Lantern with 3 leds (reverse engineering)
I buy a chinesse lantern with 3 leds who is powered by 2 AA bateries. If power directlly a white led at 2 AA bateries, led will lit very low or not lit, but if it use PWM style or any impulse, can lit the led.
I made reverse engineering of lantern…
I use a oscilloscope for see the signal on the leds:
and on lab power suply I see the consum little different like with bateries (0,17A on batterise and 0,32A with lab power supply):
I redesigned the schematic using Livewire software: