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MCU's, LNA's and low level RF on a perfboard

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Sceadwian

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I've been lightly toying with micro controllers for the last year or so as well as absorbing as much electronics knowledge as I can outside academia. The chips I'm currently using can generate square waves at 12mhz (50% duty cycle) and the newer one's I'm looking at using can go as high as 32mhz. At these frequencies a simple two pole RC filter works pretty well at filtering out the harmonics but after two poles the voltage I'm left with is only 775mv's I can probably get this up to a volt or so by tweaking my R/C values but I'd like to end up with a signal voltage of at least 3 volts at a 50ma load (or as much more as is practical) Are there DIP packaged OPAMP's that work at these frequencie's / current /gain etc? I'm still a little floored at the sheer amount of chips that are out there I'd appreaciate any pointers people could give me, especially about building such circuits on perfboard (hand soldered) for simple low level RF frequency generation.
Just to give a little more information. The I/O can source 40ma at 4 volts square. Would a low noise RF opamp fed directly from the I/O and the R/C afterwards be better? If the opamp could source enough current the voltage drop from the R/C filters will go down, which might be better than trying to amplify a weak signal.
 

echo47

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    Sceadwian

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Sceadwian

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Actually 3v at 50ma was RMS, Not so much a sinewave as a low harmonic clock. That really needs to be close to a sine wave though so the distintiction is moot. I just don't need a 'pure sine' And when I say perf board I mean through hole style perfboard, which is basically PCB material with no plateing and .100" centered holes. All the connections will be done with enameld/insulated jumper wire. This is for hobby and for fun and learning so I have no intention of getting into the designing of a PCB or trying to make it look pretty. If I need a ground plane I can do that after sealing the board by using tin foil on one side connected to ground (yes it's tacky but it'd work) The parametric search for Analog's parts helps a lot thank you. Any more tips tricks or pointers would be appreciated from all users.
 

echo47

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I've used non-plated perf board too, with "1245 EMI Embossed Copper Foil Shielding Tape" (made by 3M) for ground areas. The Vector board was easier but more expensive. I chopped up the large board into many small projects.
 

    Sceadwian

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