Power supply

Abstract

The power supply is characterized in that an electric heater between an H pin and an H pin and a resistor R1 are connected in series between an input voltage VDD end and a ground end, a resistor R2 is connected in series between the input voltage VDD end and the ground end, a connecting end B0B1 of a gas sensitive body and the resistor R1 is also communicated with a negative input pin of an operational amplifier U2.1, a capacitor C1 is connected in parallel with the resistor R2, and a negative input pin of the operational amplifier U2.1 is communicated with a negative output pin of the operational amplifier U2.1. A forward end (CW) of the potentiometer RW1 is communicated with an input voltage end VDD, a reverse end (CCW) of the potentiometer RW1 is communicated with a ground end, a moving end (WIPER) of the potentiometer RW1 is communicated with a positive input pin of the operational amplifier U2.1, a resistor R3 is communicated between the input voltage end VDD and an output pin of the operational amplifier U2.1, a capacitor C2 is communicated between the output pin of the operational amplifier U2.1 and the ground end, a positive power supply pin of the operational amplifier U2.1 is communicated with an input power supply VDD, and a negative power supply pin of the operational amplifier U2.1 is communicated with an output power supply VDD. The negative power supply pin is communicated with the ground end, the resistor R7 is communicated with the trigger end of the switching device Q1, the resistor R4 is communicated between the input power supply VDD and the input end of the amplifying device Q1, the resistor R6 is communicated between the output end of the switching device Q1 and the ground end, the communicated end of the resistor R6 and the output end of the amplifying device Q1 is a power supply output end SPVDD, and the communicated end of the resistor R6 and the ground end is a power supply output ground end.

Description

Technical Field

[0001] This application relates to power supplies, and more particularly to power supplies for wireless communication circuits. Background Technology

[0002] Wireless communication circuits typically use a constant power supply, which requires human intervention to cut off.

[0003] Application content

[0004] The purpose of this application is to provide a power supply that automatically cuts off when there is a flammable gas leak.

[0005] To achieve the above objectives, this application provides a power supply: the electric heating circuit of the gas-sensitive element SE1 consists of an electric heater between the HH pins and a resistor R1 connected in series between the input voltage VDD terminal and the ground terminal; the sensing circuit of the gas-sensitive element SE1 consists of a gas sensor and a resistor R2 connected in series between the input voltage VDD terminal and the ground terminal, wherein the connection point B0B1 between the gas sensor and the resistor R1 is also connected to the negative input pin of the operational amplifier U2.1, and the capacitor C1 is connected in parallel with the resistor R2; the threshold preset circuit consists of the positive terminal (CW) of the potentiometer RW1 connected to the input voltage terminal VDD, the reverse terminal (CCW) connected to the ground terminal, and the moving terminal (WIPER) connected to the positive input pin of the operational amplifier U2.1; the monitoring circuit consists of a resistor R3 connected between the input voltage terminal VDD and the output pin of the operational amplifier U2.1, and a capacitor C2 connected to the operational amplifier U2.1. The output pin of operational amplifier U2.1 is connected to ground. The positive power supply pin of operational amplifier U2.1 is connected to the input power supply VDD, and the negative power supply pin is connected to ground. The switching circuit consists of resistor R7 connected to the trigger terminal of switching device Q1, resistor R4 connected between the input power supply VDD and the input terminal of amplifying device Q1, and resistor R6 connected between the output terminal of switching device Q1 and ground. The connection between resistor R6 and the output terminal of amplifying device Q1 is the power output terminal SP_VDD, and the connection between resistor R6 and ground is the power output ground terminal. During normal operation, when the potential of the negative input terminal of operational amplifier U2.1 is lower than that of the positive input terminal, the power output is turned on; when the potential of the negative input terminal of operational amplifier U2.1 is equal to or higher than that of the positive input terminal, the power output is turned off. The rated power output voltage is equal to the difference between the voltage between the input voltage terminal VDD and ground and the voltage drop of amplifying device Q1.

[0006] The gas detection unit consists of a gas-sensitive element SE1, resistors R1 and R2 and capacitor C1; the analysis unit consists of an operational amplifier U2.1, potentiometer RW1, resistor R3 and capacitor C2; and the switching unit consists of a switching device Q1 and resistors R4, R6 and R7.

[0007] The above-mentioned power supply,

[0008] Its characteristics are:

[0009] The gas sensor and resistor R2 are connected at terminal B0B1, which is connected to an analog-to-digital converter pin of the control chip U1. Alternatively, resistor R2 is composed of resistors R2-1 and R2-2 connected in series, and the series connection node of resistors R2-1 and R2-2 is connected to an analog-to-digital converter pin of the control chip U1.

[0010] Alternatively, the moving terminal (WIPER) of potentiometer RW1 can be connected to an analog-to-digital converter pin of control chip U1, or the moving terminal (WIPER) of potentiometer RW1 can be connected to ground in series with resistors R14 and R15, and the series connection point of resistors R14 and R15 can be connected to an analog-to-digital converter pin of control chip U1.

[0011] Alternatively, the power supply output terminal can be connected to an analog-to-digital converter pin of the control chip U1, or the power supply output terminal can be connected to the output ground terminal with resistors R16 and R11 in series, and the series connection node of resistors R16 and R17 can be connected to an analog-to-digital converter pin of the control chip U1.

[0012] The aforementioned power supply is characterized in that: the amplifying device Q1 is a transistor, with its input terminal being the collector, its output terminal being the emitter, and its trigger terminal being the base;

[0013] Alternatively, resistor R4 and transistor Q1 can be combined in digital transistor Q2;

[0014] or,

[0015] a. The amplifying device Q1 is either a field-effect transistor (MOSFET) Q3. Resistor R4 is connected between the output terminal of operational amplifier U2.1 and the gate of MOSFET Q3. Resistor R5 is connected between the input voltage terminal VDD2 and the source of MOSFET Q3. Resistor R6 is connected between the drain of MOSFET Q3 and ground to form a switching circuit.

[0016] b. The amplifying device Q1 or the trench gate field cutoff transistor (IGBT) Q4 forms a switching circuit, and the resistor R4 is connected between the output terminal of the operational amplifier U2.1 and the gate of the trench gate field cutoff transistor (IGBT) Q4.

[0017] c. The amplifying device Q1 is either a thyristor D1 (single-directional controllable silicon). Resistor R4 is connected between the output terminal of operational amplifier U2.1 and the control electrode of thyristor D1 (single-directional controllable silicon). Resistor R5 is connected between the input voltage terminal VDD2 and the anode of thyristor D1 (single-directional controllable silicon). Resistor R6 is connected between the cathode of thyristor D1 (single-directional controllable silicon).

[0018] Alternatively, the amplifying device Q1 or the thyristor D2 (bidirectional thyristor) can be connected by resistor R4 between the output terminal of the operational amplifier U2.1 and the control terminal of the thyristor D2 (bidirectional thyristor), resistor R5 between the input voltage terminal VDD2 and the first anode of the thyristor D2 (bidirectional thyristor), and resistor R6 between the second anode of the thyristor D2 (bidirectional thyristor) to form a switching circuit.

[0019] or,

[0020] a. The amplifier device or Q1 is relay K1. Diode D is connected in parallel with the coil of relay K1. Its cathode is connected to the output terminal of resistor R4, and its anode is connected to ground. Resistor R5 is connected between voltage terminal VDD2 and the output terminal of resistor R4. Resistor R6 is the coil resistance of relay K1. Voltage input / output terminal INOUT1 is connected to the fixed input terminal of relay K1, and voltage input / output terminal INOUT2 is connected to the normally closed contact of relay K1.

[0021] Amplifying device Q1 is either a solid-state relay (SSR). The positive input terminal of the SSR is connected to the output terminal of resistor R4, and the negative input terminal is connected to ground. Resistor R5 is connected between voltage terminal VDD2 and the output terminal of resistor R4. Resistor R6 is the equivalent resistance of the control circuit (including LEDs) in the SSR. Voltage input / output terminal INOUT1 is connected to one load terminal of the SSR, and the other voltage input / output terminal INOUT2 is connected to the other load terminal of the SSR.

[0022] The aforementioned power supply may have either a resistor R18 between voltage input terminals VDD and VDD1, or a resistor R19 between voltage input terminals VDD1 and VDD2; or a resistor R18 between voltage input terminals VDD and VDD1, or a resistor R19 between voltage input terminals VDD1 and VDD2, with capacitor C11 connected in parallel with resistor R18, and capacitor C12 connected in parallel with resistor R19.

[0023] The technical effect of this application is that it enables gas appliances to be connected to the Internet of Things (IoT) when there is no gas leak, and not connected to the IoT when there is a leak. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the power supply principle in Embodiment 1 of this application.

[0025] Figure 2 This is a schematic diagram of the power supply principle in Embodiment 2 of this application.

[0026] Figure 3 This is a schematic diagram illustrating the principle of transistor 2.

[0027] Figure 4 This is a schematic diagram illustrating the principle of resistor and transistor Q2 setup.

[0028] Figure 5 This is a schematic diagram illustrating the working principle of a field-effect transistor (MOSFET).

[0029] Figure 6 This is a schematic diagram illustrating the installation principle of the trench gate field stop tube (IGBT).

[0030] Figure 7 This is a schematic diagram illustrating the working principle of a thyristor (unidirectional silicon controlled rectifier).

[0031] Figure 8 This is a schematic diagram illustrating the working principle of a thyristor (bidirectional controlled silicon).

[0032] Figure 9 This is a schematic diagram of the relay setting principle.

[0033] Figure 10 This is a schematic diagram illustrating the working principle of a solid-state relay.

[0034] Figure 11 This is a schematic diagram of the power supply principle of Embodiment 3 of this application, which contains transistors. Detailed Implementation

[0035] To further illustrate the features of this application, please refer to the following detailed description and accompanying drawings. The drawings are for reference and illustration only and are not intended to limit the scope of protection of this application.

[0036] See Figure 1 and Figure 3The electric heating circuit, including the gas-sensitive element SE1 (model SQ-2), consists of an electric heater between HH and a resistor R1 connected in series between the input voltage VDD terminal and ground. One end of the gas sensor has pins A0 and A1 connected as one unit (or one unit), referred to as the A0A1 terminal. The other end has pins B0 and B1 connected as one unit (or one unit), referred to as the B0B1 terminal. The sensing circuit of the gas-sensitive element SE1 consists of the gas sensor and a resistor R2 connected in series between the input voltage VDD terminal and ground. The connection point B0B1 between the gas sensor and resistor R1 is also connected to the negative input pin of the operational amplifier U2.1. Capacitor C1 is connected in parallel with resistor R2. The threshold preset circuit consists of the positive terminal of potentiometer RW1 (…). The circuit consists of a resistor R3 connected to the input voltage terminal VDD, a capacitor C2 connected to the output terminal of operational amplifier U2.1, a capacitor C2 connected to the output terminal of operational amplifier U2.1 and ground, and a positive power supply pin of operational amplifier U2.1 connected to the input power supply VDD and a negative power supply pin connected to ground. The switching circuit consists of a resistor R7 connected to the trigger terminal of amplifier device Q1, a resistor R4 connected to the input terminal of amplifier device Q1 via the input power supply VDD, and a resistor R6 connected to the output terminal of amplifier device Q1 and ground. The connection between resistor R6 and the output terminal of amplifier Q1 is the power supply output terminal SP_VDD, and the connection between resistor R6 and ground is the power supply output ground terminal. LED2 and resistor R5 are connected in series between the input voltage terminal VDD and the output terminal of operational amplifier U2.1, and capacitor C5 is connected in parallel across LED2. During normal operation, when the negative input terminal potential of operational amplifier U1 is lower than the positive input terminal potential, the power supply output is on, and LED2 is off. When the negative input terminal potential of operational amplifier U2.1 is equal to or higher than the positive input terminal potential, the power supply is off, and LED2 is on. This means that when the concentration of combustible gas causes the negative input terminal potential of operational amplifier U2.1 to be lower than the positive input terminal potential, the power supply output is on. When the input voltage is at a certain level, the operational amplifier U2.1 outputs a high level, and the switching device Q1 is in the open state. When the concentration of combustible gas reaches a level that makes the negative input voltage of operational amplifier U2.1 equal to or higher than the positive input voltage, operational amplifier U2.1 outputs a low level, the amplifying device Q1 is in the non-amplifying state, and the output voltage terminal SP_VDD is close to zero potential. Resistor R6 is connected in parallel with the equivalent total resistance of the controlled power circuit. In this example, the rated voltage value of the power supply output voltage terminal SP_VDD to the output ground terminal is equal to the voltage between the input voltage terminal VDD and the ground terminal minus the voltage drop of the amplifying device Q1. The light-emitting diode LED2 and resistor R5 are connected in series between the input voltage terminal VDD and the output terminal of operational amplifier U2.1.

[0037] The power output terminal SP_VDD and the power output ground terminal are connected to the corresponding power and ground pins of the WIFI chip U3. The serial port pins U0_TXD and U0_RXD of the wireless communication chip U3 are connected to the serial port pins of the control chip U1 to form an IoT communication device, which can communicate wirelessly with other IoT devices through the antenna.

[0038] Alternatively, the cathode of diode D1 can be connected to the serial port pin U0_TXD of wireless communication chip U3, and the anode to the serial port pin RXD of control chip U1. The cathode of diode D2 can be connected to the serial port pin TXD of control chip U1, and the anode to the serial port pin U0_RXD of wireless communication chip U3, thus forming an IoT communication device that can communicate wirelessly with other IoT devices through an antenna.

[0039] Under normal operating conditions, without gas leakage, the aforementioned IoT device receives normal power and can communicate wirelessly with other devices in the IoT. Conversely, when the gas leakage concentration reaches or exceeds the threshold set by the threshold preset circuit, the normal power supply to the wireless communication chip U3 is shut off, and the wireless communication channel of this IoT device is removed.

[0040] In the above embodiments:

[0041] The gas sensor and resistor R2 are connected at terminal B0B1, which is connected to an analog-to-digital converter pin of control chip U1.

[0042] The moving terminal (WIPER) of potentiometer RW1 is connected to an analog-to-digital converter pin of control chip U1;

[0043] The power supply output terminal is connected to an analog-to-digital conversion pin of the control chip U1, or the power supply output terminal is connected to the output ground terminal by series resistors R16 and R11, and the series node of resistors R16 and R17 is connected to an analog-to-digital conversion pin of the control chip U1.

[0044] In the above embodiments:

[0045] The WIFI chip can be replaced with a Bluetooth chip, a 2.4GHz wireless communication chip, a 4G communication chip, a 5G communication chip, or a satellite communication chip, or any other wireless communication chip.

[0046] See Figure 2 , Figure 1 The resistor R2 is replaced by resistors R2-1 and R2-2 connected in series. The series connection node of resistors R2-1 and R2-2 is connected to an analog-to-digital conversion pin of the control chip U1.

[0047] Figure 1The moving end (WIPER) of potentiometer RW1 is connected to ground in series with resistors R14 and R15. The series connection of resistors R14 and R15 is connected to an analog-to-digital converter pin of control chip U1.

[0048] Figure 1 The power output terminal and the output ground terminal are connected in series with resistors R16 and R11. The series connection node of resistors R16 and R17 is connected to an analog-to-digital conversion pin of the control chip U1.

[0049] The rest is the same as the previous embodiment.

[0050] See Figure 3 In Embodiment 1 and Embodiment 2, the amplifying device Q1 is a transistor Q1-0, whose input terminal is the collector, output terminal is the emitter, and trigger terminal is the base.

[0051] See Figure 4 In Embodiment 1 and Embodiment 2, the amplifying device Q1 is a digital transistor Q2 composed of a resistor and a transistor.

[0052] See Figure 5 In Embodiment 1 and Embodiment 2, the amplifying device Q1 is a field-effect transistor Q3, and the resistor R20 is connected between the gate and ground.

[0053] See Figure 6 In Embodiment 1 and Embodiment 2, the amplifying device Q1 is a trench gate field stop transistor (IGBT) Q4.

[0054] See Figure 7 In both Embodiment 1 and Embodiment 2, the amplifying device Q1 is a thyristor (silicon controlled rectifier) ​​D1.

[0055] See Figure 8 In both Embodiment 1 and Embodiment 2, the amplifying device Q1 is a thyristor (bidirectional silicon controlled rectifier) ​​D2.

[0056] See Figure 9 In both Embodiment 1 and Embodiment 2, the amplifying device Q1 is a relay K1, with its coil connected between resistor R4 and ground.

[0057] See Figure 10 In Embodiment 1 and Embodiment 2, the amplifying device Q1 is a solid-state relay (SSR), wherein the LED anode is connected to the input voltage terminal VDD, and the LED cathode is connected to the ground terminal.

[0058] See Figure 11 ,

[0059] For ease of explanation, let VDD1 = VDD when R18 = 0, and VDD1 = VDD2 = VDD when R19 = 0. An example is shown below:

[0060] In Embodiment 1 and Embodiment 2, the amplifying device Q1 is replaced by transistor Q1-0, and the communication chip U3 is replaced by microcontroller U4. The positive power supply pin VDD and the ground pin VSS of microcontroller U4 correspond to the output power supply terminal and the output ground terminal of the power supply. The input voltage terminal VDD and VDD1 are connected in series with a resistor. The rest is the same as in Embodiment 1 or Embodiment 2. Microcontroller U4 is then connected to WIFI chip U3.

[0061] Alternatively, in Embodiment 1 and Embodiment 2, the amplifying device Q1 is transistor Q1-0, and the communication chip U3 is replaced by microcontroller U4. The positive power supply pin VDD and the ground pin VSS of microcontroller U4 correspond to the output power supply terminal and the output ground terminal connected to the power supply. There is a resistor R18 between voltage input terminal VDD and voltage input terminal VDD1, and a resistor R19 between voltage input terminal VDD1 and voltage input terminal VDD2. Capacitor C11 is connected in parallel with resistor R18, and capacitor C12 is connected in parallel with resistor R19. The rest is the same as in Embodiment 1 or Embodiment 2.

[0062] The above circuit,

[0063] When R18≠0, VDD1≠VDD; when R19≠0, VDD1≠VDD2, meaning the power supply voltages of the detection unit, analysis unit, and switching unit are not equal. Alternatively, when R18=0, VDD1=VDD; when R19≠0, VDD1≠VDD2, meaning the power supply voltages of the detection unit and analysis unit are equal, while the power supply voltages of the switching unit are not equal to those of these two units. Or, when R18≠0, VDD1≠VDD; when R19=0, VDD1=VDD2, meaning the power supply voltages of the detection unit and analysis unit are not equal, while the power supply voltages of the analysis unit and switching unit are equal.

[0064] Best practice

[0065] See Figure 1 and Figure 3 or Figure 2 and Figure 3 When the switching device Q1 of the power supply in this application is a transistor Q1-0, the structure is simple, easy to manufacture, and low in cost, and it can be widely used in Internet of Things devices that operate in environments where flammable gases are present.

[0066] The power supply for this application can be implemented using conventional methods.

Claims

1. A power supply: the electric heating circuit of the gas sensitive element SE1 is composed of the electric heater between the H-H pins and the resistor R1 in series between the input voltage VDD terminal and the ground terminal; the sensing circuit of the gas sensitive element SE1 is composed of the gas sensitive body and the resistor R2 in series between the input voltage VDD terminal and the ground terminal, wherein, The gas sensitive body is connected with the end B0B1 of the resistor R1, and the end B0B1 is also communicated with the negative input pin of the operational amplifier U2.1, and the capacitor C1 is connected with the resistor R2 in parallel; the threshold preset circuit is composed of the positive end (CW) of the potentiometer RW1 communicated with the input voltage end VDD, the reverse end (CCW) communicated with the ground end, and the moving end (WIPER) communicated with the positive input pin of the operational amplifier U2.1; the monitoring circuit is composed of the resistor R3 communicated between the input voltage end VDD and the output pin of the operational amplifier U2.1, and the capacitor C2 communicated between the output pin of the operational amplifier U2.1 and the ground end, and the positive power supply pin of the operational amplifier U2.1 is communicated with the input power supply VDD, and the negative power supply pin is communicated with the ground end; the switch circuit is composed of the resistor R7 communicated with the trigger end of the switching device Q1, the resistor R4 communicated between the input power supply VDD and the input end of the amplifying device Q1, and the resistor R6 communicated between the output end of the switching device Q1 and the ground end, and the output end of the resistor R6 and the output end of the amplifying device Q1 are the power supply output end SP_VDD, and the ground end of the resistor R6 is the power supply output ground end; in the normal working state, when the potential of the negative input end of the operational amplifier U2.1 is lower than the potential of the positive input end, the power supply output is opened, and when the potential of the negative input end of the operational amplifier U2.1 is equal to or higher than the potential of the positive input end, the power supply output is closed.

2. The power supply of claim 1, wherein: The end B0B1 of the resistor R2 is communicated with a module / number conversion pin of the control chip U1, or the resistor R2 is composed of the resistor R2-1 and the resistor R2-2 connected in series, and the series connection node of the resistor R2-1 and the resistor R2-2 is communicated with a module / number conversion pin of the control chip U1.

3. The power supply of claim 1, wherein: The moving end (WIPER) of the potentiometer RW1 is communicated with a module / number conversion pin of the control chip U1, or the moving end (WIPER) of the potentiometer RW1 is connected with the ground end in series with the resistor R14 and the resistor R15, and the series connection node of the resistor R14 and the resistor R15 is communicated with a module / number conversion pin of the control chip U1.

4. The power supply of claim 1, wherein: The power supply output power end is communicated with a module / number conversion pin of the control chip U1, or the power supply output power end is connected with the output ground end in series with the resistor R16 and the resistor R11, and the series connection node of the resistor R16 and the resistor R17 is communicated with a module / number conversion pin of the control chip U1.

5. The power supply of claim 1 or 2 or 3 or 4, characterized by: The amplifying device Q1 is a transistor Q1-0, the input end is the collector, the output end is the emitter, and the trigger end is the base.

6. A power supply according to claim 5, characterised in that: The resistor and the transistor are combined in the digital transistor Q2.

7. The power supply according to claim 1 or 2 or 3 or 4, characterized in that: a. the amplifying device Q1 is a field effect transistor (MOSFET) Q3, the resistor R4 is connected between the output end of the operational amplifier U2.1 and the gate of the field effect transistor (MOSFET) Q3, the resistor R5 is connected between the input voltage end VDD2 and the source of the field effect transistor (MOSFET) Q3, and the resistor R6 is connected between the drain of the field effect transistor (MOSFET) Q3 and the ground end to form a switch circuit. b. amplifier device Q1 or is a trench gate field stop tube (IGBT) Q4, resistor R4 is connected between the output of operational amplifier U2.1 and the gate of trench gate field stop tube (IGBT) Q4; c. amplifier device Q1 or is a thyristor D1 (unilateral controllable silicon), resistor R4 is connected between the output of operational amplifier U2.1 and the control electrode of thyristor D1 (unilateral controllable silicon), resistor R5 is connected between input voltage terminal VDD2 and the anode of thyristor D1 (unilateral controllable silicon) Q1, and resistor R6 is connected between the cathode of thyristor (unilateral controllable silicon) D1 to form a switching circuit.

8. The power supply circuit according to claim 1 or 2 or 3 or 4, characterized by:

9. The power supply according to claim 1 or 2 or 3 or 4, characterized in that: a. amplifier device Q1 or is a relay K1, diode D is connected in parallel with the coil of relay K1, the cathode of which is connected with the output of resistor R4, and the anode of which is connected with the ground terminal, resistor R5 is connected between voltage terminal VDD2 and the output of resistor R4, resistor R6 is the coil resistance of relay K1, voltage input / output terminal INOUT1 is connected with the fixed input terminal of relay K1, and voltage input / output terminal INOUT2 is connected with the normally closed contact of relay K1. b. amplifier device Q1 or is a solid-state relay SSR, the positive input terminal of solid-state relay SSR is connected with the output of resistor R4, and the negative input terminal is connected with the ground terminal, resistor R5 is connected between voltage terminal VDD2 and the output of resistor R4, resistor R6 is the equivalent resistance of the control circuit (which includes a light-emitting diode) in solid-state relay SSR, voltage input / output terminal INOUT1 is connected with one load terminal of solid-state relay SSR, and the other voltage input / output terminal INOUT2 is connected with the other load terminal of solid-state relay SSR. There is resistor R18 between voltage input terminal VDD and voltage input terminal VDD1, and there is resistor R19 between voltage input terminal VDD1 and voltage input terminal VDD2; or, there is resistor R18 between voltage input terminal VDD and voltage input terminal VDD1, there is resistor R19 between voltage input terminal VDD1 and voltage input terminal VDD2, capacitor C11 is connected in parallel with resistor R18, and capacitor C12 is connected in parallel with resistor R19.

10. The power supply of claim 1 or 2 or 4 or 5, characterized by: ​

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