A portable device power management system
By using a power-on control circuit and a power-on request confirmation circuit, the voltage glitches caused by the mechanical button power supply method in portable devices are resolved, achieving reliability and flexibility in power management and reducing hardware complexity and cost.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHENZHEN GAOKERUN ELECTRONICS CO LTD
- Filing Date
- 2026-04-30
- Publication Date
- 2026-06-12
AI Technical Summary
The mechanical button power supply method of portable devices causes voltage glitches, which can easily cause MCU reset or program crashes, resulting in low system reliability. Furthermore, traditional hardware circuits are difficult to implement complex power management logic.
A portable device power management system was designed. It receives the 5V_LOCK self-locking signal from the MCU through a conduction control circuit to achieve power supply self-locking. Combined with the switching circuit and the MCU power supply circuit, it ensures the stability of the power supply. It also implements complex power management strategies through a power-on request confirmation circuit.
It eliminates the interference of mechanical button bounce on the system power supply, ensures the reliability of startup, and realizes complex power management strategies such as long press to shut down and timed shutdown, reducing hardware complexity and cost.
Smart Images
Figure CN122204015A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of power management, specifically a power management system for portable devices. Background Technology
[0002] Currently, many portable devices (such as handheld terminals and data acquisition devices) use mechanical buttons as main power switches. In traditional circuit designs, the buttons directly control the on / off state of the power supply circuit. This approach has significant drawbacks: First, mechanical buttons generate contact bounce at the moment of closure, which may cause voltage spikes in the power supply. If directly powering a microcontroller unit (MCU), this can easily trigger an MCU reset or program crash, resulting in low system reliability. Second, if complex logic such as "short press to power on, long press to power off" or software-controlled shutdown is desired, traditional pure hardware circuits are difficult to implement, resulting in insufficient system flexibility and requiring improvement. Summary of the Invention
[0003] The purpose of this invention is to provide a power management system for portable devices to solve the problems mentioned in the background art.
[0004] To achieve the above objectives, the present invention provides the following technical solution: A portable device power management system, comprising: A switching circuit is used to control the operation of the conduction control circuit and the power-on request confirmation circuit by manually controlling whether the switch is closed. The turn-on control circuit is used to control the operation of the MCU power supply circuit during operation; it receives the 5V_LOCK self-locking signal output by the MCU and maintains the operation of the MCU power supply circuit after the switch is opened. The MCU power supply circuit is used to supply power to the MCU during operation and drive the MCU to power on and work. The power-on request confirmation circuit is used to send a valid power-on request signal SW_CHK back to the MCU during operation. The output of the switching circuit is connected to the input of the turn-on control circuit, the input of the power-on request confirmation circuit, and the first input of the MCU power supply circuit. The output of the turn-on control circuit is connected to the second input of the MCU power supply circuit.
[0005] As a further embodiment of the present invention: the switching circuit includes a power supply B+ and a switch SW1. The power supply B+ is connected to one end of the switch SW1, and the other end of the switch SW1 is connected to the input terminal of the conduction control circuit and the input terminal of the power-on request confirmation circuit.
[0006] As a further embodiment of the present invention: the conduction control circuit includes diode D4, diode D5, and transistor Q2. The anode of diode D4 is connected to the output terminal of the switching circuit, and the cathode of diode D4 is connected to one end of capacitor C14 and one end of resistor R15. The other end of capacitor C14 is connected to the other end of resistor R15, the cathode of diode D5, and one end of resistor R39. The anode of diode D5 receives the 5V_LOCK self-locking signal output by the MCU. The other end of resistor R39 is connected to the base of transistor Q2. The emitter of transistor Q2 is grounded. The collector of transistor Q2 is connected to one end of resistor R10. The other end of resistor R10 is connected to the second input terminal of the MCU power supply circuit.
[0007] As a further embodiment of the present invention: the MCU power supply circuit includes a MOSFET Q1 and a voltage regulator chip U2, the voltage regulator chip U2 being an AP2000. The source (S) of the MOSFET Q1 is connected to one end of resistor R28 and the output terminal of the switching circuit. The other end of resistor R28 is connected to the output terminal of the conduction control circuit and the gate (G) of the MOSFET Q1. The drain (D) of the MOSFET Q1 is connected to the anode of diode D3. The cathode of diode D3 is connected to one end of resistor R23. The other end of resistor R23 is connected to one end of capacitor C4, one end of capacitor C8, one end of inductor L1, one end of resistor R33, and the voltage regulator chip. Pin 6 of chip U2 is connected to pin 4 of voltage regulator chip U2. The other end of capacitor C4 and the other end of capacitor C8 are grounded. The other end of resistor R33 is connected to pin 4 of voltage regulator chip U2. The other end of inductor L1 is connected to pin 1 of voltage regulator chip U2. Pin 5 of chip U2 outputs 5V voltage to power the MCU. Pin 5 of chip U2 is connected to one end of resistor R25, one end of capacitor C5, and one end of capacitor C7. The other end of capacitor C5 and the other end of capacitor C7 are grounded. The other end of resistor R25 is connected to one end of resistor R36 and pin 3 of voltage regulator chip U2. The other end of resistor R36 is grounded.
[0008] As a further embodiment of the present invention: the power-on request confirmation circuit includes a MOSFET Q6. The gate (G) of the MOSFET Q6 is connected to one end of resistor R47 and one end of resistor R48. The other end of resistor R47 is connected to the output terminal of the switching circuit. The other end of resistor R48 is grounded. The source (S) of the MOSFET Q6 is grounded. The drain (D) of the MOSFET Q6 is connected to one end of resistor R44 and one end of resistor R46. The other end of resistor R44 is connected to a 5V power supply. The other end of resistor R46 is connected to one end of capacitor C15. The other end of capacitor C15 is grounded. The voltage across capacitor C15 is the valid power-on request signal SW_CHK.
[0009] Compared with the prior art, the beneficial effects of the present invention are as follows: The conduction control circuit designed in this invention receives the self-locking signal 5V_LOCK output by the MCU, and self-locks after power supply is completed, eliminating the interference of mechanical button bounce on the system power supply and ensuring reliable startup; the power supply control of subsequent circuits depends on the self-locking signal 5V_LOCK, and the final power supply control belongs to the MCU, making it easy to implement complex power management strategies such as long press to shut down, timed shutdown, and automatic shutdown when low battery is reached; the circuit components are common components, eliminating the need for dedicated power management chips, thus reducing hardware complexity and cost. Attached Figure Description
[0010] Figure 1 This is a circuit diagram of a power management system for a portable device. Detailed Implementation
[0011] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.
[0012] Please see Figure 1 A portable device power management system, comprising: A switching circuit is used to control the operation of the conduction control circuit and the power-on request confirmation circuit by manually controlling whether the switch is closed. The turn-on control circuit is used to control the operation of the MCU power supply circuit during operation; it receives the 5V_LOCK self-locking signal output by the MCU and maintains the operation of the MCU power supply circuit after the switch is opened. The MCU power supply circuit is used to supply power to the MCU during operation and drive the MCU to power on and work. The power-on request confirmation circuit is used to send a valid power-on request signal SW_CHK back to the MCU during operation. The output of the switching circuit is connected to the input of the turn-on control circuit, the input of the power-on request confirmation circuit, and the first input of the MCU power supply circuit. The output of the turn-on control circuit is connected to the second input of the MCU power supply circuit.
[0013] In this embodiment: Please refer to Figure 1 The switching circuit includes a power supply B+ and a switch SW1. The power supply B+ is connected to one end of the switch SW1, and the other end of the switch SW1 is connected to the input terminal of the conduction control circuit and the input terminal of the power-on request confirmation circuit.
[0014] When switch SW1 is pressed, it will pop up. When the user presses switch SW1, power supply B+ is supplied through switch SW1.
[0015] In this embodiment: Please refer to Figure 1 The conduction control circuit includes diodes D4 and D5, and transistor Q2. The anode of diode D4 is connected to the output terminal of the switching circuit, and the cathode of diode D4 is connected to one end of capacitor C14 and one end of resistor R15. The other end of capacitor C14 is connected to the other end of resistor R15, the cathode of diode D5, and one end of resistor R39. The anode of diode D5 receives the 5V_LOCK self-locking signal output by the MCU. The other end of resistor R39 is connected to the base of transistor Q2. The emitter of transistor Q2 is grounded, and the collector of transistor Q2 is connected to one end of resistor R10. The other end of resistor R10 is connected to the second input terminal of the MCU power supply circuit.
[0016] Power supply B+ triggers transistor Q2 to conduct through switch SW1, diode D4, resistor R15, and resistor R39. After transistor Q2 conducts, it pulls down the voltage at resistor R10.
[0017] In this embodiment: Please refer to Figure 1 The MCU power supply circuit includes MOSFET Q1 and voltage regulator chip U2 (model AP2000). The source (S) of MOSFET Q1 is connected to one end of resistor R28 and the output of the switching circuit. The other end of resistor R28 is connected to the output of the conduction control circuit and the gate (G) of MOSFET Q1. The drain (D) of MOSFET Q1 is connected to the anode of diode D3. The cathode of diode D3 is connected to one end of resistor R23. The other end of resistor R23 is connected to one end of capacitor C4, one end of capacitor C8, one end of inductor L1, one end of resistor R33, and pin 6 of voltage regulator chip U2. The pins are connected as follows: the other end of capacitor C4 is grounded, the other end of capacitor C8 is grounded, the other end of resistor R33 is connected to pin 4 of voltage regulator chip U2, the other end of inductor L1 is connected to pin 1 of voltage regulator chip U2, pin 5 of chip U2 outputs 5V voltage to power the MCU, pin 5 of chip U2 is connected to one end of resistor R25, one end of capacitor C5, one end of capacitor C7, the other end of capacitor C5 is grounded, the other end of capacitor C7 is grounded, the other end of resistor R25 is connected to one end of resistor R36 and pin 3 of voltage regulator chip U2, and the other end of resistor R36 is grounded.
[0018] After transistor Q2 is turned on, the gate voltage of MOSFET Q1 (PMOS) is pulled low, MOSFET Q1 is turned on, and power is supplied to voltage regulator chip U2. Voltage regulator chip provides MCU with a stable 5V voltage, triggering MCU to start.
[0019] In this embodiment: Please refer to Figure 1The power-on request confirmation circuit includes MOSFET Q6. The gate (G) of MOSFET Q6 is connected to one end of resistor R47 and one end of resistor R48. The other end of resistor R47 is connected to the output terminal of the switching circuit, and the other end of resistor R48 is grounded. The source (S) of MOSFET Q6 is grounded. The drain (D) of MOSFET Q6 is connected to one end of resistor R44 and one end of resistor R46. The other end of resistor R44 is connected to a 5V power supply, and the other end of resistor R46 is connected to one end of capacitor C15. The other end of capacitor C15 is grounded. The voltage across capacitor C15 is the valid power-on request signal SW_CHK.
[0020] In the initial state of the system, transistor Q2 and MOSFET Q1 are cut off, chip U2 has no input, and the MCU is not powered. When switch SW1 is turned on, the B+ voltage provides base current to transistor Q2 through diode D4, capacitor C14, and resistor R39, turning on transistor Q2 and pulling its collector potential low. This pulls down the collector potential, which in turn turns on MOSFET Q1 through resistor network R16 and R19. The B+ voltage then powers chip U2 via MOSFET Q1, and chip U2 outputs 5V to the MCU. Simultaneously, the action of turning on switch SW1 pulls the SW_CHK detection point low (this can be achieved by connecting a pull-up resistor to ground). After the MCU powers on and initializes, it reads SW_CHK as low, interprets this as a user power-on command, and then sets the 5V_LOCK signal high. The 5V_LOCK signal maintains the conduction state of transistor Q2 through diode D4 and other paths. The base current of transistor Q2 is provided by the 5V_LOCK signal, thus achieving self-sustaining power supply. Even if the user forgets to turn off the device (i.e., does not disconnect switch SW1), the MCU program can be set to set the 5V_LOCK signal to low level after 2 hours (depending on the user's usage habits). This will cause transistor Q2 to lose its base current and turn off, which in turn will turn off MOSFET Q1. The input of chip U2 will be cut off, the 5V output will be turned off, the MCU will lose power, and the entire system will return to an extremely low power standby state (approximately 5uA).
[0021] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and not restrictive.
[0022] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.
Claims
1. A power management system for portable devices, characterized in that, The portable device power management system includes: A switching circuit is used to control the operation of the conduction control circuit and the power-on request confirmation circuit by manually controlling whether the switch is closed. The turn-on control circuit is used to control the operation of the MCU power supply circuit during operation; it receives the 5V_LOCK self-locking signal output by the MCU and maintains the operation of the MCU power supply circuit after the switch is opened. The MCU power supply circuit is used to supply power to the MCU during operation and drive the MCU to power on and work. The power-on request confirmation circuit is used to send a valid power-on request signal SW_CHK back to the MCU during operation. The output of the switching circuit is connected to the input of the turn-on control circuit, the input of the power-on request confirmation circuit, and the first input of the MCU power supply circuit. The output of the turn-on control circuit is connected to the second input of the MCU power supply circuit.
2. The portable device power management system according to claim 1, characterized in that, The switching circuit includes a power supply B+ and a switch SW1. The power supply B+ is connected to one end of the switch SW1, and the other end of the switch SW1 is connected to the input terminal of the conduction control circuit and the input terminal of the power-on request confirmation circuit.
3. The portable device power management system according to claim 1, characterized in that, The conduction control circuit includes diodes D4 and D5, and transistor Q2. The anode of diode D4 is connected to the output terminal of the switching circuit, and the cathode of diode D4 is connected to one end of capacitor C14 and one end of resistor R15. The other end of capacitor C14 is connected to the other end of resistor R15, the cathode of diode D5, and one end of resistor R39. The anode of diode D5 receives the 5V_LOCK self-locking signal output by the MCU. The other end of resistor R39 is connected to the base of transistor Q2. The emitter of transistor Q2 is grounded, and the collector of transistor Q2 is connected to one end of resistor R10. The other end of resistor R10 is connected to the second input terminal of the MCU power supply circuit.
4. The portable device power management system according to claim 3, characterized in that, The MCU power supply circuit includes MOSFET Q1 and voltage regulator chip U2 (model AP2000). The source (S) of MOSFET Q1 is connected to one end of resistor R28 and the output of the switching circuit. The other end of resistor R28 is connected to the output of the turn-on control circuit and the gate (G) of MOSFET Q1. The drain (D) of MOSFET Q1 is connected to the anode of diode D3. The cathode of diode D3 is connected to one end of resistor R23. The other end of resistor R23 is connected to one end of capacitor C4, one end of capacitor C8, one end of inductor L1, one end of resistor R33, and pin 6 of voltage regulator chip U2. The pins are connected as follows: the other end of capacitor C4 is grounded, the other end of capacitor C8 is grounded, the other end of resistor R33 is connected to pin 4 of voltage regulator chip U2, the other end of inductor L1 is connected to pin 1 of voltage regulator chip U2, pin 5 of chip U2 outputs 5V voltage to power the MCU, pin 5 of chip U2 is connected to one end of resistor R25, one end of capacitor C5, one end of capacitor C7, the other end of capacitor C5 is grounded, the other end of capacitor C7 is grounded, the other end of resistor R25 is connected to one end of resistor R36 and pin 3 of voltage regulator chip U2, and the other end of resistor R36 is grounded.
5. The portable device power management system according to claim 3, characterized in that, The power-on request confirmation circuit includes MOSFET Q6. The gate (G) of MOSFET Q6 is connected to one end of resistor R47 and one end of resistor R48. The other end of resistor R47 is connected to the output terminal of the switching circuit, and the other end of resistor R48 is grounded. The source (S) of MOSFET Q6 is grounded. The drain (D) of MOSFET Q6 is connected to one end of resistor R44 and one end of resistor R46. The other end of resistor R44 is connected to a 5V power supply, and the other end of resistor R46 is connected to one end of capacitor C15. The other end of capacitor C15 is grounded. The voltage across capacitor C15 is the valid power-on request signal SW_CHK.