On Fri, 28 Oct 2011 18:37:15 +0800, the renowned Man-wai Chang
wrote:


Is there such a toy?

You could use this simple circuit to work down to 1V --


FB = OUT for Red

FB = GND for Green/Blue/White
|
.----------.
Vin 0.8V minimum | FB |
10uH | |
___ | L6920 | LED
o----+---UUU----|LX OUT|----+-|---+
+ | | | | |
--- | | | |
--- | REF | | .-.
47uF | '----------' | | |
| | + | |
GND 100n --- --- '-'
--- 47uF --- |
| |
GND GND GND


All the parts can be tiny SMT components. Reduce the 47uF caps to 22uF
and use 0805 22uF/6.3V ceramics and an 0805 inductor to reduce size,
and the 100n can be an 0402.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
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