Voltage acquisition circuit and power supply equipment

Abstract

The invention discloses a voltage acquisition circuit and power supply equipment, the circuit comprises a voltage acquisition end, a near-end sampling unit, a far-end sampling unit, a voltage selection unit and an anomaly detection unit, and the voltage acquisition end is used for acquiring voltage signals. The near-end sampling unit is connected with an output port of the power supply equipment, and the near-end sampling unit is used for collecting the voltage of the output port of the power supply equipment to obtain a first voltage. The far-end sampling unit is connected with the power port of the load and is used for collecting the voltage of the power port of the load to obtain a second voltage. The voltage selection unit is connected with the near-end sampling unit, the voltage selection unit is connected with the far-end sampling unit, the voltage selection unit is connected with a voltage acquisition end, and the voltage selection unit is used for transmitting a target voltage to the voltage acquisition end. The abnormity detection unit is connected with the far-end sampling unit, and the abnormity detection unit is used for detecting a reverse connection fault or a disconnection fault of the far-end sampling unit.

Description

Technical Field

[0001] The present application relates to the technical field of power supply equipment, and in particular to a voltage acquisition circuit and a power supply equipment. Background Art

[0002] During the load test, the load needs to be charged by the power supply device. During the process of the power supply device outputting voltage, due to the line loss on the output line, there is a voltage difference between the output port of the power supply device and the input port of the product under test, resulting in reduced voltage accuracy. In order to solve this problem, the sampling point of the output port of the power supply device is moved outward to the input port of the load in the related art, which is called remote sampling. When the sampling line of remote sampling falls off or is connected in reverse, the constant voltage closed loop will be opened, which may cause the open circuit voltage output by the power supply device to be higher than the test voltage, thereby damaging the load. Summary of the invention

[0003] The present application aims to propose a voltage acquisition circuit and a power supply device, which can solve the problem of a sampling line dropping or being connected in reverse in remote sampling and damaging the load in traditional power supply device technology.

[0004] In a first aspect, an embodiment of the present application provides a voltage acquisition circuit, which is applied to a power supply device, wherein the power supply device is used to supply power to a load, and the circuit includes:

[0005] Voltage collection terminal, used for collecting voltage signals;

[0006] A proximal sampling unit, the proximal sampling unit is connected to the output port of the power supply device, and the proximal sampling unit is used to collect the voltage of the output port of the power supply device to obtain a first voltage;

[0007] A remote sampling unit, the remote sampling unit is connected to the power port of the load, and the remote sampling unit is used to collect the voltage of the power port of the load to obtain a second voltage;

[0008] a voltage selection unit, the voltage selection unit being connected to the proximal sampling unit, the voltage selection unit being connected to the distal sampling unit, the voltage selection unit being connected to the voltage acquisition terminal, the voltage selection unit being used to input a target voltage to the voltage acquisition terminal, if both the first voltage and the second voltage are input to the voltage selection unit, the target voltage is the smaller voltage between the first voltage and the second voltage, if only one of the first voltage and the second voltage is input to the voltage selection unit, the target voltage is the voltage input to the voltage selection unit;

[0009] An abnormality detection unit is connected to the remote sampling unit and is used to detect a reverse connection fault or a disconnection fault of the remote sampling unit. If the abnormality detection unit detects the reverse connection fault or the disconnection fault, the remote sampling unit is controlled to be disconnected.

[0010] According to some embodiments of the present application, the proximal sampling unit includes:

[0011] a first operational amplifier, wherein an output terminal of the first operational amplifier is connected to the voltage selection unit;

[0012] A first resistor, wherein the output port of the power supply device comprises a first positive power supply terminal and a first negative power supply terminal, one end of the first resistor is used to connect to the first positive power supply terminal, and the other end of the first resistor is connected to the non-inverting input terminal of the first operational amplifier;

[0013] a second resistor, one end of the second resistor being connected to the first negative power supply end, and the other end of the second resistor being connected to the inverting input end of the first operational amplifier;

[0014] A third resistor, wherein the non-inverting input terminal of the first operational amplifier is connected to one end of the third resistor, and the other end of the third resistor is grounded;

[0015] A fourth resistor, one end of the fourth resistor is connected to the output end of the first operational amplifier, and the other end of the fourth resistor is connected to the inverting input end of the first operational amplifier.

[0016] According to some embodiments of the present application, the remote sampling unit includes:

[0017] a second operational amplifier, wherein an output terminal of the second operational amplifier is connected to the voltage selection unit;

[0018] a fifth resistor, wherein the power supply port of the load includes a second positive power supply terminal and a second negative power supply terminal, one end of the fifth resistor is used to connect to the second positive power supply terminal, and the other end of the fifth resistor is connected to the non-inverting input terminal of the second operational amplifier;

[0019] a sixth resistor, one end of the sixth resistor being connected to the second negative power supply terminal, and the other end of the sixth resistor being connected to the inverting input terminal of the second operational amplifier;

[0020] a seventh resistor, wherein the non-inverting input terminal of the second operational amplifier is connected to one end of the seventh resistor, and the other end of the seventh resistor is grounded;

[0021] An eighth resistor, one end of the eighth resistor is connected to the output end of the second operational amplifier, and the other end of the eighth resistor is connected to the inverting input end of the second operational amplifier.

[0022] According to some embodiments of the present application, the voltage selection unit includes:

[0023] A third operational amplifier, wherein a non-inverting input terminal of the third operational amplifier is connected to the proximal sampling unit, and an inverting input terminal of the third operational amplifier is connected to the voltage collection terminal;

[0024] a first diode, wherein the output end of the third operational amplifier is connected to the cathode of the first diode;

[0025] a second diode, wherein the anode of the first diode is connected to the anode of the second diode, the cathode of the second diode is connected to the voltage collection end, and the anode of the second diode is connected to the power supply end;

[0026] A fourth operational amplifier, wherein a non-inverting input terminal of the fourth operational amplifier is connected to the remote sampling unit, and an inverting input terminal of the fourth operational amplifier is connected to the voltage collection terminal;

[0027] A third diode, the output end of the fourth operational amplifier is connected to the cathode of the third diode, and the anode of the third diode is connected to the anode of the second diode.

[0028] According to some embodiments of the present application, the abnormality detection unit includes:

[0029] a difference-finding subunit, the difference-finding subunit being connected to the proximal sampling unit, the difference-finding subunit being connected to the distal sampling unit, the difference-finding subunit being used to obtain a third voltage according to the first voltage and the second voltage, the third voltage being a voltage related to a difference between the first voltage and the second voltage;

[0030] A comparing subunit, the comparing subunit is connected to the difference finding subunit, and the comparing subunit is used to compare the third voltage with a preset reference voltage, and output a first control signal if the third voltage is greater than the reference voltage;

[0031] An execution subunit, wherein the execution subunit is connected to the comparison subunit, and the execution subunit is connected to the remote sampling unit. If the execution subunit receives the first control signal, the execution subunit controls the remote sampling unit to disconnect.

[0032] According to some embodiments of the present application, the difference obtaining subunit includes:

[0033] a fifth operational amplifier, wherein an output terminal of the fifth operational amplifier is connected to the comparison subunit;

[0034] a ninth resistor, wherein the non-inverting input terminal of the fifth operational amplifier is connected to one end of the ninth resistor, and the other end of the ninth resistor is connected to the proximal sampling unit;

[0035] a tenth resistor, wherein the non-inverting input terminal of the fifth operational amplifier is connected to one end of the tenth resistor, and the other end of the tenth resistor is grounded;

[0036] an eleventh resistor, an inverting input terminal of the fifth operational amplifier is connected to one end of the eleventh resistor, and the other end of the eleventh resistor is connected to the remote sampling unit;

[0037] A twelfth resistor, wherein the output end of the fifth operational amplifier is connected to one end of the twelfth resistor, and the other end of the twelfth resistor is connected to the inverting input end of the fifth operational amplifier.

[0038] According to some embodiments of the present application, the comparison subunit includes:

[0039] A sixth operational amplifier, wherein the non-inverting input terminal of the sixth operational amplifier is connected to the difference-finding subunit, the inverting input terminal of the sixth operational amplifier is used to input the reference voltage, and the output terminal of the sixth operational amplifier is connected to the execution subunit.

[0040] According to some embodiments of the present application, it further includes:

[0041] An alarm unit, the alarm unit is connected to the comparison subunit, and the alarm unit is used to output an alarm signal when receiving the first control signal.

[0042] According to some embodiments of the present application, the alarm unit includes:

[0043] A transistor, the base of the transistor is connected to the comparison subunit, the collector of the transistor is connected to the power supply end, the collector of the transistor is used to output the alarm signal, and the emitter of the transistor is grounded.

[0044] In a second aspect, an embodiment of the present application provides a power supply device, including the voltage acquisition circuit as described above.

[0045] In an embodiment of the present application, the voltage of the output port of the power supply device is collected by a proximal sampling unit to obtain a first voltage, and the voltage of the power supply port of the load is collected by a remote sampling unit to obtain a second voltage. If the abnormality detection unit detects that the remote sampling unit has a reverse connection fault or a disconnection fault, the remote sampling unit is controlled to disconnect, and the voltage selection unit outputs the first voltage to the voltage collection end to perform proximal sampling to avoid the constant voltage closed loop from forming an open circuit. If the wiring of the remote sampling unit is normal, the voltage selection unit outputs the smaller voltage of the first voltage and the second voltage, that is, the second voltage, to the voltage collection end to perform remote sampling normally. Compared with traditional power supply equipment technology, the embodiment of the present application avoids damage to the load and improves the safety of the test.

[0046] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The present application is further described below with reference to the accompanying drawings and embodiments, wherein:

[0048] Figure 1 A circuit diagram of an embodiment of a voltage acquisition circuit provided in the present application;

[0049] Figure 2 A circuit diagram of a voltage acquisition circuit provided in the present application in which a remote sampling unit has a reverse connection fault;

[0050] Figure 3 A circuit diagram of a voltage acquisition circuit embodiment provided in the present application in which a remote sampling unit has a disconnection fault. DETAILED DESCRIPTION

[0051] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0052] In the description of the present application, it should be understood that the descriptions involving orientation, such as the orientation or positional relationship indicated as up, down, etc., are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0053] In the description of this application, "a plurality" means more than two. If there is a description of "first" or "second", it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0054] In the description of this application, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in this application based on the specific content of the technical solution.

[0055] Refer to the following Figures 1 to 3 A voltage acquisition circuit and a power supply device according to an embodiment of the present application are described.

[0056] An embodiment of the present application provides a voltage acquisition circuit, which is applied to a power supply device, and the power supply device is used to supply power to a load, such as Figure 1 As shown, the circuit includes:

[0057] The voltage acquisition terminal Vsense is used to collect voltage signals;

[0058] A proximal sampling unit, the proximal sampling unit is connected to the output port of the power supply device, and the proximal sampling unit is used to collect the voltage of the output port of the power supply device to obtain a first voltage;

[0059] A remote sampling unit, the remote sampling unit is connected to the power port of the load, and the remote sampling unit is used to collect the voltage of the power port of the load to obtain a second voltage;

[0060] A voltage selection unit, the voltage selection unit is connected to the proximal sampling unit, the voltage selection unit is connected to the distal sampling unit, the voltage selection unit is connected to the voltage acquisition terminal Vsense, the voltage selection unit is used to input the target voltage to the voltage acquisition terminal Vsense, if the first voltage and the second voltage are both input to the voltage selection unit, the target voltage is the smaller voltage of the first voltage and the second voltage, if only one of the first voltage and the second voltage is input to the voltage selection unit, the target voltage is the voltage input to the voltage selection unit;

[0061] The abnormality detection unit is connected to the remote sampling unit. The abnormality detection unit is used to detect a reverse connection fault or a disconnection fault of the remote sampling unit. If the abnormality detection unit detects a reverse connection fault or a disconnection fault, the remote sampling unit is controlled to disconnect.

[0062] In the embodiment of the present application, the voltage of the output port of the power supply device is collected by the proximal sampling unit to obtain the first voltage, and the voltage of the power supply port of the load is collected by the remote sampling unit to obtain the second voltage. Figures 2 to 3 As shown, Figure 2This is a circuit diagram of a remote sampling unit with a reverse connection fault. Figure 3 The circuit diagram of the remote sampling unit having a disconnection fault is as follows: if the abnormal detection unit detects that the remote sampling unit has a reverse connection fault or a disconnection fault, the remote sampling unit is controlled to be disconnected, and the voltage selection unit outputs the first voltage to the voltage acquisition terminal Vsense to perform near-end sampling to avoid the constant voltage closed loop from forming an open circuit. If the remote sampling unit is wired normally, the voltage selection unit outputs the smaller voltage of the first voltage and the second voltage, i.e., the second voltage, to the voltage acquisition terminal Vsense to perform remote sampling normally. Compared with traditional power supply equipment technology, the embodiment of the present application avoids damage to the load and improves the safety of the test.

[0063] In some embodiments of the present application, the proximal sampling unit includes:

[0064] A first operational amplifier U1, wherein an output terminal of the first operational amplifier U1 is connected to a voltage selection unit;

[0065] A first resistor R3, the output port of the power supply device includes a first positive power supply terminal and a first negative power supply terminal, one end of the first resistor R3 is used to connect to the first positive power supply terminal, and the other end of the first resistor R3 is connected to the non-inverting input terminal of the first operational amplifier U1;

[0066] a second resistor R4, one end of the second resistor R4 is used to connect to the first negative power supply terminal, and the other end of the second resistor R4 is connected to the inverting input terminal of the first operational amplifier U1;

[0067] A third resistor R1, a non-inverting input terminal of the first operational amplifier U1 is connected to one end of the third resistor R1, and the other end of the third resistor R1 is grounded;

[0068] A fourth resistor R5 , one end of the fourth resistor R5 is connected to the output end of the first operational amplifier U1 , and the other end of the fourth resistor R5 is connected to the inverting input end of the first operational amplifier U1 .

[0069] In this embodiment, the first operational amplifier U1, the first resistor R3, the second resistor R4, the third resistor R1 and the fourth resistor R5 constitute a differential sampling circuit, the voltage of the first positive power supply terminal is input to the non-inverting input terminal of the first operational amplifier U1 through the first resistor R3, and the voltage of the first negative power supply terminal is input to the inverting input terminal of the first operational amplifier U1 through the second resistor R4. The first operational amplifier U1 performs differential sampling on the first positive power supply terminal and the first negative power supply terminal to obtain a first voltage.

[0070] The first resistor R3 and the second resistor R4 have the same resistance value, and the third resistor R1 and the fourth resistor R5 have the same resistance value. The magnitude of the first voltage can be calculated by the following formula:

[0071] V1=(Vlocal_P-Vlocal_N)*Ri1 / Ri3,

[0072] Wherein, V1 is the first voltage, Vlocal_P is the voltage of the first positive power supply terminal, Vlocal_N is the voltage of the first negative power supply terminal, Ri1 is the resistance value of the third resistor R1, and Ri3 is the resistance value of the first resistor R3.

[0073] In some embodiments of the present application, the remote sampling unit includes:

[0074] A second operational amplifier U3, wherein an output terminal of the second operational amplifier U3 is connected to a voltage selection unit;

[0075] A fifth resistor R8, the power supply port of the load includes a second positive power supply terminal and a second negative power supply terminal, one end of the fifth resistor R8 is used to connect to the second positive power supply terminal, and the other end of the fifth resistor R8 is connected to the non-inverting input terminal of the second operational amplifier U3;

[0076] a sixth resistor R9, one end of the sixth resistor R9 is used to connect to the second negative power supply terminal, and the other end of the sixth resistor R9 is connected to the inverting input terminal of the second operational amplifier U3;

[0077] A seventh resistor R7, a non-inverting input terminal of the second operational amplifier U3 is connected to one end of the seventh resistor R7, and the other end of the seventh resistor R7 is grounded;

[0078] An eighth resistor R10, one end of the eighth resistor R10 is connected to the output end of the second operational amplifier U3, and the other end of the eighth resistor R10 is connected to the inverting input end of the second operational amplifier U3.

[0079] In this embodiment, the second operational amplifier U3, the fifth resistor R8, the sixth resistor R9, the seventh resistor R7 and the eighth resistor R10 constitute a differential sampling circuit, the voltage of the second positive power supply terminal is input to the non-inverting input terminal of the second operational amplifier U3 through the fifth resistor R8, the voltage of the second negative power supply terminal is input to the inverting input terminal of the second operational amplifier U3 through the sixth resistor R9, the second operational amplifier U3 performs differential sampling on the second positive power supply terminal and the second negative power supply terminal, and the output terminal of the second operational amplifier U3 outputs the second voltage.

[0080] The first resistor R3, the second resistor R4, the fifth resistor R8 and the sixth resistor R9 have the same resistance value, and the third resistor R1, the fourth resistor R5, the seventh resistor R7 and the eighth resistor R10 have the same resistance value. When the remote sampling unit is connected normally, the magnitude of the second voltage can be calculated by the following formula:

[0081] V2=(Vremote_P-Vremote_N)*Ri1 / Ri3,

[0082] Wherein, V2 is the second voltage, Vremote_P is the voltage of the second positive power supply terminal, and Vremote_N is the voltage of the second negative power supply terminal.

[0083] When there is a reverse connection fault in the sampling line of the remote sampling unit, the magnitude of the second voltage can be calculated by the following formula:

[0084] V2=-(Vremote_P-Vremote_N)*Ri1 / Ri3,

[0085] When a line failure occurs on the sampling line of the remote sampling unit, the magnitude of the second voltage is zero.

[0086] In some implementations of the present application, the voltage selection unit includes:

[0087] A third operational amplifier U2, wherein a non-inverting input terminal of the third operational amplifier U2 is connected to the proximal sampling unit, and an inverting input terminal of the third operational amplifier U2 is connected to the voltage collection terminal Vsense;

[0088] The first diode D1, the output end of the third operational amplifier U2 is connected to the cathode of the first diode D1;

[0089] A second diode D2, an anode of the first diode D1 is connected to an anode of the second diode D2, a cathode of the second diode D2 is connected to a voltage collection terminal Vsense, and an anode of the second diode D2 is connected to a power supply terminal Vcc;

[0090] A fourth operational amplifier U4, wherein a non-inverting input terminal of the fourth operational amplifier U4 is connected to the remote sampling unit, and an inverting input terminal of the fourth operational amplifier U4 is connected to the voltage collection terminal Vsense;

[0091] The third diode D3, the output end of the fourth operational amplifier U4 is connected to the cathode of the third diode D3, and the anode of the third diode D3 is connected to the anode of the second diode D2.

[0092] In this embodiment, the first voltage is input to the non-inverting input terminal of the third operational amplifier U2, and the second voltage is input to the non-inverting input terminal of the fourth operational amplifier U4. The fourth operational amplifier U4 works in a negative feedback state, the first voltage is input to the non-inverting input terminal of the third operational amplifier U2, and the second voltage is input to the inverting input terminal of the third operational amplifier U2. When the source device works normally, due to the line loss on the output line, the first voltage must be greater than the second voltage. The third operational amplifier U2 works in a comparator state, the third operational amplifier U2 outputs a positive power rail, the first diode D1 is reversely cut off, the second diode D2 is turned on, the third diode D3 is turned on, and the fourth operational amplifier U4 outputs the second voltage to the voltage acquisition terminal Vsense to achieve remote sampling.

[0093] If the abnormality detection unit detects that the remote sampling unit has a reverse connection fault or a disconnection fault, the remote sampling unit is controlled to be disconnected, the third operational amplifier U2 operates in a negative feedback state, the first diode D1 and the second diode D2 are both turned on, and the third operational amplifier U2 outputs the first voltage to the voltage collection terminal Vsense to achieve near-end sampling.

[0094] In some implementations of the present application, the anomaly detection unit includes:

[0095] a difference-finding subunit, the difference-finding subunit is connected to the proximal sampling unit, the difference-finding subunit is connected to the distal sampling unit, and the difference-finding subunit is used to obtain a third voltage according to the first voltage and the second voltage, wherein the third voltage is a voltage related to the difference between the first voltage and the second voltage;

[0096] A comparing subunit, the comparing subunit is connected to the difference finding subunit, and the comparing subunit is used to compare the third voltage with a preset reference voltage Vset, and output a first control signal if the third voltage is greater than the reference voltage Vset;

[0097] The execution subunit is connected to the comparison subunit, and the execution subunit is connected to the remote sampling unit. If the execution subunit receives the first control signal, the execution subunit controls the remote sampling unit to disconnect.

[0098] In this embodiment, the difference-finding subunit obtains the third voltage according to the first voltage and the second voltage, and the comparison subunit compares the third voltage with a preset reference voltage Vset. When the remote sampling unit and the near-end sampling unit work normally, the difference between the first voltage and the second voltage is very small, so the third voltage is a very small voltage, and the reference voltage Vset is set to be greater than the third voltage in normal conditions. If the third voltage is greater than the reference voltage Vset, it indicates that there is a wiring fault or a reverse connection fault in the remote sampling unit, and the comparison subunit outputs a first control signal. The execution subunit receives the first control signal, and the execution subunit controls the remote sampling unit to disconnect.

[0099] In some implementations of the present application, the difference finding subunit includes:

[0100] A fifth operational amplifier U5, wherein the output end of the fifth operational amplifier U5 is connected to the comparison subunit;

[0101] A ninth resistor R14, a non-inverting input terminal of the fifth operational amplifier U5 is connected to one end of the ninth resistor R14, and the other end of the ninth resistor R14 is connected to the proximal sampling unit;

[0102] A tenth resistor R12, a non-inverting input terminal of the fifth operational amplifier U5 is connected to one end of the tenth resistor R12, and the other end of the tenth resistor R12 is grounded;

[0103] An eleventh resistor R15, an inverting input terminal of the fifth operational amplifier U5 is connected to one end of the eleventh resistor R15, and the other end of the eleventh resistor R15 is connected to the remote sampling unit;

[0104] The output end of the fifth operational amplifier U5 is connected to one end of the twelfth resistor R17, and the other end of the twelfth resistor R17 is connected to the inverting input end of the fifth operational amplifier U5.

[0105] In this embodiment, the first voltage is input to the non-inverting input terminal of the fifth operational amplifier U5 through the ninth resistor R14, and the second voltage is input to the inverting input terminal of the fifth operational amplifier U5 through the eleventh resistor R15. The fifth operational amplifier U5 calculates the difference between the first voltage and the second voltage to obtain a third voltage.

[0106] The resistance values ​​of the first resistor R3, the second resistor R4, the fifth resistor R8 and the sixth resistor R9 are equal, the resistance values ​​of the third resistor R1, the fourth resistor R5, the seventh resistor R7 and the eighth resistor R10 are equal, the resistance values ​​of the ninth resistor R14 and the eleventh resistor R15 are equal, and the resistance values ​​of the tenth resistor R12 and the twelfth resistor R17 are equal.

[0107] When both the local sampling unit and the remote sampling unit are working normally, the third voltage can be calculated by the following formula: V3 = (V1-V2)*R12 / R14 = [(Vlocal_P-Vlocal_N)-(Vremote_P-Vremote_N)]*Ri1*Ri12 / (Ri3*Ri14),

[0108] Among them, Ri12 is the resistance value of the tenth resistor R12, Ri14 is the resistance value of the ninth resistor R14, and (Vlocal_P-Vlocal_N)-(Vremote_P-Vremote_N) is a very small value, which is less than the reference voltage Vset.

[0109] When there is a reverse connection fault in the remote sampling unit, the third voltage can be calculated by the following formula:

[0110] V3 = (V1-V2)*Ri12 / Ri14 = [(Vlocal_P-Vlocal_N)+(Vremote_P-Vremote_N)]*Ri1*Ri12 / (Ri3*Ri14), wherein (Vlocal_P-Vlocal_N)+(Vremote_P-Vremote_N) is greater than the reference voltage Vset.

[0111] When there is a disconnection fault in the remote sampling unit, the third voltage can be calculated by the following formula:

[0112] V3=(V1-V2)*Ri12 / Ri14=(Vlocal_P-Vlocal_N)*Ri1*Ri12 / (Ri3*Ri14),

[0113] Wherein, (Vlocal_P-Vlocal_N) is greater than the reference voltage Vset.

[0114] In some embodiments of the present application, the comparison subunit includes:

[0115] The sixth operational amplifier U6, the non-inverting input terminal of the sixth operational amplifier U6 is connected to the difference-finding sub-unit, the inverting input terminal of the sixth operational amplifier U6 is used to input the reference voltage Vset, and the output terminal of the sixth operational amplifier U6 is connected to the execution sub-unit.

[0116] In this embodiment, the third voltage is input to the non-inverting input terminal of the sixth operational amplifier U6, and the reference voltage Vset is input to the inverting input terminal of the sixth operational amplifier U6. If the third voltage is greater than the reference voltage Vset, the output terminal of the sixth operational amplifier U6 outputs the positive power rail, that is, outputs the first control signal.

[0117] In some implementations of the present application, the execution subunit includes:

[0118] A fourth diode D4, an anode of the fourth diode D4 is connected to the output end of the sixth operational amplifier U6, and a cathode of the fourth diode D4 is connected to the output end of the second operational amplifier U3.

[0119] In this embodiment, if the third voltage is greater than the reference voltage Vset, the output end of the sixth operational amplifier U6 outputs the positive power rail to the fourth diode D4, the fourth diode D4 is turned on, the output end voltage of the second operational amplifier U3 is offset to the positive power rail, and the third diode D3 is turned off, thereby disconnecting the remote sampling unit.

[0120] When a remote sampling unit fails to connect or is reversed, the present application switches to near-end sampling. Due to the forward conductivity of the diode, the first diode D1, the second diode D2, and the third diode D3 of the voltage selection unit can quickly switch between near-end sampling and remote sampling, usually in the ns level. Since the diode voltage is unstable, the first diode D1, the second diode D2, and the third diode D3 are all set in a feedback closed loop, which can achieve us-level switching without losing measurement accuracy.

[0121] In some implementations of the present application, it also includes:

[0122] An alarm unit is connected to the comparison subunit, and is used for outputting an alarm signal when receiving the first control signal.

[0123] In some implementations of the present application, the alarm unit includes:

[0124] The transistor Q1 has a base connected to the comparison subunit, a collector connected to the power supply terminal Vcc, the collector of the transistor Q1 is used to output an alarm signal, and an emitter of the transistor Q1 is grounded.

[0125] In this embodiment, when the third voltage is greater than the reference voltage Vset, the output terminal of the sixth operational amplifier U6 outputs the positive power rail, that is, outputs the first control signal, the transistor Q1 is turned on, and since the emitter of the transistor Q1 is grounded, the collector of the transistor Q1 outputs a low voltage, that is, outputs an alarm signal to the fault detection terminal Vcheck, indicating that a disconnection fault or a reverse connection fault has occurred. When the third voltage is less than the reference voltage Vset, the transistor Q1 is not turned on, and the collector of the transistor Q1 outputs a high voltage signal to the fault detection terminal Vcheck, indicating that a disconnection fault and a reverse connection fault have not occurred.

[0126] In addition, an embodiment of the present application provides a power supply device, including the voltage acquisition circuit as described above.

[0127] The power supply device provided in the embodiment of the present application can implement each process implemented in the above-mentioned circuit embodiment and achieve the same beneficial effects. To avoid repetition, it will not be described here.

[0128] The embodiments of the present application are described in detail above in conjunction with the accompanying drawings, but the present application is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the purpose of the present application.

Claims

1. A voltage acquisition circuit, characterized in that: Applied to a power supply device, the power supply device is used to supply power to a load, and the circuit includes: Voltage collection terminal, used for collecting voltage signals; A proximal sampling unit, the proximal sampling unit is connected to the output port of the power supply device, and the proximal sampling unit is used to collect the voltage of the output port of the power supply device to obtain a first voltage; A remote sampling unit, the remote sampling unit is connected to the power port of the load, and the remote sampling unit is used to collect the voltage of the power port of the load to obtain a second voltage; a voltage selection unit, the voltage selection unit being connected to the proximal sampling unit, the voltage selection unit being connected to the distal sampling unit, the voltage selection unit being connected to the voltage acquisition terminal, the voltage selection unit being used to input a target voltage to the voltage acquisition terminal, if both the first voltage and the second voltage are input to the voltage selection unit, the target voltage is the smaller voltage between the first voltage and the second voltage, if only one of the first voltage and the second voltage is input to the voltage selection unit, the target voltage is the voltage input to the voltage selection unit; An abnormality detection unit is connected to the remote sampling unit and is used to detect a reverse connection fault or a disconnection fault of the remote sampling unit. If the abnormality detection unit detects the reverse connection fault or the disconnection fault, the remote sampling unit is controlled to disconnect.

2. The voltage acquisition circuit according to claim 1, characterized in that: The proximal sampling unit comprises: a first operational amplifier, wherein an output terminal of the first operational amplifier is connected to the voltage selection unit; A first resistor, wherein the output port of the power supply device comprises a first positive power supply terminal and a first negative power supply terminal, one end of the first resistor is used to connect to the first positive power supply terminal, and the other end of the first resistor is connected to the non-inverting input terminal of the first operational amplifier; a second resistor, one end of the second resistor being connected to the first negative power supply end, and the other end of the second resistor being connected to the inverting input end of the first operational amplifier; A third resistor, wherein the non-inverting input terminal of the first operational amplifier is connected to one end of the third resistor, and the other end of the third resistor is grounded; A fourth resistor, one end of the fourth resistor is connected to the output end of the first operational amplifier, and the other end of the fourth resistor is connected to the inverting input end of the first operational amplifier.

3. The voltage acquisition circuit according to claim 1, characterized in that: The remote sampling unit comprises: a second operational amplifier, wherein an output terminal of the second operational amplifier is connected to the voltage selection unit; a fifth resistor, wherein the power supply port of the load includes a second positive power supply terminal and a second negative power supply terminal, one end of the fifth resistor is used to connect to the second positive power supply terminal, and the other end of the fifth resistor is connected to the non-inverting input terminal of the second operational amplifier; a sixth resistor, one end of the sixth resistor being connected to the second negative power supply terminal, and the other end of the sixth resistor being connected to the inverting input terminal of the second operational amplifier; a seventh resistor, wherein the non-inverting input terminal of the second operational amplifier is connected to one end of the seventh resistor, and the other end of the seventh resistor is grounded; An eighth resistor, one end of the eighth resistor is connected to the output end of the second operational amplifier, and the other end of the eighth resistor is connected to the inverting input end of the second operational amplifier.

4. The voltage acquisition circuit according to claim 1, characterized in that: The voltage selection unit comprises: A third operational amplifier, wherein a non-inverting input terminal of the third operational amplifier is connected to the proximal sampling unit, and an inverting input terminal of the third operational amplifier is connected to the voltage collection terminal; a first diode, wherein the output end of the third operational amplifier is connected to the cathode of the first diode; a second diode, wherein the anode of the first diode is connected to the anode of the second diode, the cathode of the second diode is connected to the voltage collection end, and the anode of the second diode is connected to the power supply end; A fourth operational amplifier, wherein a non-inverting input terminal of the fourth operational amplifier is connected to the remote sampling unit, and an inverting input terminal of the fourth operational amplifier is connected to the voltage collection terminal; A third diode, the output end of the fourth operational amplifier is connected to the cathode of the third diode, and the anode of the third diode is connected to the anode of the second diode.

5. The voltage acquisition circuit according to claim 1, characterized in that: The abnormality detection unit comprises: a difference-finding subunit, the difference-finding subunit being connected to the proximal sampling unit, the difference-finding subunit being connected to the distal sampling unit, the difference-finding subunit being used to obtain a third voltage according to the first voltage and the second voltage, the third voltage being a voltage related to a difference between the first voltage and the second voltage; A comparing subunit, the comparing subunit is connected to the difference finding subunit, and the comparing subunit is used to compare the third voltage with a preset reference voltage, and output a first control signal if the third voltage is greater than the reference voltage; An execution subunit, wherein the execution subunit is connected to the comparison subunit, and the execution subunit is connected to the remote sampling unit. If the execution subunit receives the first control signal, the execution subunit controls the remote sampling unit to disconnect.

6. The voltage acquisition circuit according to claim 5, characterized in that: The difference finding subunit comprises: a fifth operational amplifier, wherein an output terminal of the fifth operational amplifier is connected to the comparison subunit; a ninth resistor, wherein the non-inverting input terminal of the fifth operational amplifier is connected to one end of the ninth resistor, and the other end of the ninth resistor is connected to the proximal sampling unit; a tenth resistor, wherein the non-inverting input terminal of the fifth operational amplifier is connected to one end of the tenth resistor, and the other end of the tenth resistor is grounded; an eleventh resistor, an inverting input terminal of the fifth operational amplifier is connected to one end of the eleventh resistor, and the other end of the eleventh resistor is connected to the remote sampling unit; A twelfth resistor, wherein the output end of the fifth operational amplifier is connected to one end of the twelfth resistor, and the other end of the twelfth resistor is connected to the inverting input end of the fifth operational amplifier.

7. The voltage acquisition circuit according to claim 5, characterized in that: The comparison subunit comprises: A sixth operational amplifier, wherein the non-inverting input terminal of the sixth operational amplifier is connected to the difference-finding subunit, the inverting input terminal of the sixth operational amplifier is used to input the reference voltage, and the output terminal of the sixth operational amplifier is connected to the execution subunit.

8. The voltage acquisition circuit according to claim 5, characterized in that: Also includes: An alarm unit, the alarm unit is connected to the comparison subunit, and the alarm unit is used to output an alarm signal when receiving the first control signal.

9. The voltage acquisition circuit according to claim 8, characterized in that: The alarm unit comprises: A transistor, the base of the transistor is connected to the comparison subunit, the collector of the transistor is connected to the power supply end, the collector of the transistor is used to output the alarm signal, and the emitter of the transistor is grounded.

10. A power supply device, characterized in that: The invention comprises the voltage acquisition circuit as claimed in any one of claims 1 to 9.

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