I don't use these to build chargers but to transform old flashlights that use big expensive 4.5 batteries to LED flashlights that can work with one or 2 normal AA batteries. I thought that I have to use a resistor between the output of the DC-DC unit and the LED, but the LED works well without such resistor. I recover the LED ships from dead LED bulbs. I noticed that when a bulb dies, it is often because that one or few LEDs died. The other LEDs on the bulb still OK. Not easy to unsolder and re-solder such small smd LEDs but you can do it with time I haven't tested all 5 modules but the 2 I used worked well. Notice that when the module is alimented by only one AA battery at the input, the red LED does not work and still off

I don't use these to build chargers but to transform old flashlights that use big expensive 4.5 batteries to LED flashlights that can work with one or 2 normal AA batteries. I thought that I have to use a resistor between the output of the DC-DC unit and the LED, but the LED works well without such resistor. I recover the LED ships from dead LED bulbs. I noticed that when a bulb dies, it is often because that one or few LEDs died. The other LEDs on the bulb still OK. Not easy to unsolder and re-solder such small smd LEDs but you can do it with time I haven't tested all 5 modules but the 2 I used worked well. Notice that when the module is alimented by only one AA battery at the input, the red LED does not work and still off

I don't use these to build chargers but to transform old flashlights that use big expensive 4.5 batteries to LED flashlights that can work with one or 2 normal AA batteries. I thought that I have to use a resistor between the output of the DC-DC unit and the LED, but the LED works well without such resistor. I recover the LED ships from dead LED bulbs. I noticed that when a bulb dies, it is often because that one or few LEDs died. The other LEDs on the bulb still OK. Not easy to unsolder and re-solder such small smd LEDs but you can do it with time I haven't tested all 5 modules but the 2 I used worked well. Notice that when the module is alimented by only one AA battery at the input, the red LED does not work and still off

ottimo oggetto per poter elevare la tensione da 1 volt fino a 5 volt totali

ottimo oggetto per poter elevare la tensione da 1 volt fino a 5 volt totali

ottimo oggetto per poter elevare la tensione da 1 volt fino a 5 volt totali