Precision metal film resistors

[Andre Majorel]

What is the difference between 0.1% and 1% metal film resistors ?
Are the higher precision parts made from a different process ?
Or cherry picked from a big batch of 1% ? Just curious.

--
André Majorel <URL:http://www.teaser.fr/~amajorel/>
(Counterfeit: akomyn@uninominal.com fytoqaj@abrell.satisfactionworld.com)
"I drink, I smoke, I gamble, I chase girls--but postal chess is
one vice I don't have." -- Mikhail Tal

 

[Peter A Forbes]

On Sat, 2 Feb 2008 09:35:32 +0000 (UTC), Andre Majorel <cheney@halliburton.com>
wrote:

What is the difference between 0.1% and 1% metal film resistors ?
Are the higher precision parts made from a different process ?
Or cherry picked from a big batch of 1% ? Just curious.

Different process looking at some here. They are physically different in
construction and finish.

We use 1% or 2% MFR generally, having ditched CFR a few years back. We have a
few stock 1% for special needs.

Peter
--
Peter & Rita Forbes
Email: diesel@easynet.co.uk
http://www.oldengine.org/members/diesel
http://www.stationary-engine.co.uk

 

[Mook Johnson]

"Andre Majorel" <cheney@halliburton.com> wrote in message
news:slrnfq8eb2.vtp.cheney@atc5.vermine.org...

What is the difference between 0.1% and 1% metal film resistors ?
Are the higher precision parts made from a different process ?
Or cherry picked from a big batch of 1% ? Just curious.

I think most are laser etch trimmed to .1%.

 

[Spehro Pefhany]

On Sat, 2 Feb 2008 09:35:32 +0000 (UTC), the renowned Andre Majorel
<cheney@halliburton.com> wrote:

What is the difference between 0.1% and 1% metal film resistors ?
Are the higher precision parts made from a different process ?
Or cherry picked from a big batch of 1% ? Just curious.

Different process, at least in most cases. Compare tempco, load life
and other stability figures to see. A 1% resistor that happens to be
within 0.1% will usually not have the stability that many designers
are looking for.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

 

[Andre Majorel]

On 2008-02-04, Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> wrote:

On Sat, 2 Feb 2008 09:35:32 +0000 (UTC), the renowned Andre Majorel
cheney@halliburton.com> wrote:

What is the difference between 0.1% and 1% metal film resistors ?
Are the higher precision parts made from a different process ?
Or cherry picked from a big batch of 1% ? Just curious.

Different process, at least in most cases. Compare tempco, load life
and other stability figures to see. A 1% resistor that happens to be
within 0.1% will usually not have the stability that many designers
are looking for.

Thanks everyone that was informative. I had noticed the lower
tempcos but not the other parameters.

--
André Majorel <URL:http://www.teaser.fr/~amajorel/>
(Counterfeit: ydanof@coax.org inafyx@mathews.com)
"I drink, I smoke, I gamble, I chase girls--but postal chess is
one vice I don't have." -- Mikhail Tal