Wide-voltage power supply circuit suitable for laser range finder

Abstract

The utility model relates to a wide-voltage power supply circuit suitable for a laser range finder, which is applied to the laser range finder and comprises a power supply input protection circuit, a voltage conversion circuit and an output filter circuit. The power input protection circuit is connected with an input power supply and the voltage conversion circuit. The voltage conversion circuit is connected with the filter circuit. According to the technical scheme, the voltage conversion circuit comprises a step-down transformer, a first inductor, an input port capacitor, an output port capacitor, an auxiliary power supply capacitor, a first capacitor, a second capacitor, a first resistor, a second resistor, a third resistor and a fourth resistor. According to the voltage conversion circuit in the technical scheme, the minimum input voltage is set by adjusting the resistance values of the first resistor and the second resistor, and the VSEL pin of the step-down transformer is used for switching between the two preset output voltages, so that when the input voltage is 2-16V, no matter whether the output voltage is higher than, lower than or equal to the input voltage, the output voltage can be switched between the two preset output voltages. 2.5-9V voltage can be effectively output, and a buck mode and a boost mode can be automatically switched.

Description

Technical Field

[0001] This application relates to the technical field of wide-voltage power supply, and particularly to a wide-voltage power supply circuit applicable to a laser rangefinder. Background Art

[0002] Due to many reasons such as high noise and unstable voltage, the external power supply of the laser rangefinder cannot be directly connected to the internal circuit of the laser rangefinder. Therefore, an input power supply circuit is required between the external power supply of the laser rangefinder and the internal circuit to convert the external power supply. The commonly used power supply circuits in the prior art are BUCK (step-down) and BOOST (step-up). These two power supply circuits can only perform single step-up or step-down of the input voltage. However, when the input voltage is 3.3V and 12V and the output requires 5V, the above two circuits cannot meet the requirements simultaneously. Utility Model Content

[0003] To overcome at least to some extent the problem that the power supply circuit of the laser rangefinder in the related art can only perform single step-up or step-down of the input voltage, this application provides a wide-voltage power supply circuit applicable to a laser rangefinder.

[0004] The solution of this application is as follows:

[0005] A wide-voltage power supply circuit applicable to a laser rangefinder, applied to a laser rangefinder, includes:

[0006] A power input protection circuit, a voltage conversion circuit, and an output filtering circuit;

[0007] The power input protection circuit is connected to the input power supply and the voltage conversion circuit, and is used to output the 2 - 16V input power supply to the voltage conversion circuit;

[0008] The voltage conversion circuit is connected to the filtering circuit, and is used to convert the 2 - 16V power supply to a 2.5 - 9V power supply and output it to the filtering circuit;

[0009] The voltage conversion circuit includes: a step-down transformer, a first inductor, an input port capacitor, an output port capacitor, an auxiliary power supply capacitor, a first capacitor, a second capacitor, a first resistor, a second resistor, a third resistor, and a fourth resistor;

[0010] The inductance pin of the step-down transformer is connected to the first inductor;

[0011] The VIN pin of the step-down transformer is connected to the input port capacitor, the first capacitor, and the output end of the power input protection circuit;

[0012] The VOUT pin of the step-down transformer is connected to the output port capacitor, the second capacitor, and the input end of the output filtering circuit;

[0013] The VAUX pin of the step-down transformer is grounded after being connected to the auxiliary power supply capacitor;

[0014] The EN pin and the PS / SYNC pin of the step-down transformer are connected to the output terminal of the power input protection circuit through the third resistor;

[0015] The first resistor is connected in parallel between the VOUT pin and the first FB pin of the step-down transformer;

[0016] The first resistor is grounded after being connected to the second resistor;

[0017] The fourth resistor is connected in parallel between the VOUT pin and the PG pin of the step-down transformer;

[0018] The VSEL pin, the second FB pin, the PGND pin and the GND pin of the step-down transformer are grounded.

[0019] Preferably, the input port capacitor is close to the output terminal of the power input protection circuit, and the first capacitor is close to the VIN pin of the step-down transformer.

[0020] Preferably, the output port capacitor is close to the input terminal of the output filtering circuit, and the second capacitor is close to the VOUT pin of the step-down transformer.

[0021] Preferably, the power input protection circuit includes:

[0022] A bridge rectifier, a fuse, a surge protection diode and a decoupling circuit;

[0023] The first port of the bridge rectifier is connected to the input power supply; the second port is connected to the decoupling circuit through the fuse; the third port is connected to the first end of the surge protection diode; the fourth port is grounded;

[0024] The second end of the surge protection diode is connected to the decoupling circuit;

[0025] The decoupling circuit is connected to the voltage conversion circuit.

[0026] Preferably, the decoupling circuit includes the third capacitor, the fourth capacitor, the fifth capacitor, the sixth capacitor, the seventh capacitor and the eighth capacitor connected in parallel.

[0027] Preferably, the third port of the bridge rectifier is grounded;

[0028] The decoupling circuit is grounded.

[0029] Preferably, the output filtering circuit includes:

[0030] The ninth capacitor, the tenth capacitor, the eleventh capacitor, the twelfth capacitor, the thirteenth capacitor, and the second inductor;

[0031] The ninth capacitor, the tenth capacitor, the eleventh capacitor, the twelfth capacitor, and the thirteenth capacitor are connected in parallel;

[0032] The second inductor is connected in series between the eleventh capacitor and the twelfth capacitor.

[0033] The technical solution provided by this application may include the following beneficial effects:

[0034] The wide-voltage power supply circuit applicable to a laser rangefinder in this application is applied to a laser rangefinder and includes: a power input protection circuit, a voltage conversion circuit, and an output filtering circuit. The power input protection circuit is connected to the input power supply and the voltage conversion circuit and is used to output a 2-16V input power supply to the voltage conversion circuit; the voltage conversion circuit is connected to the filtering circuit and is used to convert a 2-16V power supply to a 2.5-9V power supply and output it to the filtering circuit. The main improvement point of this technical solution is the voltage conversion circuit, and the voltage conversion circuit includes: a buck transformer, a first inductor, an input port capacitor, an output port capacitor, an auxiliary power supply capacitor, a first capacitor, a second capacitor, a first resistor, a second resistor, a third resistor, and a fourth resistor.

[0035] Among them, the inductance pin of the buck transformer is connected to the first inductor; the VIN pin of the buck transformer is connected to the input port capacitor, the first capacitor, and the output end of the power input protection circuit; the VOUT pin of the buck transformer is connected to the output port capacitor, the second capacitor, and the input end of the output filtering circuit; the VAUX pin of the buck transformer is grounded after being connected to the auxiliary power supply capacitor; the EN pin and the PS / SYNC pin of the buck transformer are connected to the output end of the power input protection circuit through the third resistor; a first resistor is connected in parallel between the VOUT pin and the first FB pin of the buck transformer; the first resistor is connected to the second resistor and then grounded; a fourth resistor is connected in parallel between the VOUT pin and the PG pin of the buck transformer; the VSEL pin, the second FB pin, the PGND pin, and the GND pin of the buck transformer are grounded.

[0036] In the voltage conversion circuit of this technical solution, the input minimum voltage is set by adjusting the resistance values of the first resistor and the second resistor. The VSEL pin of the buck transformer is used to switch between two preset output voltages; the EN pin is the enable control pin, which can be directly pulled high to make the circuit work continuously during power supply; the PS / SYNC pin has two functions to realize the switching between the PWM mode and the energy-saving mode of the buck transformer; the PG pin functions as an open-drain output. The overall voltage conversion circuit can effectively output a voltage of 2.5 - 9V when the input voltage is 2 - 16V, regardless of whether the output voltage is higher than, lower than, or equal to the input voltage. Its output current is up to 2A, and the buck mode and the boost mode can be automatically switched, with high voltage conversion efficiency.

[0037] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit this application. Brief Description of the Drawings

[0038] The drawings herein are incorporated into the specification and constitute a part of this specification, showing embodiments consistent with this application, and are used together with the specification to explain the principles of this application.

[0039] Figure 1 is a schematic circuit diagram of a voltage conversion circuit provided by an embodiment of this application;

[0040] Figure 2 is a schematic circuit diagram of a power input protection circuit provided by an embodiment of this application;

[0041] Figure 3 is a schematic circuit diagram of an output filter circuit provided by an embodiment of this application.

[0042] Reference Numerals: First Inductor - L1; Input Port Capacitor - CIN; Output Port Capacitor - COUT; Auxiliary Power Supply Capacitor - CVAUX; First Capacitor - C1; Second Capacitor - C2; First Resistor - R1; Second Resistor - R2; Third Resistor - R3; Fourth Resistor - R4; Bridge Rectifier - D1; Fuse - F1; Surge Protection Diode - D2; Third Capacitor - C3; Fourth Capacitor - C4; Fifth Capacitor - C5; Sixth Capacitor - C6; Seventh Capacitor - C7; Eighth Capacitor - C8; Ninth Capacitor - C9; Tenth Capacitor - C10; Eleventh Capacitor - C11; Twelfth Capacitor - C12; Thirteenth Capacitor - C13; Second Inductor - L2. Detailed Description of the Embodiments

[0043] Exemplary embodiments will be described in detail herein, and examples thereof are shown in the accompanying drawings. When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0044] A wide-voltage power supply circuit applicable to a laser rangefinder is applied to a laser rangefinder. Refer to Figure 1 , and includes:

[0045] A power input protection circuit, a voltage conversion circuit, and an output filtering circuit;

[0046] The power input protection circuit is connected to the input power supply and the voltage conversion circuit, and is used to output a 2-16V input power supply to the voltage conversion circuit;

[0047] The voltage conversion circuit is connected to the filtering circuit, and is used to convert a 2-16V power supply to a 2.5-9V power supply and output it to the filtering circuit;

[0048] The voltage conversion circuit includes: a buck transformer, a first inductor L1, an input port capacitor CIN, an output port capacitor COUT, an auxiliary power supply capacitor CVAUX, a first capacitor C1, a second capacitor C2, a first resistor R1, a second resistor R2, a third resistor R3, and a fourth resistor R4;

[0049] The inductance pin of the buck transformer is connected to the first inductor L1;

[0050] The VIN pin of the buck transformer is connected to the input port capacitor CIN, the first capacitor C1, and the output end of the power input protection circuit;

[0051] The VOUT pin of the buck transformer is connected to the output port capacitor COUT, the second capacitor C2, and the input end of the output filtering circuit;

[0052] The VAUX pin of the buck transformer is grounded after being connected to the auxiliary power supply capacitor CVAUX;

[0053] The EN pin and the PS / SYNC pin of the buck transformer are connected to the output end of the power input protection circuit through the third resistor R3;

[0054] A first resistor R1 is connected in parallel between the VOUT pin of the buck transformer and the first FB pin;

[0055] The first resistor R1 is grounded after being connected to the second resistor R2;

[0056] A fourth resistor R4 is connected in parallel between the VOUT pin of the buck transformer and the PG pin;

[0057] The VSEL pin, the second FB pin, the PGND pin, and the GND pin of the step-down transformer are grounded.

[0058] In specific practice, the TPS63070 chip can be selected for the step-down transformer. Refer to Figure 1 , TPS63070 is a voltage converter with high efficiency and low quiescent current, suitable for applications where the input voltage is higher or lower than the output voltage.

[0059] The pins of the TPS63070 chip are described as follows:

[0060] VIN is the input pin; VOUT is the output pin;

[0061] The VSEL pin is used to switch between two preset output voltages;

[0062] The EN pin is the enable control pin. It can be directly pulled high to keep the circuit working when powered on; or it can be controlled through an external control interface to work or not work when continuously powered on.

[0063] The PS / SYNC pin has two functions to realize the switching between the PWM mode and the energy-saving mode of the step-down transformer;

[0064] The PG pin functions as an open-drain output;

[0065] The PGND pin is the grounding pin of the PG pin

[0066] The VAUX pin is the auxiliary power supply pin;

[0067] The voltage of the FB pin is fixed at 0.8V. The minimum input voltage can be set by adjusting the resistance values of the first resistor R1 and the second resistor R2. The calculation formula is VIN+≥0.8R2 / R3+0.8V;

[0068] The FB pin is the grounding pin of the FB pin.

[0069] The overall voltage conversion circuit can effectively output a voltage of 2.5 - 9V with a maximum output current of 2A when the input voltage is 2 - 16V, regardless of whether the output voltage is higher than, lower than, or equal to the input voltage, through the above circuit design. Moreover, the step-down mode and the boost mode can be automatically switched, and the voltage conversion efficiency is high.

[0070] It should be noted that, referring to Figure 1 , the input port capacitor CIN is close to the output end of the power input protection circuit, and the first capacitor C1 is close to the VIN pin of the step-down transformer.

[0071] Refer to Figure 1, the output port capacitor COUT is close to the input end of the output filter circuit, and the second capacitor C2 is close to the VOUT pin of the buck transformer.

[0072] Refer to Figure 2 , the power input protection circuit includes:

[0073] a bridge rectifier D1, a fuse F1, a surge protection diode D2, and a decoupling circuit;

[0074] The first port of the bridge rectifier D1 is connected to the input power supply; the second port is connected to the decoupling circuit through the fuse F1; the third port is connected to the first end of the surge protection diode D2; the fourth port is grounded;

[0075] The second end of the surge protection diode D2 is connected to the decoupling circuit;

[0076] The decoupling circuit is connected to the voltage conversion circuit.

[0077] In specific practice, when the laser rangefinder is powered on and working, VIN+ first passes through the bridge rectifier D1, then through the fuse F1, then through the surge protection diode D2, and finally through the decoupling circuit and enters the voltage conversion circuit as VIN.

[0078] Refer to Figure 2 , the decoupling circuit includes a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5, a sixth capacitor C6, a seventh capacitor C7, and an eighth capacitor C8 connected in parallel.

[0079] Refer to Figure 2 , the third port of the bridge rectifier D1 is grounded;

[0080] The decoupling circuit is grounded.

[0081] Refer to Figure 3 , the output filter circuit includes:

[0082] a ninth capacitor C9, a tenth capacitor C10, an eleventh capacitor C11, a twelfth capacitor C12, a thirteenth capacitor C13, and a second inductor L2;

[0083] The ninth capacitor C9, the tenth capacitor C10, the eleventh capacitor C11, the twelfth capacitor C12, and the thirteenth capacitor C13 are connected in parallel;

[0084] The second inductor L2 is connected in series between the eleventh capacitor C11 and the twelfth capacitor C12.

[0085] Refer to Figure 3 , the voltage conversion circuit converts VIN into Vout and outputs it to the output filter circuit, and Vout is output to the subsequent circuit with less noise after being filtered by the output filter circuit LC.

[0086] It has been proved by practice that the wide-voltage power supply circuit applicable to a laser rangefinder in the present technical solution, when applied to a laser rangefinder and tested under various extreme environmental conditions, can stably output a voltage of 2.5 - 9V when the supply voltage is 3 - 16V, the output current reaches 2A, and the voltage conversion efficiency is as high as 95%.

[0087] It can be understood that the same or similar parts in the above embodiments can be referred to each other, and the content not detailed in some embodiments can be seen in the same or similar content of other embodiments.

[0088] It should be noted that in the description of the present application, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present application, unless otherwise specified, the meaning of "a plurality of" refers to at least two.

[0089] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0090] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A wide-voltage power supply circuit applicable to a laser rangefinder, which is applied to the laser rangefinder, and is characterized in that, It includes: a power input protection circuit, a voltage conversion circuit, and an output filtering circuit; The power input protection circuit is connected to the input power supply and the voltage conversion circuit, and is used to output a 2 - 16V input power supply to the voltage conversion circuit; The voltage conversion circuit is connected to the filtering circuit, and is used to convert a 2 - 16V power supply to a 2.5 - 9V power supply and output it to the filtering circuit; The voltage conversion circuit includes: a buck transformer, a first inductor, an input port capacitor, an output port capacitor, an auxiliary power supply capacitor, a first capacitor, a second capacitor, a first resistor, a second resistor, a third resistor, and a fourth resistor; The inductance pin of the buck transformer is connected to the first inductor; The VIN pin of the buck transformer is connected to the input port capacitor, the first capacitor, and the output end of the power input protection circuit; The VOUT pin of the buck transformer is connected to the output port capacitor, the second capacitor, and the input end of the output filtering circuit; The VAUX pin of the buck transformer is grounded after being connected to the auxiliary power supply capacitor; The EN pin and the PS / SYNC pin of the buck transformer are connected to the output end of the power input protection circuit through the third resistor; The first resistor is connected in parallel between the VOUT pin and the first FB pin of the buck transformer; The first resistor is grounded after being connected to the second resistor; The fourth resistor is connected in parallel between the VOUT pin and the PG pin of the buck transformer; The VSEL pin, the second FB pin, the PGND pin, and the GND pin of the buck transformer are grounded.

2. The wide-voltage power supply circuit applicable to a laser rangefinder according to claim 1, wherein The input port capacitor is close to the output end of the power input protection circuit, and the first capacitor is close to the VIN pin of the buck transformer.

3. The wide-voltage power supply circuit applicable to a laser rangefinder according to claim 1, wherein The output port capacitor is close to the input end of the output filtering circuit, and the second capacitor is close to the VOUT pin of the buck transformer.

4. The wide-voltage power supply circuit applicable to a laser rangefinder according to claim 1, wherein, The power input protection circuit includes: a bridge rectifier, a fuse, a surge protection diode, and a decoupling circuit; The first port of the bridge rectifier is connected to the input power supply; the second port is connected to the decoupling circuit through the fuse; the third port is connected to the first end of the surge protection diode; the fourth port is grounded; The second end of the surge protection diode is connected to the decoupling circuit; The decoupling circuit is connected to the voltage conversion circuit.

5. The wide-voltage power supply circuit applicable to a laser rangefinder according to claim 4, characterized in that, The decoupling circuit includes the third capacitor, the fourth capacitor, the fifth capacitor, the sixth capacitor, the seventh capacitor, and the eighth capacitor connected in parallel.

6. The wide-voltage power supply circuit applicable to a laser rangefinder according to claim 5, characterized in that, The third port of the bridge rectifier is grounded; The decoupling circuit is grounded.

7. The wide-voltage power supply circuit applicable to a laser rangefinder according to claim 1, characterized in that, The output filtering circuit includes: a ninth capacitor, a tenth capacitor, an eleventh capacitor, a twelfth capacitor, a thirteenth capacitor, and a second inductor; The ninth capacitor, the tenth capacitor, the eleventh capacitor, the twelfth capacitor, and the thirteenth capacitor are connected in parallel; The second inductor is connected in series between the eleventh capacitor and the twelfth capacitor.

Images