4 Star 12 Fork 6


Create your Gitee Account
Explore and code with more than 12 million developers,Free private repositories !:)
Sign up
Clone or Download
Sync branch
Notice: Creating folder will generate an empty file .keep, because not support in Git

Synchronous Rectification Buck-Boost Digital Power Supply Based on STM32

A four-switch Buck-Boost digital power supply based on STM32G474, supporting TypeC interface PD decoy input and DC5.5 interface input, with input/output voltage up to 48V10A. This is my graduation project, now open-sourced, including schematic, PCB, program source code, case 3D model, etc.


Demo video:https://www.bilibili.com/video/BV1Ui421y7ip/

Based on CH32V307 smart electronic load open source, embedded competition work open source:https://blog.zeruns.tech/archives/785.html



The download address of the materials is at the end of the article.


This article designs a synchronous rectification Buck-Boost digital power supply based on STM32, the power circuit of which consists of MOSFET driving circuit, 4 switch Buck-Boost circuit, signal conditioning circuit, PD fast charging protocol circuit, auxiliary power circuit, MCU control circuit, etc.

The power supply can be powered through DC interface or Type-C interface, and the Type-C interface supports communication with the charger through PD fast charging protocol, automatically requesting and obtaining the maximum 20V working voltage. The power supply uses STM32G474 MCU to monitor the input and output voltage and current in real time, and adjusts the output PWM duty cycle through PID control algorithm, as well as realizes overvoltage and overcurrent protection. It can also sample the motherboard temperature to achieve overtemperature protection. In addition, it can display the power parameters in real time through the OLED screen, and set the output voltage and current through the rotary encoder and button, or communicate with the host computer through another Type-C interface to view the power parameters and waveforms in real time.

Design Performance Parameters

​ 电源设计性能参数如下表:

Item Specification
Input Voltage Range 12Vdc~48Vdc
Input Current Range 0~10A
Maximum Output Power 450W
Output Voltage Range 0.5Vdc~48Vdc
Output Current Range 0~10A
Output Voltage Ripple 峰峰值≤200mV
Switching Frequency 181.333kHz

Physical image

Using VOFA+ as the host computer software, you can monitor real-time power supply parameters (input voltage and current, output voltage and current, motherboard temperature, MCU temperature, power conversion efficiency, etc.) and waveform changes as shown below.

System Framework Diagram

Hardware Circuit Design

Component Selection Calculation

Inductor Calculation

​In a synchronous Buck-Boost power supply, the calculation of inductance needs to consider the working conditions under both Buck and Boost modes to ensure that the circuit can meet the requirements in both modes. Typically, the selection of inductance is based on the mode that requires the higher inductance.

​When the power supply operates in Buck mode (voltage reduction), assuming the maximum input voltage is 48V and the minimum output voltage is 5V, the minimum PWM duty cycle is calculated:

$$ D_{min} = \frac{V_{out_min}}{V_{in_max}} = \frac{5V}{48V} = 10.417% $$

​Define the inductance current ripple (25% of the maximum rated current ripple, with the maximum rated current set as 10A):

$$ \Delta I_L = 25% \cdot I_{out_nom} = 25% \times 10A = 2.5A $$

​Calculate the minimum required BUCK inductor:

$$ L_{minBuck} = \frac{V_{out_min}}{\Delta I_L \cdot f_{switch}} = \frac{5V}{2.5A \times 181333Hz} \times (1 - 10.417%) \approx 9.88\mu H $$

​When the power supply operates in BOOST mode (voltage boosting), with the rated input voltage of 24V as the calculation point, calculate the PWM duty cycle:

$$ D_{Bo} = 1 - \frac{V_{in_nom}}{V_{out_max}} = 1 - \frac{24V}{48V} = 50% $$

​In Boost mode, when taking 1A ($I_{minb}$), Boost enters continuous conduction mode (CCM), calculate inductance:

$$ L_{minBoost} = \frac{V_{out_max} \cdot D_{Bo}(1-D_{Bo})^2}{2 \cdot I_{minb} \cdot f_{switch}}
= \frac{48V \times 50% \times (1 - 50%)^2}{2 \times 1A \times 181333Hz} = 16.544\mu H $$

​Based on the calculated results derived from the formula, the minimum inductance value required to meet the predetermined ripple current requirement is determined. To ensure that this condition is met, an inductor with a value slightly higher than the calculated value should be selected. At the same time, it is essential to ensure that the saturation current of the selected inductor can withstand the highest peak current in the circuit. Since the efficiency factor was not considered in the calculation process, the actual duty cycle and peak current may be lower than the theoretical calculated values. Therefore, when making a selection, a certain safety margin should be taken into account to adapt to various conditions that may arise under actual working conditions.

​Taking into account the above factors, this design chooses a 1770 surface-mount package inductor with a saturation current of more than 10A and an inductance of 22μH as the inductor component for the BUCK-BOOST circuit.

Capacitance Calculation

To achieve a better output voltage ripple, the designed voltage ripple is taken as 50mV.

$$ \Delta V_{out} = 0.05V $$

Given the previously selected inductor of 22μH, the calculation here will also use this inductance value:

$$ L_{BB}=22\mu H $$

Calculate the minimum capacitance required for operation in BUCK step-down mode and BOOST step-up mode, respectively, as $C_{minBuck}$ and $C_{minBoost}$:

$$ C_{minBuck}=\frac{V_{out_min}\cdot(1-\frac{V_{out_min}}{V_{in_max}})}{8\cdot L_{BB}\cdot \Delta V_{out}\cdot {f_{switch}}^2}=15.48\mu F $$

$$ C_{minBoost}=\frac{I_{out_nom}\cdot(1-\frac{Vin_min}{Vout_max})}{\Delta Vout\cdot fswitch}=413.6\mu F $$

The design requires a certain margin, as well as lower output ripple, so a low ESR 220μF solid-state capacitor is selected in conjunction with a 470μF conventional electrolytic capacitor, totaling 690μF.

MOS Selection Calculation

Within the rated input and output voltage range, calculate the effective value of the input MOS current as:

$$ i_{mos_rms}=7.098A $$

In the MOSFET selection, the rated current $I_D$ of the MOS tube must be at least twice the maximum current that flows through the MOS tube (to prevent damage from excessive current during fault or short circuit conditions).

$$ 2×i_{mos_rms}=14.196A $$

In the selection of MOSFET, the rated voltage $V_{DS}$ should be greater than 1.5 times the maximum input voltage (to prevent spike breakdown).

$$ 1.5×Vin_max=72V $$

After referring to the previous calculations, for conventional application scenarios, a MOSFET with a rated current exceeding 15 amperes (A) and a voltage rating of 100 volts (V) can be selected. The selection for the lower MOSFET should be the same as for the upper MOSFET. Considering the heat dissipation situation, to minimize energy loss during conduction and switching processes, MOSFETs with low on-resistance ($R_{DS(on)}$) and low output capacitance ($C_{oss}$) should be given priority.

The MOSFET model selected for this design is the CJAC80SN10, produced by Jiangsu Changjing Technology Co., Ltd., which is a domestically produced MOSFET. It has a drain-source voltage rating ($V_{DS}$) of 100V and a maximum drain-source current ($I_D$) of 80A. Its on-resistance ($R_{DS(on)}$) is as low as 6.2mΩ, which is beneficial for reducing power loss when the device is in the on-state. Additionally, the output capacitance ($C_{oss}$) of this device has a typical value of 420pF, which is advantageous for reducing dynamic losses during switching transitions. Therefore, the CJAC80SN10 not only meets the electrical characteristics required by the project but also effectively reduces energy loss and improves the overall efficiency of the system.

Power Supply Board Circuit Design

Main Power Circuit

The following diagram represents the main power circuit of the synchronous BUCK-BOOST power supply. The input is on the left side; the synchronous BUCK step-down circuit consists of MOSFETs Q2 and Q4 and inductor L1. The synchronous BOOST step-up circuit is made up of MOSFETs Q3 and Q5 and inductor L1. Each MOSFET has a 10kΩ resistor in parallel between the gate and source terminals to ensure that the gate is not floating and to prevent unintended conduction.

The main power circuit has a symmetrical structure on the left and right sides. Both the input and output ends are equipped with one 470μF/63V aluminum electrolytic capacitor and one 220μF/63V solid-state aluminum electrolytic capacitor. In addition, there are two small surface-mount MLCCs (Multilayer Ceramic Capacitors) with parameters of 10μF/50V to filter high-frequency noise interference at the ports. R9 and R10 serve as dummy loads for the input and output ports, allowing for the rapid dissipation of residual energy in the circuit when the power is disconnected. R13 and R14 are high-precision 5mΩ resistors used for current sampling, with a subsequent differential amplification circuit to amplify the input and output current signals. CNT1 and CNT2 are the output terminals. L1 and L2 are surface-mount 1770 package and through-hole magnetic core inductor packages, respectively; only one should be soldered, and both are drawn to facilitate testing the effects and performance of different inductors.

Power Supply Input and Fast Charging Protocol Circuit

The following diagram represents the power supply's input interface and PD fast charging protocol communication circuit.

The power supply input features two types of interfaces: a DC5.5*2.5mm female connector and a Type-C female connector. The Type-C interface supports various fast charging protocols such as BC1.2, PD3.0/2.0, etc. The fast charging protocol chip used is the CH224K, which can communicate with fast charging chargers to output a voltage as high as 20V and supports up to 100W of power.

Diodes D1, D3, and D4 serve to prevent voltage backflow from the DC interface to the Type-C interface; the design does not allow both interfaces to be connected simultaneously. Diode D5 is used for reverse polarity protection. FH1 is the power input fuse holder, which accommodates a 12A fuse.

Driver Circuit

In the design of a synchronous BUCK-BOOST power supply, both the BUCK and BOOST circuits include high-side N-MOSFETs. Traditionally, the driving of these high-side N-MOSFETs is accomplished using transformer-isolated drivers, but this method increases the complexity of the circuit and enlarges the size of the circuit board.

This design selects two MOSFET driver chips with built-in bootstrap circuit functions, EG3112, to drive the MOSFETs of the BUCK and BOOST circuits. The EG3112 is a non-isolated complementary dual-channel driver chip; its 2A output driving current capability ensures that the MOSFET can turn on quickly; the chip also has a built-in dead-time control function to prevent shoot-through of the output driving signals, thereby enhancing the stability of the system. The specific circuit is shown in the figure below.

Taking the driving of the MOSFET in the BOOST step-up circuit as an example, PWM2L and PWM2H are PWM signals output from the STM32G474 microcontroller, which are sent to the LIN and HIN pins of the EG3112 driver chip. LO is the lower MOSFET driving signal output, and the driving resistor has a value of 10Ω. HO is the upper MOSFET driving signal output, and the driving resistor also has a value of 10Ω. D7 is the bootstrap diode for the upper MOSFET driving circuit, while diodes D9 and D11 are used to quickly discharge the gate charge, speeding up the turn-off speed of the MOSFET. C14 is the bootstrap capacitor.

The role of the driving resistor is to reduce oscillations that may occur on the PCB traces, distributed capacitance, inductors, and other components during the MOSFET switching process. By using a series resistor, these oscillations can be mitigated, improving the stability and reliability of the system.

Auxiliary Power Supply

The following diagram is the schematic of the power supply board's auxiliary power supply circuit.

The first-stage 12V output auxiliary power circuit uses the BUCK-type power chip TPS54360B, which integrates a high-side MOSFET, for its design. According to the chip's datasheet, a pull-down resistor on the RT pin can set the switching frequency; a 110kΩ resistor is selected here, corresponding to a switching frequency of 876.5kHz. A higher switching frequency allows for the use of a smaller inductor to save space. Based on this frequency, the inductance value should be greater than 9.75μH, so a 10μH inductor is selected, and SS310 is chosen as the freewheeling diode. C26 and C27 are input filter capacitors; feedback divider resistors R19 and R25 create a 0.8V reference voltage for the chip's FB pin to ensure the output voltage is maintained at 12V. C18 and C19 are the filter capacitors for the first-stage 12V output auxiliary power supply. The first-stage 12V output is mainly used to supply the input of the second-stage 6V step-down circuit, as well as the MOSFET driver circuit and cooling fan.

The second-stage 6V output auxiliary power circuit uses the synchronous rectification BUCK-type power chip SY8205, which integrates a MOSFET, for its design. According to the datasheet, the chip's switching frequency is fixed at 500kHz, and a 10μH inductor is selected for the auxiliary power BUCK circuit. C21 and C22 are input filter capacitors; feedback divider resistors R23 and R26 create a 0.6V reference voltage for the chip's FB pin to ensure the output voltage is maintained at 6V. C24 and C25 are the filter capacitors for the second-stage 6V output auxiliary power supply. Since directly using a linear regulator to step down from 12V to 5V would result in significant loss, a switch-mode power supply is first used to step down to a voltage close to 5V, and then a linear regulator is used to step down to the target voltage. This approach ensures higher efficiency and lower output ripple.

The second-stage output of 6V is stepped down to 5V by the linear voltage regulator chip AMS1117-5 to serve as the third-level auxiliary power supply. The voltage reference chip REF3033 is used for signal conditioning, OLED display, USB communication, and other functional circuits.

5V DC is stepped down to 3.3V by the linear voltage regulator chip AMS1117-3.3 to serve as the fourth-level auxiliary power supply, used for MCU, buzzer, Flash chip, and other circuits.

The voltage reference chip REF3033 outputs a 3.3V reference voltage for the MCU's VREF pin, serving as the reference voltage for the MCU's built-in ADC to improve the accuracy of ADC sampling.

Signal Conditioning Circuit

As shown in the diagram above, the input and output voltage sampling and signal conditioning circuit of this design utilizes differential amplification technology. The differential amplification topology can effectively reduce the interference of high-frequency noise in the switching power supply on the signal conditioning circuit, enhancing the stability and reliability of the signal. In this circuit, the low-offset operational amplifier GS8558-SR is selected to improve the precision of the conversion. The GS8558-SR op-amp has excellent DC accuracy and low bias current characteristics, which are crucial for improving the performance of the entire signal conditioning circuit.

Differential amplification circuit feedback resistor:

$$ R_{38}=4.7kΩ $$

$$ R_{36}=75kΩ $$

Calculate the differential amplification gain:

$$ K_V=\frac{R_{38}}{R_{36}}=0.062667 $$

The MCU's ADC has a maximum sampling voltage of 3.3V, which is the reference voltage output by the voltage reference chip, so the maximum input and output voltage values that can be sampled can be calculated as follows:

$$ V_{max}=\frac{3.3V}{K_V}=52.66V $$

To better suppress the interference of high-frequency noise from the switching power supply on the differential amplification circuit, decoupling capacitors C40 and C41 are added to the power supply pins of the operational amplifier for filtering. Capacitors are selected as MLCCs (Multilayer Ceramic Capacitors), which have a lower ESR (Equivalent Series Resistance) and ESL (Equivalent Series Inductance), thus providing better filtering effects for high-frequency noise. Additionally, an RC low-pass filter circuit is formed by adding resistor R35 and capacitor C39 at the output end to filter out high-frequency noise.

As shown in the diagram above, the input and output current conditioning circuits use a differential amplification method, and the output current sampling resistor is:

$$ R_{14}=5mΩ $$

The feedback resistors in the differential amplification circuit are:

$$ R_{48}=6.2kΩ $$

$$ R_{46}=100Ω $$

Calculate the differential amplification gain:

$$ K_I=\frac{R_{48}}{R_{46}}=62 $$

That is to say, for every 1A of current output, there is a voltage of 310mV.

Given that the MCU's ADC has a maximum sampling voltage of 3.3V, provided by the voltage reference chip, you can calculate the maximum input and output current values that can be sampled as follows:

$$ I_{max}=\frac{3.3V}{K_I \times R_{14}}=10.65A $$

MCU Control Circuit

The digital power supply design in this project uses the STM32G474RET6 chip as the controller, which has the notable features of a simple peripheral circuit, diverse control methods, and excellent expansion capabilities. To achieve an accurate clock signal, the controller uses an external crystal oscillator X1, which is a quartz crystal oscillator with a frequency of 25 megahertz (MHz). In addition, the circuit also includes multiple filtering capacitors, including C45, C51, C56, C46, and C52, which are used for different digital power supply pins of the microcontroller (MCU) to ensure power stability and reduce noise interference. Resistor R49 and capacitor C49 form a power-on reset circuit, and SW1 is the MCU reset button. U11 is a USB-to-serial chip, model CH340C, connected to the second Type-C interface, with the serial port connected to the MCU's USART1 interface. U10 is a Flash memory chip, model W25Q64, used to store parameter settings and other information, connected to the MCU's SPI3 interface. Q6 is the driving MOSFET for the buzzer, used to control the buzzer, with the MOSFET gate connected to the MCU's PB5 port. Terminal H1 is the SWD programming port. H2 and H4 are PH2.0 connectors, used to connect with the control panel, with connectors reserved for the USART2 interface, which can conveniently replace the control panel with a serial screen, and can also add an ESP32 to increase networking and wireless control functions. D13 is a 5V reverse polarity protection diode.

Cooling Fan Drive and Motherboard Temperature Sampling Circuit

The schematic diagram of the motherboard temperature sampling circuit and the cooling fan drive circuit is shown below. The principle of the power supply motherboard temperature sampling is to use an NTC thermistor R2 in series with a pull-down resistor R4 to output a voltage divider to the MCU's ADC port for sampling. The NTC thermistor used has a resistance value of 10kΩ and a B value of 3950K.

The cooling fan is driven using an N-MOSFET, model AO3400. A diode D2 is reverse-biased in parallel on the fan interface to prevent damage caused by the back electromotive force (back EMF) generated by the motor. When the motor is powered off, due to rotational inertia, the rotor of the motor will not stop immediately but will continue to rotate and generate a voltage. This voltage can potentially damage the transistors or integrated circuits in the circuit, especially when the motor is connected to these components through a semiconductor switch, such as an MOSFET.

Control Panel Circuit Design

The schematic diagram of the control panel circuit is shown below. SW1 is a rotary encoder used for setting parameters and the like, while SW2 and SW3 are buttons; SW2 is used to switch settings, and SW3 is used to control the power output's on and off. LED1 is the system operation status indicator light, which blinks at intervals of 500ms during normal operation. LED2 is the output status indicator light, which lights up when the output is on and turns off when the output is off. OLED1 is the OLED screen, used to display power supply parameters and status information, etc.

User Manual

You can adjust the output voltage and current values using the buttons and rotary encoder. As shown in the figure below, the inverse color display indicates the current setting digit. By rotating the encoder, you can increase or decrease the value. Pressing the encoder button allows you to switch to the next digit for setting. The SW2 button is used to switch between different settings. The set data will be automatically saved to the Flash memory chip, and the data will be read from the chip during the next power-up.

The SW3 button is used to turn the power output on or off.

You can switch to the data display page to view the current input and output voltage and current of the power supply, as well as information such as motherboard temperature and MCU temperature, as shown in the figure below.

You can switch to the settings page to configure the threshold values for over-temperature, over-current, and over-voltage protection, as shown in the figure below. The data set will be automatically saved to the Flash memory chip, and the data will be retrieved from the chip during the next startup.

Ripple Test

Use an electronic load and oscilloscope to test the power supply output performance and output ripple, as shown in the figure below. At an input of 36V and an output of 12V at 2A, the peak-to-peak ripple measured is approximately 42mV, as illustrated in the figure below.

Efficiency Test

The power supply conversion efficiency when inputting 20V and outputting 12V at 10A is measured to be 92%, as shown in the figure below.

MOSFET Gate Waveform

The following table shows the conversion efficiency at various input and output voltages, with the highest efficiency reaching 94.3%.

Input Voltage (V) Input Current (A) Input Power (W) Output Voltage (V) Output Current (A) Output Power (W) Efficiency (%)
20.003 4.035 80.712 15.010 5.000 75.050 92.985
47.999 5.335 256.075 24.040 9.900 237.996 92.940
48.000 7.875 378.000 36.020 9.900 356.598 94.338
48.000 9.860 473.280 45.030 9.900 445.797 94.193
23.998 8.835 212.022 48.070 4.000 192.280 90.689
23.998 9.830 235.900 35.998 6.001 216.024 91.574
12.099 9.166 110.899 24.070 4.000 96.280 86.817
20.008 2.645 52.921 4.970 9.000 44.730 84.522
20.008 10.550 211.084 24.030 8.000 192.240 91.073
36.000 6.418 231.048 24.010 9.000 216.090 93.526
36.000 10.540 379.440 35.950 9.800 352.310 92.850

Efficiency Test

The power supply conversion efficiency when inputting 20V and outputting 24V is tested on the gate waveforms of each MOSFET.

BUCK circuit upper and lower tube to ground voltage waveform diagram:

BOOST Circuit Upper and Lower Tube to Ground Voltage Waveform Diagram:





Download Links for Materials

The following links include materials such as: EasyEDA project files, schematic diagram PDFs, datasheets for each chip, source code project compressed package, and some reference program codes.






Known Issues

  1. The SY8205 chip in the auxiliary power supply enters PFM (Pulse Frequency Modulation) mode at low load, resulting in a lower frequency and thus generating slight noise.
  2. The PID control program for constant current mode is not well written; it only remains stable under pure resistive loads. (Constant voltage mode is not problematic.)

Other Recommended Open Source Projects


GNU GENERAL PUBLIC LICENSE Version 3, 29 June 2007 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/> Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. Preamble The GNU General Public License is a free, copyleft license for software and other kinds of works. The licenses for most software and other practical works are designed to take away your freedom to share and change the works. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change all versions of a program--to make sure it remains free software for all its users. We, the Free Software Foundation, use the GNU General Public License for most of our software; it applies also to any other work released this way by its authors. You can apply it to your programs, too. When we speak of free software, we are referring to freedom, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for them if you wish), that you receive source code or can get it if you want it, that you can change the software or use pieces of it in new free programs, and that you know you can do these things. To protect your rights, we need to prevent others from denying you these rights or asking you to surrender the rights. Therefore, you have certain responsibilities if you distribute copies of the software, or if you modify it: responsibilities to respect the freedom of others. For example, if you distribute copies of such a program, whether gratis or for a fee, you must pass on to the recipients the same freedoms that you received. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights. Developers that use the GNU GPL protect your rights with two steps: (1) assert copyright on the software, and (2) offer you this License giving you legal permission to copy, distribute and/or modify it. For the developers' and authors' protection, the GPL clearly explains that there is no warranty for this free software. For both users' and authors' sake, the GPL requires that modified versions be marked as changed, so that their problems will not be attributed erroneously to authors of previous versions. Some devices are designed to deny users access to install or run modified versions of the software inside them, although the manufacturer can do so. This is fundamentally incompatible with the aim of protecting users' freedom to change the software. The systematic pattern of such abuse occurs in the area of products for individuals to use, which is precisely where it is most unacceptable. Therefore, we have designed this version of the GPL to prohibit the practice for those products. If such problems arise substantially in other domains, we stand ready to extend this provision to those domains in future versions of the GPL, as needed to protect the freedom of users. Finally, every program is threatened constantly by software patents. States should not allow patents to restrict development and use of software on general-purpose computers, but in those that do, we wish to avoid the special danger that patents applied to a free program could make it effectively proprietary. To prevent this, the GPL assures that patents cannot be used to render the program non-free. The precise terms and conditions for copying, distribution and modification follow. TERMS AND CONDITIONS 0. Definitions. "This License" refers to version 3 of the GNU General Public License. "Copyright" also means copyright-like laws that apply to other kinds of works, such as semiconductor masks. "The Program" refers to any copyrightable work licensed under this License. Each licensee is addressed as "you". "Licensees" and "recipients" may be individuals or organizations. To "modify" a work means to copy from or adapt all or part of the work in a fashion requiring copyright permission, other than the making of an exact copy. The resulting work is called a "modified version" of the earlier work or a work "based on" the earlier work. A "covered work" means either the unmodified Program or a work based on the Program. To "propagate" a work means to do anything with it that, without permission, would make you directly or secondarily liable for infringement under applicable copyright law, except executing it on a computer or modifying a private copy. Propagation includes copying, distribution (with or without modification), making available to the public, and in some countries other activities as well. To "convey" a work means any kind of propagation that enables other parties to make or receive copies. Mere interaction with a user through a computer network, with no transfer of a copy, is not conveying. An interactive user interface displays "Appropriate Legal Notices" to the extent that it includes a convenient and prominently visible feature that (1) displays an appropriate copyright notice, and (2) tells the user that there is no warranty for the work (except to the extent that warranties are provided), that licensees may convey the work under this License, and how to view a copy of this License. If the interface presents a list of user commands or options, such as a menu, a prominent item in the list meets this criterion. 1. Source Code. The "source code" for a work means the preferred form of the work for making modifications to it. "Object code" means any non-source form of a work. A "Standard Interface" means an interface that either is an official standard defined by a recognized standards body, or, in the case of interfaces specified for a particular programming language, one that is widely used among developers working in that language. The "System Libraries" of an executable work include anything, other than the work as a whole, that (a) is included in the normal form of packaging a Major Component, but which is not part of that Major Component, and (b) serves only to enable use of the work with that Major Component, or to implement a Standard Interface for which an implementation is available to the public in source code form. A "Major Component", in this context, means a major essential component (kernel, window system, and so on) of the specific operating system (if any) on which the executable work runs, or a compiler used to produce the work, or an object code interpreter used to run it. The "Corresponding Source" for a work in object code form means all the source code needed to generate, install, and (for an executable work) run the object code and to modify the work, including scripts to control those activities. However, it does not include the work's System Libraries, or general-purpose tools or generally available free programs which are used unmodified in performing those activities but which are not part of the work. For example, Corresponding Source includes interface definition files associated with source files for the work, and the source code for shared libraries and dynamically linked subprograms that the work is specifically designed to require, such as by intimate data communication or control flow between those subprograms and other parts of the work. The Corresponding Source need not include anything that users can regenerate automatically from other parts of the Corresponding Source. The Corresponding Source for a work in source code form is that same work. 2. Basic Permissions. All rights granted under this License are granted for the term of copyright on the Program, and are irrevocable provided the stated conditions are met. This License explicitly affirms your unlimited permission to run the unmodified Program. The output from running a covered work is covered by this License only if the output, given its content, constitutes a covered work. This License acknowledges your rights of fair use or other equivalent, as provided by copyright law. You may make, run and propagate covered works that you do not convey, without conditions so long as your license otherwise remains in force. You may convey covered works to others for the sole purpose of having them make modifications exclusively for you, or provide you with facilities for running those works, provided that you comply with the terms of this License in conveying all material for which you do not control copyright. Those thus making or running the covered works for you must do so exclusively on your behalf, under your direction and control, on terms that prohibit them from making any copies of your copyrighted material outside their relationship with you. Conveying under any other circumstances is permitted solely under the conditions stated below. Sublicensing is not allowed; section 10 makes it unnecessary. 3. Protecting Users' Legal Rights From Anti-Circumvention Law. No covered work shall be deemed part of an effective technological measure under any applicable law fulfilling obligations under article 11 of the WIPO copyright treaty adopted on 20 December 1996, or similar laws prohibiting or restricting circumvention of such measures. When you convey a covered work, you waive any legal power to forbid circumvention of technological measures to the extent such circumvention is effected by exercising rights under this License with respect to the covered work, and you disclaim any intention to limit operation or modification of the work as a means of enforcing, against the work's users, your or third parties' legal rights to forbid circumvention of technological measures. 4. Conveying Verbatim Copies. You may convey verbatim copies of the Program's source code as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice; keep intact all notices stating that this License and any non-permissive terms added in accord with section 7 apply to the code; keep intact all notices of the absence of any warranty; and give all recipients a copy of this License along with the Program. You may charge any price or no price for each copy that you convey, and you may offer support or warranty protection for a fee. 5. Conveying Modified Source Versions. You may convey a work based on the Program, or the modifications to produce it from the Program, in the form of source code under the terms of section 4, provided that you also meet all of these conditions: a) The work must carry prominent notices stating that you modified it, and giving a relevant date. b) The work must carry prominent notices stating that it is released under this License and any conditions added under section 7. This requirement modifies the requirement in section 4 to "keep intact all notices". c) You must license the entire work, as a whole, under this License to anyone who comes into possession of a copy. This License will therefore apply, along with any applicable section 7 additional terms, to the whole of the work, and all its parts, regardless of how they are packaged. This License gives no permission to license the work in any other way, but it does not invalidate such permission if you have separately received it. d) If the work has interactive user interfaces, each must display Appropriate Legal Notices; however, if the Program has interactive interfaces that do not display Appropriate Legal Notices, your work need not make them do so. A compilation of a covered work with other separate and independent works, which are not by their nature extensions of the covered work, and which are not combined with it such as to form a larger program, in or on a volume of a storage or distribution medium, is called an "aggregate" if the compilation and its resulting copyright are not used to limit the access or legal rights of the compilation's users beyond what the individual works permit. Inclusion of a covered work in an aggregate does not cause this License to apply to the other parts of the aggregate. 6. Conveying Non-Source Forms. You may convey a covered work in object code form under the terms of sections 4 and 5, provided that you also convey the machine-readable Corresponding Source under the terms of this License, in one of these ways: a) Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by the Corresponding Source fixed on a durable physical medium customarily used for software interchange. b) Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by a written offer, valid for at least three years and valid for as long as you offer spare parts or customer support for that product model, to give anyone who possesses the object code either (1) a copy of the Corresponding Source for all the software in the product that is covered by this License, on a durable physical medium customarily used for software interchange, for a price no more than your reasonable cost of physically performing this conveying of source, or (2) access to copy the Corresponding Source from a network server at no charge. c) Convey individual copies of the object code with a copy of the written offer to provide the Corresponding Source. This alternative is allowed only occasionally and noncommercially, and only if you received the object code with such an offer, in accord with subsection 6b. d) Convey the object code by offering access from a designated place (gratis or for a charge), and offer equivalent access to the Corresponding Source in the same way through the same place at no further charge. You need not require recipients to copy the Corresponding Source along with the object code. If the place to copy the object code is a network server, the Corresponding Source may be on a different server (operated by you or a third party) that supports equivalent copying facilities, provided you maintain clear directions next to the object code saying where to find the Corresponding Source. Regardless of what server hosts the Corresponding Source, you remain obligated to ensure that it is available for as long as needed to satisfy these requirements. e) Convey the object code using peer-to-peer transmission, provided you inform other peers where the object code and Corresponding Source of the work are being offered to the general public at no charge under subsection 6d. A separable portion of the object code, whose source code is excluded from the Corresponding Source as a System Library, need not be included in conveying the object code work. A "User Product" is either (1) a "consumer product", which means any tangible personal property which is normally used for personal, family, or household purposes, or (2) anything designed or sold for incorporation into a dwelling. In determining whether a product is a consumer product, doubtful cases shall be resolved in favor of coverage. For a particular product received by a particular user, "normally used" refers to a typical or common use of that class of product, regardless of the status of the particular user or of the way in which the particular user actually uses, or expects or is expected to use, the product. A product is a consumer product regardless of whether the product has substantial commercial, industrial or non-consumer uses, unless such uses represent the only significant mode of use of the product. "Installation Information" for a User Product means any methods, procedures, authorization keys, or other information required to install and execute modified versions of a covered work in that User Product from a modified version of its Corresponding Source. The information must suffice to ensure that the continued functioning of the modified object code is in no case prevented or interfered with solely because modification has been made. If you convey an object code work under this section in, or with, or specifically for use in, a User Product, and the conveying occurs as part of a transaction in which the right of possession and use of the User Product is transferred to the recipient in perpetuity or for a fixed term (regardless of how the transaction is characterized), the Corresponding Source conveyed under this section must be accompanied by the Installation Information. But this requirement does not apply if neither you nor any third party retains the ability to install modified object code on the User Product (for example, the work has been installed in ROM). The requirement to provide Installation Information does not include a requirement to continue to provide support service, warranty, or updates for a work that has been modified or installed by the recipient, or for the User Product in which it has been modified or installed. Access to a network may be denied when the modification itself materially and adversely affects the operation of the network or violates the rules and protocols for communication across the network. Corresponding Source conveyed, and Installation Information provided, in accord with this section must be in a format that is publicly documented (and with an implementation available to the public in source code form), and must require no special password or key for unpacking, reading or copying. 7. Additional Terms. "Additional permissions" are terms that supplement the terms of this License by making exceptions from one or more of its conditions. Additional permissions that are applicable to the entire Program shall be treated as though they were included in this License, to the extent that they are valid under applicable law. If additional permissions apply only to part of the Program, that part may be used separately under those permissions, but the entire Program remains governed by this License without regard to the additional permissions. When you convey a copy of a covered work, you may at your option remove any additional permissions from that copy, or from any part of it. (Additional permissions may be written to require their own removal in certain cases when you modify the work.) You may place additional permissions on material, added by you to a covered work, for which you have or can give appropriate copyright permission. Notwithstanding any other provision of this License, for material you add to a covered work, you may (if authorized by the copyright holders of that material) supplement the terms of this License with terms: a) Disclaiming warranty or limiting liability differently from the terms of sections 15 and 16 of this License; or b) Requiring preservation of specified reasonable legal notices or author attributions in that material or in the Appropriate Legal Notices displayed by works containing it; or c) Prohibiting misrepresentation of the origin of that material, or requiring that modified versions of such material be marked in reasonable ways as different from the original version; or d) Limiting the use for publicity purposes of names of licensors or authors of the material; or e) Declining to grant rights under trademark law for use of some trade names, trademarks, or service marks; or f) Requiring indemnification of licensors and authors of that material by anyone who conveys the material (or modified versions of it) with contractual assumptions of liability to the recipient, for any liability that these contractual assumptions directly impose on those licensors and authors. All other non-permissive additional terms are considered "further restrictions" within the meaning of section 10. If the Program as you received it, or any part of it, contains a notice stating that it is governed by this License along with a term that is a further restriction, you may remove that term. If a license document contains a further restriction but permits relicensing or conveying under this License, you may add to a covered work material governed by the terms of that license document, provided that the further restriction does not survive such relicensing or conveying. If you add terms to a covered work in accord with this section, you must place, in the relevant source files, a statement of the additional terms that apply to those files, or a notice indicating where to find the applicable terms. Additional terms, permissive or non-permissive, may be stated in the form of a separately written license, or stated as exceptions; the above requirements apply either way. 8. Termination. You may not propagate or modify a covered work except as expressly provided under this License. Any attempt otherwise to propagate or modify it is void, and will automatically terminate your rights under this License (including any patent licenses granted under the third paragraph of section 11). However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation. Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice. Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, you do not qualify to receive new licenses for the same material under section 10. 9. Acceptance Not Required for Having Copies. You are not required to accept this License in order to receive or run a copy of the Program. Ancillary propagation of a covered work occurring solely as a consequence of using peer-to-peer transmission to receive a copy likewise does not require acceptance. However, nothing other than this License grants you permission to propagate or modify any covered work. These actions infringe copyright if you do not accept this License. Therefore, by modifying or propagating a covered work, you indicate your acceptance of this License to do so. 10. Automatic Licensing of Downstream Recipients. Each time you convey a covered work, the recipient automatically receives a license from the original licensors, to run, modify and propagate that work, subject to this License. You are not responsible for enforcing compliance by third parties with this License. An "entity transaction" is a transaction transferring control of an organization, or substantially all assets of one, or subdividing an organization, or merging organizations. If propagation of a covered work results from an entity transaction, each party to that transaction who receives a copy of the work also receives whatever licenses to the work the party's predecessor in interest had or could give under the previous paragraph, plus a right to possession of the Corresponding Source of the work from the predecessor in interest, if the predecessor has it or can get it with reasonable efforts. You may not impose any further restrictions on the exercise of the rights granted or affirmed under this License. For example, you may not impose a license fee, royalty, or other charge for exercise of rights granted under this License, and you may not initiate litigation (including a cross-claim or counterclaim in a lawsuit) alleging that any patent claim is infringed by making, using, selling, offering for sale, or importing the Program or any portion of it. 11. Patents. A "contributor" is a copyright holder who authorizes use under this License of the Program or a work on which the Program is based. The work thus licensed is called the contributor's "contributor version". A contributor's "essential patent claims" are all patent claims owned or controlled by the contributor, whether already acquired or hereafter acquired, that would be infringed by some manner, permitted by this License, of making, using, or selling its contributor version, but do not include claims that would be infringed only as a consequence of further modification of the contributor version. For purposes of this definition, "control" includes the right to grant patent sublicenses in a manner consistent with the requirements of this License. Each contributor grants you a non-exclusive, worldwide, royalty-free patent license under the contributor's essential patent claims, to make, use, sell, offer for sale, import and otherwise run, modify and propagate the contents of its contributor version. In the following three paragraphs, a "patent license" is any express agreement or commitment, however denominated, not to enforce a patent (such as an express permission to practice a patent or covenant not to sue for patent infringement). To "grant" such a patent license to a party means to make such an agreement or commitment not to enforce a patent against the party. If you convey a covered work, knowingly relying on a patent license, and the Corresponding Source of the work is not available for anyone to copy, free of charge and under the terms of this License, through a publicly available network server or other readily accessible means, then you must either (1) cause the Corresponding Source to be so available, or (2) arrange to deprive yourself of the benefit of the patent license for this particular work, or (3) arrange, in a manner consistent with the requirements of this License, to extend the patent license to downstream recipients. "Knowingly relying" means you have actual knowledge that, but for the patent license, your conveying the covered work in a country, or your recipient's use of the covered work in a country, would infringe one or more identifiable patents in that country that you have reason to believe are valid. If, pursuant to or in connection with a single transaction or arrangement, you convey, or propagate by procuring conveyance of, a covered work, and grant a patent license to some of the parties receiving the covered work authorizing them to use, propagate, modify or convey a specific copy of the covered work, then the patent license you grant is automatically extended to all recipients of the covered work and works based on it. A patent license is "discriminatory" if it does not include within the scope of its coverage, prohibits the exercise of, or is conditioned on the non-exercise of one or more of the rights that are specifically granted under this License. You may not convey a covered work if you are a party to an arrangement with a third party that is in the business of distributing software, under which you make payment to the third party based on the extent of your activity of conveying the work, and under which the third party grants, to any of the parties who would receive the covered work from you, a discriminatory patent license (a) in connection with copies of the covered work conveyed by you (or copies made from those copies), or (b) primarily for and in connection with specific products or compilations that contain the covered work, unless you entered into that arrangement, or that patent license was granted, prior to 28 March 2007. Nothing in this License shall be construed as excluding or limiting any implied license or other defenses to infringement that may otherwise be available to you under applicable patent law. 12. No Surrender of Others' Freedom. If conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot convey a covered work so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not convey it at all. For example, if you agree to terms that obligate you to collect a royalty for further conveying from those to whom you convey the Program, the only way you could satisfy both those terms and this License would be to refrain entirely from conveying the Program. 13. Use with the GNU Affero General Public License. Notwithstanding any other provision of this License, you have permission to link or combine any covered work with a work licensed under version 3 of the GNU Affero General Public License into a single combined work, and to convey the resulting work. The terms of this License will continue to apply to the part which is the covered work, but the special requirements of the GNU Affero General Public License, section 13, concerning interaction through a network will apply to the combination as such. 14. Revised Versions of this License. The Free Software Foundation may publish revised and/or new versions of the GNU General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. Each version is given a distinguishing version number. If the Program specifies that a certain numbered version of the GNU General Public License "or any later version" applies to it, you have the option of following the terms and conditions either of that numbered version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of the GNU General Public License, you may choose any version ever published by the Free Software Foundation. If the Program specifies that a proxy can decide which future versions of the GNU General Public License can be used, that proxy's public statement of acceptance of a version permanently authorizes you to choose that version for the Program. Later license versions may give you additional or different permissions. However, no additional obligations are imposed on any author or copyright holder as a result of your choosing to follow a later version. 15. Disclaimer of Warranty. THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 16. Limitation of Liability. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. 17. Interpretation of Sections 15 and 16. If the disclaimer of warranty and limitation of liability provided above cannot be given local legal effect according to their terms, reviewing courts shall apply local law that most closely approximates an absolute waiver of all civil liability in connection with the Program, unless a warranty or assumption of liability accompanies a copy of the Program in return for a fee. END OF TERMS AND CONDITIONS How to Apply These Terms to Your New Programs If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms. To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively state the exclusion of warranty; and each file should have at least the "copyright" line and a pointer to where the full notice is found. <one line to give the program's name and a brief idea of what it does.> Copyright (C) <year> <name of author> This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. Also add information on how to contact you by electronic and paper mail. If the program does terminal interaction, make it output a short notice like this when it starts in an interactive mode: <program> Copyright (C) <year> <name of author> This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. This is free software, and you are welcome to redistribute it under certain conditions; type `show c' for details. The hypothetical commands `show w' and `show c' should show the appropriate parts of the General Public License. Of course, your program's commands might be different; for a GUI interface, you would use an "about box". You should also get your employer (if you work as a programmer) or school, if any, to sign a "copyright disclaimer" for the program, if necessary. For more information on this, and how to apply and follow the GNU GPL, see <http://www.gnu.org/licenses/>. The GNU General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Lesser General Public License instead of this License. But first, please read <http://www.gnu.org/philosophy/why-not-lgpl.html>.


一款基于STM32G474的四开关Buck-Boost数字电源,支持TypeC接口PD诱骗输入和DC5.5接口输入,输入/输出最高48V10A,这是我的毕业设计,现在开源出来,含原理图、PCB、程序源码、外壳3D模型等资料。 expand collapse




Load More
can not load any more
马建仓 AI 助手


344bd9b3 5694891 D2dac590 5694891