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[on:]

Hi All,

I'm not sure what an inductor is, and what it does.  I copied part of a schematic (http://www.sparkfun.com/datasheets/Prototyping/LiPower-v11.pdf) to go into a development board that I have.  The part number of the inductor is CDRH3D28, and I can't find the component on Digikey.  The value that I'm suppose to find is 4.7uH, 1.2A.  The products that I find are 4.7uH, 1.68A, and 10uH, 1.18A.  Any help on which part I should get (or a different part on Mouser)?

Thanks,
Qtechknow

[Reply #1 on:]

https://www.google.com/search?q=inductor&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-GB:official&client=firefox-a

[Reply #2 on:]

Thanks.  Do you know which part that I should get from Mouser/Digikey?

[Reply #3 on:]

Page 16 of the TPS61200 data sheet discusses the inductor, in terms of uH needed and current carrying capability.
http://www.ti.com/lit/ds/symlink/tps61202.pdf

Digikey carries Wurth Electronics inductors, here's an example.
http://www.digikey.com/product-detail/en/744031004/732-1008-1-ND/1639069

[Reply #4 on:]

Thanks.  Do you know if they carry CDRH3D28 packages of them???

[Reply #5 on:]

I did not see that part number.
Mouser carries that line of inductors
http://www.mouser.com/Search/Refine.aspx?Keyword=CDRH3D28
4.7uH, 1.62A
http://www.mouser.com/ProductDetail/Sumida/CDRH3D28NP-4R7NC/?qs=yEEOfDmvQDU77q2h0sbBlhHsUZYK97TnefpkD7pYMBc%3d

[Reply #6 on:]

Thanks.  Do you think that 4.7uH, 1.62A is okay when SparkFun uses 4.7uH, 1.2A?

[Reply #7 on:]

Only you can answer that.

Put your operating requirements into Equations 3 and 4 on page 16 of the datasheet, and see what the result is.

I expect 4.7uH/1.62A would be fine.

[Reply #8 on:]

I'm using it in the same way that SparkFun is, so I think that it's alright with 4.7uH/1.62A.  Am I wrong?

Thanks!

[Reply #9 on:]

Only you can answer that.  Only you know what is being connected.
Posting a link to a schematic does not provide the operating paramaters you are using.

Have you seen the size of the TPS61200? Impossibly tiny with leads that are 0.5mm apart. You will need good soldering skills to install it on a board.

[Reply #10 on:]

Ok.  Thanks!  I'm going to solder the first few boards by hand (will be pretty hard), then go with solder stenciling.

[Reply #11 on:]

I would go with a stencil to start to make sure the solder paste ends up in the right spots.
www.proto-advantage.com has inexpensive single-chip stencils.
Make sure your layout includes vias under the part for cooling from the ground planes.

Ok.  Thanks!  I'm going to solder the first few boards by hand (will be pretty hard), then go with solder stenciling.