Low ESR Capacitors?

[koossa]

Good day

I have asked for low ESR Electrolytic Capacitors, and they gave me the following 3 types :
http://www.hitano.com.tw/PDF/EXR.pdf
http://www.hitano.com.tw/PDF/E5R.pdf
http://www.hitano.com.tw/PDF/EHR.pdf

How do I know if they are low esr?

[timpati]

first of all, you must make an ESRmeter circuit and then measure them. its the best action, trust me.

[Ioannis]

the cheapest way to measure ESR is with a digital storage oscilloscope and a simple R network.

If you have this tool, tell me to look for the setup and post it.

Capacitors are very tricky in high (>40C) temperatures and if you have around heatsinks or other elemets that they are getting hot, please consider moving them away.

Maxim I recall had a nice tutorial oin this subject but cannot find it now. When..., I will...

Ioannis

[Charlie]

If ESR or ESL is critical, then perhaps electrolytics are not the way to go. What value do you need?

[Ioannis]

Here is the promissed link for the capacitors that can be the bad guy in your circuit.

http://pdfserv.maximintegrated.com/en/an/TUT5527.pdf

Ioannis

[Charlie]

Good day

I have asked for low ESR Electrolytic Capacitors, and they gave me the following 3 types :
http://www.hitano.com.tw/PDF/EXR.pdf
http://www.hitano.com.tw/PDF/E5R.pdf
http://www.hitano.com.tw/PDF/EHR.pdf

How do I know if they are low esr?
I think you will have to call the manufacturer and ask - the data sheets provided don't specify it. You will need to know your frequency of operation, voltages, and temperature since these impact it as well. Someone mentioned getting a sample and measuring it which is a good place to start, but you will need a spec if you want to use it in a commercial design. I'm not sure why the paper on ceramics was posted, but Electrolytics and not known for great ESR / ESL, so you may wish to look at a different technology like ceramic, metal film, or even tantulum depending on your application, in which case the paper is a good reference.

We can probably help more with better information about what you are doing and what your circuit looks like. As usual, the answer varies widely depending on the application.

[spcw1234]

I don't think he needs help anymore since the thread dates back to 2005 ;)

[Charlie]

LOL - I missed that Shawn - good spotting.