Current detection circuit and current detection equipment

Abstract

The utility model provides a current detection circuit and current detection equipment. The current detection circuit comprises a first controllable switch, a sleep current detection circuit, a working current detection circuit and a second controllable switch, in response to the first control signal, the first controllable switch controls the power supply to be connected to the tested equipment through the sleep current detection circuit, and the second controllable switch controls the sleep current detection circuit to output a sleep current detection signal to the measuring instrument; and in response to the second control signal, the first controllable switch controls the power supply to be connected to the tested equipment through the working current detection circuit, and the second controllable switch controls the working current detection circuit to output a working current detection signal to the measuring instrument. The current detection circuit is used for automatically detecting the working current and the sleep current of the detected equipment.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of current detection, in particular to a current detection circuit and a current detection device. BACKGROUND

[0002] For vehicle-mounted parts directly connected to the battery, there are generally two current requirements for the vehicle factory; one is that the working current consumption in the working state is within the controllable range, avoiding the melting of the fuse due to improper selection; the other is the non-working state, that is, the sleep mode, because it is directly connected to the battery, it needs to have very low consumption current to avoid the battery feeding caused by long-term placement.

[0003] Therefore, for vehicle-mounted parts, especially for vehicle-mounted power amplifiers which are directly connected to the battery and have particularly large power consumption, it is essential to test the working current and sleep current when leaving the factory. In order to improve the current detection efficiency of the vehicle-mounted power amplifier, it is very important to build a test tool for automatically detecting the working current and sleep current. CONTENT OF THE INVENTION

[0004] The present application provides a current detection circuit and a current detection device for automatically detecting the working current and sleep current of a device under test.

[0005] According to a first aspect of an embodiment of the present application, a current detection circuit is provided, comprising a first controllable switch, a sleep current detection circuit, a working current detection circuit and a second controllable switch;

[0006] In response to a first control signal, the first controllable switch controls the power supply to be connected to the device under test through the sleep current detection circuit, and the second controllable switch controls the sleep current detection circuit to output a sleep current detection signal to a measuring instrument;

[0007] In response to a second control signal, the first controllable switch controls the power supply to be connected to the device under test through the working current detection circuit, and the second controllable switch controls the working current detection circuit to output a working current detection signal to the measuring instrument.

[0008] Optionally, the sleep current detection circuit comprises a sleep current detection resistor and a sleep current detection amplifier;

[0009] The sleep current detection resistor is connected between the first controllable switch and the device under test; the sleep current detection amplifier and the sleep current detection resistor are connected in parallel; and the detection signal output end of the sleep current detection amplifier is connected to the second controllable switch.

[0010] The sleep current detection amplifier is configured to amplify the voltage drop on the sleep current detection resistor by a first amplification factor, and output a first amplified voltage to the second controllable switch.

[0011] Optionally, the working current detection circuit comprises a working current detection resistor and a working current detection amplifier.

[0012] The working current detection resistor is connected between the first controllable switch and the measured device; the working current detection amplifier and the working current detection resistor are connected in parallel; and a detection signal output end of the working current detection amplifier is connected to the second controllable switch.

[0013] The working current detection amplifier is configured to amplify the voltage drop on the working current detection resistor by a second amplification factor, and output a second amplified voltage to the second controllable switch.

[0014] Optionally, the current detection circuit further comprises a control unit.

[0015] The control unit is configured to output the first control signal or the second control signal.

[0016] Optionally, the first controllable switch comprises a first relay.

[0017] The control unit is connected to a coil of the first relay, a first contact of the first relay is connected to the power supply, a second contact of the first relay is connected to the measured device, the sleep current detection circuit is connected between a third contact and a fourth contact of the first relay, and the working current detection circuit is connected between a fifth contact and a sixth contact of the first relay.

[0018] The first relay is configured to, in response to the first control signal, control the first contact of the first relay to be connected to the third contact of the first relay, and control the second contact of the first relay to be connected to the fourth contact of the first relay; or, in response to the second control signal, control the first contact of the first relay to be connected to the fifth contact of the first relay, and control the second contact of the first relay to be connected to the sixth contact of the first relay.

[0019] Optionally, the second controllable switch comprises a second relay.

[0020] The control unit is connected to a coil of the second relay, a first contact of the second relay is connected to the measuring instrument, a second contact of the second relay is connected to a detection signal output end of the sleep current detection circuit, and a third contact of the second relay is connected to a detection signal output end of the working current detection circuit.

[0021] The second relay is configured to connect a first contact of the second relay to a second contact of the second relay in response to a first control signal, or to connect the first contact of the second relay to a third contact of the second relay in response to a second control signal.

[0022] Optionally, the control unit is specifically configured to output the first control signal to the second controllable switch after a preset time delay after outputting the first control signal to the first controllable switch, wherein the preset time delay is used to make the device under test enter a sleep mode.

[0023] Optionally, the device under test comprises a vehicle-mounted power amplifier.

[0024] According to a second aspect of the embodiments of the present application, a current detection device is provided, comprising at least one current detection circuit as described in the first aspect;

[0025] Different current detection circuits are used to detect the currents of different devices under test.

[0026] Optionally, the current detection circuits share one control unit, and the control unit is configured to output a first control signal or a second control signal.

[0027] The first control signal is used to control the current detection circuits to output respective sleep current detection signals to a measuring instrument.

[0028] The second control signal is used to control the current detection circuits to output respective working current detection signals to the measuring instrument.

[0029] In the application, the current detection circuit comprises a first controllable switch, a sleep current detection circuit, a working current detection circuit and a second controllable switch. When the first controllable switch and the second controllable switch receive a first control signal, the first controllable switch controls the power supply to connect to the measured device through the sleep current detection circuit, the second controllable switch controls the sleep current detection circuit to output a sleep current detection signal to the measuring instrument, the sleep current detection signal is measured through the measuring instrument to obtain the sleep current of the measured device, and then the sleep current of the measured device is automatically detected in response to the first control signal. When the first controllable switch and the second controllable switch receive a second control signal, the first controllable switch controls the power supply to connect to the measured device through the working current detection circuit, the second controllable switch controls the working current detection circuit to output a working current detection signal to the measuring instrument, the working current detection signal is measured through the measuring instrument to obtain the working current of the measured device, and then the working current of the measured device is automatically detected in response to the second control signal. Using the current detection circuit of the application, only the first control signal or the second control signal needs to be controlled to automatically detect the sleep current or the working current of the measured device, manual switching of the detection device is not required, the sleep current and the working current of the measured device can be automatically detected, and the efficiency of detecting the sleep current and the working current of the measured device is improved. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the provided drawings.

[0031] Figure 1 It is a structural schematic diagram of a circuit for detecting working current in the prior art;

[0032] Figure 2 It is a structural schematic diagram of a circuit for detecting sleep current in the prior art;

[0033] Figure 3 It is a structural schematic diagram of a current detection circuit provided in an embodiment of the present application;

[0034] Figure 4 It is a structural schematic diagram of a sleep current detection circuit provided in an embodiment of the present application;

[0035] Figure 5 It is a structural schematic diagram of a working current detection circuit provided in an embodiment of the present application;

[0036] Figure 6 It is a structural schematic diagram of a current detection circuit provided in an embodiment of the present application;

[0037] Figure 7 A structure diagram of a first relay provided in an embodiment of the present application;

[0038] Figure 8 A structure diagram of a second relay provided in an embodiment of the present application;

[0039] Figure 9 A structure diagram of a sleep current detection circuit provided in an embodiment of the present application;

[0040] Figure 10 A structure diagram of a working current detection circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0041] For vehicle parts, especially vehicle power amplifier which is directly connected to the battery and has particularly large power consumption, it is necessary to test the working current and sleep current when leaving the factory.

[0042] As shown in Figure 1 , it is a structure diagram of a circuit for detecting working current in the prior art. Figure 1 In the prior art, the regulated power supply is directly connected to the device under test, and the working current of the device under test is directly obtained by reading the display value of the regulated power supply.

[0043] As shown in Figure 2 , it is a structure diagram of a circuit for detecting sleep current in the prior art. Figure 2 In the prior art, the multimeter is connected between the regulated power supply and the device under test, and the bypass switch and the multimeter are connected in parallel. First, the bypass switch is closed, so that the regulated power supply is connected to the device under test through the bypass switch, then the device under test is woken up, and after a period of time, the device under test is put to sleep, the bypass switch is opened, so that the regulated power supply is connected to the device under test through the multimeter, and the sleep current of the device under test is measured through the multimeter.

[0044] Figure 1 and Figure 2 The functions of detecting the working current and sleep current of the device under test are realized, because the display value of the regulated power supply can be accurate to three decimal places, that is, the current of the order of milliamperes can be directly read. However, most vehicle parts require the sleep current to be below 100uA (microamperes), so the sleep current of the device under test cannot be directly obtained by reading the display value of the regulated power supply, while the working current can reach tens of amperes, and the working current of the device under test can be directly obtained by reading the display value of the regulated power supply. Figure 1 and Figure 2The scheme for detecting the working current and the sleep current of the device under test needs to detect the working current first, and then detect the sleep current through the multimeter and the bypass switch, needs to switch the detection device, the testing method is complicated, the testing efficiency is low, and the working current and the sleep current of the device under test cannot be automatically detected.

[0045] In order to realize automatic detection of the working current and the sleep current of the device under test, the application provides a current detection circuit and a current detection device.

[0046] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the application.

[0047] Exemplary current detection circuit

[0048] Please refer to Figure 3 In an exemplary embodiment, a current detection circuit is provided. As shown in Figure 3 The current detection circuit includes a first controllable switch 100, a sleep current detection circuit 200, a working current detection circuit 300, and a second controllable switch 400.

[0049] The first controllable switch 100 is connected between the power supply 500 and the sleep current detection circuit 200, the sleep current detection circuit 200 is connected between the first controllable switch 100 and the device under test 600, the first controllable switch 100 is connected between the power supply 500 and the working current detection circuit 300, the working current detection circuit 300 is connected between the first controllable switch 100 and the device under test 600, the second controllable switch 400 is connected between the detection signal output end of the sleep current detection circuit 200 and the measuring instrument 700, and the second controllable switch 400 is connected between the detection signal output end of the working current detection circuit 300 and the measuring instrument 700.

[0050] In response to the first control signal, the first controllable switch 100 controls the power supply 500 to be connected to the device under test 600 through the sleep current detection circuit 200, and the second controllable switch 400 controls the sleep current detection circuit 200 to output the sleep current detection signal to the measuring instrument 700;

[0051] In response to the second control signal, the first controllable switch 100 controls the power supply 500 to be connected to the device under test 600 through the working current detection circuit 300, and the second controllable switch 400 controls the working current detection circuit 300 to output the working current detection signal to the measuring instrument 700.

[0052] In the exemplary embodiment, the power supply 500 can be a regulated power supply or a battery, and this application does not limit it in this regard.

[0053] In the exemplary embodiment, the first controllable switch 100 and the second controllable switch 400 may include relays or other types of switching switches, as long as they can achieve switching between the two paths. This application does not limit the specific types of the first controllable switch 100 and the second controllable switch 400.

[0054] In an exemplary embodiment, the device under test 600 may include a vehicle power amplifier, or other devices that require detection of operating current and sleep current; this application does not limit this.

[0055] For automotive power amplifiers, which are directly connected to the battery and have particularly high power consumption, it is essential to test the operating current and sleep current at the factory. The current detection circuit in this application is particularly suitable for automotive power amplifiers.

[0056] In this application, the current detection circuit includes a first controllable switch, a dormant current detection circuit, a working current detection circuit, and a second controllable switch. When the first and second controllable switches receive a first control signal, the first controllable switch controls the power supply to connect to the device under test (DUT) through the dormant current detection circuit. The second controllable switch controls the dormant current detection circuit to output a dormant current detection signal to a measuring instrument. The measuring instrument measures the dormant current detection signal to obtain the dormant current of the DUT, thereby achieving automatic detection of the dormant current of the DUT in response to the first control signal. When the first and second controllable switches receive a second control signal, the first controllable switch controls the power supply to connect to the DUT through the working current detection circuit. The second controllable switch controls the working current detection circuit to output a working current detection signal to a measuring instrument. The measuring instrument measures the working current detection signal to obtain the working current of the DUT, thereby achieving automatic detection of the working current of the DUT in response to the second control signal. Using the current detection circuit of this application, only the first control signal or the second control signal needs to be controlled to automatically detect the dormant current or operating current of the device under test. There is no need to manually switch the detection device, which can automatically detect the dormant current and operating current of the device under test, thus improving the efficiency of detecting the dormant current and operating current of the device under test.

[0057] In some embodiments, such as Figure 4 As shown, the sleep current detection circuit 200 includes a sleep current detection resistor 210 and a sleep current detection amplifier 220.

[0058] The standby current detection resistor 210 is connected between the first controllable switch 100 and the device under test 600; the standby current detection amplifier 220 is connected in parallel with the standby current detection resistor 210; and the detection signal output end of the standby current detection amplifier 220 is connected to the second controllable switch 400.

[0059] The standby current detection amplifier 220 is configured to amplify the voltage drop on the standby current detection resistor 210 by a first amplification factor and output a first amplified voltage to the second controllable switch 400.

[0060] In an exemplary embodiment, the standby current detection resistor 210 can be a resistor with a resistance of 1Ω, packaged as 3550, a power of 5W, and an accuracy of 1%. According to needs, the standby current detection resistor 210 can also be a resistor with other resistance values, and the present application does not limit this.

[0061] In an exemplary embodiment, the standby current detection amplifier 220 can be a current detection amplifier TP182A4, or other types of current detection amplifiers, and the present application does not limit this.

[0062] In an exemplary embodiment, the first amplification factor can be 500 times, or other values, and the present application does not limit this.

[0063] In an exemplary embodiment, the standby current detection resistor 210 can be connected in parallel with the standby current detection amplifier 220 by a Kelvin connection method, which is a simple method for eliminating the voltage drop on the wires in the circuit.

[0064] In an exemplary embodiment, the first amplified voltage is the standby current detection signal.

[0065] In an exemplary embodiment, the standby current is assumed to be 100uA, the voltage drop on the standby current detection resistor 210 with a resistance of 1Ω is 0.1mV, the first amplification factor is 500 times, and the output first amplified voltage is 0.05V. After the multimeter reads 0.05V, the standby current to be detected is converted by a preset formula.

[0066] The standby current detection amplifier 220 amplifies the voltage drop on the standby current detection resistor 210 by a first amplification factor and outputs a first amplified voltage to the second controllable switch 400, which is convenient for the measuring instrument 700 to read, and thus the standby current is obtained, and the detection accuracy of the standby current is improved.

[0067] In an exemplary embodiment, the test error of the standby current is controlled within 1%.

[0068] In some embodiments, as Figure 5As shown, the working current detection circuit 300 comprises a working current detection resistor 310 and a working current detection amplifier 320;

[0069] The working current detection resistor 310 is connected between the first controllable switch 100 and the device under test 600; the working current detection amplifier 320 is connected in parallel with the working current detection resistor 310; the detection signal output end of the working current detection amplifier 320 is connected to the second controllable switch 400;

[0070] The working current detection amplifier 320 is configured to amplify the voltage drop on the working current detection resistor 310 by a second amplification factor, and output the amplified second voltage to the second controllable switch 400.

[0071] In the exemplary embodiment, the working current detection resistor 310 can be a resistor with a resistance of 2 mΩ, packaged as 1206, with a power of 1 / 4 W and an accuracy of 1%. According to the needs, the working current detection resistor 310 can also be selected from other resistors with different resistance values, and the present application does not limit this.

[0072] In the exemplary embodiment, the working current detection amplifier 320 can be a current detection amplifier TP182A2, or other models of current detection amplifiers can also be selected, and the present application does not limit this.

[0073] In the exemplary embodiment, the second amplification factor can be 100 times, or other values of amplification factor, and the present application does not limit this.

[0074] In the exemplary embodiment, the working current detection resistor 310 can be connected in parallel with the working current detection amplifier 320 through the Kelvin connection method, which is a simple method to eliminate the voltage drop on the wires in the circuit.

[0075] In the exemplary embodiment, the amplified second voltage is the working current detection signal.

[0076] In the exemplary embodiment, the working current is assumed to be 5A, at this time the voltage drop on the working current detection resistor 310 with a resistance of 2 mΩ is 10 mV, the second amplification factor is 100 times, and the output amplified second voltage is 1V. After the multimeter reads 1V, the working current to be measured is converted through the preset formula.

[0077] The working current detection amplifier 320 amplifies the voltage drop on the working current detection resistor 310 by a second amplification factor, and outputs the amplified second voltage to the second controllable switch 400. The amplified second voltage is convenient for the measuring instrument 700 to read, and the working current is obtained, and the detection accuracy of the working current is improved.

[0078] In the example embodiment, the test error of the working current is controlled within 1%.

[0079] In some embodiments, as shown in Figure 6 The current detection circuit includes a first controllable switch 100, a sleep current detection circuit 200, a working current detection circuit 300, a second controllable switch 400, and a control unit 800.

[0080] The first controllable switch 100 is connected between the power supply 500 and the sleep current detection circuit 200, the sleep current detection circuit 200 is connected between the first controllable switch 100 and the device under test 600, the first controllable switch 100 is connected between the power supply 500 and the working current detection circuit 300, the working current detection circuit 300 is connected between the first controllable switch 100 and the device under test 600, the second controllable switch 400 is connected between the detection signal output end of the sleep current detection circuit 200 and the measuring instrument 700, and the second controllable switch 400 is connected between the detection signal output end of the working current detection circuit 300 and the measuring instrument 700.

[0081] The control unit 800 is connected to the control end of the first controllable switch 100, and the control unit 800 is connected to the control end of the second controllable switch 400.

[0082] The control unit 800 is configured to output a first control signal or a second control signal.

[0083] In response to the first control signal, the first controllable switch 100 controls the power supply 500 to connect to the device under test 600 through the sleep current detection circuit 200, and the second controllable switch 400 controls the sleep current detection circuit 200 to output a sleep current detection signal to the measuring instrument 700.

[0084] In response to the second control signal, the first controllable switch 100 controls the power supply 500 to connect to the device under test 600 through the working current detection circuit 300, and the second controllable switch 400 controls the working current detection circuit 300 to output a working current detection signal to the measuring instrument 700.

[0085] In the example embodiment, the control unit 800 can be a single-chip microcomputer with RS485 communication, and the single-chip microcomputer outputs the first control signal or the second control signal under the control of the upper computer. The control unit 800 can also be other types of control units as long as it can output the first control signal or the second control signal, and the present application does not limit this.

[0086] The control unit outputs a first control signal or a second control signal. When the first controllable switch and the second controllable switch receive the first control signal, the first controllable switch controls the power supply to be connected to the device under test through the sleep current detection circuit, and the second controllable switch controls the sleep current detection circuit to output a sleep current detection signal to the measuring instrument, so that the sleep current of the device under test is obtained by measuring the sleep current detection signal through the measuring instrument, thereby realizing automatic detection of the sleep current of the device under test in response to the first control signal. When the first controllable switch and the second controllable switch receive the second control signal, the first controllable switch controls the power supply to be connected to the device under test through the working current detection circuit, and the second controllable switch controls the working current detection circuit to output a working current detection signal to the measuring instrument, so that the working current of the device under test is obtained by measuring the working current detection signal through the measuring instrument, thereby realizing automatic detection of the working current of the device under test in response to the second control signal. By using the current detection circuit of the present application, only the first control signal or the second control signal needs to be output by the control unit, so that the sleep current or the working current of the device under test can be automatically detected, manual switching of the detection device is not required, the sleep current and the working current of the device under test can be automatically detected, and the efficiency of detecting the sleep current and the working current of the device under test is improved.

[0087] In some embodiments, as shown in Figure 7 The first controllable switch 100 includes a first relay 110.

[0088] The control unit 800 is connected to the coil of the first relay 110, the first contact of the first relay 110 is connected to the power supply 500, the second contact of the first relay 110 is connected to the device under test 600, the sleep current detection circuit 200 is connected between the third contact and the fourth contact of the first relay 110, and the working current detection circuit 300 is connected between the fifth contact and the sixth contact of the first relay 110.

[0089] The first relay 110 is configured to, in response to the first control signal, control the first contact of the first relay 110 to be connected to the third contact of the first relay 110, and control the second contact of the first relay 110 to be connected to the fourth contact of the first relay 110; or, in response to the second control signal, control the first contact of the first relay 110 to be connected to the fifth contact of the first relay 110, and control the second contact of the first relay 110 to be connected to the sixth contact of the first relay 110.

[0090] In response to the first control signal, the first control unit 800 controls the first contact of the first relay 110 to connect to the third contact of the first relay 110, and controls the second contact of the first relay 110 to connect to the fourth contact of the first relay 110, at this time, the power supply 500 is connected to the device under test 600 through the sleep current detection circuit 200. In response to the second control signal, the first control unit 800 controls the first contact of the first relay 110 to connect to the fifth contact of the first relay 110, and controls the second contact of the first relay 110 to connect to the sixth contact of the first relay 110, at this time, the power supply 500 is connected to the device under test 600 through the working current detection circuit 300.

[0091] In the exemplary embodiment, the first contact and the second contact of the first relay 110 are movable contacts, and the third contact, the fourth contact, the fifth contact and the sixth contact of the first relay 110 are fixed contacts. The first control unit 800 controls the energization or de-energization of the coil of the first relay 110 to control the first contact of the first relay 110 to connect to the third contact of the first relay 110, and controls the second contact of the first relay 110 to connect to the fourth contact of the first relay 110, or controls the first contact of the first relay 110 to connect to the fifth contact of the first relay 110, and controls the second contact of the first relay 110 to connect to the sixth contact of the first relay 110.

[0092] In some embodiments, as shown in FIG. 2, the second controllable switch 400 includes a second relay 410. Figure 8

[0093] The first control unit 800 is connected to the coil of the second relay 410, the first contact of the second relay 410 is connected to the measuring instrument 700, the second contact of the second relay 410 is connected to the detection signal output end of the sleep current detection circuit 200, and the third contact of the second relay 410 is connected to the detection signal output end of the working current detection circuit 300.

[0094] The second relay 410 is configured to, in response to the first control signal, control the first contact of the second relay 410 to connect to the second contact of the second relay 410, or, in response to the second control signal, control the first contact of the second relay 410 to connect to the third contact of the second relay 410.

[0095] In response to the first control signal, the first control unit 800 controls the first contact of the second relay 410 to connect to the second contact of the second relay 410, at this time, the detection signal output end of the sleep current detection circuit 200 is connected to the measuring instrument 700. In response to the second control signal, the first control unit 800 controls the first contact of the second relay 410 to connect to the third contact of the second relay 410, at this time, the detection signal output end of the working current detection circuit 300 is connected to the measuring instrument 700.

[0096] ​In the exemplary embodiment, the first contact of the second relay 410 is a moving contact, and the second and third contacts of the second relay 410 are stationary contacts. The control unit 800 controls the coil of the second relay 410 to be energized or de-energized, thereby controlling the first contact of the second relay 410 to be connected to the second contact of the second relay 410, or controlling the first contact of the second relay 410 to be connected to the third contact of the second relay 410.

[0097] In some embodiments, the control unit 800 is specifically configured to output a first control signal to a second controllable switch 400 after a preset time delay after outputting a first control signal to a first controllable switch 100, wherein the preset time is used to enable the device under test 600 to enter a sleep mode.

[0098] In the exemplary embodiment, the preset duration can be 5 seconds. As needed, the preset duration can also be other values, and this application does not limit this.

[0099] In the exemplary embodiment, after the first control signal is output to the first controllable switch 100, the device under test 600 is woken up. The device under test 600 does not send CAN (Controller Area Network) messages and waits for 5 seconds before entering sleep mode.

[0100] After outputting the first control signal to the first controllable switch 100, the control unit 800 delays for a preset time and then outputs the first control signal to the second controllable switch 400. The preset time is used to enable the device under test 600 to enter a sleep mode. After entering the sleep mode, the sleep current of the device under test 600 is measured.

[0101] In an exemplary embodiment, such as Figure 9 The diagram shown is a schematic of a sleep current detection circuit. Figure 9 In the circuit, the sleep current detection resistor 210 is R4, BAT_IN_1 is the connection terminal connected to the third contact of the first relay 110, BAT_OUT_1 is the connection terminal connected to the fourth contact of the first relay 110, the sleep current detection amplifier 220 is U1, the detection signal output terminal of the sleep current detection amplifier 220 is OUT1, and OUT_1 is the connection terminal connected to the second contact of the second relay 410. Figure 9 The other resistors and capacitors shown are also part of the sleep current detection circuit.

[0102] In an exemplary embodiment, such as Figure 10 The diagram shown is a schematic of a working current detection circuit. Figure 10In the specific embodiment, the working current detection resistor 310 is R5, the BAT_IN_2 is a connection end connected with the fifth contact of the first relay 110, the BAT_OUT_2 is a connection end connected with the sixth contact of the first relay 110, the working current detection amplifier 320 is U2, the detection signal output end of the working current detection amplifier 320 is OUT2, and the OUT_2 is a connection end connected with the third contact of the second relay 410. Figure 10 The other resistors and capacitors shown in the specific embodiment are also part of the working current detection circuit.

[0103] Exemplary current detection device

[0104] Correspondingly, the application also provides a current detection device, which comprises at least one current detection circuit provided by any of the above embodiments.

[0105] Different current detection circuits are used to detect the currents of different devices under test.

[0106] The current detection device provided by the application can detect the currents of multiple devices under test at the same time, and the currents include sleep currents and working currents, thereby improving the detection efficiency of the currents of multiple devices under test.

[0107] In the exemplary embodiment, the current detection device comprises six current detection circuits provided by any of the above embodiments, and the current detection device can also comprise other numbers of current detection circuits, which are not limited by the application.

[0108] In some embodiments, the current detection circuits share the same control unit, and the control unit is configured to output a first control signal or a second control signal.

[0109] The first control signal is configured to control the current detection circuits to output respective sleep current detection signals to the measuring instrument.

[0110] The second control signal is configured to control the current detection circuits to output respective working current detection signals to the measuring instrument.

[0111] By sharing the same control unit, the number of control units in the current detection device can be reduced, thereby reducing the cost of the current detection device.

[0112] Technical details not described in the specific embodiment can refer to the specific content of the current detection circuit provided by the above embodiments, which will not be described here.

[0113] It should be noted that each of the embodiments in the specification is described in progressive manner, and each embodiment focuses on the difference from other embodiments, and the same and similar parts between the embodiments can be mutually referred to.

[0114] The modules and circuits in the embodiments of the present application can be combined, divided, and deleted according to actual needs.

[0115] Finally, it should be noted that in this document, the relationship terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "include", "contain" or any other variants are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or equipment. Without more limitations, the element defined by the statement "including a" does not exclude the presence of other identical elements in the process, method, article or equipment including the element.

[0116] The above description of the disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to the embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A current detection circuit, characterized by, The current detection circuit comprises a first controllable switch, a sleep current detection circuit, a working current detection circuit and a second controllable switch. In response to a first control signal, the first controllable switch controls the power supply to be connected to the device under test through the sleep current detection circuit, and the second controllable switch controls the sleep current detection circuit to output a sleep current detection signal to a measuring instrument. In response to a second control signal, the first controllable switch controls the power supply to be connected to the device under test through the working current detection circuit, and the second controllable switch controls the working current detection circuit to output a working current detection signal to the measuring instrument.

2. The current sense circuit of claim 1, wherein, The sleep current detection circuit comprises a sleep current detection resistor and a sleep current detection amplifier. The sleep current detection resistor is connected between the first controllable switch and the device under test, and the sleep current detection amplifier is connected in parallel with the sleep current detection resistor. The sleep current detection amplifier is connected to the second controllable switch. The sleep current detection amplifier is configured to amplify a voltage drop on the sleep current detection resistor by a first amplification factor and output a first amplified voltage to the second controllable switch.

3. The current sense circuit of claim 1, wherein, The working current detection circuit comprises a working current detection resistor and a working current detection amplifier. The working current detection resistor is connected between the first controllable switch and the device under test, and the working current detection amplifier is connected in parallel with the working current detection resistor. The working current detection amplifier is connected to the second controllable switch. The working current detection amplifier is configured to amplify a voltage drop on the working current detection resistor by a second amplification factor and output a second amplified voltage to the second controllable switch.

4. The current sense circuit of claim 1, wherein, The current detection circuit further comprises a control unit. The control unit is configured to output the first control signal or the second control signal.

5. The current sense circuit of claim 4, wherein, The first controllable switch comprises a first relay. The control unit is connected to a coil of the first relay. A first contact of the first relay is connected to the power supply, a second contact of the first relay is connected to the device under test, the sleep current detection circuit is connected between a third contact and a fourth contact of the first relay, and the working current detection circuit is connected between a fifth contact and a sixth contact of the first relay. The first relay is configured to, in response to the first control signal, control the first contact of the first relay to be connected to the third contact of the first relay and control the second contact of the first relay to be connected to the fourth contact of the first relay; or, in response to the second control signal, control the first contact of the first relay to be connected to the fifth contact of the first relay and control the second contact of the first relay to be connected to the sixth contact of the first relay.

6. The current sense circuit of claim 4, wherein, The second controllable switch comprises a second relay. The control unit is connected to a coil of the second relay, a first contact of the second relay is connected to the measuring instrument, a second contact of the second relay is connected to a detection signal output end of the sleep current detection circuit, and a third contact of the second relay is connected to a detection signal output end of the working current detection circuit. The second relay is configured to, in response to a first control signal, control the first contact of the second relay to be connected to the second contact of the second relay, or, in response to a second control signal, control the first contact of the second relay to be connected to the third contact of the second relay.

7. The current sense circuit of claim 4, wherein, The control unit is specifically configured to, after outputting the first control signal to the first controllable switch, delay for a preset time length, and output the first control signal to the second controllable switch, wherein the preset time length is used to make the device under test enter a sleep mode.

8. The current sense circuit according to any one of claims 1 to 7, wherein, The device under test includes a vehicle-mounted power amplifier.

9. A current detection device, characterized by, The current detection circuit includes at least one current detection circuit as claimed in any one of claims 1 to 8. Different current detection circuits are used to detect currents of different devices under test.

10. The current sensing device of claim 9, wherein, The current detection circuits share the same control unit, and the control unit is used to output a first control signal or a second control signal. The first control signal is used to control the current detection circuits to output respective sleep current detection signals to the measuring instrument. The second control signal is used to control the current detection circuits to output respective working current detection signals to the measuring instrument.

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