I am new at analog circuit design, so I need some help. I bought some Instrumentation Amplifiers: AD8421, AD8428 and AD8429 and the Evaluation board EVAL-INAMP-82Rz for them.
I want to test which InAmp is suitable for my application. In order to measure them, i need to provide a differential signal on the input of my Evaluation Board. My differential Signal should have 8MHz bandwidth.
I have a ROHDE & Schwarz HF-Synthesizer HM8134-3 that can create a single ended signal from 1 Hz to 1.2 GHz with -127 dBm to +13 dBm. (I also have a HUBERT A1020-75-250 High Frequency Amplifier, i dont know if i need that) Now I want to convert the single-ended-signal into a differential signal.
Is it possible to do that with some of the following Amplifiers:
AD8138 or AD8042 or ADA4941-1 or AD8475 ??
It should look something like this. Is this OK?
Thank you for using ADI products in your designs.
As to your question, you can use the AD8138 if you only need a gain of 1 but if other gains are desired then ADA4941-1 can be used. The AD8475 is a funnel amp which means that this will attenuate or reduce your output signal rather than amplify it. The AD8042 is a dual amplifier so I would not recommend this because other components are needed to configure this as a differential amplifier.
To help you better on this, is it okay if you tell us your application?
As for the in amp, what test will you do? There are measurements that would not require a diff amp at the inputs of the in amp.