CN-122001065-A - Charging control circuit, charging chip and power supply device

CN122001065ACN 122001065 ACN122001065 ACN 122001065ACN-122001065-A

Abstract

The application belongs to the field of electronic circuits, and provides a charging control circuit, a charging chip and a power supply device. The circuit comprises a first switch module, a second switch module, a control module, a current loop module and a voltage loop module, wherein the control module is respectively connected with the current loop module, the voltage loop module, the first switch module and the second switch module, the first switch module is respectively connected with the current loop module, the voltage loop module, the boost driving module and the grid electrode of the charging power tube, and the second switch module is respectively connected with an output node in the charging circuit and the grid electrode of the charging power tube. When the battery voltage is greater than or equal to the fast charge threshold, the current reference value of the current loop module is switched, so that the charging current continuously rises from the slow charge current at a stable speed. When the charging current rises to be slightly smaller than the fast charging current, the conduction degree of the charging power tube is close to complete conduction, and at the moment, the loop switching is performed again, so that uncontrolled current or an excessively large peak cannot be generated.

Inventors

NIE DAN
CHENG YONGPENG

Assignees

深圳市微源半导体股份有限公司

Dates

Publication Date: 20260508
Application Date: 20260408

Claims (10)

1. The charging control circuit is characterized by comprising a first switch module, a second switch module, a control module, a current loop module and a voltage loop module, wherein the control module is respectively connected with the current loop module, the voltage loop module, the first switch module and the second switch module, the first switch module is respectively connected with the current loop module, the voltage loop module, a boost driving module in a charging circuit and a grid electrode of a charging power tube in the charging circuit, and the second switch module is respectively connected with an output node in the charging circuit and the grid electrode of the charging power tube; When the voltage of a battery is smaller than a fast charge threshold, the control module is used for outputting a first control signal to the first switch module, the first switch module is used for controlling the voltage loop module to be connected with the boost driving module in a conducting way according to the first control signal and controlling the current loop module to be connected with the grid electrode of the charging power tube in a conducting way, the voltage loop module is used for controlling the boost driving module according to a first voltage reference value so as to adjust the duty ratio of a first power tube and a second power tube in the charging circuit and enable the output voltage in the charging circuit to be maintained at a voltage higher than an input voltage preset value, the current loop module is used for controlling the charging power tube to be in a incompletely conducting state according to the first current reference value and enabling charging current to be charged for the battery according to a first target current, and the second switch module is used for outputting a first voltage to the grid electrode of the charging power tube according to the output voltage and outputting a first level signal to the control module according to the first voltage and the grid electrode voltage conduction of the charging power tube; The control module is used for outputting a first adjusting signal to the current loop module according to the first level signal when the battery voltage is larger than or equal to a fast charge threshold value, and the current loop module is used for adjusting the first current reference value to a second current reference value according to the first adjusting signal and continuously pulling up the grid voltage of the charging power tube according to the second current reference value, and controlling the second switch module to be disconnected when the grid voltage of the charging power tube rises to a preset voltage so as to enable the second switch module to output a second level signal to the control module; The control module is used for outputting a second control signal to the first switch module according to a second level signal and outputting a second adjustment signal to the voltage loop module at the same time, the first switch module is used for controlling the current loop module to be connected with the boost driving module in a conducting manner according to the second control signal and controlling the voltage loop module to be connected with the grid electrode of the charging power tube in a conducting manner, the current loop module is used for controlling the boost driving module according to the second current reference value so as to adjust the duty ratio of the first power tube and the second power tube to enable the charging current to be equal to a second target current, and the voltage loop module is used for adjusting the first voltage reference value to be a second voltage reference value according to the second adjustment signal and continuously pulling up the grid electrode voltage of the charging power tube according to the second voltage reference value; When the grid voltage of the charging power tube is equal to the first voltage, the charging power tube is fully conducted, and the charging current charges the battery by the second target current.
2. The charge control circuit of claim 1, wherein the second switch module comprises a charge pump unit, a first current unit, a second current unit, a third current unit, and a switch unit, the charge pump unit being respectively connected to the output node, the second current unit, and the third current unit, the switch unit being respectively connected to the second current unit, the first current unit, and the control module, the third current unit and the switch unit each being for connection to a gate of the charge power tube; When the battery voltage is smaller than a fast charge threshold, the charge pump unit is used for outputting a first voltage according to the output voltage, the first current unit is used for providing a first current, the second current unit is used for providing a second current and transmitting the first voltage to the switch unit, the third current unit is used for providing a third current and transmitting the first voltage to a grid electrode of the charging power tube, and the switch unit is used for conducting according to the grid voltage of the charging power tube and the first voltage and outputting a first level signal to the control module based on the first current and the second current; When the battery voltage is greater than or equal to a fast charge threshold and the grid voltage of the charging power tube rises to a preset voltage, the switch unit is used for disconnecting according to the first voltage and the grid voltage of the charging power tube, and the first current unit is used for outputting a second level signal to the control module.
3. The charge control circuit of claim 2 wherein the first current unit comprises a first current source having a first terminal connected to the switch unit and the control module, respectively, and a second terminal connected to ground.
4. The charge control circuit of claim 2 wherein the second current source comprises a second current source having a first terminal connected to the charge pump unit and a second terminal connected to the switch unit.
5. The charge control circuit of claim 2 wherein the second current is twice the first current.
6. The charge control circuit of claim 2, wherein the switching unit comprises a first switching tube, a gate of the first switching tube is used for being connected with a gate of the charge power tube, a source of the first switching tube is connected with the second current unit, and a drain of the first switching tube is respectively connected with the first current unit and the control module.
7. The charge control circuit of claim 6 wherein the first switching tube is a PMOS tube.
8. The charge control circuit of claim 2 wherein the third current unit comprises a third current source having a first terminal connected to the charge pump unit and a second terminal for connection to the gate of the charge power tube.
9. A charging chip, characterized by comprising a charging circuit and the charging control circuit according to any one of claims 1-8, wherein a boost driving module in the charging circuit is connected with a first switch module in the charging control circuit, an output node in the charging circuit is connected with a second switch module in the charging control circuit, and a grid electrode of a charging power tube in the charging circuit is respectively connected with the second switch module and the first switch module in the charging control circuit.
10. A power supply device comprising the charging chip of claim 9.

Description

Charging control circuit, charging chip and power supply device Technical Field The present application relates to electronic circuits, and particularly to a charging control circuit, a charging chip, and a power supply device. Background In a power supply system of portable electronic equipment and energy storage equipment, a boost charging chip is a core device for supplying power to a lithium battery. The method for charging the lithium battery by the boost charging chip comprises linear charging and switch charging, and for the lithium battery, the boost charging chip is divided into two stages of low-current slow charging and high-current fast charging according to the voltage of the battery. In practical application, the low-current slow charging stage is realized by adopting a linear charging mode, and the high-current fast charging stage is realized by adopting a switch charging mode. In order to realize the above-mentioned sectional charging, the conventional boost charging chip generally adopts a control mode of "loop switching". In the low-current slow charging stage, a voltage loop controls a boost driving module in a boost charging chip, the duty ratio of a first power tube and a second power tube is adjusted to enable the output voltage to be maintained at a fixed value higher than the input voltage, and meanwhile, a current loop controls the grid electrode of a charging power tube to enable the charging power tube to work in an incomplete conduction state, so that the charging current is ensured to be stable at a slow charging current. When the battery voltage reaches the fast charge threshold, the grid electrode of the charging power tube is required to be pulled up to be fully conducted, and meanwhile, the boost driving module is required to be switched to be controlled by a current loop, so that the charging current is ensured to be stabilized at the fast charge current, namely, the high-current fast charge stage is entered. Although the control mode can complete the switching process from linear low-current slow charging to switch high-current fast charging more surely, the problem that the charging process is not smooth and short-time stop occurs during switching exists. Disclosure of Invention The embodiment of the application provides a charging control circuit, a charging chip and a power supply device, which can solve the problems that the charging process is not smooth and short stopping occurs during the switching process in the process of switching the traditional boost charging chip from linear low current to switch high current. In a first aspect, an embodiment of the present application provides a charging control circuit, including a first switch module, a second switch module, a control module, a current loop module, and a voltage loop module, where the control module is connected to the current loop module, the voltage loop module, the first switch module, and the second switch module, the first switch module is connected to the current loop module, the voltage loop module, a boost driving module in a charging circuit, and a gate of a charging power tube in the charging circuit, and the second switch module is connected to an output node in the charging circuit and the gate of the charging power tube; When the voltage of a battery is smaller than a fast charge threshold, the control module is used for outputting a first control signal to the first switch module, the first switch module is used for controlling the voltage loop module to be connected with the boost driving module in a conducting way according to the first control signal and controlling the current loop module to be connected with the grid electrode of the charging power tube in a conducting way, the voltage loop module is used for controlling the boost driving module according to a first voltage reference value so as to adjust the duty ratio of a first power tube and a second power tube in the charging circuit and enable the output voltage in the charging circuit to be maintained at a voltage higher than an input voltage preset value, the current loop module is used for controlling the charging power tube to be in a incompletely conducting state according to the first current reference value and enabling charging current to be charged for the battery according to a first target current, and the second switch module is used for outputting a first voltage to the grid electrode of the charging power tube according to the output voltage and outputting a first level signal to the control module according to the first voltage and the grid electrode voltage conduction of the charging power tube; The control module is used for outputting a first adjusting signal to the current loop module according to the first level signal when the battery voltage is larger than or equal to a fast charge threshold value, and the current loop module is used for adjusting the first current reference value to a second current reference