# Anyone have an idea to convert 0.6V - 1.3V to 0-5V with high sensitivity

Discussion in 'The Projects Forum' started by nlmardhiah, Jun 2, 2016.

1. ### nlmardhiah Thread Starter New Member

Mar 17, 2016
4
0
Hye Experts,

Anyone can help me on this problem...
I want to amplify my milivolt signal from 640mV to 1300mV to 0-5V with high sensitivity.
Currently i already tried to amplify but I can't get the output nearest or close to the range 0-5V..
what i get is from 2.8V to 4.8V..Anyone can give me an idea how to amplify my input n get the min output close 0.9 or 1V & max ouput close to 5 such 4.7, 4.8 or 4.9...Pls ..really need your idea so that I can study further on that & achieved my objective...huhuhu

2. ### ericgibbs AAC Fanatic!

Jan 29, 2010
2,605
396
hi,
This is one option.
Note: even with a rail to rail OPA, at 5Vsupply the maximum Vout will always be just under 5v.
Try a 6V supply.
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3. ### nlmardhiah Thread Starter New Member

Mar 17, 2016
4
0
Hye Sir,

Really appreciate your help...Its looks work....thankk you soo much for ur help...
But, may I know what type of op-amp did you use for U1, U2 and U3.. or can u suggest any model of op-amp to me?

4. ### AlbertHall Well-Known Member

Jun 4, 2014
2,290
451
You could use an open collector output op-amp, for instance LM393, where the output voltage can reach the supply voltage.

5. ### DickCappels Moderator

Aug 21, 2008
2,789
677
Can you post your existing circuit so we can see what is giving you the problem(s)?

Please include the power supply voltage(s).

6. ### ericgibbs AAC Fanatic!

Jan 29, 2010
2,605
396
hi,
The LM393 is an open collector output comparator.

@nlmardhiah
Use a MCP6002 dual OPA.
If you use a MCP6002, note the max Vsupply is +5.5v
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7. ### nlmardhiah Thread Starter New Member

Mar 17, 2016
4
0
Hi Sir,

Thanks for the idea.
I already try to built the cct on breadboard with op-am (U1 & U2) MCP6002. But some error occured.
So, can I confirm back the value that use for the each component =)

From the figure that you give :
C1 : 1u
R5 : 820
U3 : 10kpotzero
R4 : 2k
R3 : 14k
R7 : 2k
R6 : 4k
C2 : 100n
C3 : 47u

Tq.

8. ### ericgibbs AAC Fanatic!

Jan 29, 2010
2,605
396
hi,
Those values are almost correct and the circuit should work OK, note that R3 is a 20k pot to set the Gain.
Note, the 'k' between the value numbers is used as a decimal point ie: 2k2 =2.2k

What is the error.??

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