Dial switch power supply output voltage control circuit

Abstract

The utility model discloses a dial switch power supply output voltage control circuit which comprises a transformer, an optocoupler, a voltage regulator, a resistor R10, a resistor R11, a resistor R12, a resistor R14, a resistor R15 and a dial switch. A primary side of the transformer is connected with a power supply, a secondary side of the transformer leads out positive voltage V1 and negative voltage V2, the positive voltage V1 is connected to an anode of a light-emitting diode of the optocoupler, a cathode of the light-emitting diode of the optocoupler is connected to a cathode of the voltage regulator, an anode of the voltage regulator is grounded, and a base electrode of the voltage regulator is connected between the resistor R10 and the resistor R11. The resistor R10 and the resistor R11 are connected in series between the positive voltage V1 and the ground; the resistor R12 is connected between the negative voltage V2 and the third pin of the dial switch, the resistor R14 is connected between the second pin of the dial switch and the middle connecting point of the resistor R10 and the resistor R11, and the resistor R15 is connected between the sixth pin of the dial switch and the middle connecting point of the resistor R10 and the resistor R11. According to the utility model, two-path output and three output states can be adjusted, and the circuit is simple and easy to realize.

Description

Technical Field

[0001] The utility model relates to the technical field of a dial switch power supply, in particular to an output voltage control circuit of a dial switch power supply. Background Art

[0002] The flyback dip switch power supply is a simple, efficient and reliable power supply widely used in electronic equipment. The general flyback power supply has only one stable output. If the device needs to output two optional voltages and does not need to output at the same time, the power supply is in standby state without output. The ordinary flyback power supply cannot achieve this function. The switching of a single output dip switch can only make the output voltage in the on or off state, and cannot be in the standby state. Restarting requires extra time requirements. Utility Model Content

[0003] In view of the defects of the prior art, the utility model provides a DIP switch power supply output voltage control circuit which can adjust two-way output and output three states. The circuit is simple and easy to implement.

[0004] In order to solve the technical problem, the technical solution adopted by the utility model is: a dip switch power supply output voltage control circuit, including a transformer T1, an optical coupler U3, a voltage regulator U2, a resistor R10, a resistor R11, a resistor R12, a resistor R14, a resistor R15 and a dip switch K1; the primary side of the transformer T1 is connected to the power supply, the secondary side of the transformer T1 leads to a positive voltage V1 and a negative voltage V2, the positive voltage V1 is connected to the anode of the light emitting diode of the optical coupler U3, the cathode of the light emitting diode of the optical coupler U3 is connected to the cathode of the voltage regulator U2, the anode of the voltage regulator U2 is grounded, and the base of the voltage regulator U2 is connected to the resistor R10 and the resistor R11 , resistor R10 and resistor R11 are connected in series between the positive voltage V1 and the ground; resistor R12 is connected between the negative voltage V2 and the 3rd pin of the dip switch K1, the 3rd pin of the dip switch K1 is connected to the 5th pin, and the 5th pin of the dip switch K1 is connected to the cathode of the light-emitting diode of the optocoupler U3, one end of the resistor R14 is connected to the 2nd pin of the dip switch K1, the other end of the resistor R14 is connected between the resistor R10 and the resistor R11, the 4th pin of the dip switch K1 is connected to the positive voltage V1, one end of the resistor R15 is connected to the 6th pin of the dip switch K1, the other end of the resistor R15 is connected between the resistor R10 and the resistor R11, and the 4th pin and the 6th pin of the dip switch K1 are connected.

[0005] Furthermore, it also includes a diode D4, a diode D5, an electrolytic capacitor EC2, an electrolytic capacitor EC3, and a resistor R2, wherein the anode of the diode D4 is connected to the 8th and 9th pins of the secondary coil of the transformer T1, the cathode of the diode D4 is connected to the positive electrode of the electrolytic capacitor EC2, the negative electrode of the electrolytic capacitor EC2 is connected to the 10th pin of the transformer and the ground, the cathode of the diode D5 is connected to the 11th pin of the transformer, the anode of the diode D5 is connected to the negative electrode of the electrolytic capacitor EC3, the positive electrode of the electrolytic capacitor EC3 is grounded, the resistor R2 is connected between the positive electrode of the electrolytic capacitor EC2 and the ground, a positive voltage V1 is drawn between the positive electrode of the electrolytic capacitor EC2 and the resistor R2, and a negative voltage V2 is drawn between the negative electrode of the electrolytic capacitor EC3 and the anode of the diode D5. The diode D4, the diode D5, the electrolytic capacitor EC2, and the electrolytic capacitor EC3 are used to filter out ripples and rectify.

[0006] Further, the positive voltage V1 is connected to the anode of the light emitting diode of the optocoupler U3 through the diode D6 and the resistor R17, the anode of the diode D6 is connected to the positive voltage V1, the cathode of the diode D6 is connected to one end of the resistor R17, and the other end of the resistor R17 is connected to the anode of the light emitting diode of the optocoupler U3. The diode D6 is used for rectification, and the resistor R17 is used for voltage division.

[0007] Furthermore, a resistor R8 is connected between the anode and cathode of the light emitting diode of the optocoupler U3, and a diode D7 is connected between the cathode of the light emitting diode of the optocoupler U3 and the cathode of the voltage regulator U2, the anode of the diode D7 is connected to the cathode of the light emitting diode of the optocoupler U3, and the cathode of the diode D7 is connected to the cathode of the voltage regulator U2. The diode D7 is used for rectification.

[0008] Furthermore, a capacitor C11 and a resistor R9 are connected between the cathode and the base of the voltage regulator U2.

[0009] Furthermore, the transformer T1 is a flyback dip switch transformer.

[0010] The beneficial effects of the utility model: the utility model only needs one power supply to output three states, namely, output voltage 1, output voltage 2, and standby. There is no output in the standby state, which is convenient for optional use of output. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a circuit schematic diagram of the utility model. DETAILED DESCRIPTION

[0012] The present invention is described in detail below in conjunction with the various embodiments shown in the accompanying drawings, but it should be noted that these embodiments are not limitations of the present invention, and any equivalent transformations or substitutions in functions, methods, or structures made by ordinary technicians in the field based on these embodiments are all within the scope of protection of the present invention.

[0013] The utility model provides an output voltage change control circuit, such as Figure 1 As shown, it includes: transformer T1, diode D4, electrolytic capacitor EC2, resistor R2, electrolytic capacitor EC3, diode D5, diode D6, resistor R17, optocoupler U3, resistor R8, diode R7, voltage regulator U2U2, resistor R10, resistor R11, resistor R12, resistor R14, resistor R15, and dip switch K1.

[0014] The primary side of the transformer T1 is connected to the power supply through a filter rectifier circuit, which is not the innovation of the utility model and will not be described in detail. The anode of the diode D4 is connected to the 8th pin of the secondary coil of the transformer T1, the cathode of D4 is connected to the positive electrode of the electrolytic capacitor EC2, the negative electrode of the electrolytic capacitor EC2 is grounded, the resistor R2 is connected to both ends of the electrolytic capacitor EC2, the cathode of the diode D5 is connected to the 10th pin of the secondary coil T1 of the transformer, the anode of D5 is connected to the negative electrode of the electrolytic capacitor EC3, and the positive electrode of the electrolytic capacitor EC3 is grounded. The anode of diode D6 is connected to the positive electrode of electrolytic capacitor EC2, the cathode of D6 is connected to the anode of light emitting diode of optocoupler U3 through resistor R17, resistor R8 is connected in parallel between the anode and cathode of light emitting diode of optocoupler U3, one end of resistor R10 is connected to the positive electrode of electrolytic capacitor EC2, and the other end is connected to the base of voltage regulator U2, one end of resistor R11 is connected to the base of voltage regulator U2 and the other end is grounded, the anode of diode D7 is connected to the cathode of light emitting diode of optocoupler U3, the anode of D7 is connected to the cathode of voltage regulator U2, resistor R12 is connected to the negative electrode of electrolytic capacitor EC3 and pin 3 of dial switch K1, resistor R14 is connected to pin 2 of dial switch K1 and the base of voltage regulator U2, resistor R15 is connected to pin 6 of dial switch K1 and the base of voltage regulator U2, and pin 4 of dial switch K1 is connected to the positive electrode of electrolytic capacitor EC2. Pin 3 of dial switch K1 is connected to pin 5, and pin 4 of dial switch K1 is connected to pin 6. In this embodiment, a positive voltage V1 is drawn between the positive electrode of the electrolytic capacitor EC2 and the resistor R2, a negative voltage V2 is drawn between the negative electrode of the electrolytic capacitor EC3 and the anode of the diode D5, and a voltage between the resistor R10 and the resistor R11 is used as the output voltage of the switching power supply.

[0015] The process of implementing the output state change in this embodiment is as follows: when the DIP switch K1 is turned to the positions of pins 7 and 8, the resistors R12, R14, and R15 are not connected between R10 and R11, the voltage-dividing resistors of the power supply are R10 and R11, and the output voltage is (V1 / R11)*(R10+R11); when the switch K1 is turned to pins 5 and 6, R15 and R10 are connected in parallel and then in series with R11. Assume that R=R15*R10 / (R15+R10). At this time, the output voltage is (V1 / R11)*(R+R11), which is less than 1V. At the same time, the cathode of the light-emitting diode of the optocoupler U3 is connected to V2, which is a negative voltage. At this time, V1 passes through the diode D6, the resistor R17, and the light-emitting diode of the optocoupler U3 to V2 to form a loop, thereby maintaining the circuit in a low-power standby state. When the switch K1 is turned to pins 1 and 2, Rx = R14*R10 / (R14+R10), and the output voltage changes to (V1 / R11)*(Rx+R11). Through the DIP switch K1, the output can be in a standby state with no output and switch back and forth between two common voltages, and the power supply does not need to be restarted during the switching process.

[0016] In summary, compared with the existing power supply output control circuit, the beneficial effects of the utility model are: the utility model only needs one power supply to output three states, output voltage 1, output voltage 2, and standby. There is no output in the standby state, which is convenient for optional output use.

[0017] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0018] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. The output voltage control circuit of the DIP switch power supply is characterized by: The invention comprises a transformer T1, an optical coupler U3, a voltage regulator U2, a resistor R10, a resistor R11, a resistor R12, a resistor R14, a resistor R15 and a dial switch K1; the primary side of the transformer T1 is connected to a power supply, the secondary side of the transformer T1 leads to a positive voltage V1 and a negative voltage V2, the positive voltage V1 is connected to the anode of the light-emitting diode of the optical coupler U3, the cathode of the light-emitting diode of the optical coupler U3 is connected to the cathode of the voltage regulator U2, the anode of the voltage regulator U2 is grounded, the base of the voltage regulator U2 is connected between the resistor R10 and the resistor R11, the resistor R10 and the resistor R11 are connected in series at the positive voltage V1 and ground; resistor R12 is connected between negative voltage V2 and pin 3 of dip switch K1, pin 3 of dip switch K1 is connected to pin 5, and pin 5 of dip switch K1 is connected to the cathode of the light emitting diode of optocoupler U3, one end of resistor R14 is connected to pin 2 of dip switch K1, the other end of resistor R14 is connected between resistor R10 and resistor R11, pin 4 of dip switch K1 is connected to positive voltage V1, one end of resistor R15 is connected to pin 6 of dip switch K1, the other end of resistor R15 is connected to pin R10 and resistor R11, and pin 4 and pin 6 of dip switch K1 are connected.

2. The DIP switch power supply output voltage control circuit according to claim 1, characterized in that: It also includes a diode D4, a diode D5, an electrolytic capacitor EC2, an electrolytic capacitor EC3, and a resistor R2. The anode of the diode D4 is connected to pins 8 and 9 of the secondary coil of the transformer T1, the cathode of the diode D4 is connected to the positive electrode of the electrolytic capacitor EC2, the negative electrode of the electrolytic capacitor EC2 is connected to pin 10 of the transformer and the ground, the cathode of the diode D5 is connected to pin 11 of the transformer, the anode of the diode D5 is connected to the negative electrode of the electrolytic capacitor EC3, the positive electrode of the electrolytic capacitor EC3 is grounded, the resistor R2 is connected between the positive electrode of the electrolytic capacitor EC2 and the ground, a positive voltage V1 is drawn between the positive electrode of the electrolytic capacitor EC2 and the resistor R2, and a negative voltage V2 is drawn between the negative electrode of the electrolytic capacitor EC3 and the anode of the diode D5.

3. The DIP switch power supply output voltage control circuit according to claim 1, characterized in that: The positive voltage V1 is connected to the anode of the light-emitting diode of the optocoupler U3 through the diode D6 and the resistor R17. The anode of the diode D6 is connected to the positive voltage V1, the cathode of the diode D6 is connected to one end of the resistor R17, and the other end of the resistor R17 is connected to the anode of the light-emitting diode of the optocoupler U3.

4. The DIP switch power supply output voltage control circuit according to claim 1, characterized in that: A resistor R8 is connected between the anode and cathode of the light-emitting diode of the optocoupler U3, and a diode D7 is connected between the cathode of the light-emitting diode of the optocoupler U3 and the cathode of the voltage regulator U2, the anode of the diode D7 is connected to the cathode of the light-emitting diode of the optocoupler U3, and the cathode of the diode D7 is connected to the cathode of the voltage regulator U2.

5. The DIP switch power supply output voltage control circuit according to claim 1, characterized in that: A capacitor C11 and a resistor R9 are connected between the cathode and the base of the voltage regulator U2.

6. The DIP switch power supply output voltage control circuit according to claim 1, characterized in that: Transformer T1 is a flyback dip switch transformer.

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