High Temp Caps Vs. General Purpose Caps

[Ritalin]

Forgive me if this has been posted already, I tried to search for a topic like this, but nothing came up. Also, if this is the correct place to post something like this.

I'm looking to order some replacement caps for a few projects I've been working on, mainly fixing LCDs that have gone bad. For the most part I would replace a part such as a 1000uF-10V with a 1000uF-25V and it would work. So far I've fixed 6 monitors doing a simple switch out like that. Yet, the parts that I have been replacing were rated at 80*C.

But now I'm working on a project where everything is 105*C. I was told by one of my EE buddies that the whole "High Temp Vs. General Purpose" is more of a selling feature and I should just replace what ever is bulging with the same thing of a higher voltage, something around 35V to 50V.

Any thoughts? I am just a 'hobbist' so go gentle on the lingo

[Wizard]

Re: High Temp Caps Vs. General Purpose Caps

Tell your EE friend to listen to our sayings:

1. You need to redo your fixes on all the stuff fixed with proper 105C high ESR capacitors such as samxon RS or GT series.

2. Working voltage replace with like or few volts above and one issues you need to know about. Also some capacitors can be in same physical size with larger uF rating. Examples:
6.3V to 6.3V or 10V
10V to 10V or 16V
16V to 16V or 25V.

680uF to 820uF or 1000uF so on.

The issue is physical size is much larger on some capacitors as you go up on voltage or uF. These usually fits or will not fit for ANY reasons. I had 2 issues on one TV where diameter, height was crucial.

General caps is good on low ripple, low current ripple and signal coupling and in some cases where temp is not a problem. But general purpose caps have wrong reason to be on voltage rails/SMPS/high ripple and heat issues.

Cheers, Wizard

[kc8adu]

Re: High Temp Caps Vs. General Purpose Caps

you mean low esr?

Tell your EE friend to listen to our sayings:

1. You need to redo your fixes on all the stuff fixed with proper 105C high ESR capacitors such as samxon RS or GT series.

2. Working voltage replace with like or few volts above and one issues you need to know about. Also some capacitors can be in same physical size with larger uF rating. Examples:
6.3V to 6.3V or 10V
10V to 10V or 16V
16V to 16V or 25V.

680uF to 820uF or 1000uF so on.

The issue is physical size is much larger on some capacitors as you go up on voltage or uF. These usually fits or will not fit for ANY reasons. I had 2 issues on one TV where diameter, height was crucial.

General caps is good on low ripple, low current ripple and signal coupling and in some cases where temp is not a problem. But general purpose caps have wrong reason to be on voltage rails/SMPS/high ripple and heat issues.

Cheers, Wizard

[shovenose]

Re: High Temp Caps Vs. General Purpose Caps

Lol yeah i saw that too

[Ritalin]

Re: High Temp Caps Vs. General Purpose Caps

So ideally I want to replace it similar to what's installed, but one 'level' higher?

And does it matter if I install a high temp cap were a lower temp cap is install?

[Wizard]

Re: High Temp Caps Vs. General Purpose Caps

Good spotting. What a Blooper, I meant low ESR! Thanks.

We are talking about where the need for 105C is usually on mainboard for PC, power supply and where there's heat issues.

On other hand, the 85 C is usually on the cool running boards where signal circuits is used but not for power filtering/bypass caps.

Cheers, Wizard