CN115549229A - Short-circuit protection circuit and method, and related charging power supply and electronic equipment - Google Patents
Short-circuit protection circuit and method, and related charging power supply and electronic equipment Download PDFInfo
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- CN115549229A CN115549229A CN202111258799.0A CN202111258799A CN115549229A CN 115549229 A CN115549229 A CN 115549229A CN 202111258799 A CN202111258799 A CN 202111258799A CN 115549229 A CN115549229 A CN 115549229A
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/0029—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits
- H02J7/00308—Overvoltage protection
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/007—Regulation of charging or discharging current or voltage
- H02J7/00712—Regulation of charging or discharging current or voltage the cycle being controlled or terminated in response to electric parameters
- H02J7/00714—Regulation of charging or discharging current or voltage the cycle being controlled or terminated in response to electric parameters in response to battery charging or discharging current
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Abstract
The application discloses short-circuit protection circuit, method and relevant charging power supply and electronic equipment, the circuit includes the power, control chip, first resistance, second resistance and output port, but power double-circuit output current, establish mutual protection mechanism through series connection between two resistance (first resistance and second resistance), play the guard action to whole circuit, when the components and parts short circuit condition appears in the circuit, the output voltage of accessible regulation power makes it satisfy the requirement of LPS standard, to prevent that the too big component and parts that cause of output voltage of power from burning out, thereby arouse the condition such as conflagration, be favorable to guaranteeing the charging safety of power use scene.
Description
Technical Field
The present application relates to the field of electronic circuit technologies, and in particular, to a short-circuit protection circuit, a short-circuit protection method, a related charging power supply, and an electronic device.
Background
With the rapid development of electronic products, more and more power supply products with quick charging protocols are available in the market, and due to the protection of charging equipment such as mobile phones, the specification requirements of the protocols are more and more strict, and the meeting of the specification requirements is the basic requirements of the power supply products. Among other things, LPS (power limited power supply) requirements are specified in the IEC 60950 standard, and such requirements can be used to define a power supply with relatively low maximum voltage, current, and capacitance.
At present, in general, an output current detection resistor can be included in a power supply product circuit, and once the output current detection resistor is short-circuited, a traditional power supply does not make a targeted protection action, or the power supply does not meet the LPS authentication requirement, and a fire or an electric shock phenomenon may be triggered.
Disclosure of Invention
The embodiment of the application provides a short-circuit protection circuit, a short-circuit protection method, a related charging power supply and electronic equipment, and the output voltage of the power supply can be adjusted to meet the requirement of an LPS standard, so that the situation that components are burnt due to the fact that the output voltage of the power supply is too large is prevented, fire disasters and the like are caused, and the charging safety of power supply use scenes is guaranteed.
A first aspect of embodiments of the present application provides a short-circuit protection circuit,
the short-circuit protection includes: a power supply, a control chip, a first resistor, a second resistor and an output port, wherein,
one end of the power supply is connected with a first port of the control chip, the other end of the power supply is connected with an input end of the first resistor and a second port of the control chip, an output end of the first resistor is connected with a third port of the control chip and a first port of the output port, the second resistor is connected between the power supply and the output port, an input end of the second resistor is connected with a fourth port of the control chip, an output end of the second resistor is connected with a fifth port of the control chip, and a second port of the output port is grounded;
the control chip is used for detecting and obtaining a first voltage at two ends of the first resistor and a second voltage at two ends of the second resistor;
the control chip is further configured to determine a short-circuit condition of the first resistor and/or the second resistor according to the first voltage and the second voltage, and adjust the output voltage of the power supply when the first resistor and/or the second resistor is/are short-circuited.
A second aspect of the present application provides a charging power supply, including the short-circuit protection circuit disclosed in the first aspect of the embodiment of the present application.
The third aspect of the present application provides an electronic device including the charging power supply disclosed in the second aspect of the embodiment of the present application.
In an embodiment of the present application, the short-circuit protection circuit includes: the power supply comprises a power supply, a control chip, a first resistor, a second resistor and an output port, wherein one end of the power supply is connected with a first port of the control chip, the other end of the power supply is connected with an input end of the first resistor and a second port of the control chip, an output end of the first resistor is connected with a third port of the control chip and the first port of the output port, an input end of the second resistor is connected with a fourth port of the control chip and the second port of the output port, and an output end of the second resistor is connected with a fifth port of the control chip; the control chip is used for detecting and obtaining a first voltage at two ends of the first resistor and a second voltage at two ends of the second resistor; and the control chip is also used for determining the short circuit condition of the first resistor and/or the second resistor according to the first voltage and the second voltage, and regulating the output voltage of the power supply when the first resistor and/or the second resistor are short-circuited. So, but the power double-circuit output current establishes mutual protection mechanism through series connection between two resistance (first resistance and second resistance), plays the guard action to whole circuit, and when the components and parts short circuit condition appeared in the circuit, the output voltage of accessible regulation power made its satisfy the requirement of LPS standard to prevent that the output voltage of power is too big to cause the components and parts to burn out, thereby arouse the condition such as conflagration, be favorable to guaranteeing the charging safety of power service scene.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments or the background art of the present application, the drawings referred to in the embodiments or the background art of the present application will be briefly described below.
Fig. 1A is a schematic structural diagram of a short-circuit protection circuit according to an embodiment of the present disclosure;
fig. 1B is a schematic structural diagram of a short-circuit protection circuit according to an embodiment of the present disclosure;
fig. 1C is a schematic structural diagram of a short-circuit protection circuit according to an embodiment of the present disclosure;
fig. 2 is a schematic structural diagram of a control chip provided in an embodiment of the present application;
fig. 3 is a schematic structural diagram of a first ADC module and/or a second ADC module according to an embodiment of the present disclosure;
fig. 4A is a schematic structural diagram of a second amplifying module according to an embodiment of the present disclosure;
fig. 4B is a schematic structural diagram of a first amplification module according to an embodiment of the present disclosure;
fig. 5 is a schematic structural diagram of a short-circuit protection circuit according to an embodiment of the present disclosure;
fig. 6 is a schematic flowchart of a short-circuit protection method according to an embodiment of the present application.
Detailed Description
In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
The terms "first," "second," and the like in the description and claims of the present application and in the above-described drawings are used for distinguishing between different objects and not for describing a particular order. Furthermore, the terms "include" and "have," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may include other steps or elements not listed or inherent to such process, system, article, or apparatus in one possible example.
Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.
Referring to fig. 1A, a schematic structural diagram of a short-circuit protection circuit according to an embodiment of the present disclosure is shown, where the short-circuit protection circuit includes: a power supply 100, a control chip 200, a first resistor R1, a second resistor R2, and an output port 300, wherein,
one end 101 of the power source 100 is connected to the first port 201 of the control chip 200, the other end 102 of the power source 100 is connected to the input end of the first resistor R1 and the second port 202 of the control chip 200, the output end of the first resistor R1 is connected to the third port 203 of the control chip 200 and the first port 301 of the output port 300, the second resistor R2 is connected between the power source 100 and the output port 300, the input end of the second resistor R2 is connected to the fourth port 204 of the control chip 200, the output end of the second resistor R2 is connected to the fifth port 205 of the control chip 200, and the second port 302 of the output port 300 is grounded;
the control chip 200 is configured to detect and obtain a first voltage across the first resistor R1 and a second voltage across the second resistor R2;
the control chip 200 is further configured to determine a short-circuit condition of the first resistor R1 and/or the second resistor R2 according to the first voltage and the second voltage, and adjust the output voltage of the power supply 100 when the first resistor R1 and/or the second resistor R2 is short-circuited.
Wherein, the power supply may comprise at least one of the following: an AC (alternating current)/DC (direct current) charger power supply, a DC/DC power supply, and the like, without limitation.
The embodiment of the application is not only suitable for a flyback converter, but also suitable for switching power supply topologies such as a forward converter, a BUCK circuit, a BOOST circuit and an LLC resonant converter.
Wherein, the control chip may include at least one of the following: an MCU-embedded Integrated Circuit Chip (IC) such as IP2726 and IP2723T, IP2712 may be a System On Chip (SOC), and is not limited thereto.
Wherein, the resistance values of the first resistor R1 and the second resistor R2 can be the same or different, are not limited herein; the first resistor R1 and/or the second resistor R2 are output current detection resistors in the short-circuit protection circuit of the present application, and are mainly used for detecting the output current of the current 100.
The second resistor R2 may be connected between the power source 100 and the output port 300, that is, the second resistor R2 may be disposed in an output circuit of the power source 100, and a specific connection relationship between the second resistor R2 and the power source 100 and the output port 300 is not limited, and the connection relationship shown in fig. 4A is only one embodiment of the present disclosure.
The output terminal of the second resistor R2 is grounded, and the other terminal of the power supply 100 is also grounded.
The first resistor R1 is connected to the first port 101 of the power supply 100, and is configured to detect an output current at an upper end of the power supply 100; similarly, the second resistor R2 is connected to the second port 102 of the power supply 100, and can be used for detecting the output current of the lower end of the power supply 100.
In a specific implementation, the output current at the upper end of the power supply 100 can be determined by detecting the voltage difference between the two ends of the first resistor R1, i.e. the first voltage; the output current at the lower end of the power supply 100 can be determined by detecting the voltage difference across the second resistor R2, i.e., the second voltage.
The first resistor R1 and the second resistor R2 are connected in series.
In consideration of system loss generated by the output current detection resistor (i.e., the first resistor R1 and/or the second resistor R2), the first resistor R1 and/or the second resistor R2 are generally selected to have a smaller resistance value to reduce the loss.
The voltage across the first resistor R1 and/or the second resistor R2 can be detected by the control chip, so that the first current of the first resistor R1 and/or the second current flowing across the second resistor R2 can be obtained.
The working principle of the short-circuit protection circuit shown in fig. 1A is as follows: as shown in the figure, when the circuit works normally, the first resistor R1 and the second resistor R2 are in series, and the currents flowing through the first resistor R1 and the second resistor R2 are the same, that is, the first current is equal to the second current, that is, the currents output from the first port 101 and the second port 102 of the power supply 100 are the same; if any one component is short-circuited between the first resistor R1 and the second resistor R2, the first current corresponding to the first resistor R1 detected by the control chip 200 is different from the second current corresponding to the second resistor R2, and a large difference may occur, so that the control chip 200 may determine whether a component short-circuit condition occurs in the circuit according to the first current corresponding to the first resistor R1 and the second current corresponding to the second resistor R2, so as to determine whether a short-circuit protection state needs to be entered, and may enter the short-circuit protection state if the difference between the first current and the second current is large, specifically, the output voltage of the power supply may be adjusted, so that the output voltage of the power supply meets the LPS (power limit power supply) specification requirement, so as to achieve an effect of protecting the whole circuit.
It can be seen that, in the short-circuit protection circuit described in the embodiment of the present application, the power supply 100 can output current in two paths, and a mutual protection mechanism is established through a series relationship between two resistors (the first resistor R1 and the second resistor R2), so as to protect the whole circuit, when a short-circuit condition of a component occurs in the circuit, the output voltage of the power supply 100 can be adjusted to meet the requirement of the LPS standard, so as to prevent the component from being burned down due to an excessive output voltage of the power supply 100, thereby causing a fire hazard and the like, and being beneficial to ensuring the charging safety of a power supply use scene.
In one possible example, the second resistor is connected between the power supply and the output port, and includes: the input end of the second resistor R2 is connected to the second port 302 of the output port 300, the output end of the second resistor R2 is connected to the second port 302 of the output port 300, and the output end of the second resistor R2 is grounded.
Fig. 1A shows a connection relationship between the second resistor R2 and the power supply and the output port.
In one possible example, the second resistor R2 is connected between the power supply 100 and the output port 300, and includes: the input end of the second resistor R2 is connected to the first port 101 of the power supply 100, and the output end of the second resistor R2 is connected to the input end of the first resistor R1.
Fig. 1B is a schematic structural diagram of a short-circuit protection circuit, in which the connection relationship between the second resistor R2 and the power supply 100 and the output port 300 is different from that in fig. 1A, and the second resistor R2 and the first resistor R1 are in a series relationship.
In one possible example, the second resistor R2 is connected between the power supply 100 and the output port 300, and includes: the input end of the second resistor R2 is connected to the output end of the first resistor R1, and the output end of the second resistor R2 is connected to the first port 301 of the output port 300.
Fig. 1B is a schematic structural diagram of a short-circuit protection circuit, in which the connection relationship between the second resistor R2 and the power supply 100 and the output port 300 is different from that in fig. 1A and 1B, and the second resistor R2 and the first resistor R1 are in series.
In one possible example, please refer to fig. 2, fig. 2 is a schematic structural diagram of a control chip provided in an embodiment of the present application, where the control chip includes: an output control module 210, a first ADC module 220, a second ADC module 230, a first amplification module 240, and a second amplification module 250, wherein,
the first port 211 of the output control module 210 is connected to the power supply, the second port 212 of the output control module 210 is connected to the first port 221 of the first ADC module 220, the second port 222 of the first ADC module 220 is connected to the first port 241 of the first amplification module 240, the second port 242 of the first amplification module 240 is connected to the second port 202 of the control chip 200, and the third port 243 of the first amplification module 240 is connected to the third port 203 of the control chip 200.
The specific number of the first ADC (analog/digital conversion) modules and/or the second ADC modules is not limited, that is, the number of the ADC modules is not limited in the embodiment of the present application.
In the embodiment of the present application, the specific number of the first amplification (amplification sampling) module and/or the second amplification module is not limited, and the control chip may include 4, 5, or 6 amplification modules, and the like, which is not limited herein.
In the embodiment of the present application, in order to improve the sampling precision of the output current, a first amplification module 240 is added to a stage before the first ADC module 220 to amplify a sampling signal of the output current at the first resistor R1; a second amplification module 250 is added to a stage before the second ADC module 230 to amplify the sampled signal of the output current at the second resistor 300.
In one possible example, the third port 213 of the output control module 210 is connected to the first port 231 of the second ADC module 230, the second port 232 of the second ADC module 230 is connected to the first port 251 of the second amplification module 250, the second port 252 of the second amplification module 250 is connected to the fourth port 204 of the control chip 200, and the third port 253 of the second amplification module 250 is connected to the fifth port 205 of the control chip 200.
The output control module is configured to detect a first voltage across the first resistor R1 and a second voltage across the second resistor R2, and adjust the output voltage of the power supply 100, so that the control circuit enables the whole circuit to enter a short-circuit protection state when the first resistor R1 or the second resistor R2 is short-circuited, that is, the output voltage of the power supply 100 is adjusted to a preset voltage (e.g., 5V), and monitors the output state of the power supply 100 through a timer in a preset period, and keeps the maximum output current of the power supply to be a preset current (e.g., 500 mA).
In one possible example, please refer to fig. 3, where fig. 3 is a schematic structural diagram of a first ADC module and/or a second ADC module provided in an embodiment of the present application, where the first ADC module and/or the second ADC module include: a comparator, a sample-and-hold circuit, a Successive Approximation Register (SAR), and a Digital-to-Analog Converter (DAC), wherein,
one end of the sampling and holding circuit is connected with one end of the comparator, the other end of the comparator is connected with one end of the successive approximation register, the other end of the successive approximation register is connected with one end of the digital-to-analog converter, and the other end of the digital-to-analog converter is connected with the other end of the sampling and holding circuit and one end of the comparator.
The first ADC module and/or the second ADC module may employ a Successive Approximation Register (SAR) Analog-to-Digital Converter (ADC). The SAR ADC is also referred to as a binary search ADC.
The SAR ADC compares an analog input signal with an analog-to-digital conversion result obtained at the previous time through the DAC by using a high-speed high-precision comparator to obtain each Bit from a Most Significant Bit (MSB) to a Least Significant Bit (LSB), thereby converting each sampled analog signal of an output current into a digital signal of a plurality of bits.
In one possible example, the second amplification module 250 is different from the first amplification module 240.
If the connection relationship between the second resistor R2 and the power supply 100 and the output port 300 is as shown in fig. 1A, that is, the input end of the second resistor R2 is connected to the second port 302 of the output port 300, the output end of the second resistor R2 is connected to the second port 302 of the output port 300, and the output end of the second resistor R2 is grounded; then, in this case, the specific circuit of the second amplification block 250 described above is different from that of the first amplification block 240.
In one possible example, the second amplification module 250 is the same as the first amplification module 240.
If the connection relationship between the second resistor R2 and the power supply 100 and the output port 300 is as shown in fig. 1B or fig. 1C, the following steps are performed: the input end of the second resistor R2 is connected to the first port 101 of the power supply 100, the output end of the second resistor R2 is connected to the input end of the first resistor R1, or the input end of the second resistor R2 is connected to the output end of the first resistor R1, and the output end of the second resistor R2 is connected to the first port 301 of the output port 300. In the above case, the specific circuit of the second amplification block 250 is the same as that of the first amplification block 240.
In a possible example, please refer to fig. 4A, where fig. 4A is a schematic structural diagram of a second amplifying module provided in an embodiment of the present application, where the second amplifying module 250 includes: a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a first amplifier U1, a first MOS transistor Q1, a second MOS transistor Q2 and a third MOS transistor Q3, wherein,
one end of the third resistor R3 is connected to the input end of the second resistor R2, the third resistor R3 is connected to the forward input end of the first amplifier U1, the other end of the fourth resistor R4 is connected to the output end of the second resistor R2, the fourth resistor R4 is connected to the reverse input end of the first amplifier U1 and one end of the fifth resistor R5, the AVCC end of the first amplifier U1 is connected to the source of the first MOS transistor Q1 and the source of the second MOS transistor Q2, the gate of the first MOS transistor Q1 is connected to the gate of the second MOS transistor Q2 and the drain of the third MOS transistor Q3, the output end of the comparator U1 is connected to the gate of the third MOS transistor Q3, the source of the third MOS transistor Q3 is connected to the other end of the fifth resistor R5, the drain of the second MOS transistor Q2 is connected to one end of the sixth resistor R6 and the output end of the second ADC module 220, and the other end of the second resistor R6 is connected to ground.
The first MOS transistor and/or the second MOS transistor may also be a PNP-type transistor.
The first MOS tube and the second MOS tube are used for forming a mirror current source circuit, so that the current between the fifth resistor R5 and the sixth resistor R6 is equal, and therefore, the amplification factor of a current sampling signal in the circuit is the ratio of the voltage of the sixth resistor R6 to the voltage before the fifth resistor R5, namely R6/R5.
In one possible example, please refer to fig. 4B, where fig. 4B is a schematic structural diagram of a first amplification module 240 and/or a second amplification module 250 provided in an embodiment of the present application, where the first amplification module 240 includes: a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, a second amplifier U2, and a fourth MOS transistor Q4,
one end of the seventh resistor R7 is connected to the input end of the first resistor R1, the other end of the seventh resistor R7 is connected to the forward input end of the second amplifier U2 and one end of the ninth resistor R9, the other end of the ninth resistor R9 is connected to the drain of the fourth MOS transistor Q4, the gate of the fourth MOS transistor is connected to the output end of the second amplifier U2, the source of the fourth MOS transistor Q4 is connected to one end of the tenth resistor R10 and the output end of the first ADC module 220, and the other end of the tenth resistor R10 is grounded.
Based on the fact that the voltages of the positive input terminal + and the negative input terminal-of the second operational amplifier U2 are the same, the voltage difference across the seventh resistor R7 is equal to the sampled voltage, and the current across the seventh resistor R7 is equal to the current across the ninth resistor R9, so that the amplification factor of the current sampling signal is the ratio of the voltage across the ninth resistor R9 to the voltage across the seventh resistor R7, that is, the current sampling signal is amplified to be R9/R7.
In the embodiment of the present application, the first amplification module and/or the second amplification module may also be composed of other components, and the organization architecture thereof is not limited herein.
Alternatively, when the connection relationship between the second resistor R2 and the power supply 100 and the output port 300 is as shown in fig. 1A, the specific circuit of the first amplifying module 240 is as shown in fig. 4B, the specific circuit of the second amplifying module 250 is as shown in fig. 4A, and the second amplifying module 250 is different from the first amplifying module 240.
Alternatively, when the connection relationship between the second resistor R2 and the power supply 100 and the output port 300 is as shown in fig. 1B or 1C, the specific circuit of the first amplification module 240 and/or the second amplification module is as shown in fig. 4B, and the second amplification module 250 is the same as the first amplification module 240.
In one possible example, the output control module includes: the short-circuit protection circuit comprises a register and a timer, wherein the timer is used for monitoring the state of the output control module, and the register is used for resetting the short-circuit protection state of the output control module when the first resistor and/or the second resistor are/is short-circuited.
When the first resistor R1 or the second resistor R2 is short-circuited in the circuit, the duration of the short-circuited condition of the first resistor R1 or the second resistor R2 can be monitored through the timer.
The register may reset the state of the whole circuit after the duration of the short-circuit of the first resistor R1 and/or the second resistor R2 exceeds N clock cycles, that is, the register may control the power supply to output the normal voltage, release the short-circuit protection state, and restart monitoring whether the first resistor R1 and/or the second resistor R2 is short-circuited.
In one possible example, the output voltage of the power supply is regulated by:
and adjusting the output voltage of the power supply to be a preset voltage, monitoring the power supply through the timer in a preset period, and keeping the maximum output current of the power supply to be the preset current.
The preset voltage can be set by a user or defaulted by a system, and is not limited herein; the predetermined voltage may be set according to the LPS authentication protocol, and generally, the power supplies of the qualified LPS authentication protocol do not cause fire or electric shock because of limitations in the output current and voltage they deliver to the load. The following summarizes the specifications of a power supply that is certified as an inherent power supply delivery limitation LPS (VA = volt ampere, voc = open output voltage (no load), direct current voltage of 30Vdc or less or basic sinusoidal alternating current voltage of 30VACrms (Root-Mean-Square, effective value) or less): the maximum short-circuit current is 8A; maximum VA is 100; maximum tagged output power rating of 5a voc; the maximum tag output current rating is 5A. In the embodiment of the present application, in order to ensure that the power supply meets the LPS authentication requirements. The preset voltage may be set to 5V (volts) while the above-mentioned preset current is set to 500mA.
In a specific implementation, the output voltage of the power supply can be controlled by the control chip 200 to be adjusted to 5V, and the OCP point of the power supply is set to be adjusted to 500mA, so that the output current of the power supply can be limited to be lower than 500mA.
The OCP point is adjusted to limit current to realize an overcurrent protection function, and specifically, when the current in the loop is higher than the current limit point, the power supply 100 outputs a constant current at a set current limit value.
The preset period may be set by a user or default, and is not limited herein. The preset period may be N clock periods, where N is a positive integer, and the power supply 100 is kept outputting the output current lower than 500mA in the N clock periods.
In one possible example, the short circuit condition of the first resistance and/or the second resistance is determined by: determining a product of the resistance ratio and the first coefficient to obtain a first comparison value; determining a product of the resistance ratio and the second coefficient to obtain a second comparison value; if the voltage ratio is greater than the first comparison value, determining a first duration time that the voltage ratio is greater than the first comparison value through the timer, and if the first duration time is greater than or equal to a first preset threshold value, determining that the second resistor is short-circuited; and if the voltage ratio is smaller than the second comparison value, determining a second duration time that the voltage ratio is smaller than the second comparison value through the timer, and if the second duration time is larger than or equal to a second preset threshold value, determining that the first resistor is short-circuited.
The first coefficient and/or the second coefficient may be set by a user or default by a system, and are not limited herein; the value range of the first coefficient can also be preset as [ a, b ], and the value range of the second coefficient can be preset as [ c, d ]; the two ranges may be the same or different, wherein the first coefficient or the second coefficient may be taken from the ranges; the concrete is not limited herein; the first coefficient may be different from the second coefficient, and may be preset according to a specific sampling precision, for example, the first coefficient may be preset to 120%, and the second coefficient may be preset to 80%.
The first preset threshold and the second preset threshold may be set by a user or default in a system, for example, may be 5ms, 10ms, 15ms, 20ms, and the like, and specific values may be set according to actual application conditions, which is not limited herein.
In a specific implementation, the voltage of the first resistor R1 is determined to be V R1 Determining the voltage of the second resistor R2 as V R2 (ii) a If V R1 /V R2 >R 1 /R 2 X 120%, and the first duration is greater than or equal to a first preset threshold (e.g., 10 ms), then the second resistance R2 may be determined to be short; if V R1 /V R2 <R 1 /R 2 X 80%, and the second duration is greater than or equal to a second preset threshold (e.g., 10 ms), then it is determined that the first resistance R1 is short-circuited.
In one possible example, the output voltage of the power supply is regulated by:
if the first resistor R1 is determined to be short-circuited, adjusting the output voltage of the power supply 100;
if it is determined that the second resistor R2 is short-circuited, the output voltage of the power supply 100 is adjusted.
The output voltage of the power supply 100 can be adjusted to a preset voltage (for example, 5V) regardless of the short circuit of the first resistor or the second resistor, and the output state of the power supply 100 is monitored by a timer in a preset period, and the maximum output current of the power supply is kept to be a preset current (for example, 500 mA); thus, the short-circuit protection state is entered.
In one possible example, when the first resistor and/or the second resistor is short-circuited, the state of the output control module is reset by:
and after the maximum output current of the power supply is kept as the preset current for the preset period, resetting the short-circuit protection state of the output control module through the register.
In the embodiment of the present application, the preset period may be set by a user or default, and is not limited herein.
After the short-circuit protection state is maintained for a preset period, that is, after the maximum output current of the power supply is maintained as a preset current preset period, the short-circuit protection state of the output control module can be reset through the register, that is, the first voltage at two ends of the first resistor R1 and the second voltage at two ends of the second resistor R2 can be obtained through detection, the short-circuit condition of the first resistor and/or the second resistor is determined through the first voltage and the second voltage, and the output voltage of the power supply is adjusted when the first resistor and/or the second resistor is short-circuited, so that the whole circuit is protected cyclically.
Referring to fig. 5, fig. 5 is a schematic structural diagram of a short-circuit protection circuit according to an embodiment of the present disclosure, where the short-circuit protection circuit includes: a power supply 100, a control chip 200, a first resistor R1, a second resistor R2, and an output port 300, wherein,
one end 101 of the power source 100 is connected to the first port 201 of the control chip 200, the other end 102 of the power source 100 is connected to the input end of the first resistor R1 and the second port 202 of the control chip 200, the output end of the first resistor R1 is connected to the third port 203 of the control chip 200 and the first port 301 of the output port 300, the second resistor R2 is connected between the power source 100 and the output port 300, the input end of the second resistor R2 is connected to the fourth port 204 of the control chip 200, the output end of the second resistor R2 is connected to the fifth port 205 of the control chip 200, and the second port 302 of the output port 300 is grounded;
the control chip 200 is configured to detect and obtain a first voltage across the first resistor R1 and a second voltage across the second resistor R2;
the control chip 200 is further configured to determine a short-circuit condition of the first resistor R1 and/or the second resistor R2 according to the first voltage and the second voltage, and adjust the output voltage of the power supply 100 when the first resistor R1 and/or the second resistor R2 is short-circuited.
The control chip includes an output control module 210, a first ADC module 220, a second ADC module 230, a first amplification module 240, and a second amplification module 250.
As shown in fig. 5, the connection relationship between the second resistor R2, the power supply 100, and the output port 300 is shown in fig. 1A.
It can be seen that, in the short-circuit protection circuit described in the embodiment of the present application, the power supply 100 can output current in two paths, and a mutual protection mechanism is established through a series relationship between two resistors (the first resistor R1 and the second resistor R2), so as to protect the entire circuit, when a short-circuit condition of a component occurs in the circuit, the output control module 210 in the control chip 200 can adjust the output voltage of the power supply 100 to make the output voltage meet the requirement of the LPS standard, so as to prevent the component from being burned due to an excessively large output voltage of the power supply 100, thereby causing a fire and other conditions, and facilitating to ensure the charging safety in a power supply use scene.
Referring to fig. 6, a schematic flow chart of a short-circuit protection method according to an embodiment of the present disclosure is shown, where the short-circuit protection method is applied to the short-circuit protection circuit shown in fig. 1A, 1B, 1C, and 5, and the short-circuit protection circuit includes: the power supply comprises a power supply, a control chip, a first resistor, a second resistor and an output port, wherein one end of the power supply is connected with a first port of the control chip, the other end of the power supply is connected with an input end of the first resistor and a second port of the control chip, an output end of the first resistor is connected with a third port of the control chip and the output port, an input end of the second resistor is connected with a fourth port and the output port of the control chip, and an output end of the second resistor is connected with a fifth port of the control chip; the method comprises the following steps:
s601, detecting through the control chip to obtain a first voltage at two ends of the first resistor and a second voltage at two ends of the second resistor;
s602, determining the short circuit condition of the first resistor and/or the second resistor through the control chip according to the first voltage and the second voltage, and adjusting the output voltage of the power supply when the first resistor and/or the second resistor is short-circuited.
Therefore, in the short-circuit protection method described in the embodiment of the present application, a mutual protection mechanism may be established through a series relationship between two resistors (a first resistor and a second resistor), so as to protect the entire circuit, and when a short-circuit condition of a component occurs in the circuit, the output control module in the control chip may adjust the output voltage of the power supply to meet the requirement of the LPS standard, so as to prevent the component from being burned due to an excessive output voltage of the power supply, thereby causing a fire and the like, and being beneficial to ensuring the charging safety of the power supply in the usage scenario.
In one possible example, the determining of the short circuit condition of the first resistance and/or the second resistance may include: determining a voltage ratio between the first voltage and the second voltage; determining a resistance ratio between the first resistance and the second resistance; acquiring a first coefficient and a second coefficient, wherein the first coefficient and/or the second coefficient are/is used for constraining the resistance ratio; and determining the short circuit condition of the first resistor and/or the second resistor according to the voltage ratio, the resistance ratio, the first coefficient and the second coefficient.
In one possible example, the control chip includes: an output control module, the output control module comprising: a timer; the determining the short circuit condition of the first resistor and/or the second resistor according to the voltage ratio, the resistance ratio, the first coefficient and the second coefficient may include: determining a product of the resistance ratio and the first coefficient to obtain a first comparison value; determining a product of the resistance ratio and the second coefficient to obtain a second comparison value; if the voltage ratio is larger than the first comparison value, determining a first duration time of the voltage ratio larger than the first comparison value through the timer, and if the first duration time is larger than or equal to a first preset threshold value, determining that the second resistor is short-circuited; and if the voltage ratio is smaller than the second comparison value, determining a second duration time that the voltage ratio is smaller than the second comparison value through the timer, and if the second duration time is larger than or equal to a second preset threshold value, determining that the first resistor is short-circuited.
In one possible example, the adjusting the output voltage of the power supply may include: if the first resistor is determined to be short-circuited, adjusting the output voltage of the power supply; and if the second resistor is determined to be short-circuited, adjusting the output voltage of the power supply.
In one possible example, the adjusting the output voltage of the power supply may include: and adjusting the output voltage of the power supply to be a preset voltage, and keeping the maximum output current of the power supply to be a preset current through the timer in a preset period.
In one possible example, the output control module further comprises: a register; the method may further comprise the steps of: and after the maximum output current of the power supply is kept as the preset current for the preset period, resetting the short-circuit protection state of the output control module through the register.
It should be noted that the implementation manner of the above steps is the same as the specific steps in the short-circuit protection circuit, and is not described herein again.
The embodiment of the application provides a charging power supply, which comprises the short-circuit protection circuit provided by any application embodiment. The short-circuit protection circuit in the charging power supply is the same as the short-circuit protection circuit described in any of the embodiments of the above-mentioned application, and will not be described here.
The application provides an electronic device comprising a charging power supply.
The foregoing is only a partial embodiment of the present application, and it should be noted that, for those skilled in the art, several modifications and decorations can be made without departing from the principle of the present application, and these modifications and decorations should also be regarded as the protection scope of the present application.
Claims (10)
1. A short-circuit protection circuit, wherein the short-circuit protection is connected to a power supply, the short-circuit protection comprising: a control chip, a first resistor, a second resistor and an output port, wherein,
one end of the power supply is connected with a first port of the control chip, the other end of the power supply is connected with an input end of the first resistor and a second port of the control chip, an output end of the first resistor is connected with a third port of the control chip and a first port of the output port, the second resistor is connected between the power supply and the output port or the ground, an input end of the second resistor is connected with a fourth port of the control chip, an output end of the second resistor is connected with a fifth port of the control chip, and the second port of the output port is grounded;
the control chip is used for detecting and obtaining a first voltage at two ends of the first resistor and a second voltage at two ends of the second resistor;
the control chip is further configured to determine a short-circuit condition of the first resistor and/or the second resistor according to the first voltage and the second voltage, and adjust the output voltage of the power supply when the first resistor and/or the second resistor is short-circuited.
2. The circuit of claim 1,
the control chip includes:
an output control module, a first ADC module, a second ADC module, a first amplifying module and a second amplifying module,
the first port of the output control module is connected with the power supply, the second port of the output control module is connected with the first port of the first ADC module, the second port of the first ADC module is connected with the first port of the first amplification module, the second port of the first amplification module is connected with the second port of the control chip, and the third port of the first amplification module is connected with the third port of the control chip.
3. The circuit of claim 2, wherein a third port of the output control module is connected to the first port of the second ADC module, a second port of the second ADC module is connected to the first port of the second amplification module, a second port of the second amplification module is connected to the fourth port of the control chip, and a third port of the second amplification module is connected to the fifth port of the control chip.
4. The circuit of claim 2 or 3, wherein the first and/or second ADC module comprises: a comparator, a sample and hold circuit, a successive approximation register, and a digital-to-analog converter, wherein,
one end of the sampling and holding circuit is connected with one end of the comparator, the other end of the comparator is connected with one end of the successive approximation register, the other end of the successive approximation register is connected with one end of the digital-to-analog converter, and the other end of the digital-to-analog converter is connected with the other end of the sampling and holding circuit and one end of the comparator.
5. A circuit according to claim 2 or 3, wherein the second resistor is connected between the power supply and the output port, and comprises:
the input end of the second resistor is connected with the second port of the output port, the output end of the second resistor is connected with the second port of the output port, and the output end of the second resistor is grounded;
or, the second resistor is connected between the power supply and the output port, and includes: the input end of the second resistor is connected with the first port of the power supply, and the output end of the second resistor is connected with the input end of the first resistor;
or, the second resistor is connected between the power supply and the output port, and includes: the input end of the second resistor is connected with the output end of the first resistor, and the output end of the second resistor is connected with the first port of the output port.
6. The circuit of claim 5, wherein the second amplification module comprises: a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a first amplifier, a first MOS transistor, a second MOS transistor and a third MOS transistor,
one end of the third resistor is connected with the input end of the second resistor, the other end of the third resistor is connected with the forward input end of the first amplifier, the other end of the fourth resistor is connected with the output end of the second resistor, the fourth resistor is connected with the reverse input end of the first amplifier and one end of the fifth resistor, the AVCC end of the first amplifier is connected with the source electrode of the first MOS tube and the source electrode of the second MOS tube, the grid electrode of the first MOS tube is connected with the grid electrode of the second MOS tube and the drain electrode of the third MOS tube, the output end of the comparator is connected with the grid electrode of the third MOS tube, the source electrode of the third MOS tube is connected with the other end of the fifth resistor, the drain electrode of the second MOS tube is connected with one end of the sixth resistor and the output end of the second ADC module, and the other end of the sixth resistor is grounded.
7. The circuit of claim 5, wherein the first amplification module and/or the second amplification module comprises: a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, a second amplifier, and a fourth MOS transistor,
one end of the seventh resistor is connected with the input end of the first resistor, the other end of the seventh resistor is connected with the forward input end of the second amplifier and one end of the ninth resistor, the other end of the ninth resistor is connected with the drain electrode of the fourth MOS transistor, the grid electrode of the fourth MOS transistor is connected with the output end of the second amplifier, the source electrode of the fourth MOS transistor is connected with one end of the tenth resistor and the output end of the first ADC, and the other end of the tenth resistor is grounded.
8. A short-circuit protection method applied to the short-circuit protection circuit according to any one of claims 1 to 7, the method comprising:
detecting and obtaining a first voltage at two ends of the first resistor and a second voltage at two ends of the second resistor through the control chip;
and determining the short circuit condition of the first resistor and/or the second resistor through the control chip according to the first voltage and the second voltage, and adjusting the output voltage of the power supply when the first resistor and/or the second resistor are short-circuited.
9. A charging power supply characterized in that it comprises a short-circuit protection circuit according to any one of claims 1 to 8.
10. An electronic device characterized in that the electronic device comprises the charging power supply according to claim 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111258799.0A CN115549229A (en) | 2021-06-30 | 2021-06-30 | Short-circuit protection circuit and method, and related charging power supply and electronic equipment |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111258799.0A CN115549229A (en) | 2021-06-30 | 2021-06-30 | Short-circuit protection circuit and method, and related charging power supply and electronic equipment |
| CN202110733414.5A CN113178932B (en) | 2021-06-30 | 2021-06-30 | Short-circuit protection circuit, charging power supply and electronic equipment |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110733414.5A Division CN113178932B (en) | 2021-06-30 | 2021-06-30 | Short-circuit protection circuit, charging power supply and electronic equipment |
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| CN115549229A true CN115549229A (en) | 2022-12-30 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202111258799.0A Pending CN115549229A (en) | 2021-06-30 | 2021-06-30 | Short-circuit protection circuit and method, and related charging power supply and electronic equipment |
| CN202110733414.5A Active CN113178932B (en) | 2021-06-30 | 2021-06-30 | Short-circuit protection circuit, charging power supply and electronic equipment |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202110733414.5A Active CN113178932B (en) | 2021-06-30 | 2021-06-30 | Short-circuit protection circuit, charging power supply and electronic equipment |
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| CN (2) | CN115549229A (en) |
| WO (1) | WO2023272752A1 (en) |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008148496A (en) * | 2006-12-12 | 2008-06-26 | Matsushita Electric Ind Co Ltd | Charging apparatus |
| JP2009038865A (en) * | 2007-07-31 | 2009-02-19 | Panasonic Corp | Power supply device equipped with short circuit detecting function |
| CN101969188B (en) * | 2010-10-25 | 2013-08-21 | 灿芯半导体(上海)有限公司 | Resistor short-circuit protective device and protective method used for switching power supply |
| CN107579508B (en) * | 2017-09-23 | 2019-06-11 | 华为技术有限公司 | A kind of apparatus for protecting power supply and the terminal using described device |
| TWI701536B (en) * | 2018-09-26 | 2020-08-11 | 全漢企業股份有限公司 | Power apparatus, current detecting circuit and current detecting method |
| CN209134044U (en) * | 2018-10-26 | 2019-07-19 | 潍坊歌尔电子有限公司 | A kind of short-circuit protection circuit and electronic product |
| CN111769614A (en) * | 2020-07-09 | 2020-10-13 | 昂宝电子（上海）有限公司 | Detection circuit and method of quick charging system, quick charging protocol circuit and quick charging system |
| CN212343388U (en) * | 2020-07-10 | 2021-01-12 | 深圳英集芯科技有限公司 | Be used for battery charging outfit interface to ground short-circuit protection circuit |
| CN114336533B (en) * | 2020-10-10 | 2024-04-05 | 深圳英集芯科技股份有限公司 | Sampling resistor short-circuit protection circuit and quick charging charger |
-
2021
- 2021-06-30 CN CN202111258799.0A patent/CN115549229A/en active Pending
- 2021-06-30 CN CN202110733414.5A patent/CN113178932B/en active Active
- 2021-07-06 WO PCT/CN2021/104673 patent/WO2023272752A1/en unknown
Also Published As
| Publication number | Publication date |
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| CN113178932A (en) | 2021-07-27 |
| WO2023272752A1 (en) | 2023-01-05 |
| CN113178932B (en) | 2021-10-01 |
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