about LH0002 Buffer

Hello Sampath,

I am having a hard time finding the specifications for that buffer.  Can you list the key parameters you would like to match and what value you require? 

What is  your application, and do you have package requirements?  The metal can package is no longer supported to the best of my knowledge. 

Thanks,

Loren

Dear Friends

I finally found that BUF634 with 30 MHz bandwidth is good replacement for the LH0002 Buffer. But, now I encounter a different problem

We are currently working on log RF antenna (logarithmic amplification). Our output voltage swing between 2.0 to 0.6 and we need to swing output voltage in between -1.0 to 1.0 voltage and -3dBvoltage between 6 to 10 (max 10) with a gain of 1.2.

I highly appreciate if you can suggestion me op amps for above condition

(I prefer to use single ended differential op amp.)

Thank you

Your sincerely

Sampath

Hi Sampath,

Can you post a block diagram?  I am not completely understanding your requirements.

By 3db Voltage do you mean bandwidth.  Are you looking for 10MHz of 3dB bandwidth?

Regards,

Loren

Dear sir,

Thank you very much for your kind reply

I am attaché here with some figure.

My question is what kind of circuit is necessary for doing this and what is the best op amp for that.

Thank you

I just construct the following circuit for experiment. My problem is when I apply the 5 DC voltage to the noninverting input that also appear on inverting input that’s mean my signal input shift to the 5 DC level. Can you explain what is the reason behind that?T_02.pdf

Dear friend,

As you said I set the reference voltage (VCD1 to 1.198V) but I did not change amp gain to a gain of 1.25. because, I could not find the 1.25K at that moment. my problem is why I am having input voltage shift to the about reference voltage. Is that ok or something wrong

I am attaché here  with some of images of my oscilloscope.

yellow line is the  “input”

Thank you!

Dear Lorens,

I finally constrict the following circuit digamma. Our DAC card bandwidth about 20 MHz we do not want to introduce any filter. I highly appreciate if you can provide better alternative op amp instead of OPA602.

by the way, I am Waiting for the thunderstorm to test my circuit

Thank youT_03.pdf

Hi Sampath,

THe supply voltage will limit the number of suitable parts.  What about the OPA1612? The OPA1664 may also work. 

I am using our parametric search tool for precision amplifiers with bandwidth around 20MHz and 22V or higher supply voltage:

Regards,

Loren