Power supply device

Abstract

To reduce the power consumption of a start-up circuit in a low power consumption mode to further reduce the power consumption in this state. A power supply device has a battery module (10) with a plurality of chargeable battery cells (1), a battery connection circuit (2) with a switching function for a low power consumption mode connected to the battery module (10), a start-up circuit (3) for starting the battery connection circuit (2), and a start-up switch (4) connected to the start-up circuit (3) and outputting a start-up signal. The start-up circuit (3) has an input transistor (5) connected between the base and the emitter of the start-up switch (4) and switched to the off state by the on signal of the start-up switch (4), an FET output circuit (6) connected to the output side of the input transistor (5) for switching the input transistor (5) from on to off and outputting a start-up signal to the battery connection circuit (2) in the low power consumption state.

Description

Technical Field

[0001] This invention relates to a power supply device having a battery module comprising multiple battery cells, and more particularly to a power supply device having a battery connection circuit that can switch to a low-power mode when the battery module is connected. Background Technology

[0002] A power supply device that connects multiple battery cells in series and parallel detects the status of each battery cell and controls the charging and discharging current to protect the battery cells. This power supply device includes: a battery connection circuit that detects the voltage, temperature, and current of the battery cells constituting the battery module, processes the detected signals, and controls the charging and discharging of the battery module. To prevent over-discharge of the battery, when the device is not in use, the power supply device switches to a low-power mode, such as a shutdown state, to minimize the power consumption of the battery connection circuit. The power supply device also includes a startup circuit that restarts the battery connection circuit from its low-power mode to switch to the operating mode.

[0003] The startup circuit, as disclosed in Patent Document 1, can be configured to output a startup signal by pressing a button on a manual operation switch. In this startup circuit, a switch is connected between the power supply circuit and the ground wire via a current-limiting resistor, and the startup signal is output using an on signal from the switch. However, because this startup circuit switches the switch from off to on and outputs the startup signal from the connection point between the load resistor and the switch, in the on state, current flows through the contact point in the switch via the load resistor, and in the off state, the voltage between the contacts rises to the power supply voltage. This drawback can be eliminated by configuring the circuit structure as follows: the switch is connected to the gate of the FET, and the gate voltage of the FET is controlled by the on / off state of the switch, thereby switching the FET on / off using the switch.

[0004] Specifically, such as Figure 2As shown, the circuit structure can be implemented as follows: a start switch 94 is connected between the gate of the input FET 95 and the ground line 99, and the start switch 94 is used to switch the input FET 95 on and off. The start switch 94 is mainly a normally open manual switch, which is on when the button is pressed and off when not pressed. The user presses the button to turn on the start switch 94 when the battery connection circuit 92 in low-power mode is activated. If the normally open switch is turned on by pressing the button, the input FET 95 is switched from on to off. When the button is not pressed, the input FET 95 remains on. The input FET 95 in the on state is connected to the power supply line 98 through the load resistor 96, and a drain current flows between the drain and source as shown by arrow A. Furthermore, in order to keep the input FET 95 in the on state, a bias current flows through the bias resistor 97 connected to the gate to maintain the gate voltage at a given voltage, as shown by arrow B. Although the drain current and bias current can be reduced by increasing the resistance of the load resistor 96 and the bias resistor 97, increasing the resistance becomes a factor that hinders the stability of the operation.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: JP Re-Table 2006 / 059511 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] The present invention was developed with the aim of further solving the above-mentioned problems. An important objective of the present invention is to provide a power supply device that can reduce the power consumption of the startup circuit in low-power mode, thereby further reducing the power consumption in this state.

[0010] Methods for solving problems

[0011] A power supply device according to a certain aspect of the present invention includes: a battery module having a plurality of rechargeable battery cells; a battery connection circuit connected to the battery module and having a low-power mode switching function; a startup circuit for activating the battery connection circuit; and a startup switch connected to the startup circuit and outputting a startup signal. The startup circuit includes: an input transistor connected to the base and emitter of which the startup switch is switched to an off state by an on signal from the startup switch; and a FET output circuit connected to the output side of the input transistor, which switches the input transistor from on to off and outputs a startup signal to the battery connection circuit in a low-power state.

[0012] Invention Effects

[0013] The power supply device of the present invention has the advantage of reducing the power consumption of the startup circuit, thereby saving power. Attached Figure Description

[0014] Figure 1 This is a circuit diagram of a power supply device according to one embodiment of the present invention.

[0015] Figure 2 This is a circuit diagram of an existing power supply device. Detailed Implementation

[0016] A power supply device according to one embodiment of the present invention includes: a battery module having a plurality of rechargeable battery cells; a battery connection circuit connected to the battery module and having a low-power mode switching function; a startup circuit that starts the battery connection circuit in the low-power mode; and a startup switch connected to the startup circuit and outputting a startup signal. The startup circuit includes: an input transistor connected to the startup switch between its base and emitter, which is switched to an off state by an on signal from the startup switch; and a FET output circuit connected to the output side of the input transistor, which switches the input transistor from on to off and outputs a startup signal to the battery connection circuit in the low-power state.

[0017] The startup circuit of the power supply device described above uses a bipolar transistor (BPT) as the input transistor in a semiconductor switching element that switches between on and off states using a start switch. Since a transistor switches to the on state by current flowing through its base, its input-side power consumption is greater than that of a field-effect transistor (FET), which switches to the on state without current flowing through its gate. Based on this characteristic, for power saving purposes, an FET, which switches to the on state without current flowing through its gate, is used instead of a transistor that consumes power by having base current flowing through it in the on state.

[0018] Figure 2This describes a startup circuit 93 that uses a start switch 94 to switch a semiconductor switching element, specifically a FET, on and off. The startup circuit 93 connects the start switch 94 between the gate of the input FET 95 and the ground line 99. Pressing the start switch 94 activates the FET, switching it from on to off and outputting a start signal. Because the startup circuit 93 switches the input FET 95 to off when the start switch 94 is on, the input FET 95 remains on in the normal state when the start switch 94 is not pressed. In the on state, as shown by arrow A, drain current flows from the drain to the source of the input FET 95, and as shown by arrow B, bias current flows from the power supply line 98 to the ground line 99 through the bias resistor 97. The drain current can be reduced by increasing the resistance of the load resistor 96, and the bias current of the bias resistor 97 can be reduced by increasing the resistance of the bias resistor 97. However, if the resistances of the load resistor 96 and the bias resistor 97 are too large, they are easily affected by noise and cannot guarantee stable operation.

[0019] The power supply device according to the first embodiment of the present invention Figure 1 The startup circuit 3 shown uses an input transistor 5, which is connected to the startup switch 4 and becomes ON when current flows through its base, as the semiconductor switching element. This startup circuit 3 replaces the FET with the input transistor 5, reducing bias current and thus cutting unnecessary power consumption.

[0020] The input transistor is a current amplification device; the product of the base current and the current amplification rate is the collector current. Therefore, by setting the collector current of the input transistor in the ON state to be the same as the drain current of the input FET, the base current becomes the drain current / current amplification rate, which can be minimized. For example, Figure 2 The startup circuit 93 can set the drain current of the input FET 95 in the ON state to around 30μA to output a startup signal, but sets the input FET to the level of the input transistor 5. Figure 1 The startup circuit 3 can set the collector current of the input transistor 5 to be the same as the current of the input transistor 5. Figure 2 The startup circuit 93 outputs a startup signal with the same 30μA drain current as the input FET95. Simultaneously, in this state, the base current of the input transistor 5 is reduced to the collector current / current amplification ratio. Therefore, using a bipolar transistor with a current amplification ratio of 100 in the input transistor 5 can significantly reduce the base current to 30 / 100μA, or 0.3μA. Since the current amplification ratio of bipolar transistors is generally in the range of 100–500, therefore… Figure 1 The startup circuit 3, by replacing the FET with a transistor, can reduce the base current to almost negligible levels. Therefore, Figure 1 The startup circuit 3 sets the collector current of the input transistor 5 to be the same as the current of the input transistor 5. Figure 2 The startup circuit 93 has the same drain current value as the input FET 95, thus reducing the current consumption by about 50%.

[0021] Furthermore, the power supply device described above, by connecting a start switch between the base and emitter of the input transistor, also has the advantage of allowing the start switch to have a low withstand voltage. This is because the transistor keeps the base voltage low, thus allowing a very small base current to flow, determined by the collector current / current amplification ratio, to remain in the ON state. Therefore, a small, low-voltage switch can be used for the start switch, and it also achieves the advantage of being able to place a small start switch in a confined space.

[0022] In the power supply device according to the second embodiment of the present invention, the battery connection circuit includes: a detection circuit that detects at least one of the voltage, temperature and current of the battery cells of the battery module, converts the detected analog signal into a digital signal and outputs it; and a microcomputer that performs calculation processing on the digital signal input from the detection circuit.

[0023] The power supply device is characterized by its battery connection circuit detecting the voltage and current of the battery cells that make up the battery module, and further detecting the temperature, thereby preventing overcharging and over-discharging of the battery cells, and detecting the battery temperature to ensure safe charging and discharging.

[0024] In the power supply device according to the third embodiment of the present invention, the circuit structure of the FET output circuit can be configured as follows: a first FET, whose gate is connected to the input transistor, switches the input transistor from on to off, and from off to on; and a second FET, whose gate is connected to the first FET, switches the first FET from off to on, and from off to on, switches the second FET from off to on, and outputs a start signal to the battery connection circuit.

[0025] In the power supply device according to the fourth embodiment of the present invention, the start switch is configured as a normally off manual switch. Furthermore, in the power supply device according to the fifth embodiment of the present invention, the start switch is configured as a push-button switch that outputs a start signal indicating an on state when pressed.

[0026] In the power supply device according to the sixth embodiment of the present invention, as a start-up circuit having a base resistor, the base resistor is connected to the base of the input transistor and the power supply line, and a base current flows through it to set the input transistor to the on state. The circuit structure is as follows: a start switch is connected between the base of the input transistor and the ground line, and the input transistor is switched from on to off by the on signal of the start switch.

[0027] In the power supply device according to the seventh embodiment of the present invention, as a startup circuit having a first load resistor, the first load resistor is connected to the output side of the input transistor, and the circuit structure is configured as follows: the connection point of the first load resistor and the input transistor is connected to the gate of the first FET, the input transistor is switched from on to off, and the first FET is switched from off to on.

[0028] In the power supply device according to the eighth embodiment of the present invention, the circuit structure can be configured such that the first load resistor is connected to the collector of the input transistor.

[0029] In the power supply device according to the ninth embodiment of the present invention, as a startup circuit having a second load resistor connected to the output side of the first FET, the circuit structure is configured such that the gate of the second FET is connected to the second load resistor, the first FET is switched from off to on, and the second FET is switched from off to on.

[0030] In the power supply device according to the 10th embodiment of the present invention, the circuit structure can be configured such that the second load resistor is connected to the drain of the first FET.

[0031] In the power supply device according to the 11th embodiment of the present invention, the circuit structure can be configured such that a third load resistor connected to the output side of the second FET is provided in the startup circuit, the second FET is switched from off to on, and the third load resistor outputs a startup signal to the battery connection circuit.

[0032] In the power supply device according to the 12th embodiment of the present invention, the third load resistor can be connected to the source of the second FET.

[0033] The present invention will now be described in detail with reference to the accompanying drawings. Furthermore, in the following description, terms indicating specific directions and positions (e.g., "upper," "lower," and other terms including these terms) are used as needed, but their use is merely to facilitate understanding of the invention with reference to the drawings and is not intended to limit the technical scope of the invention. Additionally, the same reference numerals in the various drawings represent the same or equivalent parts or components.

[0034] Furthermore, the embodiments shown below represent specific examples of the technical concept of the present invention and are not intended to limit the invention to these embodiments. Additionally, unless specifically stated otherwise, the dimensions, materials, shapes, and relative arrangements of the constituent components described below are not intended to limit the scope of the invention, but are merely illustrative. Furthermore, the content described in one embodiment or example can be applied to other embodiments or examples. Moreover, the size and positional relationships of the components shown in the accompanying drawings are sometimes exaggerated for clarity of description.

[0035] (Power supply device 100)

[0036] Figure 1 The power supply device 100 includes: a battery module 10 in which multiple rechargeable battery cells 1 are connected in series and in parallel; a battery connection circuit 2 connected to the battery module 10; a start circuit 3 of the battery connection circuit 2; and a start switch 4 connected to the start circuit 3.

[0037] (Battery Module 10)

[0038] The battery module 10 connects multiple battery cells 1 in series or parallel to increase the charge and discharge capacity. The battery module 10 is configured with the voltage and charge / discharge capacity most suitable for the application of the power supply device 100 by adjusting the number of battery cells 1 and the number of series or parallel connections. The power supply device 100 is used in various applications, such as in energy storage devices and vehicle power supplies. In energy storage devices, the output voltage of the battery module 10 is set to, for example, 40V to 100V; in vehicle power supplies, the output voltage is set to 200V to 400V. The battery cells 1 are preferably non-aqueous electrolyte secondary batteries such as lithium-ion or lithium-polymer secondary batteries, which increases the charge and discharge capacity relative to weight and capacity. However, the battery cells 1 are not limited to lithium-ion or lithium-polymer secondary batteries; all other rechargeable secondary batteries currently in use or developed in the future, such as nickel-metal hydride batteries and solid-state batteries, can also be used.

[0039] (Battery connection circuit 2)

[0040] The battery connection circuit 2 includes: a detection circuit 21 for detecting the state of the battery module 10, i.e., battery information; and a microcomputer 22 for processing the digital signals output from the detection circuit 21. The battery information detected by the detection circuit 21 includes, for example, the voltage and temperature of the battery cells 1 constituting the battery module 10, and the current of the battery module 10. The detection circuit 21 converts this battery information into analog signals. The detection circuit 21 converts the detected analog signals into digital signals and outputs them to an external control circuit (not shown). In the power supply device 100, the battery connection circuit 2 detects the voltage and temperature of the battery cells 1, and further detects the current of the battery module 10. The power supply device 100 outputs battery information to an external control circuit, which controls the charging and discharging of the battery module 10. This power supply device 100 can charge and discharge the battery module 10 while preventing overcharging and over-discharging of the battery cells 1. Furthermore, the power supply device 100, which includes a detection circuit 21 for detecting the temperature of the battery cells 1, is advantageous in that it maintains the temperature of the battery cells 1 at a set temperature, thereby enabling safe charging and discharging. However, the power supply device 100 described above does not determine the battery information detected by the battery connection circuit 2 as voltage, temperature, or current. For example, it can also detect the remaining capacity of each battery cell 1 as battery information and output it to the outside.

[0041] Although not shown in the figure, the voltage and current detection circuit 21 includes a voltage detection circuit for detecting the voltage of the battery cells 1 constituting the battery module 10, a temperature detection circuit for detecting the temperature of a specific battery cell 1, a current detection circuit for detecting the charging and discharging current of the battery module 10, and an A / D converter for converting the analog signals detected by these detection circuits into digital signals. Furthermore, the power supply device 100 of the present invention may not specify the circuit structure of the detection circuit 21 of the battery connection circuit 2, for example, it may be configured as a detection circuit for detecting other parameters of the battery module 10.

[0042] The microcomputer 22 processes the digital signals input from the detection circuit 21. The microcomputer 22 compares the detected voltage of the battery cell 1 with the minimum and maximum voltages, and outputs a signal determining the maximum charging / discharging current of the battery module 10 to the main control circuit (not shown). Alternatively, it calculates the remaining capacity of the battery module 10 and battery cell 1 based on their voltage and current, and outputs the remaining capacity to an external control circuit. Furthermore, it can illuminate an LED to display the remaining battery capacity.

[0043] Battery connection circuit 2 detects a set period of inactivity during charging / discharging, or detects external signals, and enters a low-power mode to suppress unnecessary power consumption. If a start signal is input from start circuit 3 while in low-power mode, battery connection circuit 2 restarts and returns to its operating state. For example, battery connection circuit 2 can be started from a shutdown state by a trigger signal input from start circuit 3. Battery connection circuit 2 sets both detection circuit 21 and microcomputer 22 to low-power mode to reduce unnecessary power consumption. However, battery connection circuit 2 can also set only one of detection circuit 21 or microcomputer 22 to low-power mode to reduce power consumption.

[0044] In low-power mode, detection circuit 21 stops the power supply from battery module 10, and microcomputer 22 switches to a power-off state, a dormant state, or a hibernation state. In this specification, "low-power mode" refers to any state that reduces power consumption compared to normal operation, and does not necessarily have to be defined as a power-off state, a dormant state, or a hibernation state. Battery connection circuit 2, which sets both detection circuit 21 and microcomputer 22 to low-power mode, inputs a start signal from startup circuit 3 to detection circuit 21 to start it, and outputs a start signal from the started detection circuit 21 to microcomputer 22 to start it. However, battery connection circuit 2 can also input a start signal from startup circuit 3 to both detection circuit 21 and microcomputer 22 to restart them.

[0045] (Start-up circuit 3)

[0046] The startup circuit 3 restarts the battery connection circuit 2 from the low-power mode by receiving an on / off signal from the startup switch 4, thereby switching it to the operating mode. The startup circuit 3 includes: an input transistor 5 whose base is connected to the ground line 19 via the startup switch 4; and a FET output circuit 6 that receives a [High] or [Low] signal from the input transistor 5 and outputs a startup signal. The FET output circuit 6 outputs the startup signal at a timing point when the input transistor 5 switches from on to off.

[0047] (Start switch 4)

[0048] The start switch 4 is a normally closed manual switch, which can be used as a push-button switch that becomes closed when the button is pressed. However, the start switch 4 can also replace the push-button switch and be used with any other switch that can be operated by the user to switch between on and off states, such as a proximity switch.

[0049] (Input transistor 5)

[0050] Input transistor 5 is a bipolar transistor that outputs a "low" signal when the start switch 4 is pressed. The start switch 4 is connected between the base and emitter of input transistor 5. This input transistor 5 switches to an off state where no base current flows by connecting its base and emitter via the on-state start switch 4. Figure 1 The startup circuit 3 connects a base resistor 14 between the base and collector of the input transistor 5. When the startup switch 4 is off, the base resistor 14 supplies current from the collector to the base to keep the input transistor 5 in the ON state. The startup switch 4 is a normally open switch; it is in the OFF state when the button is not pressed, keeping the input transistor 5 in the ON state. The base resistor 14 is configured to withstand the base current flowing through it when the startup switch 4 is off, which keeps the input transistor 5 in the ON state.

[0051] Input transistor 5 controls the collector current through its base current. The product of the base current and the current amplification factor is the collector current. The current amplification factor of a typical transistor is in the range of 100 to 500. Therefore, input transistor 5 sets its base current to 1 / 100 to 1 / 500 of its collector current. For example, an input transistor 5 with a collector current of 50 μA to 100 μA and a current amplification factor of 100 sets its base current to 0.5 μA to 1 μA. This input transistor 5 acts as a resistor to set the base current to 0.5 μA to 1 μA, and its collector current is set to 50 μA.

[0052] The input transistor 5 can reduce the base current to 1 / 100 to 1 / 500 of the collector current, which is effective in significantly reducing the power consumption of the startup circuit 3. Since the startup circuit 3 keeps the input transistor 5 in the on state during the low-power mode of the battery connection circuit 2, it is necessary to reduce the power consumption of the input transistor 5 in the on state, thereby reducing the power consumption of the startup circuit 3 during the low-power mode of the battery connection circuit 2. This is because, during the low-power mode of the battery connection circuit 2, the startup circuit 3 consumes power from the battery module 10 as operating power is supplied to the startup circuit 3 from the battery module 10. This is because, during the low-power mode of the battery connection circuit 2, the startup circuit 3 is kept in an operating mode that can output a startup signal to the battery connection circuit 2 by means of a signal from the start switch 4, discharging the battery module 10. However, the low-power mode is a mode set under conditions of long-term inactivity, and the duration of the low-power mode is often quite long. The power consumption of the startup circuit 3 under this timing is due to the fact that, assuming at least cumulative, the total power discharged to the battery module 10 increases.

[0053] Existing Figure 2In the startup circuit 93 shown, in the input FET 95, which remains on in low-power mode, in addition to the drain current flowing between the drain and source, a bias current also flows in the bias resistor 97 that supplies the gate input turn-on voltage to the FET. The bias resistor 97 is composed of the series resistance of a first bias resistor 97A and a second bias resistor 97B, which divide the voltage of the battery module 90 to supply the gate input turn-on voltage. This bias resistor 97 can determine the gate voltage using the resistance ratio of the first bias resistor 97A to the second bias resistor 97B. However, if the resistance of the second bias resistor 97B connected between the gate and the ground line 99 is increased, the probability of the input FET 95 malfunctioning under external noise or other external conditions increases. In particular, the input impedance of the FET gate is quite high, and with a high-resistance bias resistor 97, it is difficult to reliably prevent malfunctions caused by external noise. Since the bias resistor 97 is always connected to both the positive and negative sides of the battery module 90 and carries bias current to discharge the battery module 90, it is extremely important to reduce the bias current in order to reduce unnecessary power consumption in low-power mode.

[0054] exist Figure 1 In the startup circuit 3, the collector current and base current flow through the input transistor 5, which is in the ON state in low-power mode. The collector current of the input transistor 5 is equivalent to... Figure 2 The drain current and base current of the startup circuit 93 are equivalent to Figure 2 The bias current of the startup circuit 93. Figure 2 The startup circuit 93 can achieve stable operation by setting the drain current and bias current to approximately the same current. Therefore, in low power mode, the battery module 90 is continuously discharged by a current twice the drain current. Figure 1 Because the startup circuit 3 can reduce the base current to a negligible value of 1 / 100 to 1 / 500 of the collector current, in low-power mode, the battery module 10 only becomes the collector current, and... Figure 2 Compared to the starting circuit 93, it can reduce unnecessary discharge of the battery module 10 by 50%. As mentioned above, Figure 1 The startup circuit 3 achieves the following outstanding advantages: instead of a FET, an energy-saving element that can switch to the on state without current flowing through its gate, it uses a bipolar transistor that is set to the on state by current flowing through its base, while simultaneously reducing the power consumption of the battery module 10 by 50% in low-power mode. This advantage is achieved by utilizing the unique characteristics of the bipolar transistor that amplifies current to reduce the unnecessary bias current of the bias resistor of the FET, which is difficult to reduce resistance, in order to ensure stable operation of the FET with high input impedance.

[0055] The input transistor 5 is configured to output a "low" signal to the FET output circuit 6 when it is on and a "high" signal when it is off. A first load resistor 11 is connected to its collector, and the connection point 15 between the collector and the first load resistor 11 is connected to the gate of the first FET 7. In this specification, "low" and "high" are based on ground line 19. The first load resistor 11 is configured to provide a collector current of the input transistor 5 in the on state of 20μA to 50μA. When the start switch 4 switches from off to on, the input transistor 5 switches from on to off and outputs a "high" signal to the FET output circuit 6 via the first load resistor 11. The first load resistor 11 divides the total voltage of the battery module 10 through the base resistor 14 of the input transistor 5 in the off state and outputs it to the FET output circuit 6.

[0056] (FET output circuit 6)

[0057] The "high" signal output from the collector of the input transistor 5 is sent to the battery connection circuit 2 via the FET output circuit 6 as a stable "high" start signal. The FET output circuit 6 does not invert the "high" or "low" of the "high" signal input from the input transistor 5, but outputs the "high" signal to the battery connection circuit 2 with low output impedance. The FET output circuit 6 includes: a first FET 7 connected to the output side of the input transistor 5; and a second FET 8 connected to the output side of the first FET 7. In the normal state where the start switch 4 is not pressed, the FET output circuit 6 keeps both the first FET 7 and the second FET 8 in an off state to reduce power consumption. When the start switch 4 is pressed, both become on, and the "high" signal input from the input transistor 5 is output to the battery connection circuit 2. The first FET 7 is an n-channel FET, with its source connected to ground 19, and becomes on by a "high" signal relative to ground 19. The second FET8 is a p-channel FET, with its source connected to the power line 18, which is the positive side of the battery module 10. Therefore, it is turned on by inputting a turn-on voltage to the gate through a "low" signal relative to the ground line 19.

[0058] (1FET7)

[0059] The first FET7 is turned off when a "low" signal is input to its gate from the input transistor 5, and turned on when a "high" signal is input. The first FET7 outputs "high" when off and "low" when on. The input transistor 5 outputs "low" when the start switch 4 is not pressed and "high" when the start switch 4 is pressed. Therefore, the first FET7 outputs "high" when the start switch 4 is not pressed and "low" when the start switch 4 is pressed. The first FET7 connects its gate to the collector of the input transistor 5, its drain to the power supply line 18 of the battery module 10 via the second load resistor 12, and its source to the ground line 19. The second load resistor 12 divides the voltage of the battery module 10 when the first FET7 is on, providing an on-state voltage to the gate of the second FET8. When the first FET7 is off, the second load resistor 12 connects the gate of the second FET8 to the positive side of the battery module 10, i.e., the source of the second FET8, providing an off-state voltage to the gate.

[0060] (2nd FET8)

[0061] The second FET8 is a p-channel FET. Its source is connected to the power line 18, which is the positive side of the battery module 10. Its gate is connected to the intermediate connection point 16 of the second load resistor 12. Its drain is connected to the ground line 19 via the third load resistor 13. The second FET8 is in the ON state when the first FET7 is ON. This is because, in this state, the second load resistor 12 divides the voltage of the power line 18 to provide an ON voltage to the gate of the second FET8. The ON-state second FET8 outputs a "high" signal to the battery connection circuit 2 by dividing the voltage of the power line 18 through the third load resistor 13 connected between the second FET7 and the ground line 19. The second FET8 is in the OFF state when the first FET7 is OFF. This is because the first FET7 disconnects the second load resistor 12 from the ground line 19 and connects the gate of the second FET8 at its source. The second FET8, which is in the off state, disconnects the third load resistor 13 from the positive side of the battery module 10 and sets the voltage of the intermediate connection point 17 of the third load resistor 13 to "low".

[0062] Since the drain current of the first FET7 in the ON state is determined by the resistance of the second load resistor 12, and the drain current of the second FET8 in the ON state is determined by the resistance of the third load resistor 13, the resistance values ​​of the second load resistor 12 and the third load resistor 13 are set to values ​​that ensure the collector current of each FET in the ON state is a set value. If the resistance of the second load resistor 12 is too high, the "high" or "low" signal cannot be stably output to the second FET8; if it is too low, the collector current of the first FET7 will increase, and power consumption will increase. Therefore, the second load resistor 12 is set to minimize current consumption while stably outputting the ON / OFF signal to the second FET8. The resistance of the third load resistor 13 affects the output impedance of the FET output circuit 6. The third load resistor 13 is set to reduce the output impedance of the FET output circuit 6 and to stably output the start signal to the battery connection circuit 2.

[0063] The power supply device 100 restarts the battery connection circuit 2, which is in low-power mode, through the following actions.

[0064] In low-power mode, the battery connection circuit 2 switches to low-power mode when the device is not in use for an extended period to reduce power consumption. In this mode, the start switch 4 is off, the input transistor 5 of the start circuit 3 is on, the first FET 7 is off, and the second FET 8 is off. The input transistor 5, when on, carries collector current, but this current is negligible compared to the base current, thus significantly reducing power consumption. When the first FET 7 and the second FET 8 are off, the drain current is cut off.

[0065] When restarting the battery connection circuit 2, the user presses the start switch 4 to output an on signal to the start circuit 3. The on signal from the start switch 4 connects the base of the input transistor 5 to the ground line 19 (i.e., the emitter), thereby switching the input transistor 5 to the off state. The off-state input transistor 5 inputs an on voltage to the gate of the first FET 7 via the first load resistor 11, switching the first FET 7 to the on state. The on-state first FET 7 connects the second load resistor 12 to the ground line 19, inputting an on voltage to the gate of the second FET 8 from the intermediate connection point 16 of the second load resistor 12, thereby switching it to the on state. The on-state second FET 8 outputs a "high" start signal to the battery connection circuit 2 from the intermediate connection point 17 of the third load resistor 13. The battery connection circuit 2, receiving the "high" start signal, switches from the low-power mode to the operating mode, thus becoming a normal operating state. Figure 1The battery connection circuit 2 includes a detection circuit 21 and a microcomputer 22. The startup circuit 3 outputs a startup signal to the detection circuit 21, and the detection circuit 21 outputs a startup signal to the microcomputer 22 to enable the microcomputer 22 to restart from the low power mode.

[0066] Industrial availability

[0067] The power supply device of the present invention can be effectively used in devices that reduce power consumption when not in use, and can be restarted by pressing the start switch when in use.

[0068] Explanation of reference numerals in the attached figures

[0069] 100… power supply device

[0070] 1… Battery cell

[0071] 2…Battery connection circuit

[0072] 3…Startup circuit

[0073] 4…Start switch

[0074] 5…Input transistor

[0075] 6…FET output circuit

[0076] 7…1st FET

[0077] 8…2ndFET

[0078] 10… Battery Module

[0079] 11…First load resistor

[0080] 12…Second load resistor

[0081] 13…3rd load resistor

[0082] 14…base resistor

[0083] 15…Connection Point

[0084] 16…Intermediate connection point

[0085] 17…Intermediate connection point

[0086] 18… power cord

[0087] 19…Grounding wire

[0088] 21…Detection Circuit

[0089] 22…microcomputer

[0090] 90… Battery Module

[0091] 92…Battery connection circuit

[0092] 93…Startup Circuit

[0093] 94…Start Switch

[0094] 95…Input FET

[0095] 96…load resistance

[0096] 97… Bias resistor

[0097] 97A…First bias resistor

[0098] 97B…Second Bias Resistor

[0099] 98… power cord

[0100] 99…grounding wire

Claims

1. A power supply device, comprising: The battery module has multiple rechargeable battery cells; A battery connection circuit, connected to the battery module, has a low-power mode switching function; The startup circuit activates the battery connection circuit; and A start switch is connected to the start circuit and outputs a start signal. The startup circuit includes: An input transistor is connected to a start switch between its base and emitter, and is switched to an off state by an on signal from the start switch; and The FET output circuit is connected to the output side of the input transistor. It outputs a start signal to the battery connection circuit, which is in a low-power state, by switching the input transistor from on to off. The FET output circuit includes: The first FET has its gate connected to the input transistor, and is switched from on to off and from off to on by the input transistor; and The second FET connects its gate to the first FET, and switches from off to on via the first FET. The battery connection circuit is started by outputting a start signal to the battery connection circuit through the second FET switching from off to on.

2. The power supply device according to claim 1, wherein, The battery connection circuit includes: The detection circuit detects at least one of the voltage, temperature, and current of the battery cells of the battery module, converts the detected analog signal into a digital signal, and outputs it. and A microcomputer processes the digital signals input from the detection circuit.

3. The power supply device according to claim 1 or 2, wherein, The start switch is a normally off manual switch.

4. The power supply device according to claim 3, wherein, The start switch is a push-button switch that outputs a start signal when pressed to indicate an on state.

5. The power supply device according to claim 1 or 2, wherein, The startup circuit includes a base resistor connected to the base of the input transistor and the power supply line, through which a base current flows to turn on the input transistor. The start switch is connected between the base of the input transistor and the ground line, and the input transistor is switched from on to off by the on signal of the start switch.

6. The power supply device according to claim 1, wherein, The startup circuit includes a first load resistor connected to the output side of the input transistor. The connection point between the first load resistor and the input transistor is connected to the gate of the first FET. The first FET is switched from off to on by the input transistor switching from on to off.

7. The power supply device according to claim 6, wherein, The first load resistor is connected to the collector of the input transistor.

8. The power supply device according to any one of claims 1, 6 to 7, wherein, The startup circuit includes a second load resistor connected to the output side of the first FET. The gate of the second FET is connected to the second load resistor, and the second FET is switched from off to on by the first FET switching from off to on.

9. The power supply device according to claim 8, wherein, The second load resistor is connected to the drain of the first FET.

10. The power supply device according to any one of claims 1, 6 to 7, wherein, The startup circuit includes a third load resistor, which is connected to the output side of the second FET. By switching the second FET from off to on, the third load resistor outputs a start signal to the battery connection circuit.

11. The power supply device according to claim 10, wherein, The third load resistor is connected to the source of the second FET.

12. The power supply device according to claim 1 or 2, wherein, The battery connection circuit is started from the power-off state by a trigger signal input from the startup circuit.

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