How does a cap on a regulator output improve transient response? Is this cap not more appropriately drawn next to the load where it is not being defeated by intervening trace inductance? Or does this output cap serve a different purpose than the typical bypass caps seen on a digital IC power supply pin?


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Edit: This has been flagged as a possible duplicate. While the answers may have some overlap, the titles of the three questions I asked are very specifically different questions. This should be evident upon reading the Titles.

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    \$\begingroup\$ Possible duplicate of What is the purpose of the 7805 input capacitor? \$\endgroup\$ – Passerby Feb 13 '16 at 22:51
  • \$\begingroup\$ Please modify your first question if you have additional information you would like us to consider. This second question js too similar to that one to open a new thread over. \$\endgroup\$ – Robherc KV5ROB Feb 13 '16 at 22:54
  • \$\begingroup\$ Possible duplicate of electronics.stackexchange.com/questions/217085/… \$\endgroup\$ – Robherc KV5ROB Feb 13 '16 at 22:57
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    \$\begingroup\$ OK, so the output cap has nothing to do with the 7805 per se (e.g. compensation), but is just your usual bypass capacitor that would normally be placed at the load. This raises the question of why it would be mentioned in the application circuit at all, since the application circuit of just about any IC will also call out bypass caps on its VCC pins. If one blindly follows both application circuits, and the regulator is placed at the load, you wind up with doubled up bypass caps right next to each other. \$\endgroup\$ – mhz Feb 14 '16 at 12:22
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    \$\begingroup\$ endolith, that is a very good question, the user from the first comment above marked it as a duplicate to a similar but different question. different to anyone with basic reading comprehension. sadly I'm starting to see this stackexchange as less a place for learning and teaching as much as a place for hand waving and propping up ones ego. \$\endgroup\$ – mhz Feb 18 '16 at 9:49

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