CN216981788U - PWM power supply capable of adjusting current - Google Patents

Abstract

The utility model belongs to the technical field of power supplies, and discloses a PWM power supply capable of adjusting current, which comprises a main control MCU, a driving circuit, an MOS tube, a current and voltage acquisition chip, an AC-DC conversion module and an adjustable power supply; the main control MCU generates 4 paths of PWM signals through a timer peripheral, controls the drive circuit to enable the MOS tube to be switched on and off, and outputs 4 paths of PWM power supply signals; the main control MCU also generates two paths of analog quantity signals, and the alternating current is converted into direct current through the AC-DC conversion module; the adjustable power supply is connected with the main control MCU and converts direct current into a +/-15V power supply and a 3.3V power supply; the current and voltage acquisition chip acquires the current and the voltage of the PWM power supply signal and sends the current and the voltage to the main control MCU through an I2C bus. The utility model can remotely control or manually adjust the size of the PWM signal; and a digital circuit is adopted to produce PWM signals, so that the accuracy of signal duty ratio regulation is higher.

Description

PWM power supply capable of adjusting current

Technical Field

The utility model belongs to the technical field of power supplies, and particularly relates to a PWM power supply capable of adjusting current.

Background

During the testing process of the LED lamp on the tested product, various performances of the LED lamp need to be tested. Such as brightness level, power consumption, etc.; the conventional test method of the LED is to adjust the brightness by changing the current in a loop, but the adjustable current range is limited by hardware, the number of adjusting gears is small, and the method is not ideal for high-precision lighting equipment requiring brightness induction sensitivity.

At present, most of LED lamps are adjusted through analog dimming, and the brightness of an LED is adjusted by changing the current in an LED loop, so that the defect that the adjustable gear is limited within the adjustable current range is overcome; or the LED is switched on and off through the PWM wave to change the conducting time of the forward current so as to achieve the effect of brightness adjustment.

However, the common PWM adjustment has the problems that the setting of the duty ratio is not accurate enough, the current LED power consumption cannot be calculated, the load carrying capacity is not enough and the like, and the common PWM adjustment cannot be used in occasions with certain power requirements.

SUMMERY OF THE UTILITY MODEL

In view of this, the present invention provides a PWM power supply capable of adjusting the magnitude of current, so that the brightness level of the LED lamp can be adjusted in multiple stages, the power consumption of the LED lamp can be calculated, and the capability of simultaneously testing a plurality of LED lamps can be achieved, thereby saving the test period of the LED lamp on the tested product and providing the accuracy of the test.

The utility model discloses a PWM power supply capable of adjusting current, which comprises a main control MCU, a driving circuit, an MOS tube, a current and voltage acquisition chip, an AC-DC conversion module and an adjustable power supply, wherein the main control MCU is connected with the driving circuit;

the AC-DC conversion module is connected with commercial power, converts alternating current into direct current and supplies power to the main control MCU;

the main control MCU generates 4 paths of PWM signals through a built-in timer peripheral, controls a driving circuit to enable the MOS tube to be switched on and off, and outputs 4 paths of PWM power supply signals; the master control MCU is communicated with the upper computer through an RS485 interface and is set according to a PWM level value transmitted by the upper computer;

the adjustable power supply is connected with the main control MCU, and two paths of analog quantity signals additionally generated by the main control MCU are converted into a +/-15V power supply and a 3.3V power supply;

the current and voltage acquisition chip acquires the current and voltage of each path of PWM power supply signal and sends the current and voltage to the main control MCU through an I2C bus.

Further, the adjustable power supply includes a conversion chip U1, a fuse F1, an inductor L1, a voltage dependent resistor V1, a capacitor C2, a transformer L2, a capacitor C1, a capacitor C4, a capacitor C3, a capacitor CM1 and a diode D1, an L line of a 220V commercial power is connected to the fuse F1, the other end of the fuse F1 is connected to the inductor L1, the voltage dependent resistor V1 and the capacitor C2, the other end of the inductor L1 is connected to a 3 rd winding of the transformer L2, a 2 nd winding of the transformer L2 is connected to the other end of the voltage dependent resistor V1 and the other end of the capacitor C2, a 1 st winding of the transformer L2 is connected to the capacitor C4 and an N pin of the conversion chip U1, a 4 th winding of the transformer L2 is connected to the capacitor C1 and an L pin of the conversion chip U1, and the other end of the capacitor C1 is connected to the capacitor C4, the capacitor C3, the capacitor CM1 and the diode D1 are respectively connected in parallel between the VO + pin and the VO-pin of the conversion chip U1, and 15V voltage is output.

Further, the adjustable power supply further includes a conversion chip U2, the 1 st pin of the conversion chip U2 is connected to the 15V power supply output by the conversion chip U1, the 2 nd pin of the conversion chip U2 is connected to the resistor R2, and then connected to the 15V power supply output by the conversion chip U1, the 15V power supply output by the conversion chip U1 is further connected to the resistor R1, the other end of the resistor R1 is connected to the resistor R5 and the 3 rd pin of the conversion chip U2, the resistor R5 is connected in parallel to the capacitor C7 and the capacitor C8, the 4 th pin and the 8 th pin of the conversion chip U2 are grounded, the 5 th pin is connected to the capacitor C9, the other end of the capacitor C9 is grounded, the 6 th pin is connected to the capacitor C6, the resistor R3 and the resistor R6, the other end of the capacitor C6 is connected to the 3.3V power supply, the other end of the resistor R6 is grounded, the other end of the resistor R3 is connected to the capacitor C5475 and the capacitor C6474, the other end of the capacitor C10 is grounded, the other end of the capacitor C11 is grounded, and the 7 th pin of the conversion chip U2 is connected with a 3.3V power supply.

Further, the 3.3V power supply is connected to a 32 th pin, a 48 th pin, a 64 th pin, a 19 th pin of the main control MCU and an inductor L5, respectively, the other end of the inductor L5 is connected to a 13 th pin of the main control MCU and a capacitor C27, and the other end of the capacitor C27 is grounded;

the 41 th pin of the main control MCU is connected with a TIM1_ CH1 signal line, the 23 th pin is connected with a TIM1_ CH1N signal line, and a TIM1_ CH1 signal line and a TIM1_ CH1N signal line form a 1-path PWM signal PWM _ OUT 1;

the 16 th pin of the main control MCU is connected with a TIM2_ CH3 signal line, the 17 th pin is connected with a TIM2_ CH4 signal line, and a TIM1_ CH1 signal line and a TIM1_ CH1N signal line form a 1-path PWM signal PWM _ OUT 2;

the 26 th pin of the main control MCU is connected with a TIM3_ CH3 signal line, the 27 th pin is connected with a TIM3_ CH4 signal line, and a TIM3_ CH3 signal line and a TIM3_ CH4 signal line form a 1-path PWM signal PWM _ OUT 3;

the pin 61 of the main control MCU is connected with a TIM4_ CH3 signal line, the pin 62 is connected with a TIM4_ CH4 signal line, and a TIM4_ CH3 signal line and a TIM4_ CH4 signal line form a 1-path PWM signal PWM _ OUT 4.

Further, the 4-way PWM power signal includes a PWM1_ OUT signal line, a PWM2_ OUT signal line, a PWM3_ OUT signal line, and a PWM4_ OUT signal line.

Furthermore, the driving circuit comprises a first driving circuit, a second driving circuit, a third driving circuit and a fourth driving circuit, and the first driving circuit, the second driving circuit, the third driving circuit and the fourth driving circuit have the same structure; the inputs of the first driving circuit are the TIM1_ CH1 signal line and the TIM1_ CHIN signal line, the TIM1_ CH1 signal line is connected to the resistor R45, the TIM1_ CHIN signal line is connected to the resistor R47, the resistor R45 is connected to the pin 1 of the driving chip U19, the resistor R47 is connected to the pin 2 of the driving chip U19, the pin 3 of the driving chip U19 is connected to ground, the pin 5 is connected to the +15V power supply, the resistor R19 and the capacitor C19 respectively, the capacitor C19 is connected to ground, the resistor R19 is connected to the anode of the diode D19, the cathode of the diode D19 is connected to the pin 8 of the driving chip U19, the pin 8 of the driving chip U19 is further connected to the capacitor C19, the other end of the capacitor C19 is connected to the pin 6 of the driving chip U19, the pin 6 of the driving chip 19 is further connected to the pin 6 of the driving chip 19, the PWM chip U19, the pin 6 _ CHIN is connected to the pin 19, the signal line is connected to the PWM chip OUT 19, the pin 19, the resistor R19 is connected to the pin 19 and the pin 19, the driving chip R19, the other end of the diode and the other end of the resistor R41 are respectively connected with a capacitor C56 and the grid of a MOS tube Q4, the drain of the MOS tube Q4 is connected with a power supply VCC, and the source of the MOS tube Q4 and the other pole of the capacitor C56 are respectively connected with a PWM1_ OUT signal line; the 4 th pin of the driving chip U19 is respectively connected with a diode D8 and a resistor R49, the other end of the diode D8 and the other end of the resistor R49 are respectively connected with a grid electrode of a capacitor C60, a resistor R51 and a gate electrode of a MOS tube Q3, the other end of the capacitor C60, the other end of the resistor R51 and a source electrode of the MOS tube Q3 are respectively grounded, and a drain electrode of the MOS tube Q3 is connected with a PWM1_ OUT signal line.

Further, the current and voltage collecting chip comprises a chip U11 and a chip U13, a PWM _ OUT1 signal line is connected to a fuse F2 and then connected to a 4 th pin of the chip U11 and a resistor R21, the other end of the resistor R21 is connected to a PWM1_ OUT signal line and a 3 rd pin of the chip U11, the PWM1_ OUT signal line is further connected to a resistor R23, the other end of the resistor R23 is connected to a resistor R29 and a 1 st pin of the chip U13, and the other end of the resistor R29 is grounded; the 6 th pin of the chip U11 is respectively connected with a 3.3V power supply and a capacitor C42, and the other end of the capacitor C42 and the 2 nd pin of the chip U11 are grounded; the 1 st pin of the chip U11 is connected to the resistor R27, the other end of the resistor R27 is connected to the capacitor C44 and the 4 th pin of the chip U13, the 2 nd pin, the 3 rd pin, the 5 th pin, the 9 th pin and the 10 th pin of the chip U13 are grounded, the 7 th pin is connected to the resistor R24 and the I2C1_ SDA signal line, the other end of the resistor R24 is connected to the resistor R25, the other end of the resistor R25 is connected to the I2C1_ SCL signal line, the 8 th pin of the chip U13 is connected to the I2C1_ SCL signal line, the 6 th pin is connected to the capacitor C46 and the capacitor CM6, the I2C1_ SDA signal line is connected to the 59 th pin of the main control MCU, and the I2C1_ SCL signal line is connected to the 58 th pin of the main control MCU.

Further, the chip of the main control MCU is STM32F103RBT6, and the 50 th pin of the chip is connected with an upper computer.

The utility model has the following beneficial effects:

the size of the PWM signal can be remotely controlled and manually adjusted, and the PWM signal can be conveniently used in different occasions;

a digital circuit is adopted to produce PWM signals, so that the accuracy of signal duty ratio regulation is high; meanwhile, various protection circuits are integrated inside the protective circuit for overvoltage and overcurrent protection.

Drawings

FIG. 1 is a logical block diagram of the modules of the present invention;

FIG. 2 is a schematic diagram of a master MCU board according to the present invention;

FIG. 3 is a circuit diagram of a portion one of the adjustable power supply of the present invention;

FIG. 4 is a circuit diagram of part two of the adjustable power supply of the present invention;

FIG. 5 is a circuit diagram of the drive circuit of the present invention;

FIG. 6 is a circuit diagram of the current and voltage acquisition chip of the present invention;

FIG. 7 is a circuit diagram of a master MCU of the present invention;

FIG. 8 is a circuit diagram of an LCD panel according to the present invention;

FIG. 9 is a wiring diagram of the power supply of the present invention;

FIG. 10 is a line drawing of XP2 of the present invention;

FIG. 11 is a wiring diagram of XP3 of the present invention;

FIG. 12 is a schematic diagram of a power supply panel of the present invention.

Detailed Description

The utility model is further described with reference to the accompanying drawings, but the utility model is not limited in any way, and any alterations or substitutions based on the teaching of the utility model are within the scope of the utility model.

The PWM power supply disclosed by the embodiment integrates various resources required by PWM generation, and the external power supply can be directly used only by being connected with a 220V power supply; the PWM signal mode is integrated by program control and manual regulation, and the device is convenient to use in different occasions; a digital circuit is adopted to produce PWM signals, so that the accuracy of signal duty ratio regulation is high; meanwhile, various protection circuits are integrated inside the protective circuit for overvoltage and overcurrent protection.

The PWM power supply of this embodiment includes that main control board, button knob, LCD screen, adjustable power and quick-witted case are constituteed, and quick-witted incasement portion mainly contains adjustable power and main control board, simple structure simple to operate, and the later stage can carry out the function extension as required.

The main control board realizes PWM signal setting through serial ports and host computer communication, and button and LCD screen make things convenient for operating personnel to carry out manual regulation on the panel, and adjustable power adjusts the high level size of PWM signal. The logic diagram of the cross-linking of the modules is shown in fig. 1.

The master control MCU provides 4 paths of independent PWM signals for the self-made small plate. The main control MCU selects STM32F103RBT6, is small and exquisite in size and rich in functions, generates 4 paths of PWM signals through a built-in timer peripheral, controls a half-bridge driving chip IRS2186 to enable the MOS tube to be switched on and off, and achieves the switching output of an adjustable power supply; meanwhile, the current of each path of signal is collected through a current collection chip LMP8640, the signal voltage is collected through a voltage collection chip, and the signal voltage is sent to the MCU through an I2C bus; the on-board power supply provides a 15V power supply through the AC-DC conversion module, and the power supply is converted into a required 3.3V power supply through the power supply chip. The principle schematic diagram of the main control board is shown in fig. 2.

The 3.3V power supply is respectively connected with a 32 th pin, a 48 th pin, a 64 th pin, a 19 th pin and an inductor L5 of the master control MCU, the other end of the inductor L5 is respectively connected with a 13 th pin of the master control MCU and a capacitor C27, and the other end of the capacitor C27 is grounded;

the adjustable power supply converts 220V commercial power into 3.3V and +/-15V power supplies required by working on the board; the 220V conversion part is added with a protection circuit, and the protection of the circuit on the board is realized by a fuse, a piezoresistor, a safety capacitor and the like.

As shown in fig. 3, the adjustable power supply includes a conversion chip U1, a fuse F1, an inductor L1, a voltage-dependent resistor V1, a capacitor C1, a transformer L1, a capacitor C1, a capacitor CM1 and a diode D1, the L line of the 220V mains is connected to the fuse F1, the other end of the fuse F1 is connected to the inductor L1, the voltage-dependent resistor V1 and the capacitor C1, respectively, the other end of the inductor L1 is connected to the 3 rd winding of the transformer L1, the 2 nd winding of the transformer L1 is connected to the other end of the voltage-dependent resistor V1 and the other end of the capacitor C1, the 1 st winding of the transformer L1 is connected to the capacitor C1 and the N pin of the conversion chip U1, the 4 th winding of the transformer L1 is connected to the capacitor C1, the L pin of the conversion chip U4, the other end of the capacitor C1 is connected to the other end of the capacitor C1, the VO and the capacitor C1, the VO, the diode C1 are connected in parallel, and outputs a voltage of 15V.

As shown in fig. 4, the adjustable power supply further includes a conversion chip U2, configured to convert a 15V power supply into a 3.3V power supply, a pin 1 of the conversion chip U2 is connected to the 15V power supply output by the conversion chip U1, a pin 2 of the conversion chip U2 is connected to a resistor R2, and then is connected to the 15V power supply output by the conversion chip U1, the 15V power supply output by the conversion chip U1 is further connected to a resistor R1, another end of the resistor R1 is connected to a resistor R5 and a pin 3 of the conversion chip U2, the resistor R5 is connected in parallel to a capacitor C7 and a capacitor C8, a pin 4 and a pin 8 of the conversion chip U2 are grounded, a pin 5 is connected to a capacitor C9, another end of the capacitor C9 is grounded, a pin 6 is connected to a capacitor C6, a resistor R3 and a resistor R6, another end of the capacitor C6 is connected to the 3.3V power supply, another end of the resistor R6 is grounded, another end of the resistor R3 is connected to a capacitor C11 and a capacitor C11, the other end of the capacitor C10 is grounded, the other end of the capacitor C11 is grounded, and the 7 th pin of the conversion chip U2 is connected with a 3.3V power supply.

The driving circuit drives the PWM signal output by the main control MCU, so that the driving circuit has larger loading capacity. The driving circuit comprises a first driving circuit, a second driving circuit, a third driving circuit and a fourth driving circuit, and the first driving circuit, the second driving circuit, the third driving circuit and the fourth driving circuit have the same structure. In this embodiment, only the first driving circuit is described in detail, and other driving circuits are not described again.

As shown in FIG. 5, the inputs of the first driver circuit are the TIM1_ CH1 signal line and the TIM1_ CHIN signal line, the TIM1_ CH1 signal line is connected to the R1, the TIM1_ CHIN signal line is connected to the R1, the other terminal of the R1 is connected to the 1 st pin of the driver U1, the other terminal of the R1 is connected to the 2 nd pin of the driver U1, the 3 rd pin of the driver U1 is connected to ground, the 5 th pin is connected to +15V power supply, the R1 and the C1 capacitor, the other terminal of the C1 capacitor is connected to ground, the other terminal of the R1 is connected to the positive terminal of the diode D1, the negative terminal of the diode D1 is connected to the 8 th pin of the driver U1, the 8 th pin of the driver U1 is connected to the C1 capacitor, the other terminal of the C1 capacitor is connected to the 6 th pin of the driver U1, the 6 th pin of the driver U1 is connected to the OUT 6 th pin of the driver U1, the other terminal of the U1 is connected to the OUT4, the other terminal of the PWM chip, the R1 and the other terminal of the R1 and the resistor 1 of the resistor 1 is connected to the PWM chip is connected to the Q1 of the resistor 1, the resistor 1 of the resistor 1 is connected to the second terminal of the resistor 1, the Q1 of the transistor is connected to the resistor R1 of the resistor 1, the second terminal of the transistor is connected to the resistor 1 of the R1 of the resistor 1 and the transistor is connected to the resistor 1 of the resistor 1, the second terminal of the R1 of the resistor D1 of the resistor 1, the drain electrode of the MOS tube Q4 is connected with a power supply VCC, and the source electrode of the MOS tube Q4 and the other electrode of the capacitor C56 are respectively connected with a PWM1_ OUT signal wire; the 4 th pin of the driving chip U19 is connected with a diode D8 and a resistor R49 respectively, the other end of the diode D8 and the other end of the resistor R49 are connected with a grid electrode of a capacitor C60, a resistor R51 and a MOS tube Q3 respectively, the other end of the capacitor C60, the other end of the resistor R51 and a source electrode of the MOS tube Q3 are grounded respectively, and a drain electrode of the MOS tube Q3 is connected with a PWM1_ OUT signal line.

As shown in fig. 6, the current and voltage acquisition chip respectively performs voltage and current detection on the 4 paths of PWM signals, and the signals are acquired by the main control MCU. The current and voltage acquisition chip comprises a chip U11 and a chip U13, a PWM _ OUT1 signal line is connected with a fuse F2 and then is respectively connected with a 4 th pin of the chip U11 and a resistor R21, the other end of the resistor R21 is respectively connected with a PWM1_ OUT signal line and a 3 rd pin of the chip U11, a PWM1_ OUT signal line is also connected with a resistor R23, the other end of the resistor R23 is respectively connected with a resistor R29 and a 1 st pin of the chip U13, and the other end of the resistor R29 is grounded; the 6 th pin of the chip U11 is respectively connected with a 3.3V power supply and a capacitor C42, and the other end of the capacitor C42 and the 2 nd pin of the chip U11 are grounded; pin 1 of a chip U11 is connected to a resistor R27, the other end of the resistor R27 is connected to pin 4 of a capacitor C44 and a chip U13, pin 2, pin 3, pin 5, pin 9 and pin 10 of a chip U13 are grounded, pin 7 is connected to a resistor R24 and an I2C1_ SDA signal line, the other end of the resistor R24 is connected to a resistor R25, the other end of the resistor R25 is connected to an I2C1_ SCL signal line, pin 8 of a chip U13 is connected to an I2C1_ SCL signal line, pin 6 is connected to a capacitor C46 and a capacitor CM6, an I2C1_ SDA signal line is connected to pin 59 of a main control MCU, and an I2C1_ SCL signal line is connected to pin 58 of the main control MCU.

The master control MCU generates 4 paths of PWM signals and 2 paths of analog quantity signals, and controls the keys of the panel and the display of the liquid crystal screen, so that an operator can conveniently perform manual button operation and check parameter information on the liquid crystal screen in real time. Fig. 7 shows a circuit diagram of the master MCU, a chip of the master MCU is STM32F103RBT6, and a 50 th pin of the chip is connected to an upper computer.

The 41 th pin of the master MCU is connected with a TIM1_ CH1 signal line, the 23 th pin is connected with a TIM1_ CH1N signal line, and a TIM1_ CH1 signal line and a TIM1_ CH1N signal line form a 1-path PWM signal PWM _ OUT 1;

the 16 th pin of the master MCU is connected with a TIM2_ CH3 signal line, the 17 th pin is connected with a TIM2_ CH4 signal line, and a TIM1_ CH1 signal line and a TIM1_ CH1N signal line form a 1-path PWM signal PWM _ OUT 2;

the 26 th pin of the master MCU is connected with a TIM3_ CH3 signal line, the 27 th pin is connected with a TIM3_ CH4 signal line, and a TIM3_ CH3 signal line and a TIM3_ CH4 signal line form a 1-path PWM signal PWM _ OUT 3;

the pin 61 of the master MCU is connected to a TIM4_ CH3 signal line, the pin 62 is connected to a TIM4_ CH4 signal line, and the TIM4_ CH3 signal line and the TIM4_ CH4 signal line form a 1-channel PWM signal PWM _ OUT 4.

Fig. 8 is a circuit diagram of the LCD panel, wherein the 1 st pin, the 6 th pin, the 5 th pin and the 2 nd pin of the chip U5 are respectively connected to the 33 rd pin, the 34 th pin, the 36 th pin and the 35 th pin of the main control MCU.

The internal wiring diagram of the PWM power supply of the present invention is shown in fig. 9. The XP1 is a plug-in 3-core wiring terminal, the XP2 is a welding wire type DB15 double-row pin, and the XP3 is a welding wire type DB15 double-row pin.

As shown in fig. 10, the 1 st and 9 th pins of the XP2 are connected to a Vin power supply, the 2 nd, 10 th, 11 th and 12 th pins are grounded, the 3 rd pin is connected to the VOL _ SIG1, the 4 th pin is connected to the VOL _ SIG2, the 6 th pin is connected to an RS232 signal transmitting terminal, the 7 th pin is connected to an RS232 signal receiving terminal, the 14 th pin is connected to an RS485 signal D + terminal, and the 15 th pin is connected to an RS485 signal D-terminal.

As shown in fig. 11, the 1 st and 9 th pins of XP3 are connected to a PWM _ OUT1 signal line, the 2 nd, 4 th, 6 th, 8 th, 10 th, 12 th and 14 th pins are grounded, the 3 rd and 11 th pins are connected to a PWM _ OUT2 signal line, the 5 th and 13 th pins are connected to a PWM _ OUT3 signal line, and the 7 th and 15 th pins are connected to a PWM _ OUT4 signal line.

The appearance diagram of the PWM power supply of the present invention is shown in fig. 12, and includes a 220V power switch, which can turn on and off the 220V input power supply. The Adjust1 and Adjust2 switches can Adjust the high level of the PWM signal.

Other technologies not disclosed in the present invention, such as AD-DC module, knob on panel, button, etc., are prior art in this field and will not be described in detail.

The utility model has the following beneficial effects:

the size of the PWM signal can be remotely controlled and manually adjusted, and the PWM signal can be conveniently used in different occasions;

a digital circuit is adopted to produce PWM signals, so that the accuracy of signal duty ratio regulation is high; meanwhile, various protection circuits are integrated inside the protective circuit for overvoltage and overcurrent protection.

The word "preferred" is used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as "preferred" is not necessarily to be construed as advantageous over other aspects or designs. Rather, use of the word "preferred" is intended to present concepts in a concrete fashion. The term "or" as used in this application is intended to mean an inclusive "or" rather than an exclusive "or". That is, unless specified otherwise or clear from context, "X employs A or B" is intended to include either of the permutations as a matter of course. That is, if X employs A; b is used as X; or X employs both A and B, then "X employs A or B" is satisfied under any of the foregoing instances.

Also, although the disclosure has been shown and described with respect to one or an implementation, equivalent alterations and modifications will occur to others skilled in the art based upon a reading and understanding of this specification and the annexed drawings. The present disclosure includes all such modifications and alterations, and is limited only by the scope of the appended claims. In particular regard to the various functions performed by the above described components (e.g., elements, etc.), the terms used to describe such components are intended to correspond, unless otherwise indicated, to any component which performs the specified function of the described component (e.g., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary implementations of the disclosure. In addition, while a particular feature of the disclosure may have been disclosed with respect to only one of several implementations, such feature may be combined with one or other features of the other implementations as may be desired and advantageous for a given or particular application. Furthermore, to the extent that the terms "includes," has, "" contains, "or variants thereof are used in either the detailed description or the claims, such terms are intended to be inclusive in a manner similar to the term" comprising.

Each functional unit in the embodiments of the present invention may be integrated into one processing module, or each unit may exist alone physically, or a plurality of or more than one unit are integrated into one module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. The integrated module, if implemented in the form of a software functional module and sold or used as a stand-alone product, may also be stored in a computer readable storage medium. The storage medium mentioned above may be a read-only memory, a magnetic or optical disk, etc. Each apparatus or system described above may execute the storage method in the corresponding method embodiment.

In summary, the above-mentioned embodiment is an implementation manner of the present invention, but the implementation manner of the present invention is not limited by the above-mentioned embodiment, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be regarded as equivalent replacements within the protection scope of the present invention.

Claims (8)

1. A PWM power supply capable of adjusting current is characterized by comprising a main control MCU, a driving circuit, an MOS tube, a current and voltage acquisition chip, an AC-DC conversion module and an adjustable power supply;

the AC-DC conversion module is connected with commercial power, converts alternating current into direct current and supplies power to the main control MCU;

the main control MCU generates 4 paths of PWM signals through a built-in timer, controls a driving circuit to enable the MOS tube to be switched on and off, and outputs 4 paths of PWM power supply signals; the master control MCU is communicated with the upper computer through an RS485 interface and is set according to a PWM level value transmitted by the upper computer;

the adjustable power supply is connected with the main control MCU, and two paths of analog quantity signals additionally generated by the main control MCU are converted into a +/-15V power supply and a 3.3V power supply;

the current and voltage acquisition chip acquires the current and voltage of each path of PWM power supply signal and sends the current and voltage to the main control MCU through an I2C bus.

2. The adjustable current PWM power supply according to claim 1, wherein said adjustable power supply comprises a switching chip U1, a fuse F1, an inductor L1, a voltage dependent resistor V1, a capacitor C2, a transformer L2, a capacitor C1, a capacitor C4, a capacitor C3, a capacitor CM1 and a diode D1, the L line of 220V commercial power is connected with said fuse F1, the other end of said fuse F1 is respectively connected with said inductor L1, said voltage dependent resistor V1 and said capacitor C2, the other end of said inductor L1 is connected with the 3 rd winding of said transformer L2, the 2 nd winding of said transformer L2 is respectively connected with the other end of said voltage dependent resistor V1 and the other end of said capacitor C2, the 1 st winding of said transformer L2 is respectively connected with said capacitor C4 and the N pin of said switching chip U1, the 4 th winding of said transformer L2 is respectively connected with said capacitor C1 and the L pin of said switching chip U1, the other end of the capacitor C1 is connected with the other end of the capacitor C4, the capacitor C3, the capacitor CM1 and the diode D1 are connected in parallel between a VO + pin and a VO-pin of a conversion chip U1 respectively, and 15V voltage is output.

3. The adjustable current PWM power supply according to claim 2, further comprising a switching chip U2, wherein the 1 st pin of the switching chip U2 is connected to the 15V power output by the switching chip U1, the 2 nd pin of the switching chip U2 is connected to a resistor R2 and then connected to the 15V power output by the switching chip U1, the 15V power output by the switching chip U1 is further connected to a resistor R1, the other end of the resistor R1 is connected to a resistor R5 and the 3 rd pin of the switching chip U2, the resistor R5 is connected in parallel with a capacitor C7 and a capacitor C8, respectively, the 4 th pin and the 8 th pin of the switching chip U2 are grounded, the 5 th pin is connected to a capacitor C9, the other end of the capacitor C9 is grounded, the 6 th pin is connected to a capacitor C6, a resistor R3 and a resistor R6, the other end of the capacitor C6 is connected to the 3.3V power, and the other end of the resistor R6 is grounded, the other end of the resistor R3 is connected with a capacitor C10 and a capacitor C11 respectively, the other end of the capacitor C10 is grounded, the other end of the capacitor C11 is grounded, and the 7 th pin of the conversion chip U2 is connected with a 3.3V power supply.

4. The adjustable current PWM power supply according to claim 3, wherein the 3.3V power supply is respectively connected to a 32 th pin, a 48 th pin, a 64 th pin, a 19 th pin of the master MCU and an inductor L5, the other end of the inductor L5 is respectively connected to a 13 th pin of the master MCU and a capacitor C27, and the other end of the capacitor C27 is grounded;

the 41 th pin of the main control MCU is connected with a TIM1_ CH1 signal line, the 23 th pin is connected with a TIM1_ CH1N signal line, and a TIM1_ CH1 signal line and a TIM1_ CH1N signal line form a 1-path PWM signal PWM _ OUT 1;

the 16 th pin of the main control MCU is connected with a TIM2_ CH3 signal line, the 17 th pin is connected with a TIM2_ CH4 signal line, and a TIM1_ CH1 signal line and a TIM1_ CH1N signal line form a 1-path PWM signal PWM _ OUT 2;

the 26 th pin of the main control MCU is connected with a TIM3_ CH3 signal line, the 27 th pin is connected with a TIM3_ CH4 signal line, and a TIM3_ CH3 signal line and a TIM3_ CH4 signal line form a 1-path PWM signal PWM _ OUT 3;

the pin 61 of the main control MCU is connected with a TIM4_ CH3 signal line, the pin 62 is connected with a TIM4_ CH4 signal line, and a TIM4_ CH3 signal line and a TIM4_ CH4 signal line form a 1-path PWM signal PWM _ OUT 4.

5. The adjustable current PWM power supply of claim 4, wherein the 4-way PWM power supply signal comprises a PWM1_ OUT signal line, a PWM2_ OUT signal line, a PWM3_ OUT signal line, and a PWM4_ OUT signal line.

6. The adjustable current PWM power supply according to claim 5, wherein the driving circuits comprise a first driving circuit, a second driving circuit, a third driving circuit and a fourth driving circuit, and the first driving circuit, the second driving circuit, the third driving circuit and the fourth driving circuit have the same structure; the inputs of the first driving circuit are the TIM1_ CH1 signal line and the TIM1_ CHIN signal line, the TIM1_ CH1 signal line is connected to the resistor R45, the TIM1_ CHIN signal line is connected to the resistor R47, the resistor R45 is connected to the pin 1 of the driving chip U19, the resistor R47 is connected to the pin 2 of the driving chip U19, the pin 3 of the driving chip U19 is connected to ground, the pin 5 is connected to the +15V power supply, the resistor R19 and the capacitor C19 respectively, the capacitor C19 is connected to ground, the resistor R19 is connected to the anode of the diode D19, the cathode of the diode D19 is connected to the pin 8 of the driving chip U19, the pin 8 of the driving chip U19 is further connected to the capacitor C19, the other end of the capacitor C19 is connected to the pin 6 of the driving chip U19, the pin 6 of the driving chip 19 is further connected to the pin 6 of the driving chip 19, the PWM chip U19, the pin 6 _ CHIN is connected to the pin 19, the signal line is connected to the PWM chip OUT 19, the pin 19, the resistor R19 is connected to the pin 19 and the pin 19, the driving chip R19, the other end of the diode and the other end of the resistor R41 are respectively connected with a capacitor C56 and the grid of a MOS tube Q4, the drain of the MOS tube Q4 is connected with a power supply VCC, and the source of the MOS tube Q4 and the other pole of the capacitor C56 are respectively connected with a PWM1_ OUT signal line; the 4 th pin of the driving chip U19 is respectively connected with a diode D8 and a resistor R49, the other end of the diode D8 and the other end of the resistor R49 are respectively connected with a grid of a capacitor C60, a resistor R51 and a MOS transistor Q3, the other end of the capacitor C60, the other end of the resistor R51 and the source of the MOS transistor Q3 are respectively grounded, and the drain of the MOS transistor Q3 is connected with a PWM1_ OUT signal line.

7. The current-adjustable PWM power supply according to claim 6, wherein the current and voltage acquisition chip comprises a chip U11 and a chip U13, the PWM _ OUT1 signal line is connected with a fuse F2 and then is respectively connected with a 4 th pin of the chip U11 and a resistor R21, the other end of the resistor R21 is respectively connected with a PWM1_ OUT signal line and a 3 rd pin of the chip U11, the PWM1_ OUT signal line is further connected with a resistor R23, the other end of the resistor R23 is respectively connected with a resistor R29 and a 1 st pin of the chip U13, and the other end of the resistor R29 is grounded; the 6 th pin of the chip U11 is respectively connected with a 3.3V power supply and a capacitor C42, and the other end of the capacitor C42 and the 2 nd pin of the chip U11 are grounded; the 1 st pin of the chip U11 is connected to the resistor R27, the other end of the resistor R27 is connected to the capacitor C44 and the 4 th pin of the chip U13, the 2 nd pin, the 3 rd pin, the 5 th pin, the 9 th pin and the 10 th pin of the chip U13 are grounded, the 7 th pin is connected to the resistor R24 and the I2C1_ SDA signal line, the other end of the resistor R24 is connected to the resistor R25, the other end of the resistor R25 is connected to the I2C1_ SCL signal line, the 8 th pin of the chip U13 is connected to the I2C1_ SCL signal line, the 6 th pin is connected to the capacitor C46 and the capacitor CM6, the I2C1_ SDA signal line is connected to the 59 th pin of the main control MCU, and the I2C1_ SCL signal line is connected to the 58 th pin of the main control MCU.

8. The adjustable current PWM power supply according to claim 7, wherein the main control MCU chip is STM32F103RBT6, and pin 50 of the chip is connected to the upper computer.

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