1. Use transient voltage suppression diodes (TVS for short)
Transient voltage suppression LED is a high-efficiency maintenance equipment of the LED method. When its north and south poles are subjected to a reverse transient high-energy impact, it can reduce the high resistance between the north and south poles to low resistance at a speed of 10 minus 12th power for a short time, and absorb up to several kilowatts. The surge power clamps the voltage between the north and south poles to a predetermined voltage value, which effectively maintains the fine components in the electronic circuit. Transient voltage suppression diodes have the advantages of fast care time, high transient power, low leakage current, good breakdown voltage error consistency, easier control of the clamping voltage, no damage limit, and small size.
2. Choose a fuse (tube) in the maintenance circuit
Because the fuse is one-time, and the response speed is slow, the function is poor, and the operation is troublesome, so the fuse is not suitable for LED lighting products, because the LED lamp is now mainly used in the glorious project and the lighting project in the city. It requires the LED lamp bead maintenance circuit to be very strict: when the normal operating current is exceeded, the maintenance can be initiated immediately, so that the power supply path of the LED is disconnected, so that the LED and the power supply can be maintained, and it can take the initiative after the entire lamp is normal. Resuming the power supply will not affect the LED operation. The circuit should not be too messy, not too big, and the cost is even lower. Therefore, the method of selecting a fuse is very difficult to end.
3. Choose a self-recovery fuse
Self-recovery fuse, also known as polymer positive temperature thermistor PTC, is composed of polymer and conductive particles. After special processing, the conductive particles form a chain-like conductive path in the polymer. When the normal operating current passes (or the component is at normal ambient temperature), the PTC resettable fuse is in a low resistance state; when there is abnormal overcurrent in the circuit (or the ambient temperature rises), the large current (or the ambient temperature rises) The generated heat makes the polymer active and expand, which cuts off the conductive path formed by the conductive particles. The PTC resettable fuse is in a high-resistance state; when the overcurrent (over-temperature condition) in the circuit disappears, the polymer cools and the volume When it returns to normal, the conductive particles form a conductive path from the beginning, and the PTC resettable fuse assumes an initial low resistance state. In normal operating conditions, the self-recovering fuse generates very little heat, and in abnormal operating conditions, its heat is very high and the resistance value is large, which restricts the current passing through it, and then plays a maintenance role. In the detailed circuit, you can choose: branch maintenance. Generally, high-power deep-ultraviolet LED lamp beads are divided into many branches in series. We can add a PTC component in front of each branch for maintenance. The benefits of this method are high accuracy, good maintenance reliability, and overall maintenance. Add a PTC component in front of all the light beads to maintain the entire lamp. The benefit of this method is simple and does not take up volume.
