Voltage-stabilizing independent auxiliary power supply circuit

Abstract

The utility model relates to the technical field of charging circuits, and discloses a voltage-stabilizing independent auxiliary power supply circuit which comprises a non-CT transformer T1, a diode D2, an adjustable voltage regulator U1, a diode D3, a resistor R8, a diode D1, a capacitor C8, a capacitor C9, a capacitor C407 and an adjustable resistor RH. After 220V input voltage is applied to the primary side of the non-CT transformer T1, the 220V voltage is reduced to 20-40v through mutual inductance of a primary winding and a secondary winding, meanwhile, the frequency is kept at 50Hz, then half-wave rectification is carried out through a diode D2, an alternating current signal is converted into a ripple direct current signal, and then the ripple direct current signal is input into an adjustable voltage regulator U1. And the current is controlled by an adjustable resistor RH connected with a GND pin of the adjustable voltage regulator U1, and is finally output after being filtered by a capacitor C9, so that stable current output and adjustable voltage output are realized.

Description

Technical Field

[0001] The present application relates to the technical field of charging circuits, and in particular to a voltage-stabilized independent auxiliary power supply circuit. Background Art

[0002] The charger needs a corresponding voltage regulator to stabilize and regulate the input voltage so that the charger can output a stable DC. The existing charger power supply circuit for outputting DC has a complex circuit structure and a fixed output result, and cannot output the corresponding voltage as required. Utility Model Content

[0003] The purpose of the present application is to provide a voltage-stabilized independent auxiliary power supply circuit so that the charger can output a stable direct current and an adjustable voltage.

[0004] To achieve the above-mentioned purpose, the present application discloses the following technical solutions: a voltage-stabilized independent auxiliary power supply circuit, including a non-CT transformer T1, a diode D2, an adjustable voltage regulator U1, a diode D3, a resistor R8, a diode D1, a capacitor C8, a capacitor C9, a capacitor C407, and an adjustable resistor RH;

[0005] One side of the primary winding of the non-CT transformer T1 is connected to a 220V input voltage, the first output pin of one side of the secondary winding of the non-CT transformer T1 is connected to the positive electrode of the diode D2, the negative electrode of the diode D2 is connected to the voltage input end of the adjustable voltage regulator U1, the positive electrode of the capacitor C8, and the negative electrode of the diode D3, the negative electrode of the capacitor C8 is connected to the second output pin of one side of the secondary winding of the non-CT transformer T1, the negative electrode of the capacitor C407, the first fixed pin of the adjustable resistor RH, the moving pin of the adjustable resistor RH, and the negative electrode of the capacitor C9, and the negative electrode of the capacitor C8 is grounded;

[0006] The voltage output end of the adjustable voltage regulator U1 is connected to the first pin of the resistor R8, the cathode of the diode D1, the anode of the capacitor C9, and the anode of the diode D3;

[0007] The second end of the resistor R8 is connected to the anode of the diode D1 and the anode of the capacitor C407;

[0008] The second stator pin of the adjustable resistor RH is connected to the ground pin of the adjustable voltage regulator U1.

[0009] Preferably, the model of the adjustable voltage regulator U1 is LM317.

[0010] Beneficial effect: After the input voltage of 220V is applied to the primary of the non-CT transformer T1, the voltage-stabilized independent auxiliary power supply circuit of the present application steps down the 220V voltage to 20-40V through the mutual inductance of the primary winding and the secondary winding, while maintaining the frequency at 50Hz, and then performs half-wave rectification through the diode D2 to convert the AC signal into a ripple DC signal, which is then input into the adjustable voltage regulator U1 and controlled by the adjustable resistor RH connected to the GND pin of the adjustable voltage regulator U1, and finally output after filtering through the capacitor C9, thereby achieving stable current output and adjustable voltage output. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0012] Figure 1 A circuit schematic diagram of a voltage-stabilized independent auxiliary power supply circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0013] The technical solutions in the embodiments of the present application are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0014] In this article, the term "comprising" is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, the elements defined by the sentence "comprising..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0015] like Figure 1 A voltage-stabilized independent auxiliary power supply circuit is shown, comprising a non-CT transformer T1, a diode D2, an adjustable voltage regulator U1, a diode D3, a resistor R8, a diode D1, a capacitor C8, a capacitor C9, a capacitor C407, and an adjustable resistor RH.

[0016] In this embodiment, the model of the diode D2 is STPS 3150, the model of the adjustable voltage regulator U1 is LM317, the model of the diode D3 is 1N4007, the resistance value of the resistor R8 is 200Ω, the model of the diode D1 is 1N4007, the capacitance value of the capacitor C8 is 1000uF, the capacitance value of the capacitor C9 is 1000uF, the capacitance value of the capacitor C407 is 10uF, and the adjustable resistor RH is W502.

[0017] Specifically, as shown in the figure, the primary winding side of the non-CT transformer T1 is connected to the 220V input voltage, the first output pin of the secondary winding side of the non-CT transformer T1 is connected to the positive electrode of the diode D2, the negative electrode of the diode D2 is connected to the voltage input end of the adjustable voltage regulator U1, the positive electrode of the capacitor C8, and the negative electrode of the diode D3, the negative electrode of the capacitor C8 is connected to the second output pin of the secondary winding side of the non-CT transformer T1, the negative electrode of the capacitor C407, the first fixed pin of the adjustable resistor RH, the moving pin of the adjustable resistor RH, and the negative electrode of the capacitor C9, and the negative electrode of the capacitor C8 is grounded. The voltage output end of the adjustable voltage regulator U1 is connected to the first pin of the resistor R8, the negative electrode of the diode D1, the positive electrode of the capacitor C9, and the positive electrode of the diode D3. The second end of the resistor R8 is connected to the positive electrode of the diode D1 and the positive electrode of the capacitor C407. The second stator pin of the adjustable resistor RH is connected to the ground pin of the adjustable voltage regulator U1.

[0018] Based on the above, the adjustable voltage regulator U1 i.e. LM317 acts as a three-terminal voltage regulator with an output voltage operating range of 1.2v-37v and a maximum load current of up to 1.5A. If a battery or any other voltage source is connected to the output terminals of the adjustable voltage regulator U1, diode D1 and diode D3 are used to protect the adjustable voltage regulator U1 from excessive current flowing through it. Diode D3 protects the capacitor from discharging during an input short circuit, while diode D2 is used to protect capacitor C407 by providing a low impedance discharge path during an output short circuit.

[0019] Working principle: Apply 220V input voltage to the primary of non-CT transformer T1, and step it down to 20-40v through the mutual inductance of the primary winding and the secondary winding, while keeping the frequency at 50Hz. After that, half-wave rectification is performed through diode D2 to convert the AC signal into a ripple DC signal. The rectified voltage then enters the input end of the adjustable voltage regulator U1. The output voltage range of the voltage-stabilized independent auxiliary power supply circuit of this embodiment is controlled by connecting an adjustable resistor RH (also called a potentiometer) to the GND pin of the voltage regulator adjustable voltage regulator U1. Then, the DC signal is output after filtering through a 1000uF electrolytic capacitor. The output current of the voltage-stabilized independent auxiliary power supply circuit of this embodiment is 1.5A, and the voltage is adjustable between 1.2-37V.

[0020] Finally, it should be noted that the above is only a preferred embodiment of the present application and is not intended to limit the present application. Although the present application has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A voltage-stabilized independent auxiliary power supply circuit, It is characterized in that It includes a non-CT transformer T1, a diode D2, an adjustable voltage regulator U1, a diode D3, a resistor R8, a diode D1, a capacitor C8, a capacitor C9, a capacitor C407, and an adjustable resistor RH; One side of the primary winding of the non-CT transformer T1 is connected to a 220V input voltage, the first output pin of one side of the secondary winding of the non-CT transformer T1 is connected to the positive electrode of the diode D2, the negative electrode of the diode D2 is connected to the voltage input end of the adjustable voltage regulator U1, the positive electrode of the capacitor C8, and the negative electrode of the diode D3, the negative electrode of the capacitor C8 is connected to the second output pin of one side of the secondary winding of the non-CT transformer T1, the negative electrode of the capacitor C407, the first fixed pin of the adjustable resistor RH, the moving pin of the adjustable resistor RH, and the negative electrode of the capacitor C9, and the negative electrode of the capacitor C8 is grounded; The voltage output end of the adjustable voltage regulator U1 is connected to the first pin of the resistor R8, the cathode of the diode D1, the anode of the capacitor C9, and the anode of the diode D3; The second end of the resistor R8 is connected to the anode of the diode D1 and the anode of the capacitor C407; The second stator pin of the adjustable resistor RH is connected to the ground pin of the adjustable voltage regulator U1.

2. The voltage-stabilized independent auxiliary power supply circuit according to claim 1, It is characterized in that The model of the adjustable voltage regulator U1 is LM317.

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