printable circuit board?

Question

I'm looking to make a small device that will take 5V power from a USB power source and charge a 3.7v lithium battery with at least several hundred mA of current.. For that, I would need a circuit board that regulates the voltage and switches off the current when the battery is fully charged. 

I'd like to try and get all the required circuitry to as close to 1mm in thickness as possible. 
I am aware that pcbs can get as thin as 0.15mm. I'm curious as to what a realistic thickness would be with a charge controller IC attached as someone has told me that that would be the limiting factor.

Is http://www.mouser.com/ProductDetail/Fair… a charge controller? It doesn't seem like they get really thick.

Thanks.

Violet W · Accepted Answer

Your link is broken... What type of lithium battery?

You might check Microchip.  Here's a design ap note from 2005.
http://ww1.microchip.com/downloads/en/appnotes/00971a.pdf

The chips are available with a 3-week lead time.
http://www.mouser.com/_/?Keyword=mcp73853&FS=True
http://www.mouser.com/Semiconductors/Power-Management-ICs/Battery-Management/_/N-wnwk?Keyword=mcp73855&FS=True

Section 7 has the packaging information:  http://ww1.microchip.com/downloads/en/DeviceDoc/21915a.pdf
The chip is nominally 0.90 mm high, so with PCB the overall thickness will exceed 1mm.

But this is an old design.  Poke around on Microchip's web site to see if there is a newer design with a thinner package.

EDIT:  Here's a design from 2008.  Still 0.90 mm:
http://www.sparkfun.com/datasheets/Prototyping/Batteries/MCP73831T.pdf
However, you can get a kit here in case you want to see how someone else did it:
https://www.sparkfun.com/products/9876

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printable circuit board?

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