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Hi Mr. Setsuda,

I am designing a power supply circuit which will use supercapacitors for backup.

I was wondering if supercapacitors have discharge current ratings? This pdf below (on bottom of page 3) seem to imply that there are limits on operating currents for supercaps, but there was nothing on the product page or data sheet itself regarding current.

Also, I am thinking of using a supercapacitor charger in the circuit. Is it safe to set up the charge voltage limit at exactly the maximum voltage rating of the supercap, or is it a bad idea? For example, setting maximum voltage limit to 2.5V on 2.5V supercaps. Will they blow / degrade quickly if they are cycled to maximum capacity regularly?

Thank you,

Irving

Hello Irving san

>I am designing a power supply circuit which will use supercapacitors for backup.

---->Super capacitors is My competitor 'N' bland.

      Please note Panasonic EDLC(Electronic double layer capacitor) bland name is 'Gold Capacitor'.

     But Thank you for your EDLC request to Element 14.

>I was wondering if supercapacitors have discharge current ratings? This pdf below (on bottom of page 3)

>seem to imply that there are limits on operating currents for supercaps,

>but there was nothing on the product page or data sheet itself regarding current.

--->I do not understand your PDF in above question, Could you attach your PDF again?

    and

    What discharge current value do you need?

> Also, I am thinking of using a supercapacitor charger in the circuit.

> Is it safe to set up the charge voltage limit at exactly the maximum voltage rating of the supercap,

> or is it a bad idea? For example, setting maximum voltage limit to 2.5V on 2.5V supercaps.

> Will they blow / degrade quickly if they are cycled to maximum capacity regularly?

--->Basically You can use 2.5V charging voltage for 2.5V EDLC Gold cap.

     But depend on your request life time and charging/Discharging profile,

     We must propose suitable EDLC.

     Please see attached file.

     Here is Gold cap requirement sheet.

     Could you please fill into this sheet and send back to me?

     Then I will reply someting proosal to you.

Thanks

Setsuda

Thank you,

This capacitor has a mil part number CMR04C180JPDP, can you cross referrence to newark electronics Part Number

Hello Hernand san

CMR04C180JPDP is CDE products, not Panasonic capacitor.

But I checked CDE Web for you.

This product is Mica cap.

Rough SPEC is

CMR Serie

Temp. Coeff.ppm/°C–200 to +200
CapacitanceDrift±(0.5% +0.1pF)
Standard Cap. Range1 – 18 pF
Caps 18pF

+/- 5% Cap tolerance

-55deg to 150deg

500V Dc

Failure rate 0.1%/1000hours

Unfortunately

There is exact same spec product as above in Farnell Mica Caps site.

But CDE is Cornell Dubilier.

There are many Cornell Dubilier Mica cap in Farnell Mica Caps site

So At first

Please access Farnell Mica caps web.

http://uk.farnell.com/mica

Then please use search engine in this web to find out your requested product.

Thanks

Setsuda

I've been looking for replacement capacitor to replaced buldging ones in monitor. On looking through the specs noticed that Panasonic electrolytic aluminium case ESR capacitor have life of 2000 hours with some going as high as 20,000hrs. I am actually very surprise with the low life.

What is the difference between them and under what condition would you use a 2000hrs capacitor in a product

I've been looking for replacement capacitor to replaced buldging ones in monitor. On looking through the specs noticed that Panasonic electrolytic aluminium case ESR capacitor have life of 2000 hours with some going as high as 20,000hrs. I am actually very surprise with the low life.

What is the difference between them and under what condition would you use a 2000hrs capacitor in a product

Hello Lim san

Thank you for your request.

But I do not understand your question clearly.

Please let me know our Lytic cap series name for 20,000 hours which you mentioned..

We Panasonic do not have 105deg 20,000 hours guarantee life time Lytic capacitor.

We have 105deg 10000 hours quarantee life time Lytic Capacitor.

Thanks

Setsuda