A soft-start switch circuit for battery-powered main circuits

Abstract

This invention discloses a soft-start switch circuit for a battery-powered main circuit. The invention includes a MOSFET Q1, a resistor R1, a voltage divider resistor R2, and a capacitor C1. In the circuit, the two ends of capacitor C1 are grounded and connected to the gate of MOSFET Q1, respectively. The voltage divider resistor R2 is connected in parallel with capacitor C1, and the source of MOSFET Q1 is connected in series with resistor R1 and voltage divider resistor R2. This invention is simple to implement, low in cost, and improves the user experience while ensuring product quality.

Description

Technical Field

[0001] This utility model relates to the field of soft-start switch circuit for battery-powered main circuits. More specifically, it relates to a soft-start switch circuit for battery-powered main circuits. Background Technology

[0002] Current technology can achieve a soft-start mode on the battery-powered main circuit, but the soft-start time is not fixed for different battery voltages, mainly determined by the ratio of resistance to capacitance in the circuit. For different battery voltages, the resistance-to-capacitor ratio needs to be adjusted to regulate the soft-start time. The drawback of this circuit is that the soft-start time is not fixed; if this circuit is used in a circuit with a different battery voltage, simulation and debugging need to be redone. Utility Model Content

[0003] The technical problem to be solved by this utility model is to prevent the instantaneous current from being too large at the moment the main system is powered on, which could damage the subsequent circuits. Therefore, a soft-start switch circuit for battery-powered main circuits is provided.

[0004] This utility model discloses a soft-start switch circuit for a battery-powered main circuit, which is implemented by the following technical solution, including a MOSFET Q1, a resistor R1, a voltage divider resistor R2, and a capacitor C1; in the circuit, the two ends of the capacitor C1 are grounded and the gate of the MOSFET Q1, respectively; the voltage divider resistor R2 is connected in parallel with the capacitor C1, and the source of the MOSFET Q1 is connected in series with the resistor R1 and the voltage divider resistor R2 in sequence.

[0005] Compared with the prior art, the beneficial effects of this utility model are:

[0006] By employing a MOSFET and resistors / capacitors for charging and discharging, the MOSFET switch is slowly turned on, reducing the large current surge at power-on. The triggering switch utilizes the characteristics of capacitor charging; when the battery is inserted, the MOSFET slowly turns on, preventing a large current from flowing into the subsequent circuitry at the moment of battery insertion. This device is simple to implement, low in cost, and improves the user experience while ensuring product quality. Attached Figure Description

[0007] Figure 1 This is the circuit diagram of this utility model. Detailed Implementation

[0008] To better understand the above-mentioned objectives, features, and advantages of this utility model, the present utility model will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. Many specific details are set forth in the following description to provide a thorough understanding of this utility model; the described embodiments are merely some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this utility model pertains. The terminology used in this specification of the utility model is for the purpose of describing particular embodiments only and is not intended to limit the utility model.

[0009] like Figure 1 As shown, a soft-start switch circuit for a battery-powered main circuit includes a MOSFET Q1, a resistor R1, a voltage divider resistor R2, and a capacitor C1. In the circuit, the two ends of the capacitor C1 are grounded and the gate of the MOSFET Q1, respectively. The voltage divider resistor R2 is connected in parallel with the capacitor C1, and the source of the MOSFET Q1 is connected in series with the resistor R1 and the voltage divider resistor R2.

[0010] The principle of this invention is as follows: A MOSFET Q1 is connected in series in the circuit. The switching of MOSFET Q1 is controlled by a voltage divider resistor R2. The voltage divider resistor R2 is connected in parallel with a capacitor C1. Due to the characteristics of capacitor C1, the voltage across capacitor C1 cannot change abruptly. At the instant of power-on, the voltage across capacitor C1 is 0. As capacitor C1 charges, the voltage across capacitor C1 approaches the voltage divider voltage, thereby turning on the MOSFET. This circuit can prevent a large amount of energy from flooding into the load circuit after the battery at the instant of power-on, thus protecting the downstream circuit.

[0011] The above description is only a preferred embodiment of the present utility model. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A soft start switching circuit for use on a battery powered main loop, characterized by, The circuit includes a MOSFET Q1, a resistor R1, a voltage divider resistor R2, and a capacitor C1. The two ends of the capacitor C1 are grounded and the gate of the MOSFET Q1, respectively. The voltage divider resistor R2 is connected in parallel with the capacitor C1, and the source of the MOSFET Q1 is connected in series with the resistor R1 and the voltage divider resistor R2.

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