TWI777617B - Charging wake-up circuit - Google Patents

Abstract

A charging wake-up circuit includes a first switch, a second switch, a first resistor, a second resistor, and a third resistor. The first switch has a first terminal for receiving a first voltage, and a control terminal for receiving a second voltage. The second switch has a first terminal coupled to the second terminal of the first switch. The first resistor has a first terminal coupled to the control terminal of the second switch, and a second terminal coupled to the first terminal of the second switch. The second resistor has a first terminal coupled to the second end of the second switch, and a second terminal. The third resistor has a first terminal coupled to the second terminal of the second resistor and a device to provide a control voltage to the device to wake up the device, and a second terminal to receive a third voltage.

Description

Charge wake-up circuit

The present invention relates to a charging wake-up circuit, in particular to a charging wake-up circuit that can provide a control voltage to wake up a device during charging.

After electronic products are produced, they often have to be transported and stored before they can be sold to users. Because the batteries of electronic products do not work during transportation, after production, the batteries must be put into a state with the lowest power consumption in order to save the power consumption of the batteries. This state can be called the ship mode.

When the user wants to start using the electronic product, he has to go through a specific operation to make the electronic product leave the transport mode. Generally speaking, a dedicated input and output (I/O) pin can be set in the control circuit of an electronic product, so that the battery can enter a normal working state through the input and output pin. To the input and output pins, a specific voltage can be applied or a short-circuit contact can be made to wake up the battery of the electronic product.

In addition, these triggering actions often need to be matched with a specific program in the system to enable electronic products. Therefore, it is not only necessary to set additional input and output pins in the electronic product, which makes the system complicated, but also needs to educate the user, which often causes inconvenience to the user.

Embodiments provide a charging wake-up circuit for waking up a device. The charging wake-up circuit includes a first switch, a second switch, a first resistor, a second resistor and a third resistor. The first switch includes a first terminal, a second terminal and a control terminal, wherein the first terminal is used for receiving a first voltage, and the control terminal is used for receiving a second voltage. The second switch includes a first terminal, a second terminal and a control terminal, wherein the first terminal is coupled to the second terminal of the first switch. The first resistor includes a first One end and a second end, wherein the first end is coupled to the control end of the second switch, and the second end is coupled to the first end of the second switch. The second resistor includes a first end and a second end, wherein the first end is coupled to the second end of the second switch. The third resistor includes a first end and a second end, wherein the first end is coupled to the second end of the second resistor and a first end of the device to provide a control voltage to the device, And the second end is used for receiving a third voltage.

100: charging wake-up circuit

Q1, Q2, Q3: switch

R1, R2, R3: Resistors

Vpack, Vbat+, Vbat-, Ven: Voltage

VR: Control Voltage

155: Device

FIG. 1 is a schematic diagram of a charging wake-up circuit coupled to the device in an embodiment.

FIG. 2 is a schematic diagram of the charging wake-up circuit of FIG. 1 coupled to the device in the embodiment.

In order to reduce the complexity of the circuit and improve the convenience of use, the embodiments may provide the following solutions. FIG. 1 is a schematic diagram of a charging wake-up circuit 100 in an embodiment. The wake-up-on-charge circuit 100 can be used to wake up the device 155 . The charging wake-up circuit 100 may include a first switch Q1, a second switch Q2, a third switch Q3, a first resistor R1, a second resistor R2 and a third resistor R3. For example, the charging wake-up circuit 100 may be provided in a battery pack.

Wherein, the charging wake-up circuit 100 of the present invention is suitable for a circuit for enabling a battery module in a vehicle electronic product, but is not limited thereto.

The first switch Q1 may include a first terminal, a second terminal and a control terminal, wherein the first terminal is used for receiving the first voltage Vpack, and the control terminal is used for receiving the second voltage Vbat+. The second switch Q2 may include a first terminal, a second terminal and a control terminal, wherein the first terminal is coupled to the second terminal of the first switch Q1. The third switch Q3 may include a first terminal, a second terminal and a control terminal, wherein the first terminal may be coupled to the control terminal of the second switch Q2, the second terminal may be used for receiving the third voltage Vbat-, and the control terminal may be coupled to The second terminal of the device 155 is connected to receive the fourth voltage Ven.

The first resistor R1 may include a first terminal and a second terminal, wherein the first terminal is coupled to the control terminal of the second switch Q2, and the second terminal is coupled to the first terminal of the second switch Q2. The second resistor R2 may include a first terminal and a second terminal, wherein the first terminal is coupled to the second terminal of the second switch Q2. The third resistor R3 may include a first end and a second end, wherein the first end is coupled to the second end of the second resistor R2 and the first end of the device 155 to provide the control voltage VR to the device 155, and the third resistor The second terminal of R3 is used for receiving the third voltage Vbat-.

FIG. 2 is a schematic diagram of the charging wake-up circuit 100 of FIG. 1 coupled to the device 155 in the embodiment. As shown in FIG. 2 , the first switch Q1 can be a P-type transistor, and the second switch Q2 and the third switch Q3 can be an N-type transistor. The first end of the first switch Q1, the second end of the second switch Q2 and the second end of the third switch Q3 can be sources; the second end of the first switch Q1, the first end of the second switch Q2 and the second end of the third switch Q3 The first terminals of the three switches Q3 can be drain electrodes; and the control terminals of the first switch Q1 , the second switch Q2 and the third switch Q3 can be gate electrodes.

According to an embodiment, the second voltage Vbat+ may be the positive voltage of the battery, the third voltage Vbat- may be the negative voltage of the battery, and the second voltage Vbat+ may be higher than the third voltage Vbat-.

According to the embodiment, the first voltage Vpack can be generated by the commercial power through the transformer; in other words, the first voltage Vpack can be the voltage from the transformer when charging the electronic product.

According to an embodiment, when the first voltage Vpack is higher than the second voltage Vbat+, the first switch Q1 and the second switch Q2 can be turned on, and the control voltage VR can be used to wake up the device 155 to make the device 155 enter the non-transport mode from the shipping mode. For example, the non-transport mode may include a normal mode, a sleep mode, and the like. According to an embodiment, after the device 155 enters the non-transport mode from the transport mode, it may not return to the transport mode.

As shown in Figure 1, when the first voltage Vpack is higher than the second voltage Vbat+, the control voltage VR can be equal to the difference between the first voltage Vpack minus the third voltage Vbat-, multiplied by the third resistor R3, and then divided by the first voltage Vpack minus the third voltage Vbat- The quotient obtained from the sum of the second resistor R2 and the third resistor R3 is shown in the formula eq-1: VR=(Vpack-Vbat-)×[R3/(R2+R3)]......eq-1 ; In other words, when the first voltage Vpack is higher than the second voltage Vbat+, the control voltage VR can It should be divided by the first voltage Vpack through the second resistor R2 and the third resistor R3. Wherein, if the level of the third voltage Vbat- is regarded as zero, the formula eq-1 can be: VR=Vpack×[R3/(R2+R3)].

When the charging wake-up circuit 100 has not woken up the device 155 and the device 155 is still in the transport mode, since the battery has not been charged, the cell voltage of the battery (ie the second voltage Vbat+) is relatively low, so the first voltage Vpack is higher than the second voltage Vbat+. At this time, the external charger can provide a constant voltage (ie, the first voltage Vpack) to supply power to the battery when there is no load. At this time, since the cell voltage of the battery is low, the first switch Q1 can be turned on, so that the external voltage can generate the control voltage VR, so as to wake up the device 155 .

When the device 155 is woken up, it should stop continuing to wake up the device 155 . Therefore, as shown in FIG. 1, the third switch Q3 can be used to drop the control voltage VR when the device 155 is woken up, as described below.

According to the embodiment, when the device 155 is woken up, the device 155 can leave the transport mode, and the device 155 can adjust the level of the fourth voltage Ven, thereby turning on the third switch Q3 and turning off the second switch Q2, so as to reduce the control voltage VR . Thus, when the device 155 is awakened, it can leave the shipping mode without returning to the shipping mode.

For example, when the device 155 has been woken up, the device 155 can control the fourth voltage Ven from a low level to a high level. In this example, when the device 155 has been woken up and the fourth voltage Ven is at a high level, the third switch Q3 can be turned on, so that the control terminal of the second switch Q2 receives the lower third voltage Vbat- through the third switch Q3 was cut off.

According to the embodiment, as the applied voltage increases, in order to separate from the power supply of the main controller, an optocoupler may be used to separate the power supply of the charging wake-up circuit 100 and the main controller to achieve the isolation effect and comply with safety regulations.

The application scenarios of this case are described below by way of example for easy understanding. When the device 155 leaves the factory, the battery capacity is only 30% to 50%, and the battery activity is low to ensure safe transportation. when the user After purchase, the device 155 should be charged before using the device 155 for the first time. Typically, the device 155 should be charged for a predetermined period of time, such as eight hours. By charging the new device 155 with low power, the second voltage Vbat+ gradually rises from a low level to a high level. During this period, the device 155 can be woken up as described above, and the control can be adjusted after the device 155 is woken up. The level of the voltage VR does not continue to wake up the device 155 . The above numerical values are only examples, and the embodiments are not limited thereto.

In one embodiment of the present invention, the in-vehicle electronic product of the present invention can be applied to in-vehicle devices, such as self-driving cars, electric cars, or semi-autonomous cars.

In general, using the charging wake-up circuit 100 provided by the embodiment, the wake-up function can be performed through a necessary charging operation, and no additional input and output pins need to be used to receive a specific voltage or short-circuit contact to wake up the device 155, so the circuit can be reduced. complexity and save input and output pins. In addition, there is no need to perform complicated procedures, so it is possible to avoid educating consumers to perform complicated wake-up operations, thereby improving the convenience in use. In addition, the charging wake-up circuit 100 can also have sufficient isolation, so it can comply with safety regulations. Therefore, a long-standing problem in the field can be effectively dealt with.

The above descriptions are only preferred embodiments of the present invention, and all equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope of the present invention.

100: charging wake-up circuit

Q1, Q2, Q3: switch

R1, R2, R3: Resistors

Vpack, Vbat+, Vbat-, Ven: Voltage

VR: Control Voltage

155: Device

Claims (9)

A charging wake-up circuit is used to wake up a device. The charging and wake-up circuit includes: a first switch, including a first terminal for receiving a first voltage, a second terminal, and a control terminal for receiving a second voltage; a second switch including a first end coupled to the second end of the first switch, a second end, and a control end; a first resistor including a first end coupled to the first The control terminal of two switches and a second terminal are coupled to the first terminal of the second switch; a second resistor includes a first terminal coupled to the second terminal of the second switch, and a second resistor a second end; a third resistor including a first end coupled to the second end of the second resistor and a first end of the device to provide a control voltage to the device, and a second end for to receive a third voltage; and a third switch, comprising a first end coupled to the control end of the second switch, a second end for receiving the third voltage, and a control end coupled to the control end A second end of the device receives a fourth voltage. The charging wake-up circuit as claimed in claim 1, wherein when the first voltage is higher than the second voltage, the first switch and the second switch are turned on, and the control voltage is used to wake up the device, so that the device is powered by A transport mode enters a non-transport mode. The charging wake-up circuit of claim 2, wherein when the first voltage is higher than the second voltage, the control voltage is equal to the difference between the first voltage minus the third voltage, multiplied by the third resistance, and then The quotient obtained by dividing by the sum of the second resistance and the third resistance. The charging wake-up circuit as claimed in claim 1, wherein when the device is woken up, the device adjusts the level of the fourth voltage to turn on the third switch and turn off the second switch, so that the Control voltage drops. The charging wake-up circuit of claim 1, wherein the first switch is a P-type transistor, and the second switch and the third switch are N-type transistors. The charging wake-up circuit of claim 5, wherein: the first end of the first switch, the second end of the second switch and the second end of the third switch are sources; the first switch The second end of the second switch, the first end of the second switch and the first end of the third switch are drains; and the control ends of the first switch, the second switch and the third switch are gates . The charging wake-up circuit of claim 1, wherein when the device has been woken up, the fourth voltage is raised from a low level to a high level. The charging wake-up circuit according to any one of claims 1 to 7, wherein the second voltage is a positive voltage of a battery, the third voltage is a negative voltage of the battery, and the second voltage is higher than the third voltage. The charging wake-up circuit of claim 8, wherein the first voltage is generated by a mains power through a transformer.

Images