[SI-LIST] : Trace Capacitance
Farrokh Mottahedin (Farrokh.Mottahedin@quantum.com)
Mon, 21 Jun 1999 08:59:22 -0700
I hope someone can explain what is happening with the following capacitance
measurement. A friend asks if capacitance is directly proportional to
surface area, why doesn't his measurement scale linearly. On a pcb made
specifically for trace characteristics measurement, he measures
1) 10 pf for a 10 cm long trace that is 5 mils (.12 mm) wide
2) 25 pf for a 10 cm long trace that is 20 mils (.50 mm) wide
3) Both traces are far apart from each other and from other components.
4) Both traces are over a solid ground plane.
5) Equipment is HP 4285A Precision LCR meter set at 1 MHz
Thanks,
Farrokh Mottahedin
Quantum Corporation
(408) 324-7934
farrokh.mottahedin@quantum.com
**** To unsubscribe from si-list: send e-mail to majordomo@silab.eng.sun.com. In the BODY of message put: UNSUBSCRIBE si-list, for more help, put HELP. si-list archives are accessible at http://www.qsl.net/wb6tpu/si-list ****