Diode driving circuit

Abstract

The utility model discloses a diode driving circuit which comprises a current control circuit and a fast driving circuit. The current control circuit comprises a diode D1, a laser diode LD, a switch tube S1, a resistor R1 and a first control circuit; the fast driving circuit comprises an inductor L1, a diode D2, a switching tube S2, a resistor R2 and a second control circuit; according to the utility model, the problems of current delay and light leakage of a traditional circuit can be solved without a complex control circuit, and the light emitting speed and reliability of a laser system are improved.

Description

Technical Field

[0001] This utility model belongs to the field of laser diode technology, and specifically relates to a diode driving circuit. Background Technology

[0002] The main components of a fiber laser are the pump source, optical resonant cavity, and fiber gain medium. The pump source is a crucial fundamental component of the entire system, consisting of a high-power semiconductor laser diode and a driving circuit. The emission velocity of the pump source determines the overall emission velocity of the fiber laser, which in turn is determined by the driving circuit. With industry advancements, the required frequencies for fiber lasers are increasing. To achieve high frequencies, the laser diode drive current needs to rise rapidly to a set value.

[0003] Traditional circuits such as Figure 1 The corresponding timing sequence is as follows Figure 2 The control signal causes switches S1 and S2 to turn on simultaneously. Since the conduction path impedance of switch S2 is much smaller than that of switch S1, the current only flows from Vin through inductor L1, switch S2, and resistor R2 to ground GND to form a charging circuit. When the current in inductor L1 rises to the set maximum current value, switch S2 turns off. Since the current in inductor L1 cannot change abruptly, the maximum current in inductor L1 flows through laser diode LD, switch S1, and resistor R1 to ground GND to form a circuit, thus enabling the rapid rise of the laser diode LD current.

[0004] However, this circuit causes a delay in the control signal and the laser diode LD current, such as... Figure 2 Delay t between control signal 1 and LD current D This delay slows down the light output speed of the laser diode (LD), and since the delay varies with the current, this traditional circuit cannot be used in fiber lasers with multi-stage pump sources that have high timing requirements. Furthermore, when the delay of control circuit 2 is longer than that of control circuit 1, the switching transistor S2 turns on slower than the switching transistor S1, resulting in leakage current in the laser diode (LD) and consequently, light leakage in the fiber laser. Solving this leakage problem requires additional circuitry, increasing system cost, size, and reducing reliability. Utility Model Content

[0005] The present invention aims to overcome at least one of the defects in the prior art and provide a diode driving circuit to solve the problems of slow light output, inability to be applied to multi-stage pumping systems, and light leakage risk in the prior art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A diode driving circuit is provided, including a current control circuit and a fast driving circuit. The current control circuit includes a diode D1, a laser diode LD, a switch S1, a resistor R1, and a first control circuit. The fast driving circuit includes an inductor L1, a diode D2, a switch S2, a resistor R2, and a second control circuit. The anode of diode D1 and one end of inductor L1 are electrically connected to an input voltage Vin. The cathodes of diode D1 and D2, and the anode of laser diode LD are electrically connected. The cathode of laser diode LD is electrically connected to the second end of switch S1. The first end of switch S1 is connected to the first control circuit. The third terminal of the control circuit is electrically connected. The third terminal of the switch S1, one end of the resistor R1, and the second terminal of the first control circuit are electrically connected together. The other end of the resistor R1 is electrically connected to ground GND. The first terminal of the first control circuit is used to receive the first control signal. The other end of the inductor L1, the anode of the diode D2, and the second terminal of the switch S2 are electrically connected together. The first terminal of the switch S2 and the third terminal of the second control circuit are electrically connected together. The third terminal of the switch S2, one end of the resistor R2, and the second terminal of the second control circuit are electrically connected together. The other end of the resistor R2 is electrically connected to ground GND. The first terminal of the second control circuit is used to receive the second control signal.

[0008] Preferably, it further includes a second absorption circuit, the first end of which is electrically connected to the cathode of diode D1, the cathode of diode D2, and the anode of laser diode LD, and the second end of which is connected to the anode of diode D1 and one end of inductor L1.

[0009] Preferably, it further includes a second absorption circuit, the first end of which is electrically connected to the cathode of diode D1, the cathode of diode D2, and the anode of laser diode LD, and the second end of which is grounded to GND.

[0010] Preferably, it further includes a first absorption circuit, which includes a diode D3 connected in reverse parallel with the laser diode LD.

[0011] Preferably, the second absorption circuit includes a resistor R3 and a capacitor C1; one end of the resistor R3 is the second end of the second absorption circuit, the other end of the resistor R3 is electrically connected to one end of the capacitor C1, and the other end of the capacitor C1 is the first end of the second absorption circuit.

[0012] Preferably, the second absorption circuit includes a diode TVS and a capacitor C1; the anode of the diode TVS is the second terminal of the second absorption circuit, the cathode of the diode TVS is electrically connected to one end of the capacitor C1, and the other end of the capacitor C1 is the first terminal of the second absorption circuit.

[0013] Preferably, the second absorption circuit includes a resistor R3 and a diode D4; one end of the resistor R3 is the second end of the second absorption circuit, the other end of the resistor R3 is electrically connected to the cathode of the diode D4, and the anode of the diode D4 is the first end of the second absorption circuit.

[0014] Preferably, resistor R3 is a varistor or an adjustable resistor.

[0015] Preferably, the second absorption circuit includes a diode TVS and a diode D4; the anode of the diode TVS is the second terminal of the second absorption circuit, the cathodes of the diode TVS and the cathodes of the diode D4 are electrically connected, and the anode of the diode D4 is the first terminal of the second absorption circuit.

[0016] Preferably, the second absorption circuit includes a diode TVS; the anode of the diode TVS is the second terminal of the second absorption circuit, and the cathode of the diode TVS is the first terminal of the second absorption circuit.

[0017] Preferably, the second absorption circuit includes a resistor RV; one end of the varistor RV is the first end of the second absorption circuit, and the other end of the resistor RV is the second end of the second absorption circuit.

[0018] The specific working principle of this utility model will be analyzed and explained in specific embodiments, and will not be repeated here. Compared with the prior art, the beneficial effects of this utility model are as follows:

[0019] 1) Effectively solves the problem of slow light output speed caused by delay; effectively solves the problem of inapplicability to multi-stage pumping systems caused by inconsistent delay; effectively solves the problem of light leakage caused by the slower conduction of switch S2 compared to switch S1.

[0020] 2) Reducing the voltage stress on switching transistors S1 and S2 can improve temperature rise and make selection easier;

[0021] 3) The circuit works on a simple principle and can use existing control circuit schemes, making it easy to design. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a traditional diode driver circuit.

[0023] Figure 2 This is a timing diagram for a traditional diode driver circuit.

[0024] Figure 3 This is a schematic diagram of a diode driving circuit according to the present invention.

[0025] Figure 4 This is a timing diagram of a diode driving circuit according to the present invention.

[0026] Figure 5 This is a schematic diagram of a diode driving circuit including an absorption circuit according to the present invention.

[0027] Figure 6 This is another schematic diagram of a diode driving circuit including an absorption circuit according to the present invention.

[0028] Figures 7-14 This is a schematic diagram of the second absorption circuit of this utility model.

[0029] Explanation of reference numerals in the attached figures:

[0030] Vin represents DC input source; L represents inductor; S represents switch; C represents capacitor; D represents diode; R represents resistor; LD represents laser diode; TVS represents transient voltage suppressor; RV represents varistor. Detailed Implementation

[0031] The present invention and its beneficial effects will be further described in detail below with reference to specific embodiments and accompanying drawings. However, the specific embodiments of the present invention are not limited thereto.

[0032] Electrical connection: Electrical connection means not only direct connection, but also indirect connection (that is, other components can be connected between electrically connected objects), and includes methods such as inductive coupling.

[0033] First embodiment:

[0034] refer to Figure 3 , Figure 3The schematic diagram of the diode driving circuit includes a current control circuit and a fast driving circuit. The current control circuit includes a diode D1, a laser diode LD, a switch S1, a resistor R1, a control signal 1 (first control signal), and a control circuit 1 (first control circuit). The fast driving circuit includes an inductor L1, a diode D2, a switch S2, a resistor R2, a control signal 2 (second control signal), and a control circuit 2 (second control circuit). The anode of diode D1, one end of inductor L1, and input voltage Vin are electrically connected together. The cathodes of diode D1, diode D2, and laser diode LD are electrically connected together. The first terminal of the switch S1 is electrically connected to the second terminal of the control circuit 1. The third terminal of the switch S1, one end of the resistor R1, and the second terminal of the control circuit 1 are electrically connected together. The other end of the resistor R1 is electrically connected to ground GND. The control signal 1 is electrically connected to the first terminal of the control circuit 1. The other end of the inductor L1, the anode of the diode D2, and the second terminal of the switch S2 are electrically connected together. The first terminal of the switch S2 is electrically connected to the third terminal of the control circuit 2. The third terminal of the switch S2, one end of the resistor R2, and the second terminal of the control circuit 2 are electrically connected together. The other end of the resistor R2 is electrically connected to ground GND. The control signal 2 is electrically connected to the first terminal of the control circuit 2.

[0035] In this embodiment, both switch S1 and switch S2 are MOS transistors, with the first terminal of the switch being the gate, the second terminal being the drain, and the third terminal being the source.

[0036] The timing diagram for this embodiment is referenced. Figure 4Control signal 1 is a pulse signal with variable frequency, amplitude, and duty cycle. Control signal 2 is a pulse signal established simultaneously with control signal 1 and controlled to turn off by the signal sampled by resistor R2. In the first stage, switches S1 and S2 are turned on, and the input voltage Vin current is split into two paths. One path flows through diode D1, laser diode LD, switch S1, and resistor R1 to ground, with the laser diode LD current rising slowly. The other path flows through inductor L1, switch S2, and resistor R2 to ground, with the inductor L1 current rising rapidly. In the second stage, when the inductor L1 current reaches the set value, switch S2 is turned off. Since the inductor L1 current cannot change abruptly, the large current in inductor L1 flows through diode D2, laser diode LD, and switch S2 to ground. The circuit formed by switching transistor S1, resistor R1, and ground GND enables a rapid rise in the current of the laser diode LD. Simultaneously, the voltage at the anode of the laser diode LD is raised, causing diode D1 to turn off. In the third stage, the current of the laser diode LD rises to the set value, the voltage at the anode of the laser diode LD recovers, and because the impedance of the diode D1 path is less than that of the inductor L1 and diode D2 path, diode D1 is turned on again, and its current rises slowly. At the same time, the current of diode D2 slowly decreases. The current of the laser diode LD is jointly provided by diodes D1 and D2 and stabilizes at the set value. In the fourth stage, control signal 1 is turned off, switching transistor S1 is turned off, and the current of the laser diode LD decreases, thus completing one cycle.

[0037] The biggest difference between this embodiment and the traditional circuit is that the delay time t is... D This design achieves zero delay between control signal 1 and the laser diode LD current; effectively solves the problem of slow light output speed caused by delay; effectively solves the problem of inapplicability to multi-stage pumping systems caused by inconsistent delays; effectively solves the problem of light leakage caused by the slower conduction of switch S2 compared to switch S1; during the second stage of the above working sequence, when switch S2 is turned off, since there is already current in the laser diode LD, the current in inductor L1 can be quickly discharged to the laser diode LD, and the resonant voltage between inductor L1 and switch S2 will decrease, effectively reducing the voltage stress on switch S2, improving temperature rise and making it easier to select the appropriate type; compared with the traditional circuit, it only adds diodes D1 and D2, and can use existing control circuit schemes, making it easy to design.

[0038] Second embodiment:

[0039] refer to Figure 5 , Figure 5This is a schematic diagram of a diode driving circuit including an absorption circuit, comprising a current control circuit, a fast driving circuit, absorption circuit 1 (first absorption circuit), and absorption circuit 2 (second absorption circuit). The current control circuit includes a diode D1, a laser diode LD, a switch S1, a resistor R1, a control signal 1, and a control circuit 1. The fast driving circuit includes an inductor L1, a diode D2, a switch S2, a resistor R2, a control signal 2, and a control circuit 2. The absorption circuit 1 includes a diode D3. The anode of diode D1, one end of inductor L1, the input voltage Vin, and the second end of absorption circuit 2 are electrically connected together. The cathodes of diode D1, diode D2, the anode of laser diode LD, the first end of absorption circuit 2, and diode D3 are also connected. The cathodes of diodes 3, LD, S1, and D3 are connected together. The first terminal of S1 is connected to the third terminal of control circuit 1. The third terminal of S1, R1, and control circuit 1 are connected together. The other terminal of R1 is connected to ground (GND). Control signal 1 is connected to the first terminal of control circuit 1. The other terminal of inductor L1, D2, and S2 are connected together. The first terminal of S2 is connected to the third terminal of control circuit 2. S2, R2, and control circuit 2 are connected together. The other terminal of R2 is connected to ground (GND). Control signal 2 is connected to the first terminal of control circuit 2.

[0040] Specifically, diode D3 can be composed of multiple diodes connected in series or in parallel in the same direction.

[0041] Specifically, such as Figure 7 As shown, the absorption circuit 2 includes a resistor R3 and a capacitor C1; one end of the resistor R3 is the second end of the absorption circuit 2, the other end of the resistor R3 is electrically connected to one end of the capacitor C1, and the other end of the capacitor C1 is the first end of the absorption circuit 2.

[0042] Specifically, such as Figure 8 As shown, the absorption circuit 2 includes a diode TVS and a capacitor C1; the anode of the diode TVS is the second terminal of the absorption circuit 2, the cathode of the diode TVS is electrically connected to one end of the capacitor C1, and the other end of the capacitor C1 is the first terminal of the absorption circuit 2.

[0043] Specifically, such as Figure 9 As shown, the absorption circuit 2 includes a resistor RV and a capacitor C1; one end of the resistor RV is the second end of the absorption circuit 2, the other end of the resistor RV is electrically connected to one end of the capacitor C1, and the other end of the capacitor C1 is the first end of the absorption circuit 2.

[0044] Specifically, such as Figure 10As shown, the absorption circuit 2 includes a resistor R3 and a diode D4; one end of the resistor R3 is the second end of the absorption circuit 2, and the other end of the resistor R3 is electrically connected to the cathode of the diode D4, while the anode of the diode D4 is the first end of the absorption circuit 2.

[0045] Specifically, such as Figure 11 As shown, the absorption circuit 2 includes a diode TVS and a diode D4; the anode of the diode TVS is the second terminal of the absorption circuit 2, the cathode of the diode TVS and the cathode of the diode D4 are electrically connected, and the anode of the diode D4 is the first terminal of the absorption circuit 2.

[0046] Specifically, such as Figure 12 As shown, the absorption circuit 2 includes a resistor RV and a diode D4; one end of the resistor RV is the second end of the absorption circuit 2, and the other end of the resistor RV is electrically connected to the cathode of the diode D4, while the anode of the diode D4 is the first end of the absorption circuit 2.

[0047] Specifically, the absorption circuit 2 may be composed of any one or more of the above-mentioned preferred embodiments.

[0048] The timing diagram for this embodiment is referenced. Figure 4 The working principle is basically the same as that of the first embodiment, and the same parts will not be repeated here. The difference is that when the switch S2 is turned off in the second stage, the voltage stress increases. The voltage stress can be discharged to the absorption circuit 2 through the diode D2, which reduces the stress on the switch S2 and improves the temperature rise of the switch S2. At the same time, the discharged voltage stress can also be converted back into the energy of the input voltage Vin through the absorption circuit 2, achieving the effect of energy reuse and improved efficiency. The difference is also that when the switch S1 is turned off in the fourth stage, the voltage stress increases. The voltage stress can be discharged to the absorption circuit 2 through the diode D3, which reduces the stress on the switch S1 and improves the temperature rise of the switch S1. At the same time, the discharged voltage stress can also be converted back into the energy of the input voltage Vin through the absorption circuit 2, achieving the effect of energy reuse and improved efficiency.

[0049] Third embodiment:

[0050] refer to Figure 6 , Figure 6This is another schematic diagram of a diode driving circuit including an absorption circuit, comprising a current control circuit, a fast driving circuit, absorption circuit 1, and absorption circuit 2. The current control circuit includes diode D1, laser diode LD, switch S1, resistor R1, control signal 1, and control circuit 1. The fast driving circuit includes inductor L1, diode D2, switch S2, resistor R2, control signal 2, and control circuit 2. The absorption circuit 1 includes at least one diode D3. The second terminal of the absorption circuit 2 is electrically connected to ground GND. The anode of diode D1, one end of inductor L1, and input voltage Vin are all electrically connected. The cathodes of diode D1, diode D2, laser diode LD, the first terminal of absorption circuit 2, and diode D3 are also connected. The cathode of the laser diode LD, the second terminal of the switch S1, and the anode of the diode D3 are all electrically connected. The first terminal of the switch S1 is electrically connected to the third terminal of the control circuit 1. The third terminal of the switch S1, one end of the resistor R1, and the second terminal of the control circuit 1 are all electrically connected. The other end of the resistor R1 is electrically connected to ground GND. The control signal 1 is electrically connected to the first terminal of the control circuit 1. The other end of the inductor L1, the anode of the diode D2, and the second terminal of the switch S2 are all electrically connected. The first terminal of the switch S2 is electrically connected to the third terminal of the control circuit 2. The third terminal of the switch S2, one end of the resistor R2, and the second terminal of the control circuit 2 are all electrically connected. The other end of the resistor R2 is electrically connected to ground GND. The control signal 2 is electrically connected to the first terminal of the control circuit 2.

[0051] Specifically, the absorption circuit 2 includes a resistor R3 and a capacitor C1; one end of the resistor R3 is the second end of the absorption circuit 2, the other end of the resistor R3 is electrically connected to one end of the capacitor C1, and the other end of the capacitor C1 is the first end of the absorption circuit 2.

[0052] Specifically, the absorption circuit 2 includes a diode TVS and a capacitor C1; the anode of the diode TVS is the second terminal of the absorption circuit 2, the cathode of the diode TVS is electrically connected to one end of the capacitor C1, and the other end of the capacitor C1 is the first terminal of the absorption circuit 2.

[0053] Specifically, the absorption circuit 2 includes a resistor RV and a capacitor C1; one end of the resistor RV is the second end of the absorption circuit 2, the other end of the resistor RV is electrically connected to one end of the capacitor C1, and the other end of the capacitor C1 is the first end of the absorption circuit 2.

[0054] Specifically, the absorption circuit 2 includes a diode TVS; the anode of the diode TVS is the second terminal of the absorption circuit 2, and the cathode of the diode TVS is the first terminal of the absorption circuit 2.

[0055] Specifically, the absorption circuit 2 includes a resistor RV; one end of the resistor RV is the second end of the absorption circuit 2, and the other end of the resistor RV is the first end of the absorption circuit 2.

[0056] Specifically, the absorption circuit 2 may be composed of any one or more of the above-mentioned preferred embodiments.

[0057] The timing diagram for this embodiment is referenced. Figure 4 The working principle is basically the same as that of the first embodiment, and the same parts will not be repeated here. The difference is that when the switch S2 is turned off in the second stage, the voltage stress increases. The voltage stress can be discharged to the absorption circuit 2 through the diode D2, which reduces the stress on the switch S2 and improves the temperature rise of the switch S2. The difference is also that when the switch S1 is turned off in the fourth stage, the voltage stress increases. The voltage stress can be discharged to the absorption circuit 2 through the diode D3, which reduces the stress on the switch S1 and improves the temperature rise of the switch S1.

[0058] The above are merely preferred embodiments of this utility model. It should be noted that the above preferred embodiments should not be considered as limitations on this utility model. For those skilled in the art, several improvements and modifications can be made without departing from the spirit and scope of this utility model, and these improvements and modifications should also be considered within the protection scope of this utility model. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on this utility model.

Claims

1. A diode driving circuit, characterized in that: The invention comprises a current control circuit and a fast driving circuit; the current control circuit comprises a diode D1, a laser diode LD, a switch tube S1, a resistor R1, and a first control circuit; the fast driving circuit comprises an inductor L1, a diode D2, a switch tube S2, a resistor R2, and a second control circuit; the anode of the diode D1 and one end of the inductor L1 are electrically connected together and then connected to an input voltage Vin, the cathode of the diode D1, the cathode of the diode D2, and the anode of the laser diode LD are electrically connected together, the cathode of the laser diode LD and the second end of the switch tube S1 are electrically connected, the first end of the switch tube S1 and the third end of the first control circuit are electrically connected. The first end of the first control circuit is electrically connected to the third end of the switch tube S1, one end of the resistor R1, and the second end of the first control circuit are electrically connected together, the other end of the resistor R1 is electrically connected to the ground GND, the first end of the first control circuit is used to access the first control signal, the other end of the inductor L1, the anode of the diode D2, and the second end of the switch tube S2 are electrically connected together, the first end of the switch tube S2 is electrically connected to the third end of the second control circuit, the third end of the switch tube S2, one end of the resistor R2, and the second end of the second control circuit are electrically connected together, the other end of the resistor R2 is electrically connected to the ground GND, and the first end of the second control circuit is used to access the second control signal.

2. The diode driving circuit according to claim 1, characterized in that: It also includes a second absorption circuit, a first end of which is electrically connected to the cathode of the diode D1, the cathode of the diode D2, and the anode of the laser diode LD, and a second end of which is connected to the anode of the diode D1 and one end of the inductor L1.

3. The diode driving circuit according to claim 1, characterized in that: It also includes a second absorption circuit, a first end of the second absorption circuit is electrically connected to the cathode of the diode D1, the cathode of the diode D2, and the anode of the laser diode LD, and a second end of the second absorption circuit is grounded GND.

4. The diode driving circuit according to claim 2 or 3, characterized in that: The device further comprises a first absorption circuit, wherein the first absorption circuit comprises a diode D3, and the diode D3 is connected in reverse parallel with the laser diode LD.

5. The diode driving circuit according to claim 4, characterized in that: The second absorption circuit includes a resistor R3 and a capacitor C1; one end of the resistor R3 is the second end of the second absorption circuit, the other end of the resistor R3 is electrically connected to one end of the capacitor C1, and the other end of the capacitor C1 is the first end of the second absorption circuit.

6. The diode driving circuit according to claim 4, characterized in that: The second absorption circuit includes a diode TVS and a capacitor C1; the anode of the diode TVS is the second end of the second absorption circuit, the cathode of the diode TVS is electrically connected to one end of the capacitor C1, and the other end of the capacitor C1 is the first end of the second absorption circuit.

7. The diode driving circuit according to claim 4, characterized in that: The second absorption circuit includes a resistor R3 and a diode D4; one end of the resistor R3 is the second end of the second absorption circuit, the other end of the resistor R3 is electrically connected to the cathode of the diode D4, and the anode of the diode D4 is the first end of the second absorption circuit.

8. The diode driving circuit according to claim 5 or 7, characterized in that: The resistor R3 is a varistor or an adjustable resistor.

9. A diode driving circuit according to claim 4, characterized in that: The second absorption circuit includes a diode TVS and a diode D4; the anode of the diode TVS is the second end of the second absorption circuit, the cathode of the diode TVS is electrically connected to the cathode of the diode D4, and the anode of the diode D4 is the first end of the second absorption circuit.

10. The diode driving circuit according to claim 3, characterized in that: The second absorption circuit includes a diode TVS; the anode of the diode TVS is the second end of the second absorption circuit, and the cathode of the diode TVS is the first end of the second absorption circuit.

11. A diode driving circuit according to claim 3, characterized in that: The second absorption circuit includes a resistor RV; one end of the varistor RV is the first end of the second absorption circuit, and the other end of the resistor RV is the second end of the second absorption circuit.

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