RE: [SI-LIST] : Any standards of the derating of Capacitors,Resit ors, and inducto rs?

About this list Date view Thread view Subject view Author view

From: L· (John@quantatw.com)
Date: Sun Mar 25 2001 - 19:50:53 PST


Dear Steve,
Could you please suggest how to derive the equation, you show below?
 
Series R power = ( ( Vswing / 2 ) ^ 2 / Rterm ) * Tflight * Symbol_rate. (
2 * Tflight cancels Symbol_rate / 2 )

Does somebody have any clues about the derivation of the equation?
 
Thank you for your comments.
 
 
Best Regards,

John Lin
Senior SI Engineer, Server Team, ARD4
Quanta Computer Inc.,Taiwan, R.O.C.
Email: John@quantatw.com
Tel: 886+3+3979000 ext. 5183

-----Original Message-----
From: S. Weir [mailto:weirsp@atdial.net]
Sent: Monday, March 19, 2001 4:47 PM
To: John Lin (L·)
Subject: Re: [SI-LIST] : Any standards of the derating of
Capacitors,Resitors, and inducto rs?

There are, but it depends primarily on the material and method of
construction. For example, tantalum capacitors voltage deratings are
typically 50%. You will have to get the data from the component mfg's that
you are qualifying.

Damping resistor power calculations depend on the circuit configuration.
For series termination schemes:

Series R power = ( ( Vswing / 2 ) ^ 2 / Rterm ) * Tflight * Symbol_rate. (
2 * Tflight cancels Symbol_rate / 2 )

Regards,

Steve.

At 03:46 PM 3/19/01 +0800, you wrote:

Dear SI gurus,
 
Are there any industrial standards for derating of capacitors and resistors,
as well as inductors?
 
For example, a capacitor rated as 10V, what shall be the proper operating
voltage applied to this capacitor in term of reasonable voltage stress
ratio? As we know, the higher operating voltage will cause lower MTBF (Mean
Team Between Failure). Thus, lower the reliability of products. However,
using higher rated capacitor will increase cost of products. The same things
happen to resistors and inductors.
 
Talking about the damping resistors, how do we calculate the power consuming
on them so that we can calculation power stress ratio, operating power
divided by rated power?
 
 
 
Thank you for your helps in advance.

John Lin
Senior SI Engineer, Server Team, ARD4
Quanta Computer Inc.,Taiwan, R.O.C.
Email: John@quantatw.com
Tel: 886+3+3979000 ext. 5183
 

**** To unsubscribe from si-list or si-list-digest: send e-mail to
majordomo@silab.eng.sun.com. In the BODY of message put: UNSUBSCRIBE
si-list or UNSUBSCRIBE si-list-digest, for more help, put HELP.
si-list archives are accessible at http://www.qsl.net/wb6tpu
****


About this list Date view Thread view Subject view Author view

This archive was generated by hypermail 2b29 : Thu Jun 21 2001 - 10:11:19 PDT