Li Battery Voltage Boosting Circuit for 4 LEDs
Basic circuit using a 5.1 KΩ Base resisitor
The basic circuit used the standard best loops ration 8 by 20 loops on the
toroid and was powered by a Li 18650 battery starting at ~ 4.2V.
Rebuilt circuit using a 5.1 KΩ Base resisitor
The rebuilt circuit used the same 8 by 20 turns on the toroid but instead of
using a Li battery starting at ~ 4.2V it was using a DC power supply of about
Rebuilt circuit using a 10 KΩ Base resisitor
The peak voltage when using a 10 KΩ resistor was observed to be anything
from 16.6 to 17.2 Volts.
The rebuilt circuit, using either resistor, shows a slightly longer off time
to the on time. The original "basic" circuit showed an on/off time ratio of 1
to 2, the rebuilt circuit shows the ratio as 1 to 2.5 so approximately 25%
more off time. I think this is beacuse for the "basic" version I used a
pre-wound toroid I had in the drawer so I don't know the loop ratio for that
version but for the "rebuilt" version I know I used the best ratio of 8 to 20
On the other hand, the difference may simply be that I tested the "basic"
version using 4.2V and the "rebuilt" version using ~3.75V since the power
supply to be used for this circuit was known to be running at 3.76V.
Circuit board Above View
Circuit board Below View
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