# clamper using opamp

Discussion in 'The Projects Forum' started by onlyvinod56, Mar 4, 2013.

1. ### onlyvinod56 Thread Starter Senior Member

Oct 14, 2008
362
1
Hello.

I have a symmetrical triangular wave with specifications mentioned below:

Vpp = 2v
freq = 1000Hz. (voltage swings from +1 to -1)

i need two clamper circuits such that the following requirements should be fulfilled.

1) Vpp = 2V; same freq.; voltage should swing from +2v to 0v

2) Vpp = 2V; same freq; voltage swing range +4v to +2v

I have few 741 opamps and i want to utilize them.

2. ### w2aew Active Member

Jan 3, 2012
219
64
Easy to do with the 741. Power it up with a dual power supply (+/-9, or 12 or 15V). Configure as inverting unity gain (output connected to inverting input via 1K resistor, and 1K resistor from inverting input to your signal. Then, arrange a voltage divider that will apply +1V to the non-inverting input. This will invert the triangle wave (won't matter it is symmetrical), and cause the output to vary between +2V and 0V.

Same circuit as above, but create a voltage divider to apply +1.5V to the non-inverting input. This will cause the output to vary between +4V and +2V.

onlyvinod56 likes this.
3. ### Ron H AAC Fanatic!

Apr 14, 2005
7,049
659
That will work, IF you make the voltage on the non-inverting input +0.5V.

If the inversion is not acceptable,there are various ways to do it.

BTW, these are not clampers, they are level shifters.

4. ### onlyvinod56 Thread Starter Senior Member

Oct 14, 2008
362
1
Thankyou w2aew.
Does this shifter work for any frequency?

5. ### onlyvinod56 Thread Starter Senior Member

Oct 14, 2008
362
1
Tell me if iam wrong.....

Inversion can be cancelled here by giving the signal to non inverting terminal.

Or

For the same circuit i have to connect a non inverting amp again.
OK. level shifters. Thankyou RON.

6. ### Ron H AAC Fanatic!

Apr 14, 2005
7,049
659
You can do it with a noninverting circuit, but of course it will be different than that described by w2aew. Or, you can use his circuit (with the change that I mentioned in post #3), but you will have to change the DC offset voltages from positive to negative, and add an inverting unity gain circuit.

7. ### onlyvinod56 Thread Starter Senior Member

Oct 14, 2008
362
1
Here are my simulated results.

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8. ### onlyvinod56 Thread Starter Senior Member

Oct 14, 2008
362
1
Ok. I'll simulate it. I'll be back soon.