A high current discharge circuit for battery-powered equipment

Abstract

The present invention discloses a high-current discharge circuit for a battery-powered device, which effectively alleviates the pressure on battery capacity and enables the battery to achieve a high-current discharge function under low-temperature conditions. The circuit includes a discharge control switch 6N1, an anti-capacitor reverse charge switch 6N2, a discharge control switch 6N3, a charge control switch 6N4, and an energy storage capacitor; the output end of the control circuit is respectively connected to the gate of the N-type transistor of each control switch; the source (pin 2) of the N-type transistor of the discharge control switch 6N1 is connected to the power supply, and the drain of the P-type transistor is connected to the high-current load; the source of the P-type transistor of the charge control switch 6N4 is connected to the power supply, and the drain is connected to the energy storage capacitor; the drain of the P-type transistor of the anti-capacitor reverse charge switch 6N2 is connected to the energy storage capacitor, and the source is connected to the source of the P-type transistor of the discharge control switch 6N3; the drain of the P-type transistor of the discharge control switch 6N3 is connected to the high-current load and is also connected to the drain of the P-type transistor of the discharge control switch 6N1.

Description

Technical Field

[0001] The present invention relates to the field of electronics and communications technology, and in particular to a high-current discharge circuit for battery-powered equipment. Background Art

[0002] With the continuous development of communication equipment, the application of handheld devices is increasing, and the functions of handheld devices are becoming more and more powerful. The application of large current consumption in various applications puts more and more stringent requirements on the power supply of handheld devices.

[0003] Handheld devices are typically powered by batteries. Limited by battery capacity and size, batteries are often designed for maximum capacity within a given volume, which often limits their high-current discharge capabilities. Currently, most secondary batteries used in handheld devices are lithium-ion batteries, while primary batteries include lithium-ion batteries, lithium-carbon-fluoride batteries, lithium-manganese batteries, and lithium-sulfur-dioxide batteries. The high-current discharge capability of these batteries is related to their capacity, ranging from a low of 0.1C to a high of 2C. While these batteries can generally meet high-current discharge requirements at room temperature, they are insufficient at low temperatures due to reduced battery capacity, limiting the operating temperature range of handheld devices. Summary of the Invention

[0004] In response to the problems existing in the prior art, the purpose of the present invention is to provide a high-current discharge circuit for a battery-powered device, which can effectively alleviate the battery capacity pressure, enable the battery to achieve high-current discharge function under low temperature conditions, expand the operating temperature of the handheld device, and extend the working time of the handheld device.

[0005] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions to achieve it.

[0006] A high-current discharge circuit for a battery-powered device includes a discharge control switch 6N1, an anti-capacitor reverse charge switch 6N2, a discharge control switch 6N3, a charge control switch 6N4, and an energy storage capacitor;

[0007] The discharge control switch 6N1 is connected to a control circuit, the output end of which is connected to the gate (pin 1) of the N-type transistor of the discharge control switch 6N1 for controlling the input voltage of the gate of the N-type transistor; the source (pin 2) of the P-type transistor of the discharge control switch 6N1 is connected to a power supply, the gate (pin 3) of the P-type transistor of the discharge control switch 6N1 is connected to a power supply via a resistor, the drain (pin 6) of the N-type transistor of the discharge control switch 6N1 is connected to the gate (pin 3) of the P-type transistor via a resistor, and the drain (pin 4) of the P-type transistor of the discharge control switch 6N1 is connected to a high-current load;

[0008] The gate electrode (pin 1) of the N-type transistor of the charging control switch 6N4 is connected to the output end of the control circuit, the source electrode (pin 2) of the P-type transistor of the charging control switch 6N4 is connected to the power supply, the gate electrode (pin 3) of the P-type transistor of the charging control switch 6N4 is connected to the power supply via a resistor, the drain electrode (pin 6) of the N-type transistor of the charging control switch 6N4 is connected to the gate electrode (pin 3) of the P-type transistor via a resistor, and the drain electrode (pin 4) of the P-type transistor of the charging control switch 6N4 is connected to the energy storage capacitor;

[0009] The gate electrode (pin 1) of the N-type transistor of the anti-capacitor reverse charge switch 6N2 is connected to the output end of the control circuit, the drain electrode (pin 4) of the P-type transistor of the anti-capacitor reverse charge switch 6N2 is connected to the energy storage capacitor, the source electrode (pin 2) of the P-type transistor of the anti-capacitor reverse charge switch 6N2 is connected to the source electrode (pin 2) of the P-type transistor of the discharge control switch 6N3, the gate electrode (pin 3) of the P-type transistor of the anti-capacitor reverse charge switch 6N2 is connected to the energy storage capacitor via a resistor, and the drain electrode (pin 6) of the N-type transistor of the anti-capacitor reverse charge switch 6N2 is connected to the gate electrode (pin 3) of the P-type transistor via a resistor;

[0010] The gate (pin 1) of the N-type transistor of the discharge control switch 6N3 is connected to the output end of the control circuit, the gate (pin 3) of the P-type transistor of the discharge control switch 6N3 is connected to the source (pin 2) of the P-type transistor of the anti-capacitor reverse charging switch 6N2 through a resistor, the drain (pin 6) of the N-type transistor of the anti-capacitor reverse charging switch 6N2 is connected to the gate (pin 3) of the P-type transistor through a resistor, and the drain (pin 4) of the P-type transistor of the discharge control switch 6N3 is connected to a high current load; the drain (pin 4) of the P-type transistor of the discharge control switch 6N3 is also connected to the drain (pin 4) of the P-type transistor of the discharge control switch 6N1.

[0011] The characteristics and further improvements of the technical solution of the present invention are:

[0012] The discharge control switch 6N1 , the capacitor reverse charge prevention switch 6N2 , the discharge control switch 6N3 , and the charge control switch 6N4 are MOS field effect transistors IRF5851 respectively.

[0013] A plurality of resistors connected in parallel are connected in series between the fourth pin of the charging control switch 6N4 and the energy storage capacitor.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] The high-current discharge circuit of a battery-powered device provided by the present invention effectively alleviates battery capacity pressure, enabling the battery to achieve high-current discharge function under low-temperature conditions. At the same time, the battery capacity during low-current discharge is larger than that during high-current discharge. Applying the high-current discharge circuit of the present invention to a handheld device extends the operating temperature of the handheld device and prolongs the operating time of the handheld device. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 A circuit diagram of a high-current discharge circuit of a battery-powered device according to the present invention;

[0018] Figure 2 This is the schematic diagram of the MOS field effect transistor IRF5851. DETAILED DESCRIPTION

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0020] To address the problems in the prior art, an analysis of the high-current application state of handheld devices revealed that high-current application states of handheld devices often involve high operating currents for short periods of time. Based on these application characteristics, the present invention employs energy storage capacitors for energy storage, relying on the energy storage capacitors and batteries to jointly complete high-current discharge. The solution proposed by the present invention first requires determining the discharge time and discharge current for high-current discharge, and also the current and charging time for the energy storage capacitors. Combined with the handheld device's own control circuitry, the energy storage capacitors are charged before high-current discharge, and the energy storage capacitors and batteries are discharged together during high-current discharge.

[0021] The charging and discharging of energy storage capacitors vary in duration and current, so they should be charged and discharged in two ways: charging with a long, low current, and discharging with a short, high current. Power is supplied by both battery power and energy storage capacitor discharge. Conventional power is supplied by the battery, while high-current discharge is combined with energy storage capacitor discharge on top of the battery power supply. Because the battery power and energy storage discharge paths are short-circuited at the high-current discharge unit port, isolation is required. A voting circuit with two diodes can accomplish this function, but the diodes consume too much power to be practical. Therefore, an anti-reverse charge switch is added after the energy storage capacitor to ensure that the energy storage capacitor is not charged when the battery is the only power source.

[0022] Specifically, refer to Figure 1 , the present invention provides a high-current discharge circuit for a battery-powered device, comprising a discharge control switch 6N1, an anti-capacitor reverse charge switch 6N2, a discharge control switch 6N3, a charge control switch 6N4 and an energy storage capacitor;

[0023] The discharge control switch 6N1 is connected to a control circuit, the output end of which is connected to the gate (pin 1) of the N-type transistor of the discharge control switch 6N1 for controlling the input voltage of the gate of the N-type transistor; the source (pin 2) of the P-type transistor of the discharge control switch 6N1 is connected to a power supply, the gate (pin 3) of the P-type transistor of the discharge control switch 6N1 is connected to a power supply via a resistor, the drain (pin 6) of the N-type transistor of the discharge control switch 6N1 is connected to the gate (pin 3) of the P-type transistor via a resistor, and the drain (pin 4) of the P-type transistor of the discharge control switch 6N1 is connected to a high-current load;

[0024] The gate electrode (pin 1) of the N-type transistor of the charging control switch 6N4 is connected to the output end of the control circuit, the source electrode (pin 2) of the P-type transistor of the charging control switch 6N4 is connected to the power supply, the gate electrode (pin 3) of the P-type transistor of the charging control switch 6N4 is connected to the power supply via a resistor, the drain electrode (pin 6) of the N-type transistor of the charging control switch 6N4 is connected to the gate electrode (pin 3) of the P-type transistor via a resistor, and the drain electrode (pin 4) of the P-type transistor of the charging control switch 6N4 is connected to the energy storage capacitor;

[0025] The gate electrode (pin 1) of the N-type transistor of the anti-capacitor reverse charge switch 6N2 is connected to the output end of the control circuit, the drain electrode (pin 4) of the P-type transistor of the anti-capacitor reverse charge switch 6N2 is connected to the energy storage capacitor, the source electrode (pin 2) of the P-type transistor of the anti-capacitor reverse charge switch 6N2 is connected to the source electrode (pin 2) of the P-type transistor of the discharge control switch 6N3, the gate electrode (pin 3) of the P-type transistor of the anti-capacitor reverse charge switch 6N2 is connected to the energy storage capacitor via a resistor, and the drain electrode (pin 6) of the N-type transistor of the anti-capacitor reverse charge switch 6N2 is connected to the gate electrode (pin 3) of the P-type transistor via a resistor;

[0026] The gate (pin 1) of the N-type transistor of the discharge control switch 6N3 is connected to the output end of the control circuit, the gate (pin 3) of the P-type transistor of the discharge control switch 6N3 is connected to the source (pin 2) of the P-type transistor of the anti-capacitor reverse charging switch 6N2 through a resistor, the drain (pin 6) of the N-type transistor of the anti-capacitor reverse charging switch 6N2 is connected to the gate (pin 3) of the P-type transistor through a resistor, and the drain (pin 4) of the P-type transistor of the discharge control switch 6N3 is connected to a large current load.

[0027] The discharge control switch 6N1 , the capacitor reverse charge prevention switch 6N2 , the discharge control switch 6N3 , and the charge control switch 6N4 are each a MOS field effect transistor IRF5851.

[0028] refer to Figure 2 , MOS field effect transistor IRF5851 is a circuit constructed based on the principle that the MOS tube gate controls the on and off of the MOS tube source and drain. It contains two types of transistors, N-channel and P-channel. The source of the N-channel transistor is grounded (pin 5), and it will be turned on when the gate (pin 1) voltage is greater than a certain value, and the drain (pin 6) is connected to the power supply; the source of the P-channel transistor is connected to the power supply, and it will be turned on when the gate (pin 3) voltage is lower than the source (pin 2) by a certain voltage; Figure 2 When the input port is connected to a voltage, to ensure the conduction of the P-channel transistor, it is only necessary to apply a voltage to pin 1 to a certain value to turn on the N-channel transistor. Then, pin 3 is grounded and meets the conduction condition of the P-channel transistor, making the entire circuit conductive. Conversely, when the input voltage of pin 1 does not meet the conduction condition of the N-channel transistor, pin 3 is connected to R3 and the input is connected to restore the initial condition, and the entire circuit is disconnected.

[0029] Will Figure 2The input and output ports of the MOS field effect transistor IRF5851 control switch shown are connected in series between the power supply and the load. The output is affected by the control port of the MOS field effect transistor IRF5851 to achieve the function of controlling the on and off of the power supply. Its ground port is connected to the power ground inside the adapter box to achieve the purpose of simplifying the circuit. The wires used in the manufacture of the switch part minimize the impedance in the input and output parts in order to reduce the voltage difference and improve its stability and sensitivity.

[0030] In the above-mentioned high-current discharge circuit, the on-off selection of each switch is completed by the control circuit. This type of switch has the advantages of small on-resistance and fast switching speed.

[0031] 6N2 uses this switch as an anti-capacitor reverse charge switch. When the power is supplied, that is, when the battery is supplied, the voltage reaches pin 2 through pin 4 of 6N3, and the voltage drops by 0.2V. Therefore, the voltage at pin 2 of the anti-capacitor reverse charge switch 6N2 is the power supply voltage minus 0.2V. Because the anti-reverse charge switch is at a low level, the voltage will not reach pin 4 of the anti-capacitor reverse charge switch 6N2. If the anti-reverse charge switch is at a high level at this time, the voltage will reach pin 4 of the anti-capacitor reverse charge switch 6N2, that is, the battery will charge the energy storage capacitor. Because the resistance of this path is small and the capacitance of the energy storage capacitor is large, the charging current is very large. This type of problem should be prevented through a control circuit.

[0032] When the handheld device is used normally, the discharge control switch 6N1 is set to high and the anti-capacitor reverse charging switch 6N2 is set to low. At this time, the high-current load has power, and at the same time, the battery can be prevented from charging the energy storage capacitor. The device operates in a low-current mode; when a large current discharge is required, the control end sets the charging control switch 6N4 to high in advance to charge the energy storage capacitor in advance. When the large current is discharged, the discharge control switch 6N1 is set to high and the anti-capacitor reverse charging switch 6N2 is set to high. At this time, the battery and the energy storage capacitor are discharged at the same time.

[0033] The high-current discharge circuit of a battery-powered device proposed in the present invention can be applied to the high-current discharge requirements of handheld devices, can effectively alleviate the pressure on battery capacity, and can effectively adapt to battery applications in low-temperature environments. At the same time, the battery capacity during low-current discharge is larger than the battery capacity during high-current discharge. Therefore, the high-current discharge circuit of a battery-powered device proposed in the present invention can effectively utilize the battery capacity in practical applications and extend the working time of the handheld device.

[0034] It is worth mentioning that during the operation of the high-current discharge circuit of the battery-powered device proposed in the present invention, attention should be paid to the calculation of the capacity of the energy storage capacitor, the capacitor charging and discharging time should be calculated according to parameters such as the discharge preparation time and the discharge time, the charging current limiting resistor should be reasonably set, and it should be ensured that each resistor and capacitor is in a derated application state, and the capacitor polarity should be correct.

[0035] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A high current discharge circuit for a battery powered device, characterized in that: It includes a discharge control switch 6N1, an anti-capacitor reverse charging switch 6N2, a discharge control switch 6N3, a charge control switch 6N4 and an energy storage capacitor; The discharge control switch 6N1 is connected to a control circuit, the output end of which is connected to pin 1 of the gate of the N-type field effect transistor of the discharge control switch 6N1 for controlling the input voltage of the gate of the N-type field effect transistor; pin 2 of the source of the P-type field effect transistor of the discharge control switch 6N1 is connected to a power supply, pin 3 of the gate of the P-type field effect transistor of the discharge control switch 6N1 is connected to a power supply via a resistor, pin 6 of the drain of the N-type field effect transistor of the discharge control switch 6N1 is connected to pin 3 of the gate of the P-type field effect transistor via a resistor, and pin 4 of the drain of the P-type field effect transistor of the discharge control switch 6N1 is connected to a high current load; Pin 1 of the gate of the N-type field effect transistor of the charging control switch 6N4 is connected to the output end of the control circuit, pin 2 of the source of the P-type field effect transistor of the charging control switch 6N4 is connected to the power supply, pin 3 of the gate of the P-type field effect transistor of the charging control switch 6N4 is connected to the power supply via a resistor, pin 6 of the drain of the N-type field effect transistor of the charging control switch 6N4 is connected to pin 3 of the gate of the P-type field effect transistor via a resistor, and pin 4 of the drain of the P-type field effect transistor of the charging control switch 6N4 is connected to the energy storage capacitor; Pin 1 of the gate of the N-type field effect transistor of the anti-capacitor reverse charge switch 6N2 is connected to the output end of the control circuit, pin 4 of the drain of the P-type field effect transistor of the anti-capacitor reverse charge switch 6N2 is connected to the energy storage capacitor, pin 2 of the source of the P-type field effect transistor of the anti-capacitor reverse charge switch 6N2 is connected to pin 2 of the source of the P-type field effect transistor of the discharge control switch 6N3, and pin 3 of the gate of the P-type field effect transistor of the anti-capacitor reverse charge switch 6N2 is connected to the energy storage capacitor via a resistor; Pin 1 of the gate of the N-type field effect transistor of the discharge control switch 6N3 is connected to the output end of the control circuit, pin 3 of the gate of the P-type field effect transistor of the discharge control switch 6N3 is connected to pin 2 of the source of the P-type field effect transistor of the anti-capacitor reverse charge switch 6N2 via a resistor, pin 6 of the drain of the N-type field effect transistor of the anti-capacitor reverse charge switch 6N2 is connected to pin 3 of the gate of the P-type field effect transistor via a resistor, and pin 4 of the drain of the P-type field effect transistor of the discharge control switch 6N3 is connected to a high current load; pin 4 of the drain of the P-type field effect transistor of the discharge control switch 6N3 is also connected to pin 4 of the drain of the P-type field effect transistor of the discharge control switch 6N1; The discharge control switch 6N1, the anti-capacitor reverse charge switch 6N2, the discharge control switch 6N3, and the charge control switch 6N4 are respectively MOS field effect transistors IRF5851; A plurality of resistors connected in parallel are connected in series between the drain pin 4 of the P-type field effect transistor of the charging control switch 6N4 and the energy storage capacitor.

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