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Entry  Tue Aug 23 17:05:20 2016, Praful, Update, Electronics, Soldered Circuit Working 10x
    Reply  Tue Aug 23 22:58:16 2016, Koji, Update, Electronics, Decoupling capacitor 101 
       Reply  Wed Aug 24 14:44:33 2016, Praful, Update, Electronics, Decoupling capacitor 101 
          Reply  Wed Aug 24 19:37:55 2016, Koji, Update, Electronics, Decoupling capacitor 101 
Message ID: 12435     Entry time: Tue Aug 23 22:58:16 2016     In reply to: 12433     Reply to this: 12437
Author: Koji 
Type: Update 
Category: Electronics 
Subject: Decoupling capacitor 101 

What I suggested was:
- For most cases, power decoupling capacitors for the regulators should be ~100nF "high-K ceramic capacitors" + 47uF~100uF "electrolytic capacitors".
- For opamps, 100nF high-K ceramic should be fine, but you should consult with datasheets.
- Usually, you don't need to use tantalum capacitors for this purpose unless specified.
- Don't use film capacitors for power decoupling.

79XXs are less stable compared to 78XXs, and tend to become unstable depending on the load capacitance.
One should consult with the datasheet of each chip in order to know the proper capacitors values.
But also, you may need to tweak the capacitor value when necessary. Above recipe works most of the case.

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