Re: Choosing voltage opamp

Article View: sci.electronics.design

Article #2049

Back to sci.electronics.design Previous Next

#2049

From: Kevin White
Date: Fri, 29 Sep 2006 15:49

23 lines
2368 bytes

Vitaliy wrote:
...
>
> Johnny Boy wrote:
> >
> > You should listen to David, he knows what he's saying - even the very best
> > of rail-to-rail op-amps won't go close to the supply rails, except if
> > they're very lightly loaded, 1M etc. They still usually fall short of the
> > negative rail by 5-50mV and 0.5-1.5V short of the positive rail.
> > ... Johnny
>
> OK, I doublechecked the requirements, I don't have to get the exact
> 10Vp-p. Maybe I was getting such high output voltages (for OPA657)
> because of 1M load
...

You keep mentioning 10V p-p, but if you have a conventional
transimpedance amplifier you will get a unipolar signal so you will
only get a maximum of 5vp-p (0v to +5V) unless you offset the output or
AC couple the output amplifier.

kevin

Technical Details

Message-ID: <1159544975.956446.318660@c28g2000cwb.googlegroups.com>

Path: arc1-ca.pugleaf.net!g2news2.google.com!postnews.google.com!c28g2000cwb.googlegroups.com!not-for-mail

References:

<1159031128.442881.267560@m7g2000cwm.googlegroups.com> <1159037241.672300.204950@d34g2000cwd.googlegroups.com> <1159054293.852757.184420@e3g2000cwe.googlegroups.com> <7iSRg.15$KW5.10@newsfe02.lga> <1159475762.984027.308740@m73g2000cwd.googlegroups.com>

Show Full Headers

Complete Article Headers

X-Google-Thread: 112d1e,c037ff6b3e0ae32c
X-Google-Thread: 111d0a,c037ff6b3e0ae32c
X-Google-Thread: 103407,c037ff6b3e0ae32c
X-Google-Attributes: gid112d1e,gid111d0a,gid103407,public
X-Google-Language: ENGLISH,ASCII-7-bit
Path: arc1-ca.pugleaf.net!g2news2.google.com!postnews.google.com!c28g2000cwb.googlegroups.com!not-for-mail
From: "Kevin White" <kevinjwhite@comcast.net>
Newsgroups: sci.electronics.design,sci.electronics.basics,aus.electronics
Subject: Re: Choosing voltage opamp
Date: 29 Sep 2006 08:49:36 -0700
Organization: http://groups.google.com
Lines: 24
Message-ID: <1159544975.956446.318660@c28g2000cwb.googlegroups.com>
References: <1159031128.442881.267560@m7g2000cwm.googlegroups.com>
   <1159037241.672300.204950@d34g2000cwd.googlegroups.com>
   <1159054293.852757.184420@e3g2000cwe.googlegroups.com>
   <7iSRg.15$KW5.10@newsfe02.lga>
   <1159475762.984027.308740@m73g2000cwd.googlegroups.com>
NNTP-Posting-Host: 71.116.64.123
Mime-Version: 1.0
Content-Type: text/plain; charset="iso-8859-1"
X-Trace: posting.google.com 1159544981 2373 127.0.0.1 (29 Sep 2006 15:49:41 GMT)
X-Complaints-To: groups-abuse@google.com
NNTP-Posting-Date: Fri, 29 Sep 2006 15:49:41 +0000 (UTC)
In-Reply-To: <1159475762.984027.308740@m73g2000cwd.googlegroups.com>
User-Agent: G2/1.0
X-HTTP-UserAgent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.7.12) Gecko/20050915 Firefox/1.0.7,gzip(gfe),gzip(gfe)
Complaints-To: groups-abuse@google.com
Injection-Info: c28g2000cwb.googlegroups.com; posting-host=71.116.64.123;
   posting-account=-pcoXw0AAAD8CJgF2uh3HLQUXX9jp4RM

Reply to Parent Message