Self-adaptive polarity high-current output circuit

Abstract

The utility model discloses a self-adaptive polarity high-current output circuit, which comprises a high-voltage signal output circuit and an output line fault detection circuit, and effectively isolates a high-voltage circuit and a low-voltage circuit of the output circuit by utilizing the switching action of a novel optocoupler. When the short circuit fault of the circuit is caused by severe use environment and the like, the current passing through the Darlington tube is increased instantly, so that the resettable fuse acts in time to cut off the circuit, and the effect of protecting components in the circuit is achieved; after the resettable fuse is cooled, the circuit is switched on, the coil type device can work normally, the circuit can be used normally in a severe environment, even if a fault occurs, the circuit can still work normally after being cooled, and the device in the circuit is effectively prevented from being damaged. The circuit is applied to a welding power supply, so that the maintenance cost is reduced, and the use stability and reliability of an electric welding machine are improved.

Description

Technical Field

[0001] The utility model relates to the technical fields of logistics transmission, etc., and specifically is a high-current output circuit with adaptive polarity. Background Art

[0002] The current input circuit or current output circuit is generally coupled to a constant current source at the front end and connected to a load (resistance or capacitance) at the back end to provide a constant current output or input for resistance measurement and capacitance measurement, etc. The reason why the low-power circuit has low working circuit energy consumption (mostly milliampere level) is that it works in a specific working environment and cannot provide a large current for work; in addition, since the energy supply is a non-sustainable energy source, it cannot meet the need to provide a large current; therefore, based on the above two energy supply limited conditions, the low-power circuit cannot meet the instantaneous high power consumption requirements.

[0003] For example, the Chinese utility model patent application number CN201520895573.5 discloses "An instantaneous large current output circuit in a low-power circuit", which sets a threshold voltage by using a voltage clamping energy storage module to store energy below the threshold voltage, and the energy above the threshold voltage is stepped down and stored by a step-down and voltage-stabilizing output energy storage module before being output through a threshold voltage output module; when the threshold voltage output module continuously outputs and the output current is large, causing the output voltage of the step-down and voltage-stabilizing output energy storage module to decrease, the step-down and voltage-stabilizing output energy storage module uses its internal energy storage to provide instantaneous supply to the threshold voltage output module; the instantaneous large current output circuit in a low-power circuit provided by the embodiment of the utility model can meet the circuit working requirements of a low-power circuit supplying a large current and instantaneous high power consumption.

[0004] However, the general structure of the adaptive polarity high current output circuit is relatively complicated. From the perspective of maintenance cost, the damage to the welding power supply due to component short circuit failure is not worth the cost. In addition, frequent business trips to deal with such problems will form a bad inherent impression on customers and affect subsequent sales. Utility Model Content

[0005] 1. Technical issues to be resolved

[0006] In view of the deficiencies of the prior art, the utility model provides a high current output circuit with adaptive polarity, which solves the above-mentioned problems.

[0007] (II) Technical solution

[0008] To achieve the above objectives, the utility model is implemented through the following technical solutions: an adaptive polarity high current output circuit, including a rectifier diode D3, a rectifier diode D4, a resistor R26, a resistor R28, a capacitor C15, a resettable fuse PTC2, an NPN transistor Q2, an NMOS tube Q16 and an optocoupler PC3, the base of the NPN transistor Q2 is electrically connected to the 3-pin of the optocoupler PC3, the collector of the NPN transistor Q2 is electrically connected to the resettable fuse PTC2, the rectifier diode D3 and the rectifier diode D4 are bridged between the collector and the emitter of the NPN transistor Q2, the other end of the rectifier diode D3 is connected to the FO fault output, and the other end of the rectifier diode D4 is connected to C0M1.

[0009] Preferably, pin 4 of the optocoupler PC3 is electrically connected to the collector of the NPN transistor Q2, pin 1 of the optocoupler PC3 is electrically connected to the drain of the NMOS tube and the resistor R26, the other end of the resistor R26 is connected to 3.3V, and pin 2 of the optocoupler PC3 is connected.

[0010] Preferably, the gate of the NMOS tube Q16 is electrically connected to the resistor R27, the resistor R28, and the capacitor C15, the other ends of the resistor R28 and the capacitor C15 are grounded, the other end of the resistor R27 is connected to the MCU, and the source of the NMOS tube Q16 is grounded.

[0011] (III) Beneficial effects

[0012] The utility model provides a high-current output circuit with adaptive polarity. It has the following beneficial effects: including a high-voltage signal output circuit and an output line fault detection circuit, by utilizing the switching action of a new type of optical coupler, the high-voltage circuit and the low-voltage circuit of the output circuit are effectively isolated, when a short-circuit fault occurs in the circuit due to a bad use environment and other reasons, the current passing through the Darlington tube will increase instantly, so that the self-resetting fuse will act in time, disconnect the circuit, and play a role in protecting the components in the circuit; after the self-resetting fuse cools down, the circuit is connected, and the components can work normally. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the circuit structure flow of the utility model.

[0014] In the figure: rectifier diode D3, rectifier diode D4, resistor R26, resistor R27, resistor R28, capacitor C15, resettable fuse PTC2, NPN transistor Q2, NMOS tube Q16, optocoupler PC3. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0016] See also Figure 1 The utility model provides a technical solution for an adaptive polarity high current output circuit: an adaptive polarity high current output circuit, comprising a rectifier diode D3, a rectifier diode D4, a resistor R26, a resistor R28, a capacitor C15, a resettable fuse PTC2, an NPN transistor Q2, an NMOS tube Q16 and an optocoupler PC3, the base of the NPN transistor Q2 is electrically connected to the 3rd pin of the optocoupler PC3, the collector of the NPN transistor Q2 is electrically connected to the resettable fuse PTC2, the rectifier diode D3 and the emitter of the NPN transistor Q2 are connected across the collector Rectifier diode D4, the other end of rectifier diode D3 is connected to FO fault output, the other end of rectifier diode D4 is connected to C0M1, pin 4 of optocoupler PC3 is electrically connected to the collector of NPN transistor Q2, pin 1 of optocoupler PC3 is electrically connected to the drain of NMOS tube and resistor R26, the other end of resistor R26 is connected to 3.3V, pin 2 of optocoupler PC3 is connected, the gate of NMOS tube Q16 is electrically connected to resistor R27, resistor R28, and capacitor C15, the other end of resistor R28 and capacitor C15 is grounded, the other end of resistor R27 is connected to MCU, and the source of NMOS tube Q16 is grounded.

[0017] When in use, when the MCU-FO signal is low, the NMOS tube Q16 is not turned on, and the 3.3V current flows into the 1st pin of the optocoupler PC3 through the circuit, and is forward-conducted by the light-emitting diode, the internal LED emits light, the photosensitive transistor is illuminated by light, and the FO is powered externally. The 3rd and 4th pins of the optocoupler PC3 are connected, and the emitter junction E of the transistor Q2 is turned on, which is an open-drain output. The transistor is equivalent to a switch. The 3rd pin signal of the optocoupler PC3 flows to the base of the transistor Q2, the transistor Q2 is turned on, and FO is pulled low. Conversely, when the MCU-FO signal is high, the optocoupler is not connected, and FO is high.

[0018] The control method of the present invention is to control by manually starting and closing the switch. The wiring diagram of the power element and the provision of power supply are common knowledge in the field, and the present invention is mainly used to protect mechanical devices, so the present invention will not explain the control method and wiring arrangement in detail.

[0019] The control method of the present invention is automatic control through a controller. The control circuit of the controller can be realized by simple programming by technicians in this field. The provision of power is also common knowledge in this field. The present invention is mainly used to protect mechanical devices, so the present invention will no longer explain the control method and circuit connection in detail.

[0020] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An adaptive polarity high current output circuit, comprising a rectifier diode D3, a rectifier diode D4, a resistor R26, a resistor R28, a capacitor C15, a self-recovery fuse PTC2, an NPN transistor Q2, an NMOS transistor Q16 and an optocoupler PC3; Features: The base of the NPN transistor Q2 is electrically connected to pin 3 of the optocoupler PC3, the collector of the NPN transistor Q2 is electrically connected to the resettable fuse PTC2, a rectifier diode D3 and a rectifier diode D4 are connected between the collector and the emitter of the NPN transistor Q2, the other end of the rectifier diode D3 is connected to the FO fault output, and the other end of the rectifier diode D4 is connected to C0M1.

2. The high current output circuit with adaptive polarity according to claim 1, characterized in that: Pin 4 of the optocoupler PC3 is electrically connected to the collector of the NPN transistor Q2, pin 1 of the optocoupler PC3 is electrically connected to the drain of the NMOS tube and the resistor R26, the other end of the resistor R26 is connected to 3.3V, and pin 2 of the optocoupler PC3 is connected.

3. The high current output circuit with adaptive polarity according to claim 1, characterized in that: The gate of the NMOS tube Q16 is electrically connected to the resistor R27, the resistor R28, and the capacitor C15. The other ends of the resistor R28 and the capacitor C15 are grounded. The other end of the resistor R27 is connected to the MCU. The source of the NMOS tube Q16 is grounded.

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