Jumper to replace Inductor

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I want to use a linear regulator on a board where a buck switcher had  
been designed in.  No problem on the chip, there are thousands with a  
compatible footprint for this TSOP-5 package.  I need to replace the  
inductor with a jumper, something that can be SMT assembled and of  
course, inexpensive.

The pads are spaced so a 1206 would reach but it is a bit wide with the  
pads only 47 mils wide.  More importantly there are vias about 15 mils  
away which end up maybe 7 or 8 mils away with the wider part overhang.  
I'm a little concerned with this spacing.  An 0805 part would fit the  
pads better, but doesn't quite reach the gap of 82 mils.

I was searching for zero ohm resistors, but it occurred to me there may  
be parts specifically designed as jumpers which might fit these pads  
better.  Anyone know of anything like this?  Nearly any jumper of 110 to  
120 mils long and no more than 50 mils wide would do, better is 35 or 40  
mils wide.

I did find this which is a bit more than resistors at $450 per reel.

http://www.digikey.com/product-detail/en/harwin-inc/S1911-46R/952-1740-1-ND/3131071

If the assembly house doesn't like the 1206 resistor, it wouldn't be the  
worst thing...

--  

Rick C

Re: Jumper to replace Inductor
On 30/06/2016 16:26, rickman wrote:
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1206 on its side?  That'll confuse them.

Cheers
--  
Syd

Re: Jumper to replace Inductor

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  A  test point.  Typically Silver Plated Copper or Tin plated Copper,
but more often Silver as it takes solder better.

http://www.digikey.com/product-detail/en/harwin-inc/S1751-46R/952-1478-2-ND/2264459

Re: Jumper to replace Inductor
On Thu, 30 Jun 2016 14:27:53 -0400, DecadentLinuxUserNumeroUno

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  So, you are ignoring the test point suggestion?

  Any time you need to replace a part already laid out with a jumper,
you can use a test point.

  Two benefits...

    A: It is usually cheaper than a zero ohm resistor of the same form
factor, and

    B:  They are available of tape and reel and are pick and place
compatible if you get the right type.

  Three if you count the fact that you can also actually use it as a
test point.

Re: Jumper to replace Inductor
On 6/30/2016 5:45 PM, DecadentLinuxUserNumeroUno wrote:
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Not ignoring it, but this part is the same if not bigger than the 1206  
resistor I am looking at.  The other Harwin test points are the same  
size as 0805 and 0603 resistors which are too small.

However... I took another spin through  the Digikey list of test points  
and found one by Keystone, the 5015 which is just the right size...  
Goldilocks!  But this is hardly cheaper than the resistor jumper.  Those  
are a fraction of a penny and this is a quarter even at qty 500.  Not a  
big deal, but certainly not cheaper... maybe cheaper than the inductor,  
but not by lots!  I wonder why a small piece of metal is a quarter???  
Does it really cost so much more to make than an SMD resistor?

--  

Rick C

Re: Jumper to replace Inductor

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  It is presicion cut and formed and plated metal.

  I think I was thinking of and referring to a precision zero ohm
resistor.

  Even the wrong form factor will self center on the pads from the
solder meniscus, unless the irregularity is extreme.

  I just picked one.  The one we use is different, and I never even
glanced at the price.

  I know ordinary resistors are cheaper.

Re: Jumper to replace Inductor

resistor.  

0 ohms +- 1% ?

;)

Cheers

Phil Hobbs

Re: Jumper to replace Inductor
Gave us:


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  No...  that is standard level.  Cheap.  At 0.1% they get a bit more
pricey.

  Resistors are made by the billions.  Test points maybe in the millions
per year.

 A lot less perfected and optimized manufacturing method and more costly
finished product, and likely a higher QA fail rate.  Higher price
result.

Re: Jumper to replace Inductor
On Friday, July 1, 2016 at 7:07:35 AM UTC-4, Phil Hobbs wrote:

  
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Almost always [0..+oo%].  They cherry-pick the others for military use.

Cheers,
James Arthur

Re: Jumper to replace Inductor
On 7/1/2016 7:07 AM, Phil Hobbs wrote:
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No need for that sort of accuracy.  I'm not using it for its resistance,  
it's just a jumper....  ;)

--  

Rick C

Re: Jumper to replace Inductor
On 1/07/2016 9:07 PM, Phil Hobbs wrote:
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1% of zero is still zero, so its perfectly precise ?!?!?

Re: Jumper to replace Inductor
wrote:

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But why would you pay a premium for a 1% 0-ohm resistor, over a 5%?

Re: Jumper to replace Inductor
On Fri, 01 Jul 2016 22:57:48 -0400, snipped-for-privacy@attt.bizz Gave us:

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  Are you asking him, yourself, or the group?

Re: Jumper to replace Inductor
On Sat, 02 Jul 2016 02:34:33 -0400, DecadentLinuxUserNumeroUno

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Only you would be stupid enough to even ask that question,
AlwaysWrong.

Re: Jumper to replace Inductor
us:

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  You do not seem to understand resistors much.

  It is rarely ever actually zero.  Even the best conductor (Silver) has
a known resistance for a known transition length.  Therefore the
accuracy will determine just how close to true zero it will be and in a
batch quantity for circuit function repeatability.



Re: Jumper to replace Inductor
On 7/2/2016 1:33 AM, DecadentLinuxUserNumeroUno wrote:
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You do not seem to understand the number zero much. Look at your IQ for  
a hint.

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Then zero ohm resistors are a big lie. They cannot be had.



Re: Jumper to replace Inductor

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  You do not seem to understand that there is no zero ohm passage short
of a superconductor.

  So ALL "zero ohm" resistors are NOT zero ohms.  And the precision
level is there to declare how closely matched entire batches of them
will be.

  You fail on the common sense element, yet you attack my IQ.
You're brilliant, dipshit...   NOT!

Re: Jumper to replace Inductor
On 7/2/2016 10:42 AM, DecadentLinuxUserNumeroUno wrote:
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What the hell does that mean? Are PCB board zero ohm devices made of  
some sort of superconductor?

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To what? Zero? To the next one on the tape? To a 10K resistor? So,  
again, what is the precision level of zero?

What is the dB of 1? How about 23?

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Attack? No, it is on display for everyone to see.



Re: Jumper to replace Inductor

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  Go away, little girl.

Re: Jumper to replace Inductor
On 7/2/2016 10:42 AM, DecadentLinuxUserNumeroUno wrote:
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What is the difference in a duck?

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