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[DPRG] Electrolytic

Subject: [DPRG] Electrolytic
From: Shaun Parsons Shaunp at CASHPOWER.CO.ZA
Date: Wed Jan 14 23:46:00 CST 2004

0.1uF 0805 Ceramics should be fine.
Placing 2 caps in parallel will reduce the ESR of the cap and ensure that
you will have at least 
0.16uF. (2x 0.1uF -20% worst case), but is not necessary unless your RS232
lines will be heavily load. (long serial link, high baud rates etc.)


-----Original Message-----
>From: Ed Okerson [mailto:eokerson at texasconnect.net]
Sent: Wednesday, January 14, 2004 11:33 PM
To: DPRG List
Subject: [DPRG] Electrolytic

I am working on a 3.3V circuit and need to connect it to a serial RS232
port.  So I picked up some MAX3232 chips and started pondering.  The spec
sheet shows 5 capacitors connected to the chip, all of them 0.1uf and all
are marked with a + on one side.  That would seem to indicate to me that
they are using electrolytic capacitors.  My question is this:  Is it
really necessary to use electrolytics in this circuit?  I have scads of
0805 surface mount 0.1uf caps, and can make the board a lot smaller with
them.  I have no surface mount electrolytics, and all of the 0.1uf
electrolytics that I do have will use a lot more board space.  Any

Ed Okerson

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