An adjustable output voltage control circuit

Abstract

The utility model provides a kind of adjustable output voltage control circuit, comprising: boost chip U1, first diode D1, second diode D2, first resistance R1, second resistance R2, third resistance R3;Wherein, the SW port of boost chip is connected with the anode of first diode D1, the cathode of first diode D1 is connected with one end of second resistance R2, the other end of second resistance R2 is connected with the FB port of boost chip;One end of first resistance R1 is connected with the FB port of boost chip, the other end of first resistance R1 is connected with common ground terminal;The anode of second diode D2 is connected with DAC voltage, the cathode of second diode D2 is connected with one end of third resistance R3, the other end of third resistance R3 is connected with the FB port of boost chip.The utility model is based on ordinary boost circuit, add a diode and resistance, and the DAC output voltage of MCU is as control switch, reach the purpose of different voltage output.Electronic components are less used, and the purpose of reducing cost is achieved.

Description

Technical Field

[0001] This utility model relates to the field of voltage control circuit technology, specifically to an adjustable output voltage control circuit. Background Technology

[0002] In circuits, boost circuits are often used to generate the required high voltage from a low voltage. Typical boost circuits use boost chips, paired with different resistors, to output a single voltage. If multiple different voltages are needed, multiple boost circuits are required.

[0003] A typical boost converter circuit outputs a fixed voltage, making it impossible to obtain different voltage outputs using a single boost converter. This results in higher costs for the voltage control circuit. Utility Model Content

[0004] The objective of this utility model is achieved through the following technical solution.

[0005] Specifically, this utility model provides an adjustable output voltage control circuit, including:

[0006] The components include a boost converter chip, a first diode, a second diode, a first resistor, a second resistor, and a third resistor; among which,

[0007] The SW port of the boost chip is connected to the anode of the first diode, the cathode of the first diode is connected to one end of the second resistor, and the other end of the second resistor is connected to the FB port of the boost chip.

[0008] One end of the first resistor is connected to the FB port of the boost chip, and the other end of the first resistor is connected to the common ground terminal;

[0009] The anode of the second diode is connected to the DAC voltage, the cathode of the second diode is connected to one end of the third resistor, and the other end of the third resistor is connected to the FB port of the boost chip.

[0010] Furthermore, a first inductor is connected between the VIN terminal and the SW terminal of the boost chip.

[0011] Furthermore, a fifth resistor is connected between the EN terminal of the boost chip and the input voltage.

[0012] Furthermore, a first capacitor is connected in parallel across the two ends of the second resistor.

[0013] Furthermore, the adjustable output voltage control circuit further includes a fourth capacitor, one end of which is connected to the cathode of the first diode, and the other end of which is connected to a common ground terminal.

[0014] Furthermore, the adjustable output voltage control circuit further includes a fourth resistor and a sixth resistor. One end of the sixth resistor is connected to the cathode of the first diode, and the other end is connected to the voltage output terminal. One end of the fourth resistor is connected to the voltage output terminal, and the other end is connected to the common ground terminal.

[0015] Furthermore, the adjustable output voltage control circuit further includes a second capacitor and a third capacitor connected in parallel between the input voltage and the common ground terminal.

[0016] Furthermore, the adjustable output voltage control circuit further includes a Zener diode connected between the voltage output terminal and the common ground terminal.

[0017] The advantages of this invention are: by adding a diode and a resistor to a conventional boost circuit, and using the MCU's DAC output voltage as a control switch, different voltage outputs can be achieved. This reduces the number of electronic components used, thus lowering costs. Attached Figure Description

[0018] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0019] Appendix Figure 1 A circuit diagram of an adjustable output voltage control according to an embodiment of the present invention is shown. Detailed Implementation

[0020] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0021] According to an embodiment of this utility model, an adjustable output voltage control circuit is proposed, comprising:

[0022] The components include a boost converter chip U1, a first diode D1, a second diode D2, a first resistor R1, a second resistor R2, and a third resistor R3; among which,

[0023] The SW port of the boost chip is connected to the anode of the first diode D1, the cathode of the first diode D1 is connected to one end of the second resistor R2, and the other end of the second resistor R2 is connected to the FB port of the boost chip.

[0024] One end of the first resistor R1 is connected to the FB port of the boost chip, and the other end of the first resistor R1 is connected to the common ground terminal;

[0025] The anode of the second diode D2 is connected to the DAC voltage, and the cathode of the second diode D2 is connected to one end of the third resistor R3. The other end of the third resistor R3 is connected to the FB port of the boost chip.

[0026] A first inductor L1 is further connected between the VIN terminal and the SW terminal of the boost chip.

[0027] A fifth resistor R5 is connected between the EN terminal of the boost chip and the input voltage Vin.

[0028] A first capacitor C1 is further connected in parallel across the two ends of the second resistor R2.

[0029] The adjustable output voltage control circuit further includes a fourth capacitor C4, one end of which is connected to the cathode of the first diode D1, and the other end is connected to a common ground terminal.

[0030] The adjustable output voltage control circuit further includes a fourth resistor R4 and a sixth resistor R6. One end of the sixth resistor is connected to the cathode of the first diode D1, and the other end is connected to the voltage output terminal Vout. One end of the fourth resistor is connected to the voltage output terminal, and the other end is connected to the common ground terminal.

[0031] The adjustable output voltage control circuit further includes a second capacitor C2 and a third capacitor C3 connected in parallel between the input voltage and the common ground terminal.

[0032] PB12 connects to the MCU's DAC (Digital Analog Converter) and is controlled by a 0-3V voltage, allowing Vout to be adjusted between 0-36V.

[0033] U1 is a boost converter chip.

[0034] Vin is the input voltage (2.5V-5.5V) of the boost converter chip.

[0035] VG is the voltage provided by the MCU DAC.

[0036] D2 is a Schottky diode with a voltage drop of 0.5V.

[0037] C2, C3, C1, and C4 are filter capacitors.

[0038] TVS1 is a Zener diode connected between Vout and the common ground terminal.

[0039] I3 is the current flowing through R3, I2 is the current flowing through R2, and I1 is the current flowing through R1.

[0040] I3=(VG-VD-VFB) / R3

[0041] I2=(Vout-VFB) / R2

[0042] I1 = VFB / R1

[0043] VD is the forward voltage of the selected diode D2. This circuit uses a 0.4V forward diode. VFB is the feedback voltage of pin FB of U1. Different voltage values ​​are selected according to different models, such as 0.1 / 0.2 / 0.25 / 0.3 / 0.6V / 1.23V, etc.

[0044] When VG <= VFB + VD, I3 = 0A, Vout = VFB * (1 + R2 / R1).

[0045] When VG>VFB+VD

[0046] According to I3 + I2 = I1, we get

[0047] (VG-VFB-VD) / R3+(Vout-VFB) / R2=VFB / R1

[0048] That is: Vout = VFB * (1 + R2 / R1) - (VG - VFB - VD) * R2 / R3.

[0049] This invention adds a diode and a resistor to a conventional boost circuit, using the MCU's DAC output voltage as a control switch to achieve different voltage outputs. It uses fewer electronic components, thus reducing costs.

[0050] The above description is merely a preferred embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. An adjustable output voltage control circuit, characterized in that, include: The components include a boost converter chip, a first diode, a second diode, a first resistor, a second resistor, and a third resistor; among which, The SW port of the boost chip is connected to the anode of the first diode, the cathode of the first diode is connected to one end of the second resistor, and the other end of the second resistor is connected to the FB port of the boost chip. One end of the first resistor is connected to the FB port of the boost chip, and the other end of the first resistor is connected to the common ground terminal; The anode of the second diode is connected to the DAC voltage, the cathode of the second diode is connected to one end of the third resistor, and the other end of the third resistor is connected to the FB port of the boost chip.

2. The adjustable output voltage control circuit according to claim 1, characterized in that, A first inductor is further connected between the VIN and SW terminals of the boost chip.

3. The adjustable output voltage control circuit according to claim 1, characterized in that, A fifth resistor is connected between the EN terminal of the boost chip and the input voltage.

4. The adjustable output voltage control circuit according to claim 1, characterized in that, A first capacitor is further connected in parallel across the two ends of the second resistor.

5. The adjustable output voltage control circuit according to claim 1, characterized in that, The adjustable output voltage control circuit further includes a fourth capacitor, one end of which is connected to the cathode of the first diode, and the other end of which is connected to a common ground terminal.

6. The adjustable output voltage control circuit according to claim 1, characterized in that, The adjustable output voltage control circuit further includes a fourth resistor and a sixth resistor. One end of the sixth resistor is connected to the cathode of the first diode, and the other end is connected to the voltage output terminal. One end of the fourth resistor is connected to the voltage output terminal, and the other end is connected to the common ground terminal.

7. The adjustable output voltage control circuit according to claim 3, characterized in that, The adjustable output voltage control circuit further includes a second capacitor and a third capacitor connected in parallel between the input voltage and the common ground terminal.

8. The adjustable output voltage control circuit according to claim 6, characterized in that, The adjustable output voltage control circuit further includes a Zener diode connected between the voltage output terminal and the common ground terminal.

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