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Author Topic: dimming leds with tip122 and voltage variable  (Read 859 times)
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Im trying to dimming two LEDs in parallel with a power supply of 3-48V variable and 1.4A constants with a TIP122. If I use a 3.7V battery I have no problems, but the supply give me 48V and tip begins heating extremely, but leds only needs 3V. This is like transistor demands all power capacity. Im using a 2k2 resistor on the base.
any idea? thanks

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