CN104333113B - A kind of power circuit - Google Patents

Abstract

The invention relates to a power supply circuit, comprising a first power supply unit, a second power supply unit, a switch unit, and a control unit. The first power supply unit is connected to the second power supply unit through the switch unit; the control unit is connected to the switch unit for controlling the second The power supply unit connects or disconnects the first power supply unit in a set state. The present invention provides two auxiliary power supplies, the first power supply unit: supplying power to circuits that require electric energy in any case, the second power supply unit: supplying power to circuits that do not need electric energy in some cases, the first power supply and the second power supply pass through The switch unit is connected, and the control unit controls and connects the switch unit, which realizes the purpose of not supplying power to circuits that do not need electric energy in some cases, greatly reduces the use of electric energy, and saves energy.

Description

a power circuit

technical field

The invention relates to a power circuit.

Background technique

The main power supply of the charger is used to charge the charging object, and the auxiliary power supply is connected to the auxiliary circuit of the charger, such as internal sampling circuit, drive circuit, fan circuit, single-chip microcomputer and communication circuit, external sampling circuit, input and output protection circuit, internal protection Circuits, etc. These auxiliary circuits complete various auxiliary controls of the charger, as shown in Figure 1 is a block diagram of the auxiliary power supply connection. Initially, there was only one auxiliary power supply for the charger, which supplied power for all auxiliary circuits, but the charger may often be in a standby state due to the nature of its work.

When the charger is in the standby state, some auxiliary circuits are no longer in working state, so there is no need to provide them with power. But at present, the auxiliary power supply of the charger is to supply power to all auxiliary circuits, and it is impossible to supply power to some auxiliary circuits alone, which causes a lot of waste of electric energy.

Contents of the invention

The purpose of the present invention is to provide a power selection control circuit to solve the problem that the non-working circuits still consume electric energy in the standby state.

In order to achieve the above object, the solution of the present invention includes a power supply circuit, including a first power supply unit, a second power supply unit, a switch unit, and a control unit. The first power supply unit is connected to the second power supply unit through the switch unit; the control unit controls the connection switch The unit is used to control the second power supply unit to connect or disconnect the first power supply unit in a set state.

Further, the power supply circuit also includes a charging unit, the first power supply unit is connected to the second power supply unit through the charging unit, and the charging unit is used to provide a charging circuit between the first power supply unit and the second power supply unit; the control unit controls the connection of the charging unit, Used to control the opening and closing of the charging unit.

Further, the power supply circuit also includes a feedback unit, which is used to detect the voltage of the second power supply unit. When the voltage of the second power supply unit exceeds a preset value, the feedback unit turns on the switch unit through the control unit, so that the second power supply unit is directly connected to the first power supply unit.

Further, the switch unit is a relay RY1; the second power supply unit includes a charging capacitor C1; the charging unit includes a resistor R4 in series and a transistor Q2, and the base of the transistor Q2 is used to connect the control unit; the feedback unit includes a resistor R8 and a resistor R9. One end of the series branch is connected to the charging capacitor C1, the other end of the series branch is connected to the control unit, and the voltage dividing point between the resistors R8 and R9 is connected to the control unit.

The control unit includes a voltage regulator U1 and a voltage regulator U2, the other end of the series branch is connected to the anodes of the voltage regulator U1 and the voltage regulator U2, and the voltage dividing point between the resistor R8 and the resistor R9 is connected to the voltage regulator U2 through a diode D1 The reference terminal of the resistor R8 and the resistor R9 are connected to the reference terminal of the voltage regulator U1 at the same time, the input terminal of the level signal CTR is connected to the reference terminal of the voltage regulator U2, and the cathode control of the voltage regulator U2 is connected to the triode Q2; the cathode of the regulator U1 is connected to the triode Q1, which is connected in series with the control coil of the relay RY1, and the first power supply unit is connected to the charging capacitor C1 through the normally open contact of the relay RY1.

The present invention provides two auxiliary power supplies, the first power supply unit: supply power to circuits or components that require electric energy under any circumstances, the second power supply unit: supply power to circuits or components that do not need electric energy in some cases, the first power supply unit It is connected with the second power supply unit through the switch unit, and the control unit controls the connected switch unit. By controlling the switch unit to be turned on and off, the purpose of the second power supply unit being able to provide electric energy or not be able to provide electric energy under certain conditions is realized, which greatly improves the The use of electric energy is reduced and energy is saved.

Description of drawings

Fig. 1 is a prior art auxiliary power connection block diagram;

Fig. 2 is a connection block diagram of the auxiliary power supply of the present invention;

Fig. 3 is simple control block diagram one of the present invention;

Fig. 4 is simple control block diagram two of the present invention;

Fig. 5 is a schematic diagram of the detailed control circuit of the present invention.

detailed description

The present invention will be described in further detail below in conjunction with the accompanying drawings.

A power supply circuit, comprising a first power supply unit, a second power supply unit, a switch unit, and a control unit, the first power supply unit is connected to the second power supply unit through the switch unit; the control unit is connected to the switch unit for controlling the second power supply unit In the setting state, the first power supply unit is connected or disconnected.

Based on the above technical solutions and in conjunction with the accompanying drawings, the following specific implementation is given.

The power supply circuit provided by the present invention is used for reducing the standby power consumption of a charger as an example.

When the charger is in the standby state, some auxiliary circuits do not work, so there is no need to provide power to it. Based on the above principles, two auxiliary power supplies are provided, which are: the first power supply unit and the second power supply unit. The first power supply unit is connected to the control circuit that needs electric energy in any state of the charger, and the second power supply unit is connected to the charger in the standby state. If it does not work, there is no need for a drive circuit that provides power to it. as shown in picture 2.

The power supply circuit for reducing the standby power consumption of the charger includes a first power supply unit, a second power supply unit, a switch unit, and a control unit, the first power supply unit is connected to the second power supply unit through the switch unit; the control unit is connected to the switch unit by controlling It is used to control the second power supply unit to connect or disconnect the first power supply unit when it is in the set state, as shown in FIG. 3 .

Further, as shown in Figure 4, the power supply circuit also includes a charging unit, the first power supply unit is connected to the second power supply unit through the charging unit, and the charging unit is used to provide a charging circuit between the first power supply unit and the second power supply unit; The unit control is connected to the charging unit, and is used to control the opening and disconnection of the charging unit. The power supply circuit also includes a feedback unit, which is used to detect the voltage of the second power supply unit. When the voltage of the second power supply unit exceeds a preset value, the feedback unit turns on the switch unit through the control unit, so that the second power supply unit is directly connected to the first power supply. unit.

The switch unit is a relay RY1; the second power supply unit includes a charging capacitor C1; the charging unit includes a resistor R4 connected in series and a transistor Q2, and the base of the transistor Q2 is used to connect to the control unit; the feedback unit includes a series branch composed of a resistor R8 and a resistor R9 One end of the series branch is connected to the charging capacitor C1, the other end of the series branch is connected to the control unit, and the voltage dividing point between the resistors R8 and R9 is connected to the control unit.

The control unit includes a voltage regulator U1 and a voltage regulator U2, the other end of the series branch is connected to the anodes of the voltage regulator U1 and the voltage regulator U2, and the voltage dividing point between the resistor R8 and the resistor R9 is connected to the voltage regulator U2 through a diode D1 The reference terminal of the resistor R8 and the resistor R9 are connected to the reference terminal of the voltage regulator U1 at the same time, the input terminal of the level signal CTR is connected to the reference terminal of the voltage regulator U2, and the cathode control of the voltage regulator U2 is connected to the triode Q2; the cathode of the regulator U1 is connected to the triode Q1, which is connected in series with the control coil of the relay RY1, and the first power supply unit is connected to the charging capacitor C1 through the normally open contact of the relay RY1.

The specific circuit diagram is shown in Figure 4, and the specific connections of the circuit diagram are:

One end of the resistor R1 is connected to the first power supply unit VCC and the emitter of the transistor Q1, the other end of the resistor R1 is connected to one end of the resistor R2 and the cathode of the voltage regulator U1, the other end of the resistor R2 is connected to the base of the transistor Q1, and the transistor Q1 The collector is connected to the coil of the relay RY1 through the resistor R3, the anode of the voltage regulator U1 is connected to the anode of the voltage regulator U2 and one end of the resistor R9, and the other end of the resistor R9 is connected to the reference terminal of the voltage regulator, the positive pole of the diode D1, and the resistor R8 One end of the diode D1, the other end of the diode D1 is connected to one end of the resistor R7 and the input end of the level signal CTR, the other end of the resistor R7 is connected to the reference end of the voltage regulator, and the other end of the resistor R8 is connected to the second power supply unit - capacitor C1 and The collector of the transistor Q2, the other end of the capacitor C1 is grounded, the base of the transistor Q2 is connected to one end of the resistor R6, the other end of the resistor R6 is connected to one end of the resistor R5 and the cathode of the regulator U2, and the other end of the resistor R5 is connected to the resistor R4 One end of the resistor R4 is connected to the emitter of the transistor Q2, the other end of the resistor R4 is connected to VCC and one end of the normally open contact of the relay RY1, and the capacitor C1 is connected to the other end of the normally open contact of the relay RY1.

When the charger is on standby, the level signal CTR input is low level (less than 2.5V), the cathode of U2 is high level, the CE of Q2 is not turned on, and at the same time, CTR pulls down the reference terminal level of U1 through diode D1 , so that the cathode of U1 is high, the CE of Q1 is not conducting, there is no voltage in the coil of the relay, and the normally open contact is not closed, so there is no voltage on the capacitor C1, and the potential of VCC_1 is 0. Capacitor C1 cannot provide electric energy to the circuit connected to it, so as to achieve the purpose of saving electric energy.

When the charger changes from standby to charging state, the CTR input changes from low level to high level (greater than 2.5V), the cathode of U2 is low level, the CE of Q2 is turned on, and VCC charges capacitor C1 through resistor R4. When the voltage value of C1 is close to VCC, it can also be said that when the voltage value of C1 is a certain set value, the sampling signal VS level obtained by dividing the voltage by resistors R8 and R9 reaches 2.5V, and the cathode of U1 is low voltage. Ping, the CE of the transistor Q1 is turned on, the coil of the relay RY1 is energized, the relay contacts are closed, the capacitor C1 and VCC are connected through the relay contacts, and VCC continues to charge the capacitor C1, and finally the voltages of the two are consistent. Capacitor C1 provides power to the circuit to which it is connected.

When the charger is charging the battery: CTR input is high level, the contact of relay RY1 is closed, and the voltage value of capacitor C1 and VCC is equal. Capacitor C1 provides power to the circuit to which it is connected.

When the charger changes from charging to standby: CTR input changes from high level to low level, U2 cathode changes from low level to high level, CE of Q2 is not turned on, and at the same time, CTR pulls the reference terminal of U1 through diode D1 To low level, the cathode of U1 is high level, the CE of Q1 is not conducting, the relay coil is de-energized, the contact is disconnected, the capacitor C1 is discharged to the ground, and the voltage value of the capacitor C1 drops to 0. Capacitor C1 cannot provide power to the circuit to which it is connected.

Specific embodiments have been given above, but the present invention is not limited to the described embodiments. The basic idea of the present invention lies in the above-mentioned basic scheme. For those of ordinary skill in the art, according to the teaching of the present invention, it does not need to spend creative labor to design various deformation models, formulas, and parameters. Changes, modifications, substitutions and variations to the implementations without departing from the principle and spirit of the present invention still fall within the protection scope of the present invention.

Claims (4)

1. a kind of power circuit, it is characterised in that the power circuit includes the first power subsystem, second source unit, switch Unit, control unit, first power subsystem connect second source unit by switch element；Control unit control connection institute Switch element is stated, for controlling the second source unit to be connected in the state of setting or disconnecting the first power subsystem；It is described Second source unit includes a charging capacitor C1；

The power circuit also includes a feedback unit, for detecting the voltage of second source unit, when second source unit Voltage when exceeding preset value, feedback unit opens the switch element by control unit, makes the second source unit straight Lead to first power subsystem in succession；

The feedback unit includes the series arm that resistance R8 and resistance R9 is formed, series arm one end connection charging capacitor C1, series arm other end connection control unit, the dividing point connection control unit between resistance R8 and resistance R9.

2. power circuit according to claim 1, it is characterised in that the power circuit also includes charhing unit, and first Power subsystem connects second source unit by charhing unit, and the charhing unit is used to provide the first power subsystem and the second electricity Charge circuit between source unit；Described control unit control connects the charhing unit, for controlling the open-minded of charhing unit With disconnection.

3. power circuit according to claim 2, it is characterised in that the switch element is relay RY1；The charging Resistance R4 and triode Q2, the triode Q2 that unit includes series connection base stage are used to connect control unit.

4. power circuit according to claim 3, it is characterised in that described control unit includes voltage-stablizer U1 and voltage-stablizer U2, the anode of the series arm other end connection voltage-stablizer U1 and voltage-stablizer U2, point between the resistance R8 and resistance R9 For pressure point by diode D1 connection voltage-stablizers U2 reference edge, the dividing point between resistance R8 and resistance R9 connects voltage-stablizer simultaneously U1 reference edge, level signal CTR input connection voltage-stablizer U2 reference edge, voltage-stablizer U2 cathodic control connect three poles Pipe Q2；Voltage-stablizer U1 cathodic control connecting triode Q1, triode Q1 connects with the control coil of the relay RY1, the One power subsystem connects charging capacitor C1 by relay RY1 normally opened contact.