CN218995502U

CN218995502U - Chip load detection circuit

Info

Publication number: CN218995502U
Application number: CN202320073988.9U
Authority: CN
Inventors: 张彦飞
Original assignee: Shenzhen Honestar Electronic Co ltd
Current assignee: Shenzhen Honestar Electronic Co ltd
Priority date: 2023-01-10
Filing date: 2023-01-10
Publication date: 2023-05-09
Anticipated expiration: 2033-01-10

Abstract

The utility model discloses a chip load detection circuit which comprises a chip carrier, and a control unit MCU, a positive electrode end and a negative electrode end which are arranged on the chip carrier, wherein the control unit MCU is provided with an ADC pin, the positive electrode end is an output voltage end, a resistor R1 and a capacitor C1 are connected in series on a lead of the negative electrode end, and a middle lead of the resistor R1 and the capacitor C1 is electrically connected to the ADC pin; the negative electrode end is further electrically connected with a switching tube Q1, a load current detection resistor R3 is further connected in series between the negative electrode end and the switching tube Q1, the switching tube Q1 is electrically connected with a sensor, the switching tube Q1 is controlled by a signal of the sensor to be started, and when a load is connected, the switching tube Q1 is started. The number of elements is small, and the cost is low; the principle is simple, and the access control unit MCU can be easily realized; the load current detection capability is achieved, and the power supply end and the power receiving equipment are protected.

Description

Chip load detection circuit

Technical Field

The utility model relates to the field of load detection, in particular to a chip load detection circuit.

Background

Currently, mobile devices such as smartphones, wearable devices, electric tools, unmanned aerial vehicles and the like are increasingly used. Charge and discharge circuitry in mobile devices is an important component. The automatic load detection circuit is a basic circuit of the charge and discharge circuit, and is beneficial to improving the reliability of the charge and discharge circuit.

In some products for charging external devices, the capability of turning off the external charging is generally provided for safety when no external device is connected, so that unexpected faults caused by voltage output can be prevented, and therefore, a detection circuit which can be easily implemented and can detect load current to protect a power supply terminal is needed.

Disclosure of Invention

In view of the foregoing, the present utility model aims to provide a simple and low-cost load detection circuit.

In order to achieve the technical purpose, the scheme of the utility model is as follows: the chip load detection circuit comprises a chip carrier, and a control unit MCU, a positive electrode end and a negative electrode end which are arranged on the chip carrier, wherein the control unit MCU is provided with an ADC pin, the positive electrode end is an output voltage end, a resistor R1 and a capacitor C1 are connected in series on a lead of the negative electrode end, and a middle lead of the resistor R1 and the capacitor C1 is electrically connected to the ADC pin;

the negative electrode end is further electrically connected with a switching tube Q1, a load current detection resistor R3 is further connected in series between the negative electrode end and the switching tube Q1, the switching tube Q1 is electrically connected with a sensor, the switching tube Q1 is controlled by a signal of the sensor to be started, and when a load is connected, the switching tube Q1 is started.

Preferably, the capacitor C1 is electrically connected to the ground, and the switching tube Q1 is electrically connected to the ground.

Preferably, a resistor R2 is connected in series between the switching tube and the sensor.

Preferably, the capacitor C1 is a 0.1uF capacitor, and the resistor R1 is a 1K resistor.

Preferably, the switching transistor Q1 is an NMOS transistor.

Preferably, the sensor is an en_mos electric field microsensor.

The beneficial effects of the utility model are as follows: the number of elements is small, and the cost is low; the principle is simple, and the access control unit MCU can be easily realized; the load current detection capability is achieved, and the power supply end and the power receiving equipment are protected.

Drawings

FIG. 1 is a schematic diagram of the present utility model.

Detailed Description

The utility model will now be described in further detail with reference to the drawings and to specific examples. For a clear and complete description of the technical solutions, the following examples are chosen for illustration; the following examples are some of the examples of the present utility model; other embodiments, which are obtained without making any inventive effort, are within the scope of the present utility model based on the present application.

In the following embodiments, it should be noted that, the terms "upper", "lower", "left", "right", "inner", "outer", "top/bottom", and the like are all based on the orientation or positional relationship shown in the drawings, and are merely for the sake of clarity in describing the present embodiment, and do not indicate or imply that the apparatus or element to be referred to must have a specific orientation, and therefore should not be construed as limiting the present application. Meanwhile, the "first" and "second" in the embodiments are used for distinguishing descriptive purposes only and are not represented as indicating or implying relative importance.

Example 1

As shown in fig. 1, a chip load detection circuit is configured to implement load access detection by using a simple low-cost circuit in combination with control of a control unit MCU (chip), and to detect load current. For the product that has the control unit MCU control, can use the load detection circuit that this patent provided, when detecting that there is the load to connect, just begin to charge outward, the circuit is the shut-off output at the normal state.

The detection circuit comprises a chip carrier, and a control unit MCU, a positive terminal and a negative terminal which are arranged on the chip carrier, wherein the control unit MCU is provided with an ADC pin, the positive terminal of VCC is an output voltage terminal VOUT, a resistor R1 and a capacitor C1 (the capacitor C1 is a 0.1uF capacitor, the resistor R1 is a 1K resistor) are connected in series on a lead wire of the negative terminal VSS, and the middle lead wires of the resistor R1 and the capacitor C1 are electrically connected to the ADC pin;

the negative end of the load connecting wire is also electrically connected with a switching tube Q1, the switching tube Q1 is an NMOS transistor, a load current detection resistor R3 is connected in series above the switching tube Q1, the switching tube Q1 is electrically connected with a sensor which is an EN_MOS electric field microsensor capable of measuring the electric field intensity, the switching tube Q1 is started under the control of signals of the EN_MOS electric field microsensor, and when a load is connected, the switching tube Q1 is started.

The capacitor C1 is electrically connected to the ground, the switching tube Q1 is electrically connected to the ground, and the working process is as follows: normally, the switching tube Q1 is turned off, and the charge on the C1 capacitor is released through the ADC pin of the control unit MCU, and the voltage of the ADC pin is 0V. The control unit MCU continuously inquires the voltage value of the ADC pin. When a load is connected, the voltage of the positive end of the passage is output to the load to the resistor R1 to charge the capacitor C1, and when the voltage of the capacitor C1 rises above a specified threshold voltage, the load is judged to be connected.

A resistor R2 is connected in series between the switching tube and the sensor, when a load is connected in, the EN_MOS electric field microsensor controls the resistor R2 to enable the switching tube Q1 to be turned on to normally supply power to the load, meanwhile, for the safety of work, the control unit MCU still continuously monitors the voltage drop on the resistor R3 in the power supply process of the load, the resistor R3 is a load current detection resistor, and when the current exceeds a set current threshold value, output is judged to protect a power supply end and powered equipment.

The load detection circuit has few elements and low cost; the principle is simple, and the control unit MCU can be easily realized (the control unit MCU is suitable for products with MCU chip control); the load current detection capability is achieved, and the power supply end and the power receiving equipment are protected.

The battery charger is particularly suitable for some products for charging external equipment, and can automatically turn off the external charging capability when no external equipment is connected; in the use process, output is normally turned off, and external charging is started only when load access is detected, so that accidental faults caused by voltage output are effectively prevented.

The foregoing description is only of the preferred embodiments of the present utility model, and is not intended to limit the utility model, but any minor modifications, equivalents, and improvements made to the above embodiments according to the technical principles of the present utility model should be included in the scope of the technical solutions of the present utility model.

Claims

1. The utility model provides a chip load detection circuit, includes chip carrier and the control unit MCU that is equipped with on chip carrier, positive terminal and negative terminal, its characterized in that: the control unit MCU is provided with an ADC pin, the positive end is an output voltage end, a resistor R1 and a capacitor C1 are connected in series on a lead of the negative end, and a middle lead of the resistor R1 and the capacitor C1 is electrically connected to the ADC pin;

2. The chip load detection circuit according to claim 1, wherein: the capacitor C1 is electrically connected to the ground, and the switching tube Q1 is electrically connected to the ground.

3. The chip load detection circuit according to claim 2, wherein: a resistor R2 is connected in series between the switching tube and the sensor.

4. A chip load detection circuit according to any one of claims 1-3, characterized in that: the capacitor C1 is a 0.1uF capacitor, and the resistor R1 is a 1K resistor.

5. A chip load detection circuit according to any one of claims 1-3, characterized in that: the switching transistor Q1 is an NMOS transistor.

6. A chip load detection circuit according to any one of claims 1-3, characterized in that: the sensor is an EN_MOS electric field microsensor.