Components selection

STLD20D

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characteristics can be negligible compared to the losses induced by the reverse current

7.4

The average output current is regulated by sensing a low external ohmic sensing resistor

7.5

Efficiency

Efficiency is a significant parameter for the application. The higher the efficiency, the longer

the life time of the battery. The efficiency is given by:

.

R

LED

V

FB

I

LED

-----------

0.3V

20mA

----------------

15

Ω

7

[]

=

=

=

Efficiency

P

output

P

input

-------------------

NV

LED

I

LED

⋅

⋅

V

IN

I

input

⋅

--------------------------------------------

8

[]

=

=