differential amplifier
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Hello;
I would appreciate any resources or circuit information anyone might have for
building a differential amplifier to transform a ~1.5 mV differential into
something
usable for reading through an ADC connected to my stamp (i.e. amplifying the
signal
from ~1.5mV to roughly 5V).
Thanks in advance,
Hans
I would appreciate any resources or circuit information anyone might have for
building a differential amplifier to transform a ~1.5 mV differential into
something
usable for reading through an ADC connected to my stamp (i.e. amplifying the
signal
from ~1.5mV to roughly 5V).
Thanks in advance,
Hans
Comments
--- hrs_mtl <hans@a...> wrote:
> Hello;
>
> I would appreciate any resources or circuit information anyone might
> have for
> building a differential amplifier to transform a ~1.5 mV differential
> into something
> usable for reading through an ADC connected to my stamp (i.e.
> amplifying the signal
> from ~1.5mV to roughly 5V).
>
> Thanks in advance,
>
> Hans
>
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject
> and Body of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>
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Most op-amp spec sheets have a typical operating circuit. I'm no good at
ascii art, so I won't try, but the circuit is very simple. If you search
around on the web you will find many sites with op-amp circuits and
information. A single rail type is probably best for your application, like
an LM324. Microchip makes some single rail op-amps, and I have been playing
with their programmable gain amps, for which you can set the gain with your
Stamp if you need different levels of amplification.
HTH,
Jonathan
www.madlabs.info << Home of the hydrogen powered robot!
Original Message
From: "hrs_mtl" <hans@a...>
To: <basicstamps@yahoogroups.com>
Sent: Thursday, March 18, 2004 8:56 PM
Subject: [noparse][[/noparse]basicstamps] differential amplifier
> Hello;
>
> I would appreciate any resources or circuit information anyone might have
for
> building a differential amplifier to transform a ~1.5 mV differential into
something
> usable for reading through an ADC connected to my stamp (i.e. amplifying
the signal
> from ~1.5mV to roughly 5V).
>
> Thanks in advance,
>
> Hans
>
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>
>
to about 3.5v (positive rail) with a 5 volt supply. Forget what the negative
rail limit is - though I seem to remember 0.5 volts or something.
When looking for an opamp - check for rail to rail single supply types. That
means that with 0 and 5v supplied to it, it can actually output 0-5v.
Another tip - with those kinda of gains, make SURE you use caps on all your
chip supplies. Also put a cap between the +5 and 0 volt supply of the opamp
itself. A tiny bit of noise that would normally not be noticable on a
non-amplified output will be humungous after its amplified 2500 times. If
you don't have access to an oscilloscope, this could be a tough one to get
stable.
>
Original Message
> From: Jonathan Peakall [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=6jAZJ65HUsV0dSuSYZtcY7J1JhAfpZIbuXEcDykaSTE-48XVCFUkf35nRjOxN_nLsF8j8x6DZkcJmznrKs4X]jpeakall@p...[/url
> Sent: March 19, 2004 7:30 AM
> To: basicstamps@yahoogroups.com
> Subject: Re: [noparse][[/noparse]basicstamps] differential amplifier
>
>
> Hans,
>
> Most op-amp spec sheets have a typical operating circuit. I'm no good at
> ascii art, so I won't try, but the circuit is very simple. If you search
> around on the web you will find many sites with op-amp circuits and
> information. A single rail type is probably best for your
> application, like
> an LM324. Microchip makes some single rail op-amps, and I have
> been playing
> with their programmable gain amps, for which you can set the gain
> with your
> Stamp if you need different levels of amplification.
>
> HTH,
>
> Jonathan
>
> www.madlabs.info << Home of the hydrogen powered robot!
>
>
>
Original Message
> From: "hrs_mtl" <hans@a...>
> To: <basicstamps@yahoogroups.com>
> Sent: Thursday, March 18, 2004 8:56 PM
> Subject: [noparse][[/noparse]basicstamps] differential amplifier
>
>
> > Hello;
> >
> > I would appreciate any resources or circuit information anyone
> might have
> for
> > building a differential amplifier to transform a ~1.5 mV
> differential into
> something
> > usable for reading through an ADC connected to my stamp (i.e. amplifying
> the signal
> > from ~1.5mV to roughly 5V).
> >
> > Thanks in advance,
> >
> > Hans
> >
> >
> >
> >
> > To UNSUBSCRIBE, just send mail to:
> > basicstamps-unsubscribe@yahoogroups.com
> > from the same email address that you subscribed. Text in the
> Subject and
> Body of the message will be ignored.
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the
> Subject and Body of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>
>