A driving power supply with auxiliary output loop

Abstract

The application discloses a driving power supply with an auxiliary output loop, and is applied to the field of power supply control. The adjusting tube and the sampling resistor are connected in series in the auxiliary output loop, the first control module is connected with the sampling resistor and the switching tube, the switching tube is connected in parallel with the load resistor after being connected in series, and the load resistor is connected in parallel with the main output loop; the second control module is connected with the sampling resistor and the adjusting tube, and the feedback circuit is connected with the control end of the main circuit with the primary winding corresponding to the main output loop and the auxiliary output loop. When the auxiliary output loop is loaded and the main output loop is in the no-load state or the light-load state, the second control module controls the impedance of the adjusting tube to increase, the first control module controls the switching tube to be turned on so that the load resistor is connected to the main output loop, and the two control modules are simultaneously adjusted, so that the problem that the auxiliary output loop cannot normally carry the load under certain conditions is solved. Meanwhile, the impedance of the adjusting tube is adjusted, the output power of the auxiliary output loop is rapidly reduced or cut off, and the abnormal state of the driving power supply in the adjusting process is avoided.

Description

Technical Field

[0001] This application relates to the field of power supply control, and in particular to a drive power supply with an auxiliary output circuit. Background Technology

[0002] In existing power supplies, the main circuit has an output line to supply power to the load; therefore, its output circuit is called the "main output circuit." In addition to the main output circuit, power supplies also have auxiliary output circuits, such as an auxiliary power supply. These output circuits, via positive and negative wires, provide a stable low-voltage output (e.g., 12V) to the user for connecting external devices. This auxiliary output circuit is typically coupled to components such as transformers in the main circuit to obtain input power.

[0003] If the main output circuit is unloaded or lightly loaded when the auxiliary output circuit is loaded, the main circuit cannot provide sufficient power to the auxiliary output circuit. This will cause the main circuit to be unable to output power at that moment, leading to circuit instability and malfunction. To solve this problem, a dummy load is usually set in the main output circuit. However, if the dummy load is always connected, it will consume a lot of power. Therefore, most dummy load circuits use a switch to control whether they are connected to the main output circuit. When a sudden loading of the auxiliary output circuit is detected, and the dummy load is connected by switching the switch on and off, the output of the feedback circuit connected to the main output circuit changes, controlling the power transmitted by the main circuit to increase. This increases the power received by the auxiliary output circuit, satisfying the output power requirements of the auxiliary output circuit.

[0004] However, when the dummy load is connected, the feedback circuit is prone to slow adjustment. Before the main circuit increases the transmitted power, the voltage of the main output circuit and the auxiliary output circuit drops by a large amplitude instantaneously, which leads to the circuit not being able to adjust to a steady state.

[0005] In view of the above-mentioned technology, finding a driving power supply for the auxiliary output circuit that can meet the requirements is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] The purpose of this application is to provide a drive power supply with an auxiliary output circuit, which can promptly adjust the unstable state of the circuit.

[0007] To solve the above-mentioned technical problems, this application provides a drive power supply with an auxiliary output circuit, including a main output circuit, an auxiliary output circuit, a first control module, a load resistor, a switching transistor and a feedback circuit, and further including: a second control module, an adjustment transistor and a sampling resistor;

[0008] The regulating tube is connected in series in the auxiliary output circuit;

[0009] A sampling resistor is connected in series in the auxiliary output circuit to sample the output current of the auxiliary output circuit and obtain the current sample value.

[0010] The input terminal of the first control module is connected to the sampling resistor, and the output terminal of the first control module is connected to the control terminal of the switching transistor, which is used to control the switching transistor to turn on and off according to the current sampling value.

[0011] The switching transistor is connected in series with the load resistor and then in parallel with the output terminal of the main output circuit;

[0012] The input terminal of the second control module is connected to the sampling resistor, and the output terminal of the second control module is connected to the control terminal of the adjustment tube, so as to adjust the impedance of the adjustment tube according to the current sampling value.

[0013] The input terminal of the feedback circuit is connected to the output terminal of the main output circuit to detect the current or voltage of the main output circuit and obtain the detection value. The output terminal of the feedback circuit is connected to the control terminal of the main circuit containing the primary winding in the auxiliary output circuit to adjust the power transmitted by the main circuit based on the comparison between the detection value and the reference parameter.

[0014] Preferably, the feedback circuit includes a control chip, a first loop, and a first preset signal source;

[0015] The input terminal of the first loop is connected to the main output loop, the base terminal of the first loop is connected to the first preset signal source, and the output terminal of the first loop is connected to the input terminal of the control chip.

[0016] The output terminal of the control chip is connected to the control terminal of the main circuit containing the primary winding.

[0017] Preferably, the first loop is a first PID controller, including a first operational amplifier, a first capacitor, and a first resistor.

[0018] Preferably, the first control module includes a first comparator and a second preset signal source;

[0019] The negative input terminal of the first comparator is connected to the sampling resistor, the positive input terminal of the first comparator is connected to the second preset signal source, and the output terminal of the second comparator is connected to the control terminal of the switching transistor.

[0020] Preferably, the regulating transistor is a first transistor;

[0021] The first transistor is an NPN transistor;

[0022] The second control module includes a second resistor, a third resistor, a second capacitor, and a third capacitor;

[0023] The first end of the second resistor is connected to the collector of the first transistor, and the second end of the second resistor is connected to the base of the first transistor.

[0024] The first end of the third resistor is connected to the second end of the second resistor and the base of the first transistor; the second end of the third resistor is connected to the second end of the sampling resistor.

[0025] The first terminal of the second capacitor is connected to the first terminal of the second resistor, and the second terminal of the second capacitor is connected to the second terminal of the sampling resistor and the second terminal of the third resistor.

[0026] The first terminal of the third capacitor is connected to the emitter of the first transistor, and the second terminal of the third capacitor is connected to the second terminal of the second sampling resistor, the second terminal of the second capacitor, and the second terminal of the third resistor.

[0027] Preferably, the second control module further includes a second comparator and a third preset signal source;

[0028] The negative input of the second comparator is connected to the second end of the sampling resistor, the positive input of the second comparator is connected to the third preset signal source, and the output of the third comparator is connected to the base of the first transistor.

[0029] Preferably, the second control module further includes: a second PID controller and a fourth preset signal source;

[0030] The negative input terminal of the second PID controller is connected to the second terminal of the sampling resistor, and the positive input terminal of the second PID controller is connected to the fourth preset signal source.

[0031] The second PID controller includes: a second operational amplifier, a fourth resistor, and a fourth capacitor;

[0032] The fourth resistor and the fourth capacitor are connected in series between the negative input terminal and the output terminal of the second operational amplifier.

[0033] Preferably, it further includes: a voltage regulator diode;

[0034] The cathode of the Zener diode is connected to the second terminal of the second resistor, the first terminal of the third resistor, and the base of the first transistor. The anode of the Zener diode is connected to the second terminal of the sampling resistor, the second terminal of the second capacitor, the second terminal of the third capacitor, and the second terminal of the third resistor.

[0035] Preferably, the regulating tube further includes a second transistor, and the second control module includes a third comparator and a fifth preset signal source;

[0036] The second transistor is an NPN type transistor;

[0037] The emitter of the second transistor is connected to the second terminal of the sampling resistor, the base of the second transistor is connected to the output terminal of the third comparator, and the collector of the second transistor is connected to the base of the first transistor.

[0038] The negative input of the third comparator is connected to the fifth preset signal source, and the positive input of the third comparator is connected to the second end of the sampling resistor.

[0039] Preferably, the second control module further includes a hysteresis comparator, which includes a fourth comparator, a diode, a fifth resistor, and a sixth resistor.

[0040] The first end of the sixth resistor is connected to the output of the fourth comparator, and the second end of the sixth resistor is connected to the anode of the diode.

[0041] The cathode of the diode is connected to the positive input terminal of the fourth comparator and the first terminal of the fifth resistor;

[0042] The second terminal of the fifth resistor is connected to the sampling resistor.

[0043] This application provides a drive power supply with an auxiliary output circuit, comprising a main output circuit, an auxiliary output circuit, a first control module, a load resistor, a switching transistor, and a feedback circuit. It further includes a second control module, an adjustment transistor, and a sampling resistor. The adjustment transistor is connected in series in the auxiliary output circuit. The sampling resistor is connected in series in the auxiliary output circuit to sample the output current of the auxiliary output circuit, obtaining a current sampling value. The input terminal of the first control module is connected to the sampling resistor, and the output terminal of the first control module is connected to the control terminal of the switching transistor, used to control the switching transistor's on / off state based on the current sampling value. The switching transistor is connected in series with the load resistor and then in parallel to the output terminal of the main output circuit. The input terminal of the second control module is connected to the sampling resistor, and the output terminal of the second control module is connected to the control terminal of the adjustment transistor, so as to adjust the impedance of the adjustment transistor according to the current sampling value. The input terminal of the feedback circuit is connected to the output terminal of the main output circuit, used to detect the current or voltage of the main output circuit to obtain a detection value. The output terminal of the feedback circuit is connected to the control terminal of the main circuit corresponding to the auxiliary output circuit, which contains a primary winding, used to adjust the power transmitted by the main circuit based on the comparison of the detection value with a reference parameter. In this application's drive power supply, when the auxiliary output circuit is loaded while the main output circuit is unloaded or lightly loaded, on the one hand, the second control module controls the impedance of the regulating tube to increase, thereby reducing the output voltage of the auxiliary output circuit and temporarily reducing its output power. On the other hand, the first control module controls the switching tube to turn on, connecting the load resistor to the main output circuit, increasing the load on the main output circuit. Thus, the feedback circuit controls the output power of the main circuit to increase, meeting the loading requirements of the auxiliary output circuit. This not only solves the problem that the auxiliary output circuit cannot carry the load normally when the auxiliary output circuit is heavily loaded while the main output circuit is unloaded or lightly loaded, but also ensures that the load resistor is only connected to the main output circuit when the auxiliary output circuit is heavily loaded, without increasing standby power loss at other times. Furthermore, during the intervals when the main circuit adjusts its output power through the feedback circuit, the control circuit can increase the impedance of the regulating tube to quickly reduce or cut off the output power of the auxiliary output circuit, avoiding the drive power supply from malfunctioning during the adjustment process. Attached Figure Description

[0044] To more clearly illustrate the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 A circuit diagram of a drive power supply with an auxiliary output circuit provided for an embodiment of this application;

[0046] Figure 2 A circuit diagram of the first control module provided in an embodiment of this application;

[0047] Figure 3 A first circuit diagram of the second control module provided in the embodiments of this application;

[0048] Figure 4 A second circuit diagram of the second control module provided in the embodiments of this application;

[0049] Figure 5 A third circuit diagram of the second control module provided in the embodiments of this application;

[0050] Figure 6 A fourth circuit diagram of the second control module provided in the embodiments of this application;

[0051] Figure 7 The fifth circuit diagram of the second control module provided in the embodiments of this application. Detailed Implementation

[0052] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this application.

[0053] The core of this application is to provide a drive power supply with an auxiliary output circuit.

[0054] To enable those skilled in the art to better understand the present application, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0055] Figure 1 A circuit diagram of a drive power supply with an auxiliary output circuit provided in an embodiment of this application includes a main output circuit, an auxiliary output circuit, a first control module, a load resistor, a switching transistor, and a feedback circuit, and further includes a second control module, an adjustment transistor, and a sampling resistor;

[0056] The regulating tube is connected in series in the auxiliary output circuit;

[0057] The sampling resistors are connected in series in the auxiliary output circuit to sample the output current of the auxiliary output circuit and obtain the current sample value.

[0058] The input terminal of the first control module is connected to the sampling resistor, and the output terminal of the first control module is connected to the control terminal of the switching transistor, which is used to control the switching transistor to turn on and off according to the current sampling value.

[0059] The switching transistor is connected in series with the load resistor and then in parallel with the output terminal of the main output circuit;

[0060] The input terminal of the second control module is connected to the sampling resistor, and the output terminal of the second control module is connected to the control terminal of the adjustment tube, so as to adjust the impedance of the adjustment tube according to the current sampling value.

[0061] The input terminal of the feedback circuit is connected to the output terminal of the main output circuit to detect the current or voltage of the main output circuit and obtain the detection value. The output terminal of the feedback circuit is connected to the control terminal of the main circuit containing the primary winding in the auxiliary output circuit to adjust the power transmitted by the main circuit based on the comparison between the detection value and the reference parameter.

[0062] In a specific embodiment, such as Figure 1 As shown, the circuit includes a main output circuit 1, an auxiliary output circuit 2, a first control module 3, a load resistor R0, a switching transistor S1, and a feedback circuit 6. It also includes a second control module 4, an adjustment transistor T, and a sampling resistor R22. The adjustment transistor T is connected in series in the auxiliary output circuit 2; LED5 is the load of the main output circuit; the main output circuit also includes anti-reverse diodes D1 and D2; resistor R11 and sampling resistor R22 are connected in series in the main output circuit 1 and auxiliary output circuit 2 respectively, used to sample the output current of the main output circuit 1 and auxiliary output circuit 2 to obtain a first current sampling value and a second current sampling value; the input terminal of the first control module 3 is connected to resistor R11 to obtain the first current sampling value; the output terminal of the first control module 3 is connected to the control terminal of the switching transistor S1, used to control the switching on and off of the switching transistor S1 according to the first current sampling value; the switching transistor S1 is connected in series with the load resistor R0 and then in parallel to the output terminal of the main output circuit 1; the input terminal of the second control module 4 is connected to... The sampling resistor R22 in the auxiliary output circuit 2 is connected to obtain the second current sampling value. The output terminal of the second control module 4 is connected to the control terminal of the regulating transistor T so as to adjust the impedance of the regulating transistor T according to the second current sampling value. The second control module 4 controls the equivalent impedance of the regulating transistor T during the interval when the output power is adjusted through the feedback circuit in the main circuit. It can increase the impedance of the regulating transistor through the control circuit to quickly reduce or cut off the output power of the auxiliary circuit, so as to avoid the driving power supply from malfunctioning during the adjustment process.

[0063] The second control module 4 compares the detected current sampling signal with the second reference signal and controls the output of module T. When the current sampling signal is higher than the reference signal, the impedance of module T is increased or cut off to reduce the output power of the auxiliary output circuit. Simultaneously, the first control module 3 compares the detected current sampling signal with the first reference signal and controls the output of module S1. When the current sampling signal is higher than the reference signal, module S1 is turned on to connect R0 to the output of the main output circuit. In other words, when the auxiliary output circuit is loaded and the main output circuit is unloaded or lightly loaded (when the LED5 light is dim or not lit), the first control module 3 turns on S1 to connect R0 to the main output circuit. During the intervals when the first control module 3 controls S1 to be on, the second control module 4 adjusts the impedance of module T to quickly reduce or cut off the auxiliary output power, preventing the drive power supply from malfunctioning during the adjustment of the load resistor R0.

[0064] Feedback circuit 6 controls the main switch in the primary circuit of the transformer based on the current magnitude collected in the main output circuit 1, thereby controlling the main output circuit 1 to maintain a stable current output.

[0065] This application uses a first control module to control whether the load resistor is connected, and a second control module to adjust the impedance of the regulating transistor. The control functions of both modules are performed simultaneously when the main transmission circuit is lightly loaded or unloaded, and the adjustment is instantaneous with no time delay. However, feedback circuits typically have a time delay. Specifically, when an increase in the electrical parameters of the main output circuit is detected, such as an increase in the main output voltage or current, the feedback circuit compares the electrical parameters with reference parameters (e.g., through a PI proportional-integral regulator) and transmits a control signal to the switching transistor in the main circuit. This changes the duty cycle or frequency of the switching transistor to increase the transmission power of the main circuit. This process is a closed-loop adjustment process. To ensure the circuit eventually returns to steady-state operation, the adjustment speed of the feedback circuit is usually slow, specifically reflected in the parameter settings of the integral circuit. This results in a certain time delay in the adjustment of the feedback circuit. Therefore, in the technical solution of this application, simply setting the first control module and the load resistor cannot achieve the goal of quickly adjusting the transmission power of the main circuit. As for the second control module and the regulating transistor, no lengthy adjustment time is required. Upon detecting an increase in current in the auxiliary output circuit, the regulating transistor's impedance can be increased or cut off immediately. The adjustment action is instantaneous, with virtually no time delay. This results in faster adjustment efficiency, reducing the likelihood of the main and auxiliary output circuits failing to output voltage or current normally, thus preventing the circuit from reaching a steady state.

[0066] Based on the above embodiments, as a preferred embodiment, the feedback circuit includes a control chip, a first loop, and a first preset signal source;

[0067] The input terminal of the first loop is connected to the main output loop, the base terminal of the first loop is connected to the first preset signal source, and the output terminal of the first loop is connected to the input terminal of the control chip.

[0068] The output terminal of the control chip is connected to the control terminal of the main circuit containing the primary winding.

[0069] As a preferred embodiment, the first loop is a first PID controller, which includes a first operational amplifier, a first capacitor, and a first resistor.

[0070] In other words, the first control module compares the signal sampled by R22 with the first reference signal, and the second control module compares the signal sampled by R22 with the second reference signal. The two reference signals may be equal or unequal.

[0071] In a specific embodiment, such as Figure 1 As shown, the feedback circuit 6 includes a control chip I1, a first operational amplifier Q1, a first resistor R1, a first capacitor C1, and a first preset signal source 7. R11 and C1 are connected in series between the negative input terminal and the output terminal of Q1 to form a first PID regulator. The positive input terminal of Q1 is connected to the first preset signal source 7, and the output terminal of Q1 is connected to the input terminal of I1 to receive the output signal of the first PID regulator. The output terminal of I1 is connected to the control terminal of the main circuit containing the primary winding to control the switching transistor S1 in the main output circuit.

[0072] It should be noted that the specific devices in the feedback circuit provided in this application embodiment are only one possible implementation method, but are not limited to this only implementation method. Users can set them themselves according to their needs.

[0073] As can be seen from the embodiments of this application, the feedback circuit 6 controls whether the main circuit increases the transmitted power based on the comparison between the sampled value of the main output circuit current and the reference value, thereby stabilizing the output current of the main circuit at the set value. Therefore, when the auxiliary output circuit is loaded while the main output circuit is unloaded or lightly loaded, on the one hand, the second control module 4 detects an increase in the current of the auxiliary output circuit, indicating that the auxiliary output circuit is loaded, and then controls the impedance T to increase, thereby reducing the transient value of the output power of the auxiliary output circuit; on the other hand, the first control module 3 also controls R0 to be connected to the main output circuit, thereby increasing the load of the main output circuit, through feedback. Circuit 6 controls the main circuit to increase the output power to meet the loading requirements of the auxiliary output circuit. This not only solves the problem that the auxiliary circuit cannot carry the load normally when the auxiliary circuit is heavily loaded while the main circuit is unloaded or lightly loaded, but also ensures that R0 is only connected to the main circuit when the auxiliary circuit is heavily loaded, thus not increasing standby power loss at other times. At the same time, during the interval when the main circuit adjusts the output power through feedback circuit 6, the impedance T can be increased through the second control module 4 to quickly reduce or cut off the output power of the auxiliary circuit, thus avoiding the drive power supply from malfunctioning during the adjustment of R0 and feedback circuit 6.

[0074] Based on the above embodiments, as a preferred embodiment, the first control module includes a first comparator and a second preset signal source;

[0075] In one embodiment, the negative input terminal of the first comparator is connected to the sampling resistor, the positive input terminal of the first comparator is connected to the second preset signal source, and the output terminal of the first comparator is connected to the control terminal of the switching transistor. According to the operating characteristics of the comparator, when the voltage at the positive input terminal of the comparator is greater than the voltage at the negative input terminal, the output terminal outputs a high level.

[0076] In a specific embodiment, since the function of the first control module is to make comparisons, therefore, as a preferred option, such as Figure 2 As shown, the first control module 3 includes a first comparator Q2 and a second preset signal source 8; wherein, the positive input terminal of Q2 is connected to the second terminal of R22, the negative input terminal of Q2 is connected to the second preset signal source 8, and the output terminal of Q2 is connected to the control terminal of S1.

[0077] In other words, the current compared in Q2 is the output value (reference voltage) of the second preset signal source 8 and the sampled value of R22. When the sampled value is greater than the reference voltage, its output terminal outputs a drive signal to control S1 to turn on.

[0078] It should be noted that the embodiments in this application are only one possible implementation method, but are not limited to this only implementation method. Users can set their own implementation methods according to their needs.

[0079] Based on the above embodiments, as a preferred embodiment, the regulating transistor is a first transistor, and the second control module includes a second comparator and a third preset signal source;

[0080] In a specific embodiment, if the adjusting transistor T is the first transistor G1, and G1 is an NPN transistor, and the second control module 4 includes a second comparator Q3 and a third preset signal source 9, such as... Figure 3 As shown, the circuit connections at this time include: the collector of G1 is connected to the cathode of D2; the emitter of G1 is connected to the second terminal of R11 and the positive input terminal of Q1; the base of G1 is connected to the output terminal of Q3; the positive input terminal of Q3 is connected to the third preset signal source 9; and the negative input terminal of Q3 is connected to the second terminal of R22.

[0081] In other words, Q3 compares the current output from the third preset signal source 9 (reference value) and the current sampled from R22. When the sampled current value is less than the reference value, control G1 to turn on and operate in a state with a smaller equivalent impedance; otherwise, increase the equivalent impedance of G1 or control G1 to turn off.

[0082] Based on this, and according to the operating characteristics of the transistor, the circuit also needs to include a second resistor R2 and a third resistor R3. Meanwhile, the second capacitor C2 and the third capacitor C3 filter the circuit.

[0083] In this configuration, the first end of R2 is connected to the cathode of D2 and the collector of G1, and the second end of R2 is connected to the base of G1; the first end of R3 is connected to the second end of R2 and the base of G1, and the second end of R3 is connected to the second end of R2; the first end of C2 is connected to the cathode of D2 and the first end of R2, and the second end of R2 is connected to the second end of R22 and the second end of R3; the first end of C3 is connected to the emitter of G1, and the second end of C3 is connected to the second end of R22, the second end of C2, and the second end of R3.

[0084] It should be noted that the first transistor in the connection relationship described in the embodiments of this application is NPN type, but not limited to, it can be PNP type. Depending on the working characteristics of different types of transistors, the connection relationship of the transistor in the control module needs to be modified accordingly.

[0085] It should also be noted that the embodiments in this application are only one possible implementation method, but are not limited to this only implementation method. Users can set their own implementation methods according to their needs.

[0086] Based on the above embodiments, as a preferred embodiment, the second control module further includes: a second PID regulator and a fourth preset signal source;

[0087] The negative input terminal of the second PID controller is connected to the second terminal of the sampling resistor, and the positive input terminal of the second PID controller is connected to the fourth preset signal source.

[0088] The second PID controller includes: a second operational amplifier, a fourth resistor, and a fourth capacitor;

[0089] The fourth resistor and the fourth capacitor are connected in series between the negative input terminal and the output terminal of the second operational amplifier.

[0090] In specific embodiments, such as Figure 4 As shown, the second operational amplifier Q4, the fourth resistor R4, the fourth capacitor C4, and the fourth preset signal source 10 are connected. R4 and C4 are connected in series between the negative input terminal and the output terminal of Q4. That is, the output voltage of the PID controller is positively correlated with the difference between its positive and negative input terminals. Its output terminal controls the base of the first transistor G1, thereby controlling the current at the emitter and collector of the first transistor G1.

[0091] It should also be noted that the fourth resistor and the fourth capacitor can be interchanged, and this application does not limit this.

[0092] In addition, it also includes the Zener diode H; such as Figure 5 As shown, the cathode of H is connected to the second end of R2, the first end of R3, and the base of G1, while the anode of H is connected to the second end of R22, the second end of C2, the second end of C3, and the second end of R3.

[0093] When the auxiliary output circuit is in a steady state, that is, when the second control module 4 does not control the regulating tube T, the auxiliary output circuit works in a regulated output state, that is, the three-terminal voltage regulator circuit works, and its output voltage is determined by the Zener diode.

[0094] It should be noted that the embodiments in this application are only one possible implementation method, but are not limited to this only implementation method. Users can set their own implementation methods according to their needs.

[0095] The Zener diode provided in this embodiment serves as a three-terminal voltage regulator for the circuit, ensuring its stability.

[0096] Based on the above embodiments, as a preferred embodiment, the adjusting tube further includes a second transistor, and the second control module includes a third comparator and a fifth preset signal source:

[0097] The second transistor is an NPN type transistor;

[0098] The emitter of the second transistor is connected to the second terminal of the sampling resistor, the base of the second transistor is connected to the output terminal of the third comparator, and the collector of the second transistor is connected to the base of the first transistor.

[0099] The negative input of the third comparator is connected to the fifth preset signal source, and the positive input of the third comparator is connected to the second end of the sampling resistor.

[0100] In specific embodiments, such as Figure 6 As shown, if the regulating transistor T includes a first transistor G1 and a second transistor G2, and the second control module 4 includes a third comparator Q5 and a fifth preset signal source 11, the emitter of G2 is connected to the second end of R22, and the base of G2 is connected to the output end of Q5; the negative input end of Q5 is connected to the fifth preset signal source 10, and the positive input end of Q5 is connected to the second end of R22.

[0101] It should be noted that the regulating transistor in this embodiment includes two transistors, and may also include a Zener diode. The second control module may also include a fourth resistor and a fourth capacitor, etc. The specific embodiments are the same as those described above, and will not be repeated here.

[0102] Based on the above embodiments, as a preferred embodiment, the second control module further includes: a hysteresis comparator, which includes: a fourth comparator, a diode, a fifth resistor, and a sixth resistor;

[0103] The first end of the sixth resistor is connected to the output of the fourth comparator, and the second end of the sixth resistor is connected to the anode of the diode.

[0104] The cathode of the diode is connected to the positive input terminal of the fourth comparator and the first terminal of the fifth resistor;

[0105] The second terminal of the fifth resistor is connected to the sampling resistor.

[0106] In specific embodiments, such as Figure 7 As shown, the second control module 4 further includes: a fourth comparator Q6, a diode P, a fifth resistor R5 and a sixth resistor R6; the first end of R6 is connected to the output terminal of Q6, and the second end of R6 is connected to the anode of P; the cathode of P is connected to the positive input terminal of Q6 and the first end of R5; the second end of R5 is connected to R22.

[0107] In the second control module provided in this application embodiment, the diode is connected in series in the hysteresis circuit to achieve unidirectional hysteresis, and has unidirectional hysteresis function. When the control adjustment transistor T is cut off or the impedance increases, there is no hysteresis function, but when the control adjustment transistor T is turned on or the impedance decreases, there is hysteresis function.

[0108] This application provides a drive power supply with an auxiliary output circuit, comprising a main output circuit, an auxiliary output circuit, a first control module, a load resistor, a switching transistor, and a feedback circuit. It further includes a second control module, an adjustment transistor, and a sampling resistor. The adjustment transistor is connected in series in the auxiliary output circuit. The sampling resistor is connected in series in the auxiliary output circuit to sample the output current of the auxiliary output circuit, obtaining a current sampling value. The input terminal of the first control module is connected to the sampling resistor, and the output terminal of the first control module is connected to the control terminal of the switching transistor, used to control the switching transistor's on / off state based on the current sampling value. The switching transistor is connected in series with the load resistor and then in parallel to the output terminal of the main output circuit. The input terminal of the second control module is connected to the sampling resistor, and the output terminal of the second control module is connected to the control terminal of the adjustment transistor, so as to adjust the impedance of the adjustment transistor according to the current sampling value. The input terminal of the feedback circuit is connected to the output terminal of the main output circuit, used to detect the current or voltage of the main output circuit to obtain a detection value. The output terminal of the feedback circuit is connected to the control terminal of the main circuit corresponding to the auxiliary output circuit, which contains a primary winding, used to adjust the power transmitted by the main circuit based on the comparison of the detection value with a reference parameter. In this application's drive power supply, when the auxiliary output circuit is loaded while the main output circuit is unloaded or lightly loaded, on the one hand, the control module detects an increase in the current of the auxiliary output circuit, indicating that the auxiliary output circuit is loaded. It then controls the impedance of the regulating transistor to increase, causing the output voltage of the auxiliary output circuit to decrease, thereby temporarily reducing the output power of the auxiliary output circuit. On the other hand, the control module also controls the load resistor to be connected to the main output circuit, increasing the load on the main output circuit. Through the feedback circuit, it controls the output power of the main circuit to increase, thus meeting the loading requirements of the auxiliary output circuit. This not only solves the problem of the auxiliary output circuit not being able to carry the load normally when the auxiliary output circuit is heavily loaded while the main output circuit is unloaded or lightly loaded, but also ensures that the load resistor is only connected to the main output circuit when a heavy load is detected in the auxiliary output circuit, preventing increased standby power loss at other times. Furthermore, during the intervals when the main output circuit adjusts its output power through the feedback circuit, the control circuit can increase the impedance of the regulating transistor to quickly reduce or cut off the output power of the auxiliary output circuit, avoiding any malfunction of the drive power supply during the adjustment of the load resistor and feedback circuit.

[0109] The foregoing has provided a detailed description of a drive power supply with an auxiliary output circuit provided in this application. The various embodiments in the specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to in the method section. It should be noted that those skilled in the art can make several improvements and modifications to this application without departing from the principles of this application, and these improvements and modifications also fall within the protection scope of the claims of this application.

[0110] It should also be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A drive power supply with an auxiliary output circuit, comprising a main output circuit, an auxiliary output circuit, a first control module, a load resistor, a switching transistor, and a feedback circuit, characterized in that, Also includes: Second control module, adjustment tube and sampling resistor; The regulating tube is connected in series in the auxiliary output circuit; The sampling resistor is connected in series in the auxiliary output circuit to sample the output current of the auxiliary output circuit and obtain the current sampling value. The input terminal of the first control module is connected to the sampling resistor, and the output terminal of the first control module is connected to the control terminal of the switching transistor, for controlling the switching transistor to turn on or off according to the current sampling value; The switching transistor is connected in series with the load resistor and then in parallel to the output terminal of the main output circuit. The input terminal of the second control module is connected to the sampling resistor, and the output terminal of the second control module is connected to the control terminal of the adjustment tube, so as to adjust the impedance of the adjustment tube according to the current sampling value. The input terminal of the feedback circuit is connected to the output terminal of the main output circuit, and is used to detect the current or voltage of the main output circuit to obtain a detection value. The output terminal of the feedback circuit is connected to the control terminal of the main circuit containing the primary winding corresponding to the auxiliary output circuit, and is used to adjust the power transmitted by the main circuit according to the comparison between the detection value and the reference parameter.

2. The drive power supply with an auxiliary output circuit according to claim 1, characterized in that, The feedback circuit includes a control chip, a first loop, and a first preset signal source; Wherein, the input terminal of the first loop is connected to the main output loop, the base terminal of the first loop is connected to the first preset signal source, and the output terminal of the first loop is connected to the input terminal of the control chip; The output terminal of the control chip is connected to the control terminal of the main circuit containing the primary winding.

3. The drive power supply with an auxiliary output circuit according to claim 2, characterized in that, The first loop is a first PID controller, which includes a first operational amplifier, a first capacitor, and a first resistor.

4. The drive power supply with an auxiliary output circuit according to any one of claims 1-3, characterized in that, The first control module includes a first comparator and a second preset signal source; The negative input terminal of the first comparator is connected to the sampling resistor, the positive input terminal of the first comparator is connected to the second preset signal source, and the output terminal of the first comparator is connected to the control terminal of the switching transistor.

5. The drive power supply with an auxiliary output circuit according to claim 4, characterized in that, The regulating transistor is a first transistor; The first transistor is an NPN transistor; The second control module includes a second resistor, a third resistor, a second capacitor, and a third capacitor; Wherein, the first end of the second resistor is connected to the collector of the first transistor, and the second end of the second resistor is connected to the base of the first transistor; The first end of the third resistor is connected to the second end of the second resistor and the base of the first transistor, and the second end of the third resistor is connected to the second end of the sampling resistor; The first terminal of the second capacitor is connected to the first terminal of the second resistor, and the second terminal of the second capacitor is connected to the second terminal of the sampling resistor and the second terminal of the third resistor; The first terminal of the third capacitor is connected to the emitter of the first transistor, and the second terminal of the third capacitor is connected to the second terminal of the sampling resistor, the second terminal of the second capacitor, and the second terminal of the third resistor.

6. The drive power supply with an auxiliary output circuit according to claim 5, characterized in that, The second control module also includes a second comparator and a third preset signal source; The negative input terminal of the second comparator is connected to the second terminal of the sampling resistor, the positive input terminal of the second comparator is connected to the third preset signal source, and the output terminal of the second comparator is connected to the base of the first transistor.

7. The drive power supply with an auxiliary output circuit according to claim 5, characterized in that, The second control module further includes: a second PID controller and a fourth preset signal source; The negative input terminal of the second PID controller is connected to the second terminal of the sampling resistor, and the positive input terminal of the second PID controller is connected to the fourth preset signal source; The second PID controller includes: a second operational amplifier, a fourth resistor, and a fourth capacitor; The fourth resistor and the fourth capacitor are connected in series between the negative input terminal and the output terminal of the second operational amplifier.

8. The drive power supply with an auxiliary output circuit according to claim 5, characterized in that, Also includes: Zener diode; The cathode of the Zener diode is connected to the second terminal of the second resistor, the first terminal of the third resistor, and the base of the first transistor. The anode of the Zener diode is connected to the second terminal of the sampling resistor, the second terminal of the second capacitor, the second terminal of the third capacitor, and the second terminal of the third resistor.

9. The drive power supply with an auxiliary output circuit according to claim 5, characterized in that, The adjustment tube also includes a second transistor, and the second control module includes a third comparator and a fifth preset signal source; The second transistor is an NPN transistor; The emitter of the second transistor is connected to the second terminal of the sampling resistor, the base of the second transistor is connected to the output terminal of the third comparator, and the collector of the second transistor is connected to the base of the first transistor. The negative input terminal of the third comparator is connected to the fifth preset signal source, and the positive input terminal of the third comparator is connected to the second terminal of the sampling resistor.

10. The drive power supply with an auxiliary output circuit according to any one of claims 5-9, characterized in that, The second control module further includes a hysteresis comparator, which comprises: a fourth comparator, a diode, a fifth resistor, and a sixth resistor; Wherein, the first end of the sixth resistor is connected to the output end of the fourth comparator, and the second end of the sixth resistor is connected to the anode of the diode; The cathode of the diode is connected to the positive input terminal of the fourth comparator and the first terminal of the fifth resistor; The second terminal of the fifth resistor is connected to the sampling resistor.

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