Will the LED flashlight damage if it is used for a long time to stabilize the voltage 4 5v

Of course, there is damage, and as long as it is used, there will be damage.

But if that's what you're talking about, the voltage regulation will damage the LED much less than the voltage that's greater!

However, LED bulbs have a very long lifespan, and as long as they are used normally, there is almost no need to think about damage.

Generally, the nominal LED service life is tens of thousands of hours, so under normal circumstances, as long as it is not an impact or too high voltage, the life of the LED can not be considered.

The flashlight is"Move"use, with regulated power supply can not"Move";LED light-emitting diode its luminous voltage volt or so, current 20 mA, with 3-4 in series, and then organize multiple parallel connections can be directly connected to the volt power supply to work, such as with volt stabilized power supply, in addition to inconvenience"Move"There will be no harm in using it!

The working voltage of the white LED light-emitting diode is about volt, as long as the current of each LED is controlled within 20 milliamps, it can be used stably for a long time. Generally, the LEDs in the LED flashlight are connected in parallel, and the current resistance may be limited, and the total current of the regulated power supply can be measured conditionally, divided by the number of LEDs, and the average single current can be obtained, which is less than 20mA is safe. If exceeded, a resistor current limit can be connected in series.

Absolutely. Of course, scientific things must be used scientifically in order to have a long lifespan.

For example, a domestic brand Lieyou flashlight S205 uses 1 Cree Q5 lamp bead, the manufacturer is nominally conservative, compared with the domestic, 120 lumens, 4 hours of continuous lighting, the service life of the bulb is more than 100,000 hours, in the current market Q5 is the most commonly used, the lighting effect is also good. Compared with domestic bulb flashlights, it is quite energy-saving, and has a long service life.

Hunter S205 is a high-power flashlight, how can it only have 20-25mA current, what you said 20-25mA is low-power, like the kind of D9C-1A, that is almost the same as a gift, it can only be said that the LED flashlight is very power-saving compared to the old-fashioned flashlight in the same brightness, but the current flashlight, such as the Hunter flashlight, his brightness is far more than the old-fashioned flashlight, so the power consumption is almost the same as the old-fashioned, only for us, the brightness is also a lot brighter; If you want to change a gear and make the brightness a little lower, it will save a lot of electricity, depending on your personal preference; A little humble opinion...

Power saving, long service life, because the current of LED is only 15-20mA

Of course, it saves power and has a long service life.

Power saving also depends on how much power it is. It is also very large. Compared to the original incandescent lamp, it is much more power-saving.

The Hunter Flashlight I use is super durable, and one 18650 can be used continuously for hours in strong light mode.

What is certain is that when the white LED tube emits light, it does add a 3V voltage to cover the mask. There is a special circuit inside the flashlight that uses the power supply. This circuit consists of a dedicated step-up IC (integrated circuit) that uses the principle of a switching circuit to efficiently raise the voltage to 3 V, which is required for LEDs.

The energy is conserved, and the conversion efficiency is generally about 80%, so the power supply needs at least twice the current compared to the 3V power supply stuffy state. In addition to using a smaller number of batteries, another advantage of using ICs is that they can maintain a more stable current.

The conversion efficiency of a good DCDC constant current source will be higher than that of having a resistor, because when you use a new battery, the voltage of 4 batteries will be there, then the voltage drop on your resistor will be about 3V, and then multiplied by the current on your LED is the power consumed by the resistor; Constant current sources will generally have an efficiency of 90%. It is recommended to use a constant current power supply.

That resistor is the current-limiting resistor

The current of the battery is large when the current is lowered by the resistor. You can't just look at the voltage, it's mainly the current.

It is best to use a special LED constant current IC for high-current LEDs, there are step-down types and step-up types, you can look for them.