output terminal of the negative feedback voltage regulator unit is used to output a reference voltage. The voltage regulator unit is used to regulate the input voltage to output a reference voltage. The current control unit is used to output a reference current based on the reference voltage. The negative feedback voltage regulator unit is used to bias and correct the reference voltage based on the feedback voltage collected by the voltage divider unit. The temperature compensation unit is used to cancel the temperature drift signal of the negative feedback voltage regulator unit.

[0006] In the reference voltage source circuit, the voltage regulation unit includes a first transistor Q1 and a voltage input terminal VCC. The voltage input terminal VCC is connected to the collector of the first transistor Q1, the input terminal of the current control unit, and the input terminal of the negative feedback voltage regulation unit. The collector and base of the first transistor Q1 are both connected to the input terminal of the current control unit, and the emitter of the first transistor Q1 is connected to the temperature compensation unit.

[0007] In the reference voltage source circuit, the voltage regulation unit further includes a third resistor R3. One end of the third resistor R3 is connected to the voltage input terminal VCC, and the other end of the third resistor R3 is connected to the collector of the first transistor Q1.

[0008] In the reference voltage source circuit, the current control unit includes a second transistor Q2. The base of the second transistor Q2 is connected to the base and collector of the first transistor Q1. The collector of the second transistor Q2 is connected to the voltage input terminal VCC. The emitter of the second transistor Q2 is connected to the voltage divider unit.

[0009] In the reference voltage source circuit, the voltage divider unit includes a first resistor R1 and a second resistor R2. One end of the first resistor R1 is connected to the emitter of the second transistor Q2, and the other end of the first resistor R1 is connected to one end of the second resistor R2 and the input terminal of the negative feedback voltage regulator unit. The other end of the second resistor R2 is grounded.

[0010] In the aforementioned reference voltage source circuit, the negative feedback voltage regulation unit includes a third transistor Q3 and a reference voltage output terminal VREG. The base of the third transistor Q3 is connected to the connection node of the first resistor R1 and the second resistor R2. The collector of the third transistor Q3 is connected to the voltage input terminal VCC. The emitter of the third transistor Q3 is connected to the reference voltage output terminal VREG.

[0011] In the reference voltage source circuit, the negative feedback voltage regulation unit further includes a first capacitor C1, one end of which is connected to the emitter of the third transistor Q3, and the other end of which is grounded.

[0012] In the reference voltage source circuit, the temperature compensation unit includes a first diode D1, the negative terminal of the first diode D1 is connected to the emitter of the first transistor Q1, and the positive terminal of the first diode D1 is grounded.

[0013] This application also provides a PCB board printed with the reference voltage source circuit described above.

[0014] This application also provides a controller that uses the reference voltage source circuit described above for operation control.

[0015] Beneficial effects: This invention provides a reference voltage source circuit that utilizes a dual voltage regulation system—a voltage regulator unit and a negative feedback voltage regulator unit—to reduce the impact of input voltage fluctuations and load changes on the output reference voltage. The voltage regulator unit initially stabilizes the input voltage, while the negative feedback voltage regulator unit adjusts in real time to eliminate residual fluctuations. A temperature compensation unit counteracts the effects of temperature changes on the output voltage, introducing temperature compensation components to offset transistor and resistor parameter drift, ensuring stable output voltage over a wide temperature range. A voltage divider unit and a negative feedback voltage regulator unit ensure precise consistency of the output reference voltage. Through negative feedback and temperature compensation, the circuit's reliability and long-term stability under different operating conditions are improved. Negative feedback adjusts the output voltage in real time, while temperature compensation ensures stable operation at different temperatures. Compared to traditional bandgap reference voltage sources, this circuit has a simplified structure, reduces layout design complexity, optimizes the design to reduce the number and complexity of components, and maintains high performance. Attached Figure Description

[0016] Figure 1 A circuit block diagram of the reference voltage source circuit provided by the present invention; Figure 2 A circuit diagram of the reference voltage source circuit provided by the present invention; Figure 3 This is a circuit diagram of an existing reference voltage power supply circuit.

[0017] Explanation of key component symbols: 1-Voltage regulator unit, 2-Current control unit, 3-Voltage divider unit, 4-Negative feedback voltage regulator unit, 5-Temperature compensation unit. Detailed Implementation

[0018] This invention provides a reference voltage source circuit, a PCB board, and a controller thereof. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention.

[0019] In the description of this invention, it should be understood that the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated.

[0020] like Figure 3The circuit shown is a common reference voltage source circuit in the prior art, which mainly uses resistors R1, R2, R3, and R4 to achieve voltage division output. However, because resistors R1, R2, R3, and R4 are affected by temperature changes and temperature coefficients, they are prone to affecting the voltage division ratio, thus causing a certain degree of fluctuation in the reference voltage. Furthermore, changes in the load current will alter the voltage at other nodes in the circuit, thereby affecting the operating state of the first transistor Q1 and the voltage division effect of each resistor, also causing reference voltage fluctuations.

[0021] In a circuit system, the core function of the reference voltage is to provide a stable and accurate voltage reference for internal analog functional modules (such as differential amplifiers, comparators, and current mirrors), ensuring that these modules can accurately amplify, compare, or regulate signals under a unified voltage reference condition. In a drive circuit, if the reference voltage is too high, the drive voltage will exceed the gate withstand voltage limit of the power device, potentially causing the gate oxide layer to burn out and directly damaging the power device. If the reference voltage is too low, it will result in insufficient drive capability. Therefore, in a protection circuit, the reference voltage serves as the reference for the protection threshold. If its value is too high, it will cause the protection circuit to trigger falsely; if its value is too low, the protection circuit may fail to operate when the circuit exceeds the safe range.

[0022] Therefore, the stability of the reference voltage determines whether the subsequent drive circuit can work stably. Please see Figures 1 to 2 This invention provides a reference voltage source circuit, including a voltage regulator unit 1, a current control unit 2, a voltage divider unit 3, a negative feedback voltage regulator unit 4, and a temperature compensation unit 5. The voltage regulator unit 1 is connected to the input terminals of the current control unit 2 and the temperature compensation unit 5. The voltage divider unit 3 is connected to the output terminal of the current control unit 2 and the input terminal of the negative feedback voltage regulator unit 4. The output terminal of the negative feedback voltage regulator unit 4 is used to output a reference voltage. The voltage regulator unit 1 is used to regulate the input voltage to output a reference voltage. The current control unit 2 is used to output a reference current based on the reference voltage. The negative feedback voltage regulator unit 4 is used to bias and correct the reference voltage based on the feedback voltage collected by the voltage divider unit 3. The temperature compensation unit 5 is used to cancel the temperature drift signal of the negative feedback voltage regulator unit 4.

[0023] In this embodiment, the dual voltage regulation mechanism of voltage regulator unit 1 and negative feedback voltage regulator unit 4 significantly reduces the impact of input voltage fluctuations and load changes on the output reference voltage. Voltage regulator unit 1 initially stabilizes the input voltage, while negative feedback voltage regulator unit 4 further eliminates any remaining voltage fluctuations through real-time adjustment. Temperature compensation unit 5 effectively counteracts the impact of temperature changes on the output voltage, ensuring the stability of the output voltage over a wide temperature range. By introducing temperature compensation components, parameter drift caused by temperature changes in transistors and resistors is offset. Voltage divider unit 3 and negative feedback voltage regulator unit 4 ensure the accuracy and consistency of the output reference voltage. Through the negative feedback mechanism and temperature compensation, the reliability and long-term stability of the circuit under different operating conditions are improved. The negative feedback mechanism adjusts the output voltage in real time, and temperature compensation unit 5 ensures stable operation at different temperatures, thereby improving overall reliability. Compared with traditional bandgap reference voltage sources, this circuit structure is simpler, reducing the complexity of layout design. By optimizing the circuit design, the number and complexity of required components are reduced while maintaining high performance.

[0024] The working principle of this application is as follows: When the output voltage (i.e., the reference voltage VREG) increases, the sampling point voltage of voltage divider unit 3 increases, and the overall current of current control unit 2 increases. The increase in current of current control unit 2 will cause the voltage division of voltage regulator unit 1 to increase, thereby reducing the output voltage and playing a reverse regulation role.

[0025] When the output voltage decreases, the sampling point voltage of voltage divider unit 3 decreases, and the overall current of current control unit 2 decreases. The decrease in current of current control unit 2 will reduce the voltage division of voltage regulator unit 1, thereby increasing the output voltage and playing a reverse regulation role.

[0026] The gain of the reference voltage VREG fluctuates due to variations in component parameters. However, the negative feedback mechanism ensures that the overall gain primarily depends on the feedback network, reducing its reliance on the gain of internal amplification components. Even with changes in component parameters, the output voltage remains stable, ensuring the reference voltage's performance is stable and reliable.

[0027] like Figures 1 to 2 As shown, the voltage regulator unit 1 further includes a first transistor Q1 and a voltage input terminal VCC. The voltage input terminal VCC is connected to the collector of the first transistor Q1, the input terminal of the current control unit 2, and the input terminal of the negative feedback voltage regulator unit 4. The collector and base of the first transistor Q1 are both connected to the input terminal of the current control unit 2, and the emitter of the first transistor Q1 is connected to the temperature compensation unit 5.

[0028] In this embodiment, after the first transistor Q1 is connected to the voltage input terminal VCC, it utilizes the characteristic that the base-emitter voltage VBE≈0.7V to provide a stable voltage reference for the current control unit 2. At the same time, it cooperates with the current control unit 2 to form a matching current. When the first transistor Q1 is working in the critical state of the amplification region, its VBE voltage is stable at around 0.7V, providing the most basic and stable voltage and current reference for the subsequent circuit.

[0029] like Figures 1 to 2 As shown, the voltage regulator unit 1 further includes a third resistor R3. One end of the third resistor R3 is connected to the voltage input terminal VCC, and the other end of the third resistor R3 is connected to the collector of the first transistor Q1. By setting the third resistor R3, the overcurrent problem of the current control unit 2 is prevented. The resistance value of the third resistor R3 determines the output current of the current control unit 2.

[0030] like Figures 1 to 2 As shown, the current control unit 2 further includes a second transistor Q2. The base of the second transistor Q2 is connected to the base and collector of the first transistor Q1. The collector of the second transistor Q2 is connected to the voltage input terminal VCC. The emitter of the second transistor Q2 is connected to the voltage divider unit 3. The second transistor Q2 acts as a current control transistor for the current source. It works with the first transistor Q1 and the third resistor R3 to provide a stable reference current for the voltage divider unit 3. The voltage at the power input terminal VCC, after passing through the third resistor R3, provides a collector current to the second transistor Q2. The emitter current of the second transistor Q2 is controlled by the VBE voltage of the first transistor Q1. At this time, the collector current is approximately equal to the emitter current, achieving high-precision current replication, thereby keeping the current flowing into the voltage divider unit 3 stable.

[0031] like Figures 1 to 2 As shown, the voltage divider unit 3 further includes a first resistor R1 and a second resistor R2. One end of the first resistor R1 is connected to the emitter of the second transistor Q2, and the other end of the first resistor R1 is connected to one end of the second resistor R2 and the input terminal of the negative feedback voltage regulator unit 4. The other end of the second resistor R2 is grounded. The first resistor R1 and the second resistor R2 form a voltage divider circuit, which converts the current provided by the second transistor Q2 into a voltage signal and uses this voltage divider signal as the bias voltage of the negative feedback voltage regulator unit 4 to control the conduction degree of the negative feedback voltage regulator unit 4. When the stable current output by the second transistor Q2 passes through the first resistor R1 and the second resistor R2, a voltage divider V = I × (R1 + R2) is generated on the first resistor R1 and the second resistor R2. This voltage divider determines the input potential of the negative feedback voltage regulator unit 4, and thus the output voltage of the negative feedback voltage regulator unit 4.

[0032] like Figures 1 to 2 As shown, the negative feedback voltage regulator unit 4 further includes a third transistor Q3 and a reference voltage output terminal VREG. The base of the third transistor Q3 is connected to the connection node of the first resistor R1 and the second resistor R2. The collector of the third transistor Q3 is connected to the voltage input terminal VCC, and the emitter of the third transistor Q3 is connected to the reference voltage output terminal VREG. The third transistor Q3 acts as an adjustment transistor. The voltage obtained by the voltage division of the first resistor R1 and the second resistor R2 is input to the base of the third transistor Q3 to adjust the magnitude of its emitter output voltage, which is then supplied to the external drive circuit through the reference voltage output terminal VREG. The third transistor Q3 operates in the linear amplification region, and its base voltage determines its emitter-base voltage VBE3. Therefore, the output voltage VREG is stabilized through the relationship VREG = Vbase + VBE3.

[0033] In this embodiment, the first transistor Q1 is an NPN transistor, and the second transistor Q2 and the third transistor Q3 are both PNP transistors.

[0034] like Figures 1 to 2 As shown, the negative feedback voltage regulation unit 4 further includes a first capacitor C1. One end of the first capacitor C1 is connected to the emitter of the third transistor Q3, and the other end of the first capacitor C1 is grounded. The first capacitor C1 is used to filter out the voltage ripple of the output voltage (i.e., the reference voltage) of the emitter of the third transistor Q3, which effectively improves the smoothness and stability of the output voltage, and at the same time enhances the transient response of the circuit (quickly provides absorption current and suppresses voltage fluctuations when the load changes suddenly).

[0035] like Figures 1 to 2 As shown, the temperature compensation unit 5 further includes a first diode D1, the cathode of which is connected to the emitter of the first transistor Q1, and the anode of which is grounded. Temperature compensation is achieved using the first diode D1 to counteract the temperature drift of the VBE voltage of the first transistor Q1, thereby improving the temperature stability of the reference voltage.

[0036] The principle is as follows: the VBE voltage of a transistor has a negative temperature coefficient; and the forward conduction voltage of a diode also has a negative temperature coefficient. Therefore, the voltage change of the first diode D1 can compensate for the voltage change of the third transistor Q3 VBE3, making the reference voltage less affected by temperature.

[0037] The overall working principle of this application is as follows: The first transistor Q1 provides a stable VBE reference voltage. The second transistor Q2, in conjunction with the third resistor R3, generates a stable reference current. This reference current flows through the first resistor R1 and the second resistor R2, where it is divided to provide the base bias voltage for the third transistor Q3. The third transistor Q3 acts as a regulating transistor, stabilizing the output reference voltage based on the base bias voltage. Simultaneously, the first diode D1 compensates for temperature drift, and the first capacitor C1 filters out the ripple of the reference voltage. Ultimately, this provides the load with a stable power supply characterized by low ripple and good temperature characteristics.

[0038] This application also provides a PCB board printed with the reference voltage source circuit described above.

[0039] This application also provides a controller that uses the reference voltage source circuit described above for operation control.

[0040] In summary, the dual voltage regulation mechanism of voltage regulator unit 1 and negative feedback voltage regulator unit 4 significantly reduces the impact of input voltage fluctuations and load changes on the output reference voltage. Voltage regulator unit 1 initially stabilizes the input voltage, while negative feedback voltage regulator unit 4 further eliminates any residual voltage fluctuations through real-time adjustment. Temperature compensation unit 5 effectively counteracts the effects of temperature changes on the output voltage, ensuring output voltage stability over a wide temperature range. By introducing temperature compensation components, parameter drift caused by temperature changes in transistors and resistors is offset. Voltage divider unit 3 and negative feedback voltage regulator unit 4 ensure the accuracy and consistency of the output reference voltage. Through the negative feedback mechanism and temperature compensation, the reliability and long-term stability of the circuit under different operating conditions are improved. The negative feedback mechanism adjusts the output voltage in real time, and temperature compensation unit 5 ensures stable operation under different temperature environments, thereby improving overall reliability. Compared to traditional bandgap reference voltage sources, this circuit structure is more streamlined, reducing the complexity of layout design. By optimizing the circuit design, the number and complexity of required components are reduced while maintaining high performance.

[0041] It is understood that those skilled in the art can make equivalent substitutions or modifications to the technical solution and inventive concept of the present invention, and all such substitutions or modifications should fall within the protection scope of the appended claims.

Claims

1. A reference voltage source circuit, characterized by comprising: The reference voltage source circuit comprises a voltage stabilizing unit, a current control unit, a voltage dividing unit, a negative feedback voltage stabilizing unit and a temperature compensation unit; the voltage stabilizing unit is connected with the input end of the current control unit and the temperature compensation unit; the voltage dividing unit is connected with the output end of the current control unit and the input end of the negative feedback voltage stabilizing unit; the output end of the negative feedback voltage stabilizing unit is used for outputting a reference voltage; the voltage stabilizing unit is used for stabilizing the input voltage to output a reference voltage; The current control unit is used for outputting a reference current according to the reference voltage; the negative feedback voltage stabilizing unit is used for biasing and correcting the reference voltage according to the feedback voltage collected by the voltage dividing unit; and the temperature compensation unit is used for offsetting the temperature drift signal of the negative feedback voltage stabilizing unit.

2. The reference voltage source circuit of claim 1, wherein, The voltage stabilizing unit comprises a first triode Q1 and a voltage input end VCC; the voltage input end VCC is connected with the collector of the first triode Q1, the input end of the current control unit and the input end of the negative feedback voltage stabilizing unit; the collector and the base of the first triode Q1 are connected with the input end of the current control unit; and the emitter of the first triode Q1 is connected with the temperature compensation unit.

3. The reference voltage source circuit of claim 2, wherein The voltage stabilizing unit further comprises a third resistor R3; one end of the third resistor R3 is connected with the voltage input end VCC; and the other end of the third resistor R3 is connected with the collector of the first triode Q1.

4. The reference voltage source circuit of claim 2, wherein, The current control unit comprises a second triode Q2; the base of the second triode Q2 is connected with the base and the collector of the first triode Q1; the collector of the second triode Q2 is connected with the voltage input end VCC; and the emitter of the second triode Q2 is connected with the voltage dividing unit.

5. The reference voltage source circuit of claim 4, wherein, The voltage dividing unit comprises a first resistor R1 and a second resistor R2; one end of the first resistor R1 is connected with the emitter of the second triode Q2; the other end of the first resistor R1 is connected with one end of the second resistor R2 and the input end of the negative feedback voltage stabilizing unit; and the other end of the second resistor R2 is grounded.

6. The reference voltage source circuit of claim 5, wherein, The negative feedback voltage stabilizing unit comprises a third triode Q3 and a reference voltage output end VREG; the base of the third triode Q3 is connected with the connection node of the first resistor R1 and the second resistor R2; the collector of the third triode Q3 is connected with the voltage input end VCC; and the emitter of the third triode Q3 is connected with the reference voltage output end VREG.

7. The reference voltage source circuit of claim 6, wherein, The negative feedback voltage stabilizing unit further comprises a first capacitor C1; one end of the first capacitor C1 is connected with the emitter of the third triode Q3; and the other end of the first capacitor C1 is grounded.

8. The reference voltage source circuit of claim 2, wherein, The temperature compensation unit comprises a first diode D1; the negative electrode of the first diode D1 is connected with the emitter of the first triode Q1; and the positive electrode of the first diode D1 is grounded.

9. A PCB board characterized by, The PCB is printed with the reference voltage source circuit as claimed in any one of claims 1-8.

10. A controller characterized by comprising: The controller is controlled by the reference voltage source circuit as claimed in any one of claims 1-8.

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