Massimo Gaggero <massimo.gaggero@gmail.com> wrote:
> Hi all,
>        looking for a cheap and easy to use DC Step-Down Step-Up Converter=
 to =20
> 3.3V, I found this:
>
> https://www.banggood.com/3Pcs-Mini-2-in-1-DC-Step-Down-Step-Up-Converter-=
1_8V-5V-to-3_3V-Power-For-Arduino-p-1205021.html
> that fits very well to my project.
>
> But searching for more details about the IC, the only clue is the
> silkscreen 'N1IF', from which I cannot trace back to a datasheet.
> Googling around I found this ad
>
> https://www.yoycart.com/Product/542865822576/
>
> claiming the 'N1IF' IC to be a "hx4002b" charge pump. But again, no
> datasheet for "hx4002b" charge pump.
>
> Does anybody of you have seen or used this before?

    The "b" may be only a tolerance suffix appended to a "hx4002" part.
Did you see the hx4002 datasheet shown below? The recommended layout
shown on page 9 of that datasheet seems at least superficially identical
to the banggood image.

url=3Dhttp://www.hxsemi.com/upfiles/20141031121620.pdf

Thank you,

--=20
Don Kuenz, KB7RPU

Genius is nothing but a greater aptitude for patience. - de Buffon

--=20
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