RF Amplifiers

[Goature]

Hello! 

I've been working on this RF project lately, and some questions have poped up along the way. I'm working on a transmitter based on the CC1050 chip from TI (http://www.ti.com/general/docs/lit/getliterature.tsp?literatureNumber=swrs044), but i want more juice (Yes, I've got a HAM license, callsign LB3TG  )! So I figured i needed to add an RF amplifier on the RF output.

My problem is basically that I don't know anything about RF amplifiers. I've configured the CC1050 to transmitt at about 433MHz on 10dBm (10mW). I want to boost the RF output to atleast 100mW.

I've tried to browse the RF amplifiers on Digikey, but I dont know that I'm looking for Can you give me some examples on RF amplifiers that will work for this application, please? I'm quite blank!

[w2aew]

You may want to browse the amplifier selections at http://www.minicircuits.com.  They've got many amplifiers that will meet your frequency requirements and +20dBm output level.

[XFDDesign]

Since you seem to be after a canned solution, instead of a home-rolled one, you're looking for MMICs (Monolithic Microwave Integrated Circuits). From the datasheet, you'll still need to use their matching network (page 9) before you drive anything else. An amplifier like the Analog Devices' ADL5536 might do the job, but its P1dB compression level is right at your output want. You would also need an attenuator to knock your output power down before gaining it up. Overall, this might be the most easy option if you don't mind the distortion introduced from the compression.

Personally if linearity is important, I might use an off-the-shelf power splitter, use two of the amplifiers, then another splitter as a combiner. (Something like the minicircuits SBTCJ-1W+ http://www.minicircuits.com/pdfs/SBTCJ-1W+.pdf). This route offers a few benefits for the cost: A 6dB attenuator feeding a 3dB splitter means 3dB of my power is actually doing something useful. When I gain up the two signals, they each stay below their compression point so they're more linear. Combine them again to get the 3dB summation boost. 20dBm with good linearity, at the expense of cost and power (the ADL5535s burn a lot of it).

[theatrus]

The CC1050 has a programmable output power and should be able to meet the input spec of an amplifier. Also, you will likely require an RF switch to bypass the PA in RX mode or to add an LNA in that path.