| Author |
Message |
kasirajang
Joined: 06 Mar 2007
Posts: 39
|
 30 Mar 2007 6:50 decoupling capacitor calculation |
|
|
|
|
How to calculate the Bypass capacitor & Decoupling capacitor values while designing?
* people are using 0.1uF, 0.01uF in most of the places...is it a standard value?
* or values are chosen based on the Thumb rule..? or it's based on the chip operating frequency?
Can any one explain it..? or suggest me some article which describes..
|
|
| Back to top |
|
 |
IanP
Joined: 05 Oct 2004
Posts: 6490
Helped: 1542
Location: West Coast
|
30 Mar 2007 7:13 bypass capacitor calculation |
|
|
|
|
Here is an ineresting article on this issue:
"BYPASS CAPACITOR SELECTION FOR HIGHSPEED DESIGNS"
http://download.micron.com/pdf/technotes/TN0006.pdf
.. you will learn how to estimate values of these caps ..
Now, the "100nF" value ..
If your estimation shows that you need, for example, 65nF .. wouldn't you use the cheapest and the most common cap =>100nF ???
Regards,
IanP
|
|
| Back to top |
|
|
Google
AdSense
|
30 Mar 2007 7:13 Ads |
|
|
|
|
|
|
| Back to top |
|
|
MSSN
Joined: 08 Mar 2006
Posts: 232
Helped: 26
|
30 Mar 2007 19:33 bypass capacitor calculator |
|
|
|
|
| r u asking about on-board decoupling caps or on-chip decoupling caps??
|
|
| Back to top |
|
|
tlihu
Joined: 02 Jan 2002
Posts: 669
Helped: 5
|
31 Mar 2007 2:37 decoupling capacitor selection |
|
|
|
|
| I'm more intererted in how to calculate the bypass/decoupling capacitance on chip. Is there any article?
|
|
| Back to top |
|
|
rlerner
Joined: 03 Apr 2007
Posts: 1
|
03 Apr 2007 13:25 calculate decoupling capacitor |
|
|
|
|
There are many factors to take into account when calculating decoupling and bypass capacitor values. There is a good app note from Texas Instruments that you can use as a guide.
Refer to the following link for information on calculating cut off frequencies:
http://focus.ti.com/general/docs/techdocsabstract.tsp?abstractName=scaa048
(I noticed that this posting strips out the "tt" from the URL so you may need to add it back in where http is listed in the above URL
This can also be found at the ti.com website and searching for scaa048
Hope this helps
|
|
| Back to top |
|
|
