I was wondering if anyone could give me a little information on amplifiers.

What would be the best way to amplifying a small, 1v @ 1mA, very high frequency signal (3-5MHz) to a high power signal? The output signal would also need to be around 3-5MHz and something like 12v @ 1A.

My question is, what amplifier system would preform this task well, or the best? One option is using a class E amplifier with a square wave signal, or just purchasing a direct high power, high frequency OP AMP.

Unfortunately I don't think any of these "OP AMPS" exist, so I'm looking to build my own circuit. Preferably something simple, but anything that works will do.

Has anyone got any suggestions of which amplification system would work the best in this situation?

EDIT: After some advice, it looks as if the OPA564 chip would be the best fit for this task. What other components are necessary to operate the chip? Or can I just operate it straight out of the box? Basically I'd like some advice on how I can successfully operate the chip.

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    \$\begingroup\$ very high frequency is usually 30-300mhz. Anyways this smells a little bit like an xy problem, can you tell us more about why you need that much current on your signal? What is it for/driving? \$\endgroup\$ – PlasmaHH Apr 29 '15 at 13:40
  • \$\begingroup\$ 12V rms, peak or peak-peak? There are some power opamps that might work. This comes close,ti.com/lit/ds/symlink/opa564.pdf. Otherwise a class A output transistor is easy.. but wastes lots of power.. heat. At which point I think you are stuck making your own push pull output stage. \$\endgroup\$ – George Herold Apr 29 '15 at 15:07
  • \$\begingroup\$ @GeorgeHerold Thanks for your response. If I wanted to buy the OPA564, would I need anything else? For example an evaluation board, or some specific resistors? I'm on a tight deadline so I really need to have this signal working soon. \$\endgroup\$ – Boris Deletic Apr 30 '15 at 0:57
  • \$\begingroup\$ Until you answer the amplitude question, I'm not sure the opa564 will work for you. It's full power bandwidth (10Vp-p) is only 1.3 MHz. \$\endgroup\$ – George Herold Apr 30 '15 at 1:26
  • \$\begingroup\$ It needs to be around 10 watts, this means something like 15v peak to peak @ 1A? \$\endgroup\$ – Boris Deletic Apr 30 '15 at 1:50

5 MHz is not that much, and neither is 1A.

For example, LTC1206 can amplify at up to 60MHz. Its output current is "0.25A to 1.2A".

OPA564 is up to 1.5A, 17MHz amplifier. Its gain-bandwidth product is a bit low (17MHz), so you will also want to add a regular, low-current preamplifier to it.


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