An electronic device having a boost circuit.

Abstract

To provide an electronic apparatus having a booster circuit which can continue a booster operation without an additional circuit for continuing a booster operation of the booster circuit.SOLUTION: An electronic apparatus including a booster circuit, comprises: an input terminal 101; a first power storage capacity 102; a second power storage capacity 104; a first rectifier element 103; a voltage detection circuit 106; and a booster circuit 105. The input terminal 101 is connected to the first terminal of the first power storage capacity 102, and the first terminal and a node 109 of the second power storage capacity 104 via the first rectifier element 103, and a voltage detection terminal 151 of the voltage detection circuit 106 is connected to the node 109. A detection signal output terminal 152 of the voltage detection circuit 106 is connected to a detection signal input terminal 154 of the booster circuit 105. A booster power input terminal 153 of the booster circuit 105 is connected to the first terminal of the first power storage capacity 102, and a booster power output terminal 155 of the booster circuit 105 is connected to the node 109.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an electronic device having a boost circuit. [Background technology]

[0002] When input power is converted into boosted power by a boost circuit, the input power must be equal to or greater than the self-power consumption of the boost circuit in order for the boost circuit to operate. Therefore, a configuration has been proposed for conventional electronic devices with boost circuits in which a storage capacitor is provided at the input of the boost circuit, and the power required to operate a load for a predetermined period of time is stored in this storage capacitor, and the boost circuit is operated by the power stored in this storage capacitor (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-085888 Summary of the Invention [Problem to be solved by the invention]

[0004] In conventional electronic devices with a boost circuit, when the storage voltage of the storage capacitor rises, the boost circuit starts boosting operation based on a voltage detection circuit that detects the storage voltage. Once the boost circuit starts boosting operation, the storage voltage of the storage capacitor drops, and when it drops below the detection release voltage of the voltage detection circuit, the boost operation of the boost circuit stops. For this reason, once the boost circuit starts operating, it is necessary to add a circuit that functions to continue operation regardless of the output signal of the voltage detection circuit. In other words, this additional circuitry increases the cost of electronic devices with conventional boost circuits. An object of the present invention is to provide an electronic device with a boost circuit that maintains the boost operation of the boost circuit without adding any additional circuitry. [Means for solving the problem]

[0005] The electronic device having the boost circuit of the present invention includes an input terminal, a first storage capacitor, a second storage capacitor, a first rectifying element, and a first terminal of the second storage capacitor connected to the first terminal of the second storage capacitor; A voltage detection terminal to which a voltage is input, and a voltage detection terminal Storage of the second storage capacity a voltage detection circuit having a detection signal output terminal that outputs a detection signal when a voltage is equal to or higher than a detection voltage; and a boost circuit that converts storage power stored in the first storage capacitor into boosted power and stores the boosted power in the second storage capacitor, wherein the input terminal is connected to a first terminal of the first storage capacitor and, via the first rectifying element, to a node, a voltage detection terminal of the voltage detection circuit is connected to the node, a detection signal output terminal of the voltage detection circuit is connected to a detection signal input terminal of the boost circuit, a boosted power input terminal of the boost circuit is connected to the first terminal of the first storage capacitor, and a boosted power output terminal of the boost circuit is connected to the node, and the boost circuit receives an input from the voltage detection terminal based on the detection signal input to the detection signal input terminal. Storage of the second storage capacity The conversion operation is started when it is determined that the voltage is equal to or greater than the detection voltage. [Effects of the Invention]

[0006] According to the electronic device having the boost circuit of the present invention, it is possible to provide an electronic device having a boost circuit that can sustain a boost operation without adding a circuit that functions to sustain the boost operation. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a circuit diagram showing an example of a first embodiment of the present invention. [Figure 2] FIG. 10 is a circuit diagram showing an example of a second embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0008] [First embodiment] A first embodiment of the present invention will now be described with reference to the drawings, in which: Fig. 1 is a circuit diagram showing an example of an electronic device having a boost circuit according to this embodiment.

[0009] An electronic device 100 having a boost circuit of a first embodiment of the present invention includes an input terminal 101, a first storage capacitor 102, a first rectifying element 103, a second storage capacitor 104, a boost circuit 105, a voltage detection circuit 106, a second rectifying element 107, an output terminal 108, and a node 109.

[0010] The connections of the electronic device 100 having a boost circuit will be described. The input terminal 101 is connected to a first terminal of the first storage capacitor 102, a first terminal of the first rectifier element 103, and a boosted power input terminal 153 of the boost circuit 105. The second terminal of the first rectifier element 103 is connected to a first terminal of the second storage capacitor 104 and to a voltage detection terminal 151 of the voltage detection circuit 106 via a node 109. The detection signal output terminal 152 of the voltage detection circuit 106 is connected to a detection signal input terminal 154 of the boost circuit 105. The boosted power output terminal 155 of the boost circuit 105 is connected to a first terminal of the second rectifier element 107 and to an output terminal 108. The second terminal of the second rectifier element 107 is connected to the first terminal of the second storage capacitor 104 via a node 109. The second terminal of the first storage capacitor 102 and the second terminal of the second storage capacitor 104 are connected to the GND terminal. A description of the connections to the GND terminal will be omitted.

[0011] The operation of the electronic device 100 having the boost circuit of the first embodiment will be described. Power input to the input terminal 101 is stored in the first storage capacitor 102 and, at the same time, stored in the second storage capacitor 104 via the first rectifying element 103. The boost circuit 105 receives the stored power of the first storage capacitor 102 at a boosted power input terminal 153. The voltage detection circuit 106 detects the stored voltage of the second storage capacitor 104 connected to the voltage detection terminal 151, and outputs a detection signal from a detection signal output terminal 152 when it detects that the stored voltage of the second storage capacitor 104 has reached a predetermined voltage or higher. When the detection signal output from the detection signal output terminal 152 of the voltage detection circuit 106 is input to the detection signal input terminal 154, the boost circuit 105 converts the stored power of the first storage capacitor 102 connected to the boosted power input terminal 153 into boosted power. The boost circuit 105 outputs the boosted power from a boosted power output terminal 155. The boosted power output from the boost circuit 105 is output from an output terminal 108 and is stored in the second storage capacitor 104 via the second rectifying element 107 at the same time.

[0012] Here, when the voltage at voltage detection terminal 151 becomes equal to or greater than a predetermined detection voltage, voltage detection circuit 106 outputs a detection signal from detection signal output terminal 152. Furthermore, when the voltage at voltage detection terminal 151 becomes equal to or less than a predetermined detection release voltage that is lower than the detection voltage, voltage detection circuit 106 stops outputting the detection signal from detection signal output terminal 152.

[0013] With the above configuration, when the first storage capacitor 102 is charged, the second storage capacitor 104 is also charged. When the second storage capacitor 104 is charged to a predetermined storage voltage at which a detection signal is output from the voltage detection circuit 106, the voltage detection circuit 106 outputs a detection signal. When the detection signal is input to the detection signal input terminal 154 of the boost circuit 105, the boost circuit 105 converts the stored power of the first storage capacitor 102 into boosted power. When the boost circuit 105 starts operating, the storage voltage of the first storage capacitor 102 decreases, but the storage voltage of the second storage capacitor 104 does not decrease simultaneously with the storage voltage of the first storage capacitor 102 due to the presence of the first rectifier element 103. When the boost circuit 105 starts operating, it outputs the converted boosted power from the boosted power output terminal 155. The boosted power output from the boost circuit 105 is stored in the second storage capacitor via the second rectifier element 107. The boosted power output from the boost circuit 105 keeps the storage voltage of the second storage capacitor 104 higher than the detection release voltage of the voltage detection circuit 106. This allows the voltage detection circuit 106 to continue outputting a detection signal, and the boost circuit 105 to continue its boosting operation without stopping.

[0014] The boost circuit 105 continues the boost operation using the stored power stored in the first storage capacitor 102. When the stored power in the first storage capacitor 102 becomes smaller than the value that can operate the boost circuit 105, the boost circuit 105 stops the boost operation.

[0015] In this way, in the electronic device 100 having the boost circuit of this embodiment, power is first input to the input terminal 101, and power is stored in the first storage capacitor 102 and the second storage capacitor 104. Next, when the storage voltage of the second storage capacitor 104 reaches a predetermined voltage, the boost circuit 105 starts operating. Finally, when the stored power of the first storage capacitor 102 becomes small, the boost circuit 105 stops operating.

[0016] As described above, according to the electronic device 100 having the boost circuit of this embodiment, the boosted power output by the boost circuit 105 can maintain the stored voltage of the second storage capacitor 104, which once became equal to or higher than the detection voltage of the voltage detection circuit 106, at a voltage higher than the detection release voltage of the voltage detection circuit 106. Therefore, it is possible to provide an electronic device having a boost circuit that can continue the boost operation without requiring an additional circuit for maintaining the boost operation of the boost circuit 105.

[0017] [Second embodiment] A second embodiment of the present invention will now be described with reference to the drawings, in which: Fig. 2 is a circuit diagram showing an example of an electronic device having a boost circuit according to this embodiment.

[0018] An electronic device 200 having a boost circuit of the second embodiment of the present invention includes an input terminal 101, a first storage capacitor 102, a first rectifying element 103, a second storage capacitor 104, a voltage detection circuit 106, a coil 201, a first N-channel MOS transistor 202, a second N-channel MOS transistor 206, and a control circuit 204. Here, the first rectifying element 103, the second storage capacitor 104, the coil 201, the first N-channel MOS transistor 202, the second N-channel MOS transistor 206, and the control circuit 204 constitute a boost circuit 205.

[0019] The connections of the electronic device 200 having a boost circuit will be described. The input terminal 101 is connected to a first terminal of the first storage capacitor 102 and a first terminal of the coil 201 via a boosted power input terminal 254 of the boost circuit 205. The second terminal of the coil 201 is connected to a first terminal of the first rectifier element 103 and a drain terminal of the first N-channel MOS transistor 202. The second terminal of the first rectifier element 103 is connected to a power supply terminal 252 of the control circuit 204, a first terminal of the second storage capacitor 104, and a node 109 via a boosted power output terminal 256 of the boost circuit 205. The node 109 is connected to the output terminal 108 and a voltage detection terminal 151 of the voltage detection circuit 106. The control signal output terminal 251 of the control circuit 204 is connected to the gate terminal of the first N-channel MOS transistor 202. The drain terminal of the second N-channel MOS transistor 206 is connected to a GND potential input terminal 253 of the control circuit 204 and the source terminal of the first N-channel MOS transistor 202. The detection signal output terminal 152 of the voltage detection circuit 106 is connected to the gate terminal of the second N-channel MOS transistor 206 via a detection signal input terminal 255 of the boost circuit 205. The second terminal of the first storage capacitor 102, the second terminal of the second storage capacitor 104, and the source terminal of the second N-channel MOS transistor 206 are connected to the GND terminal. A description of the connections to the GND terminal will be omitted.

[0020] The operation of the electronic device having the boost circuit of the second embodiment will be described. The power input to the input terminal 101 is stored in the first storage capacitor 102 and, at the same time, is input to a boosted power input terminal 254 of the boost circuit 205. The power input from the boosted power input terminal 254 of the boost circuit 205 is supplied to the drain terminal of the first N-channel MOS transistor 202 via the coil 201, and is also supplied to a power supply terminal 252 of the control circuit 204 and the second storage capacitor 104 via the coil 201 and the first rectifying element 103. The second storage capacitor 104 is charged with the supplied power at the same time as the first storage capacitor 102. The power stored in the second storage capacitor 104 is output from a boosted power output terminal 256 of the boost circuit 205 and input to a voltage detection terminal 151 of the voltage detection circuit 106. The voltage detection circuit 106 detects the storage voltage of the second storage capacitor 104 connected to the voltage detection terminal 151, and when it detects that the storage voltage of the second storage capacitor 104 has reached a predetermined voltage or higher, it outputs a detection signal from the detection signal output terminal 152. The detection signal output from the voltage detection circuit 106 is input to the gate terminal of the second N-channel MOS transistor 206 via the detection signal input terminal 255 of the boost circuit 205, and the second N-channel MOS transistor 206 is turned on. With the second N-channel MOS transistor 206 in the on state, the GND potential input terminal 253 of the control circuit 204 and the source terminal of the first N-channel MOS transistor 202 are connected to the GND terminal.

[0021] When the GND potential input terminal 253 of the control circuit 204 is connected to the GND terminal, the control circuit 204 inputs a switching signal for switching the first N-channel MOS transistor 202 from the control signal output terminal 251 to the gate terminal of the first N-channel MOS transistor 202. Since the source terminal of the first N-channel MOS transistor 202 is connected to the GND terminal, the coil current generated every time the first N-channel MOS transistor 202 is turned on is stored in the second storage capacitor 104 via the first rectifier element 103 every time the first N-channel MOS transistor 202 is turned off, and is simultaneously output from the boosted power output terminal 256. In this way, the boost circuit 205 outputs boosted power from the boosted power output terminal 256.

[0022] With the above configuration, when the first storage capacitor 102 is charged, the second storage capacitor 104 is also charged via the coil 201 and the first rectifying element 103. When the second storage capacitor 104 is charged to a predetermined storage voltage at which a detection signal is output from the voltage detection circuit 106, the voltage detection circuit 106 outputs a detection signal to the boost circuit 205, and the boost circuit 205 converts the stored power of the first storage capacitor 102 into boosted power. When the boost circuit 205 starts operating, the storage voltage of the first storage capacitor 102 drops, but the storage voltage of the second storage capacitor 104 does not drop simultaneously with the storage voltage of the first storage capacitor 102 due to the presence of the first rectifying element 103. When the boost circuit 205 starts operating, the boost voltage is stored in the second storage capacitor 104, and the stored voltage of the second storage capacitor 104 is maintained higher than the detection release voltage of the voltage detection circuit 106. Therefore, the voltage detection circuit 106 can continue to output a detection signal, and the boost circuit 205 can continue its boost operation without stopping.

[0023] The boost circuit 205 continues the boost operation using the stored power stored in the first storage capacitor 102. When the stored power in the first storage capacitor 102 becomes smaller than the value that can operate the boost circuit 205, the boost circuit 205 stops the boost operation.

[0024] In this way, in the electronic device 200 having the boost circuit of this embodiment, power is initially input to the input terminal 101, and power is stored in the first storage capacitor 102 and the second storage capacitor 104. Next, when the storage voltage of the second storage capacitor 104 reaches a predetermined voltage, the boost circuit 205 starts operating. Finally, when the stored power of the first storage capacitor 102 becomes small, the boost circuit 205 stops operating.

[0025] As described above, according to the electronic device 200 having the boost circuit of this embodiment, the boosted power output by the boost circuit 205 can maintain the stored voltage of the second storage capacitor 104, which once became equal to or higher than the detection voltage of the voltage detection circuit 106, at a voltage higher than the detection release voltage of the voltage detection circuit 106. Therefore, it is possible to provide an electronic device having a boost circuit that can continue the boost operation without requiring an additional circuit for continuing the boost operation of the boost circuit 205.

[0026] According to the electronic device having a boost circuit of the present invention, it is possible to provide an electronic device having a boost circuit that can continue boosting operation without the need for an additional circuit for continuing the boosting operation of the boost circuit, which was conventionally required.

[0027] Although the embodiments of the present invention have been described above in detail with reference to the drawings, the specific configuration is not limited to these embodiments and includes designs that do not deviate from the gist of the present invention. These embodiments and their modifications are included in the scope and spirit of the inventions, and are also included in the inventions described in the claims and their equivalents. [Explanation of symbols]

[0028] 100, 200 Electronic device having a boost circuit 101 Input terminal 102, 104 Storage capacity 103, 107 Rectifying element 105 Boost circuit 106 Voltage detection circuit 108 Output terminal 109 nodes 151 Voltage detection terminal 152 Detection signal output terminal 153 Boost power input terminal 154 Detection signal input terminal 155 Boost power output terminal 201 Coil

Claims

1. An input terminal, a first storage capacity; a second storage capacity; and a first rectifying element; a voltage detection circuit connected to a first terminal of the second storage capacitor, the voltage detection terminal receiving a storage voltage of the second storage capacitor, and a detection signal output terminal configured to output a detection signal when the storage voltage of the second storage capacitor input from the voltage detection terminal is equal to or greater than a detection voltage; a boosting circuit that converts the stored power stored in the first storage capacitor into boosted power and stores the boosted power in the second storage capacitor; the input terminal is connected to a node including a first terminal of the first storage capacitor and a first terminal of the second storage capacitor via the first rectifying element; a detection signal output terminal of the voltage detection circuit is connected to a detection signal input terminal of the voltage boost circuit; a boosted power input terminal of the boost circuit is connected to a first terminal of the first storage capacitor; a boosted power output terminal of the boost circuit is connected to the node; The electronic device having a boost circuit, characterized in that the boost circuit starts the conversion operation when it is determined that the storage voltage of the second storage capacitance input from the voltage detection terminal is equal to or higher than the detection voltage based on the detection signal input to the detection signal input terminal.

2. 2. The electronic device having a boost circuit according to claim 1, further comprising a second rectifying element between the boosted power output terminal of the boost circuit and the node.

3. 2. The electronic device having a boost circuit according to claim 1, further comprising a coil between the first terminal of the first storage capacitor and the first rectifying element.

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