Low-power-consumption circuit suitable for MCU (Microprogrammed Control Unit) and electronic equipment

Abstract

The utility model discloses a low power consumption circuit suitable for an MCU and an electronic device, and relates to the technical field of power supply management, the low power consumption circuit comprises a power supply and an MCU which are electrically connected, the output of the MCU controls a post-stage power supply, and the low power consumption circuit is characterized in that a low power consumption control circuit used for controlling the power-on / power-off of the MCU is also connected between the power supply and the MCU. According to the utility model, the low-power-consumption control circuit is additionally arranged, and the MCU is powered on / off through the on / off key signal, so that the power supply of the MCU is controlled, the MCU does not supply power when the CPU system is in a power-off state, the static power consumption of the whole system is almost zero, and more power is saved.

Description

Technical Field

[0001] This utility model relates to the field of power management technology, specifically, to a low-power circuit and electronic device suitable for MCUs. Background Technology

[0002] In a traditional CPU system, the MCU powers on immediately upon connection to an adapter or battery. After powering on, the MCU waits for a power-on signal. Upon receiving the signal, the MCU then proceeds to power on subsequent stages and complete the power-on process. If the system remains off for an extended period, the MCU continues to consume power, reducing battery life. During the CPU system shutdown process, the MCU receives a shutdown signal, executes the shutdown procedure, and cuts power to other external components. After the shutdown process is complete, the MCU itself does not power off. Therefore, even when the system is off, the MCU continues to consume battery power. Thus, whether the system is powered on with a battery or has completed shutdown, in a traditional CPU system, the MCU always has power as long as a battery / power adapter is connected, preventing the system from reaching a low-power state and resulting in continuous power consumption. Utility Model Content

[0003] The purpose of this invention is to provide a low-power circuit and electronic device suitable for MCUs, in order to solve the problem in existing MCU-equipped electronic devices that, as long as a battery / power supply is connected, the MCU will always have power, thus failing to reach a low-power state and continuously consuming power.

[0004] The present invention solves the above problems through the following technical solution:

[0005] A low-power circuit suitable for MCU includes an electrically connected power supply and an MCU, the MCU output controlling a downstream power supply, and a low-power control circuit for controlling the MCU's power-on / power-off is also connected between the power supply and the MCU.

[0006] The low-power control circuit is used to make the connection between the power supply and the MCU open or closed, thereby controlling the MCU to power on or off, so that the MCU is in a power-off state when not in operation and does not consume power.

[0007] Furthermore, the low-power control circuit includes a MOSFET Q1. The source of the MOSFET Q1 is connected to the output terminal of the power supply, and the drain of the MOSFET Q1 is connected to the power input terminal of the MCU. The source of the MOSFET Q1 is also connected to the first terminal of the capacitor C1 of resistor R1. The second terminal of the capacitor C1 of resistor R1 is connected to the gate of the MOSFET Q1 and the first terminal of resistor R2. The second terminal of resistor R2 is connected to the drain of the MOSFET Q2 and the first anode of Schottky diode D2. The second anode of Schottky diode D2 is connected to the input pin of the MCU. The cathode of Schottky diode D2 is connected to the first terminal of resistor R4. The second terminal of resistor R4 is connected to one end of the power button, and the other end of the power button is grounded. The MOSFET Q2 gate is connected to the output pin of the MCU, the first terminal of resistor R3 and capacitor C6, and the second terminals of resistor R3 and capacitor C6, as well as the source of the MOSFET Q2, are grounded.

[0008] Furthermore, the source of the MOS transistor Q1 is also connected to the cathode of the Zener diode D1, and the anode of the Zener diode D1 is grounded.

[0009] Furthermore, the power supply is a battery or an adapter.

[0010] Furthermore, a filter capacitor is also connected to the power supply input terminal of the MCU.

[0011] An electronic device includes a low-power circuit suitable for an MCU, and a CPU powered by the subsequent power supply.

[0012] Compared with the prior art, this utility model has the following advantages and beneficial effects:

[0013] This invention adds a low-power control circuit, which controls the MCU to power on / off via the power button signal, thus controlling the MCU's power supply. When the CPU system is off, the MCU is not powered, and the static power consumption of the entire system is almost zero, resulting in greater energy savings. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the principle of this utility model;

[0015] Figure 2 This is the circuit schematic diagram of the low-power circuit of this utility model. Detailed Implementation

[0016] The present invention will be further described in detail below with reference to the embodiments, but the implementation of the present invention is not limited thereto.

[0017] Example 1:

[0018] Combined with appendix Figure 1 As shown, a low-power circuit suitable for MCU includes an electrically connected power supply and an MCU, the MCU output controls the power supply of the subsequent stage, and a low-power control circuit for controlling the power-on / power-off of the MCU is also connected between the power supply and the MCU.

[0019] The low-power control circuit is used to make the connection between the power supply and the MCU open or closed, thereby controlling the MCU to power on or off, so that the MCU is in a power-off state when not in operation and does not consume power.

[0020] Furthermore, such as Figure 2 As shown, the low-power control circuit includes a MOSFET Q1. The source of the MOSFET Q1 is connected to the output terminal VCC_IN1 of the power supply, and the drain of the MOSFET Q1 is connected to the power input terminal VCC_IN2 of the MCU. The source of the MOSFET Q1 is also connected to the first terminal of the capacitor C1 of resistor R1. The second terminal of the capacitor C1 of resistor R1 is connected to the gate of the MOSFET Q1 and the first terminal of resistor R2. The second terminal of resistor R2 is connected to the drain of the MOSFET Q2 and the first anode of the Schottky diode D2. The second anode of the Schottky diode D2 is connected to the input pin of the MCU. The cathode of the Schottky diode D2 is connected to the first terminal of resistor R4. The second terminal of resistor R4 is connected to one end of the power button, and the other end of the power button is grounded. The MOSFET Q2 gate is connected to the output pin of the MCU, the first terminal of resistor R3 and capacitor C6, and the second terminals of resistor R3 and capacitor C6, as well as the source of the MOSFET Q2, are grounded.

[0021] Working principle:

[0022] When the adapter is plugged in, it connects to AC power, and the power supply output VCC_IN1 powers the adapter. When the adapter is not plugged in, VCC_IN1 powers the battery. VCC_IN1 is always powered as long as the battery has power or the adapter is connected. When the MOSFET Q1 (a PMOS) is turned on, the voltage at the MCU's power supply input VCC_IN2 is equal to VCC_IN1. Therefore, VCC_IN2 is controlled by the MOSFET Q1; it only has power when Q1 is turned on. Typically, the MCU's power supply is provided by a DC / DC power chip. In this invention, the input of the DC / DC power chip is VCC_IN2, and its output is the 3.3V power supply to the MCU. Therefore, controlled VCC_IN2 means controlled 3.3V power to the MCU. Controlled MCU power reduces system static power consumption.

[0023] Specifically:

[0024] When the power is turned on, pressing the power button causes the power button signal PWR_BUTTON to go low. This causes the first positive terminal (pin 2) of the Schottky diode D2 to also go low. At this time, the gate (G) of MOSFET Q1 is smaller than its source (S), so MOSFET Q1 is turned on, and the S terminal equals the D terminal. Therefore, VCC_IN2 is equal to VCC_IN1. When VCC_IN2 is powered on, the MCU will be powered on. The time from pressing the power button to the MCU powering on is much shorter than the time it takes for the power button to rebound. Therefore, the MCU is already powered on before the power button rebounds. The input pin of the MCU connected to the second positive terminal of the Schottky diode D2 is at a low level (i.e., the MCU receives the power-on signal MCU_PWR_BUTTON). The output pin of the MCU connected to the gate of MOSFET Q2 (NMOS transistor) outputs a high level as the control signal MCU_PWR_EN for MOSFET Q2. Since the gate (G) of MOSFET Q2 is greater than the source (S), Q2 is turned on. The drain (D) of Q2 is pulled low, so MOSFET Q1 is turned on. VCC_IN2 equals VCC_IN1, ensuring continuous power to VCC_IN2. Even if the power button rebounds, the MCU remains powered on. After this process is completed, the MCU then turns on the subsequent power supply and executes the power-on procedure. This complete power-on procedure shows that the MCU will not power on if it does not receive a power button signal, ensuring low power consumption and saving battery power.

[0025] When the system is powered off, pressing the power button generates a low pulse in the power button signal PWR_BUTTON. The input pin connected to the Schottky diode D2 receives this low pulse signal and executes the power-off process. After the power-off process is complete, the output pin connected to the gate of the MOSFET Q2 outputs a low level, meaning the control signal MCU_PWR_EN for MOSFET Q2 is low. At this time, Q2 will not conduct, and Q1 will also not conduct, so VCC_IN2 will not have power, and the MCU will power down. Therefore, after power-off, the MCU also power down, resulting in very low static power consumption and effectively reducing battery consumption. This invention solves the problem of the MCU failing to power down when the device is not powered on or off.

[0026] Furthermore, the source of the MOS transistor Q1 is also connected to the cathode of the Zener diode D1, and the anode of the Zener diode D1 is grounded.

[0027] Furthermore, a filter capacitor is also connected to the power supply input terminal of the MCU.

[0028] Example 2:

[0029] An electronic device includes a low-power circuit suitable for an MCU as described in Embodiment 1, and further includes a CPU powered by the subsequent power supply.

[0030] Although the present invention has been described herein with reference to illustrative embodiments, the above embodiments are merely preferred embodiments of the present invention, and the implementation of the present invention is not limited to the above embodiments. It should be understood that those skilled in the art can design many other modifications and implementations, which will fall within the scope and spirit of the principles disclosed in this application.

Claims

1. A low-power circuit suitable for an MCU, comprising an electrically connected power supply and an MCU, wherein the MCU outputs a control signal to the subsequent power supply, characterized in that, A low-power control circuit for controlling the power-on / power-off of the MCU is also connected between the power supply and the MCU. The low-power control circuit includes a MOSFET Q1. The source of the MOSFET Q1 is connected to the output terminal of the power supply, and the drain of the MOSFET Q1 is connected to the power input terminal of the MCU. The source of the MOSFET Q1 is also connected to the first terminal of the capacitor C1 of resistor R1. The second terminal of the capacitor C1 of resistor R1 is connected to the gate of the MOSFET Q1 and the first terminal of resistor R2. The second terminal of resistor R2 is connected to the drain of the MOSFET Q2 and the first anode of Schottky diode D2. The second anode of Schottky diode D2 is connected to the input pin of the MCU. The cathode of Schottky diode D2 is connected to the first terminal of resistor R4. The second terminal of resistor R4 is connected to one end of the power button, and the other end of the power button is grounded. The circuit connecting the gate of the MOSFET Q2 to the output pin of the MCU, the first terminal of resistor R3 and capacitor C6, the second terminals of resistor R3 and capacitor C6, and the source of the MOSFET Q2 are grounded.

2. The low-power circuit suitable for MCU according to claim 1, characterized in that, The source of the MOS transistor Q1 is also connected to the cathode of the Zener diode D1, and the anode of the Zener diode D1 is grounded.

3. A low-power circuit suitable for MCUs according to claim 1, characterized in that, The power supply is either a battery or an adapter.

4. A low-power circuit suitable for MCUs according to claim 1, characterized in that, The MCU's power input terminal is also connected to a filter capacitor.

5. An electronic device, characterized in that, It includes a low-power circuit suitable for an MCU as described in any one of claims 1-4, and further includes a CPU powered by the subsequent power supply.

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