CN116799743A - Overcurrent protection circuit of medical equipment and overcurrent protection method thereof - Google Patents
Overcurrent protection circuit of medical equipment and overcurrent protection method thereof Download PDFInfo
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Abstract
The utility model provides an overcurrent protection circuit and overcurrent protection method of medical equipment, belongs to the electrical field of medical equipment, including sampling resistor in the current protection circuit, sampling resistor is connected with the homophase input of amplifier circuit, and amplifier circuit's public end is connected to comparison circuit, and comparison circuit output is connected with first control circuit, is connected with second control circuit on the first control circuit, is connected with the auto-lock circuit on the first control circuit with the second control circuit between, is connected with analog switch behind the second control circuit, and the auto-lock circuit controls second control circuit and analog switch's switching on and off, reaches control to the switching on or off of load, can avoid the overcurrent to damage equipment, simultaneously, can reduce equipment cost, improves the flexibility in the medical equipment use.
Description
Technical Field
The invention relates to a protection circuit and an overcurrent protection method thereof, in particular to an overcurrent protection circuit of medical equipment and an overcurrent protection method thereof, belonging to the electrical field of the medical equipment.
Background
With the progress of society, more and more intelligent devices replace people to complete a series of work, such as sweeping, dish washing, clothes washing and the like. The intelligent equipment capable of replacing manual labor of people often needs to use large-current devices such as a motor, and the larger the work of the devices is, the larger current is needed, so that the use requirement of the equipment is met, the overlarge power cannot be caused because the current is overlarge, the equipment heats, the equipment is burnt under severe conditions, and the current is needed to be controlled.
In the existing medical equipment, the over-current needs to be detected by using a main control chip, the equipment for detecting the current by using the main control chip has to use an analog-to-digital conversion function to convert a voltage value into a digital value and then judge, the detection device has no self-locking circuit, the over-current state is judged to be released after the power is disconnected, and the switch is opened again, if the over-current state is always in the over-current state, the risk of damage of devices is increased, in addition, the equipment for detecting the over-current by using the main control chip has higher use cost, needs to use a specific port or an analog-to-digital conversion chip, can cause high equipment cost, lacks competitive advantage in market competition of the equipment, and needs more specialized maintenance personnel in later electric maintenance, can cause maintenance difficulty, needs to prepare spare parts in advance, otherwise, has long purchasing period of the spare parts, affects normal operation, causes reputation loss to medical departments, and more importantly delays the diagnosis and treatment of patients,
disclosure of Invention
Aiming at the problems that a specific port or an analog-to-digital conversion chip is needed to control the overcurrent in the existing medical equipment, the equipment cost is high, the competitiveness is reduced and the maintenance is difficult, the invention provides an overcurrent protection circuit of the medical equipment and an overcurrent protection method thereof, which aim to manually adjust the magnitude of protection current according to actual conditions, prevent the overcurrent from passing through by utilizing a self-locking function, prevent devices from being damaged due to frequent switching, reduce the equipment cost and improve the flexibility in the use of the medical equipment.
The technical scheme of the invention is that the overcurrent protection circuit of the medical equipment comprises a sampling resistor, wherein the sampling resistor is connected with an in-phase input end of an amplifying circuit, an output end of the amplifying circuit is connected to a comparison circuit, an output end of the comparison circuit is connected with a first control circuit, a second control circuit is connected to the first control circuit, a fifth transistor is arranged in the first control circuit, a fourth transistor is arranged in the second control circuit, a self-locking circuit is connected between the first control circuit and the second control circuit, the self-locking circuit comprises a first transistor, a second transistor, a voltage dividing circuit and a delay circuit, an analog switch is connected behind the second control circuit, and a third transistor is arranged in the analog switch, and controls the second control circuit and the opening and closing of the analog switch to control whether the load is turned on or not;
further, the voltage dividing circuit in the self-locking circuit comprises a first resistor, a fifth resistor, a second resistor and a fourth resistor, the delay circuit comprises a third resistor and a first capacitor, the voltage dividing circuit provides required voltage for the first transistor and the second transistor, and the delay circuit slows down the rising speed of the base electrode voltage of the first transistor;
further, one end of the sampling resistor is connected with the load and is connected to the amplifying circuit, and the other end of the sampling resistor is grounded;
the amplifying circuit is an in-phase amplifying circuit and comprises a budget amplifier II, a feedback resistor and an adjusting resistor, wherein the feedback resistor is connected between an inverting input end and an output end of the amplifier II, one end of the adjusting resistor is connected to a connection point of the feedback resistor and the inverting input end, and the other end of the adjusting resistor is grounded;
further, the comparison circuit comprises an operational amplifier I and a potentiometer, wherein the non-inverting input end of the operational amplifier I is connected with the output end of the amplification circuit, the inverting input end of the operational amplifier I is connected with the potentiometer, and the output end of the operational amplifier is connected with the base electrode of a fifth transistor in the first control circuit;
further, the first control circuit comprises a resistor eight, the fifth transistor is a triode, wherein the eighth resistor is connected between a base electrode and an emitter electrode of the fifth transistor, the fifth transistor is connected to a base electrode of a fourth transistor in the second control circuit, and the self-locking device is connected between the first control circuit and the second control circuit;
further, the second control circuit comprises a fourth transistor, the fourth transistor is a triode, a reflection electrode of the fourth transistor is grounded, and a collector electrode of the fourth transistor is connected to a seventh resistor at one end of the analog switch;
further, two voltage dividing resistors in the analog switch are a seventh resistor and a sixth resistor, the third transistor is a P-channel field effect transistor, the sixth resistor is connected between the source electrode and the grid electrode of the third transistor, the sixth resistor is connected with the seventh resistor on the grid electrode of the third transistor, and one end of the seventh resistor is grounded.
The over-current protection method for the medical equipment utilizes the over-current protection circuit, obtains the required voltage value through a sampling resistor (R9) in the circuit and an amplifying circuit, then converts the voltage value into high and low levels through a comparison circuit, thereby achieving the effect of controlling a first control circuit, and then controls a second control circuit and a self-locking circuit according to the state of the first control circuit to complete the control of an analog switch and protect the over-current condition.
The invention has the positive effects that: the sampling resistor is arranged in the protection circuit, potential difference is generated when current passes through the sampling resistor to form voltage, the voltage can be sampled to be smaller voltage, the amplifying circuit is arranged to amplify the smaller voltage, the amplifying voltage can prevent interference in the circuit, the comparing circuit is used for judging the difference value between the voltage value of the in-phase input end and the voltage value of the reverse input end and outputting high and low levels, the fifth transistor in the initial state is further turned off in the first control circuit, when the base voltage is high level, the fifth transistor is turned on, the base electrode of the fourth transistor in the second control circuit is connected to the ground, one end of the divider resistor in the analog switch is grounded after the fourth transistor is turned on, the third transistor in the analog switch is turned on, the divider circuit can be used in the self-locking circuit to reduce the voltage to the value capable of meeting the voltage required by the first transistor and the second transistor, the rising speed of the base electrode voltage of the first transistor in the self-locking circuit is slowed down by the delay circuit, the third transistor in the initial state can be turned on in the output high level, the third transistor in the output state is turned on, and the third transistor in the self-locking state is turned on, and the third transistor in the absolute state is turned on; under other conditions, Q3 is disconnected, when the fifth transistor in the first control circuit is turned on, the output end of the self-locking device can be pulled down, the level of the output end of the self-locking device can always keep a low level state, and to release the low level state, the power supply is required to be electrified again or the output end of the self-locking device is placed at a high level, and overcurrent can be prevented from passing through by controlling the closing of the analog switch.
Drawings
Fig. 1 is a control schematic of the present invention.
FIG. 2 is a circuit diagram of the present invention
Description of the reference numerals: c1-first capacitor, PR 1-potentiometer, Q1-first transistor, Q2-second transistor, Q3-third transistor, Q4-fourth transistor, Q5-fifth transistor, R1-first resistor, R2-second resistor, R3-third resistor, R4-fourth resistor, R5-fifth resistor, R6-sixth resistor, R7-seventh resistor, R8-eighth resistor, R9-sampling resistor, RF 1-feedback resistor, RG 1-regulating resistor, U1-first operational amplifier, U2-second operational amplifier, vt-turn-on voltage, VGS-gate-source voltage.
Description of the embodiments
The technical proposal of the invention is an overcurrent protection circuit of medical equipment, and figure 1 is a control schematic diagram of the invention,
In fig. 2, the circuit diagram of the present invention includes a sampling resistor, the sampling resistor R9 is connected to the in-phase input end of the amplifying circuit, the output end of the amplifying circuit is connected to the comparing circuit, the output end of the comparing circuit is connected to the first control circuit, the first control circuit is connected to the second control circuit, the first control circuit is provided with a fifth transistor Q5, the second control circuit is provided with a fourth transistor Q4, a self-locking circuit is connected between the first control circuit and the second control circuit, the self-locking circuit includes a first transistor Q1 and a second transistor Q2, and a voltage dividing circuit and a delay circuit, the second control circuit is connected to an analog switch, the analog switch is provided with a third transistor Q3, and the self-locking circuit controls the second control circuit and the on/off of the analog switch to control whether the load is turned on or not.
The composition is as follows: the self-locking circuit comprises a first transistor Q1, a second transistor Q2, a voltage dividing circuit and a delay circuit, wherein the voltage dividing circuit comprises a fifth resistor R5, a second resistor R2 and a fourth resistor R4, the delay circuit comprises a third resistor R3 and a first capacitor C1, the voltage dividing circuit provides required voltage for the first transistor Q1 and the second transistor Q2, and the delay circuit slows down the rising speed of the voltage of the base electrode of the first transistor Q1;
the function is as follows: the resistor I R1, the resistor IV R4, the resistor II R2 and the resistor V R5 respectively form a voltage dividing circuit, so that the voltage is reduced to the voltage which can be met by the base electrode of the triode; the resistor three R3 and the capacitor one C1 form a delay circuit to slow down the rising speed of the base voltage of the first transistor Q1. The self-locking circuit has the integral function that: in the initial state, the output end NET1 of the self-locking circuit outputs a high level, so that the fourth transistor Q4 is turned on. When Q5 is turned on to pull NET1 low, the level at NET1 will remain low, and no relation to the state of the fifth transistor Q5, and to release the low state, the POWER supply POWER needs to be powered up again or NET1 needs to be set high. In order to prevent the over-current state, the analog switch is continuously switched;
principle of: when the POWER supply POWER is supplied, the voltage dividing circuits are respectively formed by the first resistor R1, the fourth resistor R4, the second resistor R2 and the fifth resistor R5 to supply POWER to the bases of the first transistor Q1 and the second transistor Q2, and the second transistor Q2 is preferentially conducted due to the delay circuit formed by the third resistor R3 and the first capacitor C1, so that after the second transistor Q2 is conducted, the base of the first transistor Q1 is connected to the ground through the ground resistor R3, so that the first transistor Q1 is not conducted, and at this time, the voltage at the output end NET1 of the self-locking circuit is consistent with the base voltage of the second transistor Q2, so that the fourth transistor Q4 is conducted. When the fifth transistor Q5 is turned on and the output NET1 of the self-locking circuit is connected to the ground, the second transistor Q2 is turned off, while the base of the first transistor Q1 is in a high level state, the first transistor Q1 is turned on, the output NET1 of the self-locking circuit is kept in a low level state, which is not related to the state of the fifth transistor Q5, and if the high level state needs to be recovered, the POWER supply POWER needs to be turned on from a new state or the output NET1 of the self-locking circuit is set to a high level.
The composition is as follows: the sampling resistor R9 is connected with the load and the amplifier at the same time, and the other end of the sampling resistor R9 is grounded;
the function is as follows: when current flows through the sampling resistor R9, a potential difference is generated to form voltage;
principle of: the noninverting input end of the operational amplifier U2 is connected to the sampling resistor R9, when current flows through the sampling resistor R9, a potential difference is generated, and the noninverting input end of the operational amplifier U2 samples voltage.
The composition is as follows: the amplifying circuit is an in-phase amplifying circuit, and comprises a budget amplifier II U2, a feedback resistor RF1 and an adjusting resistor RG1, wherein the feedback resistor RF1 is connected between the inverting input end and the output end of the amplifier II U2, one end of the adjusting resistor RG1 is connected to the connection point of the feedback resistor RF1 and the inverting input end, and the other end of the adjusting resistor RG1 is grounded;
the function is as follows: the smaller the sampling resistance is, the better the value is, so that the ohm's law is adopted: the voltage is equal to the current multiplied by the resistor U=IR, and the voltage value of the U2 in-phase input end can be judged to be very small and is easy to interfere, so that the voltage value needs to be amplified by an in-phase amplifying circuit for subsequent use;
principle of: and the operational amplifier II U2, the feedback resistor and the regulating resistor RG1 form an in-phase amplifying circuit, the sampled small voltage signal is amplified into a large voltage signal, and the output voltage is equal to 1 plus RF1 divided by RG1 and multiplied by the input voltage Vout= (1+ (RF 1/RG 1)) ×vin.
The composition is as follows: an operational amplifier U1 and a potentiometer PR1;
the function is as follows: the difference value between the voltage value of the non-inverting input end and the voltage value of the inverting input end is judged, and the high level and the low level are output;
principle of: in the open loop state of the operational amplifier U1, a voltage comparator is formed, and according to the characteristics of the operational amplifier U1, the voltage value of the non-inverting input end and the voltage value of the inverting input end are differed, and when the difference is larger than 0, the voltage value which is infinitely close to a positive power rail and the power supply voltage VCC are output; when the voltage value is smaller than 0, the voltage value of the output infinitely close to the negative power rail is grounded GND. The potentiometer acts as two resistor voltage divider to provide a reference voltage for the inverting input end, and the reference voltage of the inverting input end can be adjusted by adjusting the position of the potentiometer;
the comparison circuit comprises an operational amplifier U1 and a potentiometer PR1, wherein the non-inverting input end of the operational amplifier U1 is connected with the output end of the amplifying circuit, the inverting input end of the operational amplifier U1 is connected with the potentiometer, and the output end of the operational amplifier U1 is connected with the base electrode of a fifth transistor Q5 in the first control circuit.
The composition is as follows: an eighth resistor R8, a fifth transistor Q5 (triode); the first control circuit comprises an eighth resistor R8 and a fifth transistor Q5, the fifth transistor Q5 is a triode, the eighth resistor R8 is connected between the base electrode and the emitter electrode of the fifth transistor Q5, the fifth transistor Q5 is connected to the base electrode of a fourth transistor Q4 in the second control circuit, and the self-locking device is connected between the base electrode and the emitter electrode;
the function is as follows: the fifth transistor Q5 is turned off in the initial state, and when the base voltage is at a high level, the fifth transistor Q5 is turned on to connect the base of the fourth transistor Q4 to the ground;
principle of: when the base voltage is at a high level, the fifth transistor Q5 is turned on; when the base voltage is at a low level, the fifth transistor Q5 is turned off. One end of the eighth resistor R8 is grounded, and the other end of the eighth resistor R8 is connected with the base electrode of the fifth transistor Q5, so that the fifth transistor Q5 defaults to be in an off state.
The composition is as follows: a fourth transistor Q4 (triode); the second control circuit comprises a fourth transistor Q4, the reflecting electrode of the fourth transistor Q4 is grounded, the collector electrode of the fourth transistor Q4 is connected to a seventh resistor R7 at one end of the analog switch, and one end of the seventh resistor R7 is grounded;
the function is as follows: after being conducted, one end of the seventh resistor R7 is grounded, so that the third transistor Q3 is conducted;
principle of: when the base voltage is at a high level, the fourth transistor Q4 is turned on; when the base voltage is low, the fourth transistor Q4 is turned off.
The composition is as follows: a sixth resistor R6, a seventh resistor R7, and a third transistor Q3 (P-channel field effect transistor PMOS); the analog switch comprises a third transistor Q3 and two voltage dividing resistors in two voltage dividing circuits, wherein the two voltage dividing resistors are a seventh resistor R6 and a sixth resistor R6, the third transistor is a P-channel field effect transistor PMOS, the sixth resistor R6 is connected between the source electrode and the grid electrode of the third transistor Q3, the sixth resistor R6 is connected with the seventh resistor R7 in series on the grid electrode of the third transistor Q3;
the function is as follows: when the fourth transistor Q4 is turned on, the sixth resistor R6 and the seventh resistor R7 form a voltage dividing circuit, so that the absolute value (|vgs|) of the gate-source voltage is greater than the turn-on voltage Vt, and the third transistor Q3 is turned on; in other cases, the third transistor Q3 is turned off;
principle of: the P-channel field effect transistor PMOS is turned on when the absolute value (|VGS|) of the gate-source voltage is larger than the on voltage Vt, and is turned off otherwise. The fourth transistor R6 plays a role in pulling up the grid electrode of the P-channel field effect transistor PMOS when the Q4 is not conducted; when Q4 is conducted, the sixth resistor R6 and the seventh resistor R7 form a voltage dividing circuit, so that the conducting condition is met under the condition that the grid-source voltage |VGS of the field effect transistor does not exceed the limit parameter of the PMOS.
The whole circuit principle is as follows:
when the POWER supply is input, the self-locking circuit works at first, the first resistor R1, the fourth resistor R4, the second resistor R2 and the fifth resistor R5 respectively form a voltage dividing circuit to respectively supply POWER to the bases of the first transistor Q1 (triode) and the second transistor Q2 (triode), and the third resistor R3 and the first capacitor C1 form a delay circuit to lead the second transistor Q2 to be preferentially conducted, so that after the second transistor Q2 is conducted, the base of the first transistor Q1 is connected to the ground through the third resistor R3, and the first transistor Q1 is not conducted, at the moment, the voltage at the output end NET1 of the self-locking circuit is consistent with the base voltage of the second transistor Q2, so that the fourth transistor Q4 is conducted, the third transistor Q3 is conducted to supply POWER to the load normally, and meanwhile, the voltage is generated at the sampling resistor R9 and is input to the input end of the second operational amplifier U2, amplified through the second operational amplifier U2, and output to the input end of the first operational amplifier U1 in phase, and the output voltage is compared with the high-level voltage and low-level voltage input end.
Taking the figure as an example, assuming that the voltage of the inverting input terminal of the operational amplifier U1 is 1V, the output rail of the operational amplifier is rail-to-rail; the amplifying circuit is amplified by 20 times; the sampling resistor is 100mΩ; calculation shows that the circuit is cut off when the current is greater than 5A.
When the operating current is less than 5A (4A is an example), the voltage at the non-inverting input terminal of the operational amplifier U2 is equal to 4A multiplied by 10mΩ to be equal to 40mV, by amplifying by 20 times, the voltage at the output terminal of U2 is equal to 800mV, the voltage at the non-inverting input terminal of U1 is 800mV minus the voltage at the inverting input terminal of 1V to be equal to minus 200mV, so the voltage at the output terminal of U1 is equal to the negative power rail voltage, and GND. At this time, the base of the fifth transistor Q5 is at a low level, the fifth transistor Q5 is not turned on, the base of the fourth transistor Q4 is still at a high level, and the circuit normally supplies power to the load.
Example two
When the operating current is greater than 5A (taking 6A as an example), the U2 in-phase input voltage is equal to 6A multiplied by 10mΩ and is equal to 60mV, by amplifying by 20 times, the U2 output voltage is equal to 1200mV, the U1 in-phase input voltage 1200mV minus the inverting input voltage 1V is equal to 200mV, so the U1 output voltage is equal to the positive supply rail voltage, and VCC. At this time, the base of Q5 is at high level, Q5 is on, the base of Q4 will be pulled low, and Q3 will be off. The voltage at NET1 is pulled down, the base of Q2 is low, Q2 is off, the base of Q1 is in high state, Q1 is on, NET1 is kept in low state, and the state of Q5 is irrelevant. If POWER is not powered up again or NET1 is set high, the load will always be in a powered down state.
When overcurrent is detected, the Q3 is turned off, no voltage is generated at the R9 position because no current flows, but weak voltage exists due to the characteristic of the device, and output cannot be influenced, so that the U1 output end inevitably outputs low level. This is that Q5 will be off and the Q4 base voltage will be controlled by NET1, with NET1 low.
The over-current protection method for the medical equipment utilizes the over-current protection circuit, obtains the required voltage value through the sampling resistor R9 in the circuit and the amplifying circuit, then converts the voltage value into high and low levels through the comparison circuit, thereby achieving the effect of controlling the first control circuit, and then controls the second control circuit and the self-locking circuit according to the state of the first control circuit, thereby completing the control of the analog switch and protecting the over-current condition.
Although the present embodiment is used in the field of medical equipment, the present circuit can be used to realize overcurrent protection in the field of general electrical equipment.
The local positive effects of the invention are: by utilizing the oversampling R9, potential difference is generated when current in the protection circuit flows through the sampling resistor R9, so that voltage is formed, and the voltage can be sampled to be smaller; by using an amplifying circuit, a smaller voltage can be amplified, and the amplified voltage can be prevented from being disturbed in the circuit; by arranging the comparison circuit, the voltage can judge the difference value between the voltage value of the non-inverting input end and the voltage value of the inverting input end in the comparison circuit, and the high-low level is output; by setting the first control circuit, in the first control circuit, the fifth transistor Q5 in the initial state is cut off, when the base voltage is high level, the fifth transistor Q5 is conducted, the base electrode of the fourth transistor Q4 in the second control circuit is connected to the ground, and after the base electrode is conducted, one end of the voltage dividing resistor in the analog switch is grounded, so that the third transistor Q3 in the analog switch is conducted; the voltage can be reduced to the voltage required by the bases of the first transistor Q1 and the second transistor Q2 by utilizing a voltage dividing circuit in the self-locking circuit arranged between the first control circuit and the second control circuit, the rising speed of the base voltage of the first transistor Q1) in the self-locking circuit is slowed down by utilizing a delay circuit, the output end of the self-locking device can output high level in an initial state, the fourth transistor Q4 in the second control circuit is conducted, the voltage dividing circuit is formed in the self-locking device, the absolute value |VGS| of the gate-source voltage of the third transistor Q3 is larger than the conducting voltage Vt, and the third transistor Q3 is further conducted; under other conditions, when the Q3 is disconnected and the fifth transistor Q5 in the first control circuit is turned on, the output end of the self-locking device can be pulled down, the level of the output end of the self-locking device can always keep a low level state, and when the low level state is released, the power supply is required to be electrified again or the output end of the self-locking device is placed at a high level, and the over-current can be prevented from passing through by controlling the closing of the analog switch; the invention can manually adjust the magnitude of the protection current according to the actual situation, prevents the over-current from passing through by utilizing the self-locking function, prevents devices from being damaged due to frequent switching, reduces the equipment cost and improves the flexibility in the use of medical equipment.
Claims (9)
1. An overcurrent protection circuit for a medical device, characterized by: the current protection circuit comprises a sampling resistor, the sampling resistor (R9) is connected with the in-phase input end of the amplifying circuit, the output end of the amplifying circuit is connected to the comparing circuit, the output end of the comparing circuit is connected with the first control circuit, the first control circuit is connected with the second control circuit, the first control circuit is provided with a fifth transistor (Q5), the second control circuit is provided with a fourth transistor (Q4), a self-locking circuit is connected between the first control circuit and the second control circuit, the self-locking circuit comprises a first transistor (Q1), a second transistor (Q2), a voltage dividing circuit and a time delay circuit, the second control circuit is connected with an analog switch, the analog switch is provided with a third transistor (Q3), and the self-locking circuit controls the second control circuit and the on/off of the analog switch so as to control whether the load is conducted or not.
2. The overcurrent protection circuit of a medical device of claim 1, wherein: the voltage dividing circuit in the self-locking circuit comprises a first resistor (R1), a fifth resistor (R5), a second resistor (R2) and a fourth resistor (R4), the delay circuit comprises a third resistor (R3) and a first capacitor (C1), the voltage dividing circuit provides required voltage for the first transistor (Q1) and the second transistor (Q2), and the delay circuit slows down the rising speed of the base voltage of the first transistor (Q1).
3. The overcurrent protection circuit of a medical device of claim 1, wherein: one end of the sampling resistor (R9) is connected with the load and is connected to the amplifying circuit, and the other end of the sampling resistor is grounded.
4. The overcurrent protection circuit of a medical device of claim 1, wherein: the amplifying circuit is an in-phase amplifying circuit, and comprises a budget amplifier II (U2), a feedback resistor (RF 1) and an adjusting resistor (RG 1), wherein the feedback resistor (RF 1) is connected between the inverting input end and the output end of the amplifier II (U2), one end of the adjusting resistor (RG 1) is connected to the connection point of the feedback resistor (RF 1) and the inverting input end, and the other end of the adjusting resistor (RG 1) is grounded.
5. The overcurrent protection circuit of a medical device of claim 1, wherein: the comparison circuit comprises an operational amplifier I (U1) and a potentiometer (PR 1), wherein the non-inverting input end of the operational amplifier I (U1) is connected with the output end of the amplification circuit, the inverting input end of the operational amplifier I (U1) is connected with the potentiometer, and the output end of the operational amplifier I (U1) is connected with the base electrode of a fifth transistor (Q5) in the first control circuit.
6. The overcurrent protection circuit of a medical device of claim 1, wherein: the first control circuit comprises an eighth resistor (R8), the fifth transistor (Q5) is a triode, the eighth resistor (R8) is connected between the base electrode and the emitter electrode of the fifth transistor (Q5), the fifth transistor (Q5) is connected to the base electrode of the fourth transistor (Q4) in the second control circuit, and the self-locking device is connected between the first control circuit and the second control circuit.
7. The overcurrent protection circuit of a medical device of claim 1, wherein: the fourth transistor (Q4) in the second control circuit is a triode, the reflecting electrode of the fourth transistor (Q4) is grounded, and the collector electrode of the fourth transistor (Q4) is connected to a seventh resistor (R7) at one end of the analog switch.
8. The overcurrent protection circuit of a medical device of claim 1, wherein: two divider resistors in the analog switch are a seventh resistor (R7) and a sixth resistor (R6), the third transistor is a P-channel field effect transistor (PMOS), the sixth resistor (R6) is connected between the source electrode and the grid electrode of the third transistor (Q3), the sixth resistor (R6) is connected with the seventh resistor (R7) on the grid electrode of the third transistor (Q3), and one end of the seventh resistor (R7) is grounded.
9. A method of overcurrent protection for a medical device using a circuit as claimed in any one of claims 1 to 9, characterized in that: the sampling resistor (R9) in the circuit is used for obtaining the required voltage value, the voltage value is converted into high and low level through the comparison circuit, so that the effect of controlling the first control circuit is achieved, the second control circuit and the self-locking circuit are controlled according to the state of the first control circuit, the control of the analog switch is completed, and the overcurrent condition is protected.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310732037.2A CN116799743A (en) | 2023-06-19 | 2023-06-19 | Overcurrent protection circuit of medical equipment and overcurrent protection method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310732037.2A CN116799743A (en) | 2023-06-19 | 2023-06-19 | Overcurrent protection circuit of medical equipment and overcurrent protection method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116799743A true CN116799743A (en) | 2023-09-22 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310732037.2A Pending CN116799743A (en) | 2023-06-19 | 2023-06-19 | Overcurrent protection circuit of medical equipment and overcurrent protection method thereof |
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| CN (1) | CN116799743A (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106451341A (en) * | 2016-11-22 | 2017-02-22 | 亿嘉和科技股份有限公司 | Load overcurrent protection circuit and load overcurrent protection method |
| CN107093883A (en) * | 2017-06-27 | 2017-08-25 | 青岛鲁渝能源科技有限公司 | Protection circuit, radio energy transmission system and excessively stream/short-circuit protection method |
| US20190199087A1 (en) * | 2017-12-22 | 2019-06-27 | Autochips Inc. | Short-circuit protection apparatus and method |
| CN213693129U (en) * | 2020-09-04 | 2021-07-13 | 柏宜照明（上海）股份有限公司 | Overcurrent protection circuit |
| CN113241724A (en) * | 2021-04-25 | 2021-08-10 | 上海空间电源研究所 | Load power supply overcurrent self-locking and unlocking circuit and method for satellite |
| CN216794614U (en) * | 2022-02-11 | 2022-06-21 | 深圳摩吉智行科技有限公司 | MOS manages overcurrent protection's self-lock device and self-lock protection circuit |
-
2023
- 2023-06-19 CN CN202310732037.2A patent/CN116799743A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106451341A (en) * | 2016-11-22 | 2017-02-22 | 亿嘉和科技股份有限公司 | Load overcurrent protection circuit and load overcurrent protection method |
| CN107093883A (en) * | 2017-06-27 | 2017-08-25 | 青岛鲁渝能源科技有限公司 | Protection circuit, radio energy transmission system and excessively stream/short-circuit protection method |
| US20190199087A1 (en) * | 2017-12-22 | 2019-06-27 | Autochips Inc. | Short-circuit protection apparatus and method |
| CN213693129U (en) * | 2020-09-04 | 2021-07-13 | 柏宜照明（上海）股份有限公司 | Overcurrent protection circuit |
| CN113241724A (en) * | 2021-04-25 | 2021-08-10 | 上海空间电源研究所 | Load power supply overcurrent self-locking and unlocking circuit and method for satellite |
| CN216794614U (en) * | 2022-02-11 | 2022-06-21 | 深圳摩吉智行科技有限公司 | MOS manages overcurrent protection's self-lock device and self-lock protection circuit |
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