CN215681904U - Power supply switching circuit and medical equipment - Google Patents
Power supply switching circuit and medical equipment Download PDFInfo
- Publication number
- CN215681904U CN215681904U CN202120852960.6U CN202120852960U CN215681904U CN 215681904 U CN215681904 U CN 215681904U CN 202120852960 U CN202120852960 U CN 202120852960U CN 215681904 U CN215681904 U CN 215681904U
- Authority
- CN
- China
- Prior art keywords
- power supply
- circuit
- control circuit
- power
- switch
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000001514 detection method Methods 0.000 claims abstract description 14
- 239000000126 substance Substances 0.000 claims description 6
- 230000005611 electricity Effects 0.000 claims description 2
- 239000003990 capacitor Substances 0.000 description 10
- 238000000034 method Methods 0.000 description 3
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 2
- 230000003111 delayed effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 229910052744 lithium Inorganic materials 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008094 contradictory effect Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003071 parasitic effect Effects 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 230000001960 triggered effect Effects 0.000 description 1
Images
Landscapes
- Direct Current Feeding And Distribution (AREA)
Abstract
The utility model discloses a power supply switching circuit and medical equipment, wherein the power supply switching circuit comprises: the power supply comprises a first power supply access end, a second power supply access end, a first switch control circuit and a second switch control circuit; the detection end and the input end of the first switch control circuit are both connected with the first power supply access end, and the output end of the first switch control circuit is connected with the power load; the input end of the second switch control circuit is connected with the second power supply access end, the detection end of the second switch control circuit is connected with the first power supply access end, and the output end of the second switch control circuit is connected with the power load; when the first power supply is powered on, the first switch control circuit controls the first power supply to output the first power supply to the power utilization load, and when the first power supply is powered off, the second switch control circuit controls the second power supply to output the second power supply to the power utilization load.
Description
Technical Field
The utility model relates to the technical field of electronic power, in particular to a power supply switching circuit and medical equipment.
Background
The existing electric equipment generally outputs a direct current power supply for supplying power after the commercial power is processed by a switching power supply, but in actual use, the problem of commercial power outage is difficult to avoid. This can result in the device losing its power supply and becoming inoperable.
SUMMERY OF THE UTILITY MODEL
The utility model mainly aims to provide a power supply switching circuit, aiming at preventing the problem that equipment cannot work due to mains supply outage.
To achieve the above object, the present invention provides a power switching circuit, including:
the first power supply access end is used for accessing a first power supply;
the second power supply access end is used for accessing a second power supply;
the detection end and the input end of the first switch control circuit are both connected with the first power supply access end, and the output end of the first switch control circuit is connected with an electricity load;
the input end of the second switch control circuit is connected with the second power supply access end, the detection end of the second switch control circuit is connected with the first power supply access end, and the output end of the second switch control circuit is connected with the electric load; wherein the content of the first and second substances,
the first switch control circuit is used for controlling the first power supply to output a first power supply to an electric load when the first power supply access end is detected to be connected to the first power supply; and the second switch control circuit is used for controlling the second power supply to output a second power supply to the electric load when detecting that the first power supply access end is not accessed to the first power supply.
Optionally, the second switch control circuit is further configured to control the second power supply to stop outputting the second power supply to the electrical load when it is detected that the first power supply input is resumed at the first power supply input end after the second power supply is controlled to output the second power supply to the electrical load.
Optionally, the first switch control circuit comprises:
the input end of the first switch circuit is connected with the first power supply access end, and the output end of the first switch circuit is connected with the power utilization load;
the detection end of the first control circuit is connected with the first power supply access end, the output end of the first control circuit is connected with the controlled end of the first switch circuit, and the first control circuit is used for controlling the first switch circuit to be turned on when the first power supply access end is detected to be connected into the first power supply.
Optionally, the first switching circuit comprises:
the first switch tube and the second switch tube; wherein the content of the first and second substances,
the input end of the first switch tube is connected with the input end of the second switch tube, the output end of the first switch tube is connected with the first power supply access end, and the output end of the second switch tube is connected with the power load.
Optionally, the first control circuit comprises:
the input end of the first voltage division circuit is connected with the first power supply access end, and the first voltage division circuit divides the voltage of the first power supply and outputs the divided voltage;
and the input end of the third switching tube is grounded, the output end of the third switching tube is connected with the controlled end of the first switching circuit, and the controlled end of the third switching tube is connected with the output end of the first voltage division circuit.
Optionally, the first control circuit further comprises:
and the input end of the delay circuit is connected with the output end of the first voltage division circuit, the output end of the delay circuit is connected with the controlled end of the second switch circuit, and the delay circuit is used for outputting the first power supply access signal after delaying.
Optionally, the second switch control circuit comprises:
the input end of the second switch circuit is connected with the second power supply access end, and the output end of the second switch circuit is connected with an electric load;
and the detection end of the second control circuit is connected with the first power supply access end, the output end of the first control circuit is connected with the controlled end of the second switch circuit, and the second control circuit is used for controlling the second switch circuit to be switched on when the first power supply access end is not connected into the first power supply.
Optionally, the second switch control circuit further comprises:
and the anode of the diode is connected with the input end of the second switching circuit, and the cathode of the diode is connected with the output end of the second switching circuit.
Optionally, the second control circuit comprises:
the input end of the second voltage division circuit is connected with the first power supply access end, and the second voltage division circuit divides the voltage of the first power supply and outputs the divided voltage;
the input end of the inverting circuit is connected with the output end of the second voltage division circuit, and the inverting circuit is used for inverting and outputting the divided first power supply;
and the controlled end of the fourth switching tube is connected with the output end of the inverter circuit, the input end of the fourth switching tube is grounded, and the output end of the fourth switching tube is connected with the controlled end of the second switching circuit.
The utility model also provides medical equipment, which comprises a first power supply, a second power supply, an electric load and the power supply switching circuit;
a first power supply access end of the power supply switching circuit is connected to the first power supply; and a second power supply access end of the power supply switching circuit is connected to the second power supply, and a power supply output end of the power supply switching circuit is connected with the power load.
The technical scheme of the utility model simultaneously detects the power-on/power-off of a first power supply by arranging a first switch control circuit and a second switch control circuit; when the first power supply is detected to be electrified, the first switch control circuit controls the input end and the output end of the first switch control circuit to be conducted, so that the first power supply is controlled to output the first power supply to the power load; when the first power supply is detected to be powered off, the second switch control circuit controls the input end and the output end of the second switch control circuit to be conducted, and controls the second power supply to output the second power supply to the power utilization load; therefore, whether the first power supply is powered off or not, the power load has power input, so that the situation that the power load cannot work due to the fact that the first power supply is powered off can be avoided, and the reliability of the electric equipment is improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.
FIG. 1 is a circuit diagram of a power switching circuit according to an embodiment of the present invention;
fig. 2 is a circuit diagram of another embodiment of the power switching circuit of the present invention.
The reference numbers illustrate:
| reference numerals | Name (R) | Reference numerals | Name (R) |
| 10 | First of allSwitch control circuit | R1～R13 | First to |
| 20 | Second switch control circuit | Q1～Q4 | First to fourth switching tubes |
| 30 | First power supply access terminal | C1、C2 | First and |
| 40 | Second power supply access terminal | D1 | Diode with a high-voltage source |
The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.
In the present invention, unless otherwise expressly stated or limited, the terms "connected," "secured," and the like are to be construed broadly, and for example, "secured" may be a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In addition, the descriptions related to "first", "second", etc. in the present invention are only for descriptive purposes and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.
The utility model provides a power supply switching circuit, which can be used for various electric equipment, such as medical electronic equipment.
In an embodiment of the present invention, the power switching circuit includes:
a first power supply access terminal 30 for accessing a first power supply;
a second power supply access terminal 40 for accessing a second power supply;
the detection end and the input end of the first switch control circuit 10 are both connected with the first power supply access end 30, and the output end of the first switch control circuit 10 is connected with an electric load;
an input end of the second switch control circuit 20 is connected to the second power supply input end 40, a detection end of the second switch control circuit 20 is connected to the first power supply input end 30, and an output end of the second switch control circuit 20 is connected to the power load; wherein the content of the first and second substances,
the first switch control circuit 10 is configured to control the first power supply to output the first power supply to the electrical load when detecting that the first power supply access terminal 30 is connected to the first power supply; the second switch control circuit 20 is configured to control the second power supply to output a second power supply to the electrical load when detecting that the first power supply access terminal 30 does not access the first power supply.
In this embodiment, the first power supply input end 30 can be connected to the mains supply, and in practical application, a power supply circuit is further included between the first power supply input end 30 and the mains supply, so that the mains supply can be converted into a direct current power supply meeting the requirement of the power load. The second power input terminal 40 can be connected to a backup power source, such as a lithium battery. Of course, in other embodiments, the first power input terminal 30 and the second power input terminal 40 may also be connected to other types of power sources, such as a generator, and the like, which is not limited herein.
The first switch control circuit 10 and the second switch control circuit 20 may determine whether the first power supply is connected to the first power supply at the first power supply connection end 30 by detecting a voltage of the first power supply connection end 30, that is, determine whether the first power supply is powered on or powered off, for example, when the voltage of the first power supply connection end 30 is detected to be greater than a preset voltage, determine that the first power supply is powered on, and when the voltage of the first power supply end is detected to be less than the preset voltage, determine that the first power supply is powered off.
The first switch control circuit 10 and the second switch control circuit 20 can control the on/off between the input terminal and the output terminal of the first switch control circuit according to whether the first power supply is connected to the first power supply access terminal 30, and further control whether the first power supply and the second power supply are output to the power load. In this embodiment, the control logic of the first switch control circuit 10 may be opposite to the control logic of the second switch control circuit 20, that is, when the first switch control circuit 10 is turned on, the second switch control circuit 20 is in an off state, and conversely, when the first switch control circuit 10 is in an off state, the second switch control circuit 20 is in an on state. For example, when detecting that the first power supply is powered on, the first switch control circuit 10 may control the first power supply connection end 30 to be electrically connected to the electrical load, so as to control the first power supply to be output to the electrical load, and at this time, the second switch control circuit 20 may be in an off state, so as to prevent the first power supply from flowing backward to the second power supply; similarly, when detecting that the first power supply is not connected or the first power supply is powered down, the second switch control circuit 20 may control the second power supply connection end 40 to be electrically connected with the electrical load, so as to control the second power supply to be output to the electrical load, and at this time, the first switch control circuit 10 may be in a disconnected state, so as to prevent the second power supply from flowing backward to the first power supply. So, when inserting first power and second power simultaneously, power supply switching circuit exports first power, also the commercial power to power consumption load in the priority, and remains the electric energy of second power, also remains the electric energy of lithium cell, as stand-by power supply to use when the commercial power falls, thereby improve consumer's duration.
The technical scheme of the utility model is that a first switch control circuit 10 and a second switch control circuit 20 are arranged to simultaneously detect the power-on/power-off of a first power supply; when the first power supply is detected to be electrified, the first switch control circuit 10 controls the input end and the output end of the first switch control circuit to be conducted, so that the first power supply is controlled to output the first power supply to the power load; when the first power supply is detected to be powered off, the second switch control circuit 20 controls the input end and the output end of the second switch control circuit to be conducted, and controls the second power supply to output the second power supply to the power load; therefore, whether the first power supply is powered off or not, the power load has power input, so that the situation that the power load cannot work due to the fact that the first power supply is powered off can be avoided, and the reliability of the electric equipment is improved.
In an embodiment, the second switch control circuit 20 is further configured to control the second power supply to stop outputting the second power supply to the electrical load when it is detected that the first power supply input is resumed at the first power supply input end 30 after controlling the second power supply to output the second power supply to the electrical load.
In this embodiment, when the first power supply access terminal 30 recovers to access the first power supply, that is, when the first power supply is powered on again, the first switch control circuit 10 is switched from the off state to the on state, so as to output the first power supply to the power load; the second switch control circuit 20 is switched from the on state to the off state, so as to control the second power supply to stop outputting the second power supply to the electrical load. The first power supply and the second power supply can be prevented from being simultaneously switched on to the power utilization load, the output current is larger than the current of the power utilization load, the power utilization load is caused to be damaged due to overcurrent, meanwhile, the first power supply with higher output voltage can be prevented from flowing backwards to the second power supply with lower output voltage through the second switch control circuit 20, the second power supply is damaged, and meanwhile, when the first power supply and the second power supply are both powered on, the first power supply is preferentially used, and the electric energy of the second power supply is reserved.
In one embodiment, the first switch control circuit 10 includes:
the input end of the first switch circuit is connected with the first power supply access end 30, and the output end of the first switch circuit is connected with the power load;
and the detection end of the first control circuit is connected with the first power supply access end 30, the output end of the first control circuit is connected with the controlled end of the first switch circuit, and the first control circuit is used for controlling the first switch circuit to be turned on when the first power supply access end 30 is detected to be connected into the first power supply. And when the first power supply is detected to be powered down, controlling the first switching circuit to be cut off.
In this embodiment, the first switch circuit may be turned on at a high level and turned off at a low level, or the first switch circuit may be turned on at a low level and turned off at a high level; the method is specifically set according to actual requirements.
The first control circuit may determine that the first power supply is powered off/powered on according to a relationship between a voltage of the first power supply and a preset voltage, for example, when it is detected that the voltage of the first power supply is greater than the preset voltage, it is determined that the first power supply is powered on, and when the voltage of the first power supply is less than the preset voltage, it is determined that the first power supply is powered off, and a corresponding control signal is output to control the first switching circuit to be turned on/off.
In this embodiment, when the first power supply is powered on, the first control circuit controls the first switch circuit to be turned on, so that the first power supply is output to the power load to supply power to the power load, and when the first power supply is powered off, the first switch circuit is controlled to be turned off, thereby preventing signals on the power load side, such as a second power supply from damaging the first power supply.
In one embodiment, the first switching circuit includes:
a first switch tube Q1 and a second switch tube Q2; wherein the content of the first and second substances,
an input end of the first switch tube Q1 is connected to an input end of the second switch tube Q2, an output end of the first switch tube Q1 is connected to the first power supply input end 30, and an output end of the second switch tube Q2 is connected to the power load.
The first switch Q1 and the second switch Q2 may be MOS transistors or other switching devices having a body diode D1, and are specifically configured according to actual requirements, and are not limited herein. The cathodes of the two body diodes D1 are interconnected to make the anode between the two diodes D1 non-conductive, thereby preventing the current from flowing backward.
In this embodiment, a first switch transistor Q1 and a second switch transistor Q2 are taken as PMOS transistors as an example, a first switch transistor Q1 is marked as a first PMOS transistor, and a second switch transistor Q2 is marked as a second PMOS transistor as an example, wherein an anode of a body diode D1 of the PMOS transistor is a drain of the PMOS transistor; the cathode of the PMOS body diode D1 is the source electrode of the PMOS tube; the source electrode of the first PMOS tube is connected with the source electrode of the second PMOS tube, the drain electrode of the first PMOS tube is connected to a first power supply, and the drain electrode of the second PMOS tube is connected with the power load; the grid electrode of the first PMOS tube is connected with the grid electrode of the second PMOS tube;
in this embodiment, the on/off of the first PMOS and the second PMOS is controlled by the first control circuit according to whether the first power supply is connected. When the first power supply is powered down, the first control circuit controls the first PMOS and the second PMOS to be cut off, and at the moment, at least one of the body diodes D1 of the first PMOS and the second PMOS is in a cut-off state, so that the second power supply or other power supplies are prevented from flowing backwards to the first power supply, and the first power supply is prevented from being damaged. When the first power supply is powered on, the first control circuit controls the first PMOS and the second PMOS to be started, at the moment, the conduction voltage drop of the first PMOS and the second PMOS is very low, and compared with the traditional method that the reverse flow is prevented through the diode D1 (for a large-current power supply, the current is as high as 5-10A, and according to a calculation formula of the power, the power is equal to the current multiplied by the voltage, and the energy loss caused by the diode D1 with large conduction voltage drop is very large), the conduction voltage drop of the first PMOS and the second PMOS in the embodiment is very low, so that the energy loss generated by the first PMOS tube and the second PMOS tube is very low.
Furthermore, the first switch circuit further comprises a first resistor R1, one end of the first resistor R1 is connected with a common end of the source electrode of the first PMOS transistor and the source electrode of the second PMOS transistor, the other end of the first resistor R1 is connected with a common end of the gate electrode of the first PMOS transistor and the gate electrode of the second PMOS transistor, and the first resistor R1 is used for discharging the voltage of the parasitic capacitors of the first PMOS transistor and the second PMOS transistor, so that the service life and the stability of the PMOS transistors are improved.
In one embodiment, the first control circuit includes:
a first voltage dividing circuit, an input end of which is connected to the first power supply input end 30, wherein the first voltage dividing circuit divides the voltage of the first power supply and outputs the divided voltage;
and an input end of the third switching tube Q3 is grounded, an output end of the third switching tube Q3 is connected with a controlled end of the first switching circuit, and a controlled end of the third switching tube Q3 is connected with an output end of the first voltage division circuit.
In this embodiment, the first voltage dividing circuit includes a second resistor R2 and a third resistor R3, one end of the second resistor R2 is connected to the first power supply, the other end of the second resistor R2 is connected to one end of the third resistor R3, and the other end of the third resistor R3 is grounded. The common end of the second resistor R2 and the third resistor R3 is the output end of the first voltage division circuit, and the first voltage division circuit reduces the first power supply into a voltage signal which can be received by the third switch tube Q3 and then outputs the voltage signal according to the resistance ratio of the first resistor R1 and the second resistor R2. Of course, in other embodiments, the first voltage dividing circuit may also be a voltage dropping chip such as an LDO. In this embodiment, the first power supply voltage signal is a high level signal.
The third switching tube Q3 may be one or more of a triode, a MOS tube, or an IGBT. The third switch tube Q3 may be turned on when receiving a high level signal and turned off when receiving a low level signal, the first control circuit further includes a fourth resistor R4, one end of the fourth resistor R4 is connected to the controlled end of the third switch tube Q3, and the other end of the fourth resistor R4 is grounded.
In this embodiment, the first switch circuit is turned on when the controlled terminal is in a low level state, and turned off when the controlled terminal is in a high level state.
When the first power supply is switched on, the first sampling circuit divides the first power supply into voltage signals which can be accepted by the third switching tube Q3, namely high-level signals are output to the third switching tube Q3, so that the third switching tube Q3 is turned on, the level of the controlled end of the first switching circuit is pulled down, the controlled end of the first switching circuit is in a low-level state, the first switching circuit is controlled to be turned on, and the first power supply is output to the power load; when the first power supply is powered off, the first voltage division circuit does not output, the fourth resistor R4 pulls down the level of the controlled terminal of the third switching tube Q3, so that the third switching tube Q3 is turned off, and the level of the controlled terminal of the first switching circuit is clamped in a high level state, that is, a high level signal is output to the first switching circuit to control the first switching circuit to be turned off.
In some embodiments, the first control circuit further includes a fifth resistor R5, and the fifth resistor R5 is connected in series between the input terminal of the third switching transistor Q3 and the first switching circuit, in this embodiment, by adjusting the resistance of the fifth resistor R5, the voltage value of the controlled terminal of the first switching circuit when clamped can be adjusted.
In one embodiment, the first control circuit further comprises:
and the input end of the delay circuit is connected with the output end of the first voltage division circuit, the output end of the delay circuit is connected with the controlled end of the third switching tube Q3, and the delay circuit is used for outputting the first power supply access signal after delaying.
In this embodiment, the delay circuit may be an RC delay circuit, and the RC delay circuit may include a sixth resistor R6 and a first capacitor C1, one end of the sixth resistor R6 is connected to the output end of the first voltage divider circuit, the other end of the sixth resistor R6 is connected to one end of the first capacitor C1, the other end of the first capacitor C1 is grounded, and a common end of the sixth resistor R6 and the first capacitor C1 is connected to the controlled end of the third switching tube Q3. Of course, the delay circuit may be an inverter circuit or other delay circuits.
In this embodiment, when the first power supply is powered off, since the second switch control circuit 20 controls the second power supply to stop outputting the second power supply to the electrical load for a certain time, if the first power supply is controlled to output to the electrical load, the second switch control circuit 20 is controlled to control the second power supply to stop outputting the second power supply to the electrical load. This may cause the first power source and the second power source to be simultaneously connected to the load for a certain time, and further cause the higher voltage power source of the first power source and the second power source to sink the current to the lower voltage power source, resulting in the lower voltage power source being damaged. For example, the first power source is back-flowed to the second power source.
In this embodiment, the delay circuit is disposed in the first control circuit, so that the voltage signal output from the first voltage dividing circuit to the third switching tube Q3 is output after being delayed, and the on-time of the third switching tube Q3 can be delayed, so as to delay the on-time of the first switching circuit. That is, when detecting that the first power supply is powered on, the first switch circuit is not triggered to be turned on immediately, but is turned on after the delay time set by the delay circuit, so that the second switch control circuit 20 can control the second power supply incoming end 40 to be disconnected from the electrical load within the delay time, and it is ensured that when the second power supply is switched to the first power supply to supply power to the electrical load, the connection between the second power supply and the electrical load is firstly disconnected, and then the connection between the first power supply and the electrical load is connected. So set up, can avoid first power and second power to switch on to the power consumption load simultaneously, output current is greater than the electric current of power consumption load, leads to the power consumption load to overflow and damage, can also avoid simultaneously that the higher first power of output voltage flows backward to the lower second power of output voltage through second switch control circuit 20, damages the second power.
In one embodiment, the second switch control circuit 20 includes:
the input end of the second switching circuit is connected with the second power supply access end 40, and the output end of the second switching circuit is connected with an electric load;
and the detection end of the second control circuit is connected with the first power supply access end 30, the output end of the first control circuit is connected with the controlled end of the second switch circuit, and the second control circuit is used for controlling the second switch circuit to be switched on when the first power supply access end 30 is not accessed into the first power supply.
In this embodiment, the second switch circuit may be turned on when receiving a high level signal and turned off when receiving a low level signal, or the second switch circuit may be turned on when receiving a low level signal and turned off when receiving a high level signal; the method is specifically set according to actual requirements.
The second control circuit may determine that the first power supply is powered off/on according to a relationship between the voltage of the first power supply and a preset voltage, for example, when it is detected that the voltage of the first power supply is greater than the preset voltage, it is determined that the first power supply is powered on, and when the voltage of the first power supply is less than the preset voltage, it is determined that the first power supply is powered off, and a corresponding control signal is output to control the second switching circuit to be turned on/off.
In this embodiment, when the first power supply is powered on through the second control circuit, the second switch circuit is controlled to be turned off, so that the situation that the first power supply and the second power supply are simultaneously connected to the power utilization load is avoided, the output current is greater than the current of the power utilization load, and the power utilization load is damaged due to overcurrent is avoided, and meanwhile, the situation that the first power supply with higher output voltage flows backwards to the second power supply with lower output voltage through the second switch control circuit 20 and the second power supply is damaged can also be avoided. When the first power supply is powered down, the second switch circuit is controlled to be turned on, so that the second power supply is output to the electric load to supply power to the electric load.
In some embodiments, the second switching circuit includes a seventh resistor R7 and a fourth switching tube Q4.
The fourth switching tube Q4 may be one or more of a triode, a MOS tube, or an IGBT.
In this embodiment, the fourth switching transistor Q4 is taken as a PMOS transistor for illustration, and is labeled as a third PMOS transistor. The seventh resistor R7 is connected in series between the source and the gate of the third PMOS tube.
In some embodiments, in an embodiment, the second switching circuit further comprises: a second capacitor C2, a first terminal of the second capacitor C2 is connected to the first power supply, and a second terminal of the second capacitor C2 is connected to the gate of the third PMOS. Therefore, when the first power supply is powered off, the second capacitor C2 can charge the gate of the third PMOS, so as to accelerate the cut-off speed of the third PMOS, and ensure that the third PMOS transistor is cut off when the first power supply is powered on, that is, the second switch circuit is cut off, thereby preventing the first power supply from flowing backward to the second power supply through the second switch circuit.
In one embodiment, the second switch control circuit 20 further includes:
a diode D1, wherein the anode of the diode D1 is connected with the input end of the second switch circuit, and the cathode of the diode D1 is connected with the output end of the second switch circuit.
In this embodiment, when the first power source is powered down, the second switch control circuit 20 controls the second power source to output to the electrical load, that is, controls the second switch circuit to be turned on, and a certain time (for example, the on time of the third PMOS transistor in the previous embodiment) is required, which results in a certain time difference between the time when the first power source is powered down and the time when the second power source is output to the electrical load, and in this time difference, the electrical load is not powered by the power source.
In this embodiment, the power voltage of the first power source is set to be greater than the voltage of the second power source. For example, the power supply voltage of the first power supply may be set to be 0.7V or more larger than the voltage of the second power supply.
When the first power supply and the second power supply are both powered on, because the power supply voltage of the first power supply is greater than the voltage of the second power supply, the cathode voltage of the diode D1 is higher than the anode voltage, and the diode D1 is cut off, the first power supply can be prevented from flowing backwards to the second power supply, when the first power supply is powered off, the second power supply immediately supplies power for an electric load through the diode D1, and until the second switch circuit is started, the diode D1 is bypassed, so that the power consumption of the diode D1 can be avoided.
In this embodiment, since the diode D1 does not need to be turned on for a certain time, the second power supply can immediately supply power to the power-consuming load after the first power supply is powered off, thereby increasing the speed of power switching.
In one embodiment, the second control circuit comprises:
the input end of the second voltage division circuit is connected with the first power supply access end 30, and the second voltage division circuit divides the voltage of the first power supply and outputs the divided voltage;
the input end of the inverting circuit is connected with the output end of the second voltage division circuit, and the inverting circuit is used for inverting and outputting the divided first power supply;
and a controlled end of a fourth switching tube Q4 is connected with the output end of the inverter circuit, the input end of the fourth switching tube Q4 is grounded, and the output end of the fourth switching tube Q4 is connected with the controlled end of the second switching circuit.
In this embodiment, the second voltage divider circuit includes an eighth resistor R8 and a ninth resistor R9, one end of the eighth resistor R8 is connected to the first power supply, the other end of the eighth resistor R8 is connected to one end of the ninth resistor R9, and the other end of the ninth resistor R9 is grounded. The common terminal of the eighth resistor R8 and the ninth resistor R9 is the output terminal of the second voltage division circuit. Of course, the second voltage division circuit may also be a voltage reduction chip such as LDO.
The inverter circuit includes: a tenth resistor R10 and a comparator, one end of the tenth resistor R10 is connected with a power supply, such as a 3.3V power supply; the other end of the tenth resistor R10 is connected to the non-inverting input terminal of the comparator, and the inverting input terminal of the comparator is connected to the output terminal of the second voltage divider circuit.
In this embodiment, the second control circuit further includes: an eleventh resistor R11, a twelfth resistor R12 and a thirteenth resistor R13, wherein one end of the eleventh resistor R11 is connected with the output end of the inverter circuit, the other end of the eleventh resistor R11 is connected with one end of the twelfth resistor R12, the other end of the twelfth resistor R12 is grounded, and the common end of the eleventh resistor R11 and the twelfth resistor R12 is connected with the controlled end of the fourth switching tube Q4; the thirteenth resistor R13 is connected in series between the input terminal of the fourth switching tube Q4 and the second switching circuit.
The fourth switching tube Q4 may be one or more of a triode, a MOS tube, or an IGBT. The fourth switching tube Q4 may be turned on when receiving a high signal and turned off when receiving a low signal.
In this embodiment, the second switch circuit is turned on when the controlled terminal is in the low level state, and turned off when the controlled terminal is in the high level state.
When the first power supply is switched on, the first voltage division circuit divides the first power supply into a voltage slightly higher than that of the 3.3V power supply, such as 5V;
when the first power supply is connected, the second voltage division circuit divides the first power supply and outputs the divided voltage, the voltage of the inverting input end of the comparator is higher than that of the non-inverting input end, the comparator outputs a low-level signal, and at the moment, the fourth switching tube Q4 is cut off, so that the controlled end level of the first switching circuit is clamped in a high-level state, and the second switching circuit is controlled to be cut off. When the first power supply is powered down, the second voltage division circuit does not output power, at the moment, the voltage of the non-inverting input end of the comparator is higher than the voltage of the inverting input end, the comparator outputs a high level signal, the fourth switching tube Q4 is turned on, the level of the controlled end of the second switching circuit is pulled down, the controlled end of the second switching circuit is in a low level state, the second switching circuit is controlled to be turned on, and the second power supply is output to the power load.
The utility model also provides medical equipment, which comprises a first power supply, a second power supply, an electric load and the power supply switching circuit;
the specific structure of the power switching circuit refers to the above embodiments, and since the medical device adopts all technical solutions of all the above embodiments, at least all the beneficial effects brought by the technical solutions of the above embodiments are achieved, and no further description is given here.
A first power supply access end 30 of the power supply switching circuit is connected to the first power supply; and a second power supply access end 40 of the power supply switching circuit is connected to the second power supply, and a power supply output end of the power supply switching circuit is connected with the power load.
The above description is only an alternative embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the contents of the present specification and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.
Claims (10)
1. A power switching circuit, comprising:
the first power supply access end is used for accessing a first power supply;
the second power supply access end is used for accessing a second power supply;
the detection end and the input end of the first switch control circuit are both connected with the first power supply access end, and the output end of the first switch control circuit is connected with an electricity load;
the input end of the second switch control circuit is connected with the second power supply access end, the detection end of the second switch control circuit is connected with the first power supply access end, and the output end of the second switch control circuit is connected with the electric load; wherein the content of the first and second substances,
the first switch control circuit is used for controlling the first power supply to output a first power supply to an electric load when the first power supply access end is detected to be connected to the first power supply; and the second switch control circuit is used for controlling the second power supply to output a second power supply to the electric load when detecting that the first power supply access end is not accessed to the first power supply.
2. The power switching circuit according to claim 1, wherein the second switch control circuit is further configured to control the second power supply to stop outputting the second power supply to the electrical load when the first power supply input is detected to be resumed at the first power supply input terminal after the second power supply is controlled to output the second power supply to the electrical load.
3. The power switching circuit of claim 1, wherein the first switch control circuit comprises:
the input end of the first switch circuit is connected with the first power supply access end, and the output end of the first switch circuit is connected with the power utilization load;
the detection end of the first control circuit is connected with the first power supply access end, the output end of the first control circuit is connected with the controlled end of the first switch circuit, and the first control circuit is used for controlling the first switch circuit to be turned on when the first power supply access end is detected to be connected into the first power supply.
4. The power switching circuit of claim 3, wherein the first switching circuit comprises:
the first switch tube and the second switch tube; wherein the content of the first and second substances,
the input end of the first switch tube is connected with the input end of the second switch tube, the output end of the first switch tube is connected with the first power supply access end, and the output end of the second switch tube is connected with the power load.
5. The power switching circuit of claim 3, wherein the first control circuit comprises:
the input end of the first voltage division circuit is connected with the first power supply access end, and the first voltage division circuit divides the voltage of the first power supply and outputs the divided voltage;
and the input end of the third switching tube is grounded, the output end of the third switching tube is connected with the controlled end of the first switching circuit, and the controlled end of the third switching tube is connected with the output end of the first voltage division circuit.
6. The power switching circuit according to any one of claims 3 to 5, wherein the first control circuit further comprises:
and the input end of the delay circuit is connected with the output end of the first voltage division circuit, the output end of the delay circuit is connected with the controlled end of the second switch circuit, and the delay circuit is used for outputting the first power supply access signal after delaying.
7. The power switching circuit of claim 1, wherein the second switch control circuit comprises:
the input end of the second switch circuit is connected with the second power supply access end, and the output end of the second switch circuit is connected with an electric load;
and the detection end of the second control circuit is connected with the first power supply access end, the output end of the first control circuit is connected with the controlled end of the second switch circuit, and the second control circuit is used for controlling the second switch circuit to be switched on when the first power supply access end is not connected into the first power supply.
8. The power switching circuit of claim 7, wherein the second switch control circuit further comprises:
and the anode of the diode is connected with the input end of the second switching circuit, and the cathode of the diode is connected with the output end of the second switching circuit.
9. The power switching circuit of claim 7, wherein the second control circuit comprises:
the input end of the second voltage division circuit is connected with the first power supply access end, and the second voltage division circuit divides the voltage of the first power supply and outputs the divided voltage;
the input end of the inverting circuit is connected with the output end of the second voltage division circuit, and the inverting circuit is used for inverting and outputting the divided first power supply;
and the controlled end of the fourth switching tube is connected with the output end of the inverter circuit, the input end of the fourth switching tube is grounded, and the output end of the fourth switching tube is connected with the controlled end of the second switching circuit.
10. A medical device comprising a first power source, a second power source, and an electrical load and a power switching circuit as claimed in any one of claims 1-9;
a first power supply access end of the power supply switching circuit is connected to the first power supply; and a second power supply access end of the power supply switching circuit is connected to the second power supply, and a power supply output end of the power supply switching circuit is connected with the power load.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202120852960.6U CN215681904U (en) | 2021-04-23 | 2021-04-23 | Power supply switching circuit and medical equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202120852960.6U CN215681904U (en) | 2021-04-23 | 2021-04-23 | Power supply switching circuit and medical equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN215681904U true CN215681904U (en) | 2022-01-28 |
Family
ID=79970822
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202120852960.6U Active CN215681904U (en) | 2021-04-23 | 2021-04-23 | Power supply switching circuit and medical equipment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN215681904U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116742954A (en) * | 2022-09-29 | 2023-09-12 | 荣耀终端有限公司 | Power supply switching circuit and electronic equipment |
-
2021
- 2021-04-23 CN CN202120852960.6U patent/CN215681904U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116742954A (en) * | 2022-09-29 | 2023-09-12 | 荣耀终端有限公司 | Power supply switching circuit and electronic equipment |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106712207B (en) | Reverse connection-preventing and reverse-flowing-preventing battery charging protection circuit | |
| CN101938148B (en) | Battery charging circuit and battery power supply equipment | |
| CN202798027U (en) | Bidirectional power supply circuit of single USB interface | |
| CN212033826U (en) | Power supply circuit and electronic device | |
| CN215681904U (en) | Power supply switching circuit and medical equipment | |
| CN204290464U (en) | Power supply circuits and electronic equipment | |
| CN210297317U (en) | Discrete component dual power supply switching circuit and electronic equipment | |
| CN210629189U (en) | Backup power supply device based on super capacitor | |
| CN104348251A (en) | Circuit for switching power supplies of external power source and lithium battery | |
| CN102118057B (en) | DC UPS circuit with integrated charge-discharge circuit | |
| CN111987710B (en) | Low-power consumption anti-backflow circuit and multi-input power supply device | |
| CN114928147A (en) | Battery charging protection circuit, chip and power module | |
| CN111130210B (en) | Main and standby power management system | |
| CN108832700B (en) | Wake-up and dormancy circuit of Hall switch | |
| CN111030287A (en) | UPS uninterrupted power source system | |
| CN207664602U (en) | Low-power consumption short-circuit protection circuit for DC/DC converters | |
| CN212114765U (en) | Undervoltage protection circuit with hysteresis function applied to products in power industry | |
| CN216649297U (en) | Super capacitor power supply circuit and electric energy meter | |
| CN221151018U (en) | Power-down holding circuit and controller | |
| CN213125621U (en) | Feed type battery charging circuit and medical equipment | |
| CN216599116U (en) | Standby power supply circuit and electric equipment | |
| CN221282863U (en) | Power supply control circuit, power supply system and electronic equipment | |
| CN219497342U (en) | Power-down data storage circuit of electric energy meter | |
| CN221354293U (en) | Switch control circuit and electronic equipment | |
| CN214506641U (en) | Dual-power switching circuit and power supply device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CP01 | Change in the name or title of a patent holder |
Address after: A1302, Shenzhen national engineering laboratory building, No.20, Gaoxin South 7th Road, high tech Zone community, Yuehai street, Nanshan District, Shenzhen, Guangdong 518000 Patentee after: Shenzhen Security Medical Technology Co.,Ltd. Address before: A1302, Shenzhen national engineering laboratory building, No.20, Gaoxin South 7th Road, high tech Zone community, Yuehai street, Nanshan District, Shenzhen, Guangdong 518000 Patentee before: AMBULANC (SHENZHEN) TECH. Co.,Ltd. |
|
| CP01 | Change in the name or title of a patent holder | ||
| CP03 | Change of name, title or address |
Address after: 518000, Building 1, 101, Evergrande Fashion Huigu Building, Fulong Road, Shanghenglang Community, Dalang Street, Longhua District, Shenzhen City, Guangdong Province Patentee after: Shenzhen Security Medical Technology Co.,Ltd. Country or region after: China Address before: A1302, Shenzhen national engineering laboratory building, No.20, Gaoxin South 7th Road, high tech Zone community, Yuehai street, Nanshan District, Shenzhen, Guangdong 518000 Patentee before: Shenzhen Security Medical Technology Co.,Ltd. Country or region before: China |
|
| CP03 | Change of name, title or address |