App note: Output capacitive load considerations

Posted on Sunday, April 5th, 2015 in app notes by DP


App note(PDF) from Murata on output capacitors loading when in a switch mode power supply

There are numerous factors to consider when adding external capacitors to switched-mode power supplies (SMPS). This article will discuss noise, startup, ESR, stability, pre-bias applications, Sense inputs, On/Off (remote enable) controls and other topics.

Many real-world DC/DC applications require external bypass “bulk” capacitors as part of the output load. These capacitors supply extra current during a step load change. Lower DC voltages used in newer logic devices mean that the voltage margin difference between logic ZERO and logic ONE is reduced to hundreds or even tens of millivolts. Thus, since even modest power supply noise can cause data errors by exceeding this threshold, these bypass caps are necessary to reduce this DC/DC noise.

This entry was posted on Sunday, April 5th, 2015 at 5:00 pm and is filed under app notes. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.

One Response to “App note: Output capacitive load considerations”

  1. Luke Gary says:

    I have to put a serious thank you to the dangerousprototypes crew for continuously posting these great application notes from various companies. They are always a huge help to read and have done nothing but deepen my appreciation for designing quality hardware. Keep ‘Em Coming!!!

Leave a Reply

Notify me of followup comments via e-mail. You can also subscribe without commenting.

Recent Comments

  • Joe Desbonnet: Ya, I can recommend the low melting point solder. I used brand 'ChipQuik' and it's amazingly easy to use.
  • Jerome: I need a new BusPirate for the Fablab ;) Many thanks!
  • Max: Seems like an unexpectedly violent way to remove the chip indeed. A hot air station should of course do the job just fine, but in...
  • jose: Part removal described here is pure butchery, the cheapest hot air station will do a fast and clean job removing the QFP, heat air to...
  • Cody: Yes please