Help designing a low signal amplifier

[GeoMX]

Hi, I've been requested (in a course, I feel we're not being taught but lerning by ourselves) to design a circuit to amplify a 1 mVpp (f=1KHz) signal to 10Vpp, the idea is to show "how to" handle very low signals (e.g. microvolts coming from a probe), the problem is that I've not worked with circuits for a long time (I've been working in an instrumentation department for some years) and I need to remember what I knew (or what I've forgotten) as fast as possible .

I'm thinking of using two inverting amplifiers with a gain of -100 each, and using a pass-band active filter in between (well, I'm pretty sure I have to use opamps since that's what we've been talking about in the course), it's just that I "feel" it's too simple, I think it should be harder .

I don't remember anything about filter designing, but I'm sure I can remember after reading some information about it.

Could you please send me your comments/advice/suggestiongs/ideas for the circuit I've been requested (I'm not asking for a ready-to-use design, but if you have one I wouldn't complain )?

Thanks in advance for your help,
José Jorge.

PS. Sorry for my poor English (it's not my mother language).

 

[Optikon]

Hi, I've been requested (in a course, I feel we're not being taught but lerning by ourselves) to design a circuit to amplify a 1 mVpp (f=1KHz) signal to 10Vpp, the idea is to show "how to" handle very low signals (e.g. microvolts coming from a probe), the problem is that I've not worked with circuits for a long time (I've been working in an instrumentation department for some years) and I need to remember what I knew (or what I've forgotten) as fast as possible .

I'm thinking of using two inverting amplifiers with a gain of -100 each, and using a pass-band active filter in between (well, I'm pretty sure I have to use opamps since that's what we've been talking about in the course), it's just that I "feel" it's too simple, I think it should be harder .

I don't remember anything about filter designing, but I'm sure I can remember after reading some information about it.

Could you please send me your comments/advice/suggestiongs/ideas for the circuit I've been requested (I'm not asking for a ready-to-use design, but if you have one I wouldn't complain )?

Thanks in advance for your help,
José Jorge.

PS. Sorry for my poor English (it's not my mother language).

Hnadling microvolts coming from a probe is going to require much more than what you have suggested. Your suspicions are correct - it won't be that easy.

If you still want some suggestions about how to recover microvolts from noise & thermals - PM me, you may never return to read this so I wont waste my time.

 

[GeoMX]

Optikon: thanks for all of your help, I've got the circuit working. I used the AD620 instrumentation amplifier (one I could find here). The only problem was the frequency, I thought it was 1 KHz and it was 10 KHz!

Now we'll be working on a pH indicator circuit, I feel we can make it, but have little time, so I'd better go back to work !

Thanks again for your help,
JJ (GeoMX).