LNA questions  - Page 1
Forum section: electronics / beginners

author: hem213
author_rank: Contributor
timestamp: August 07, 2024, 09:16:57 pm
content: Hello everybody, this might be an unanswerable question considering the available information, but I would still love any advance.I'm considering two options for a low noise amplifier in my project, they seem somewhat unorthodox but I'm constrained financially so these are my only options for right now.the first one is a Chinese set up I found on Amazon that not only has the amplifier but also has the resistors, capacitors, SMA connectors, etc built in. This makes my life a lot easier as I don't have to be figuring out specific component values and whatnot. all i have to do is just connect my signal in/out. However, there is literally no datasheet, IC manufacturing codes, or any information whatsoever. All I can do is trust that it works.https://www.amazon.com/gp/product/B0D47PDRWV/ref=ox_sc_saved_image_5?smid=A2R5IUFZTHSEU3&psc=1the second one is an IC I found on Digikey, it manufactured by mini circuits which I know is a trusted source, it has all the included information that I could ask for. but of course, this is just an IC so there is a chance for failure that is much higher than the other choice because I have to build the rest of the circuit. I just really don't want to tinker around with a bunch of resistors and capacitors trying to make this work. If I must then I will do that, but it's not really something I want to do.https://www.digikey.com/en/products/detail/mini-circuits/PMA2-162LNA/19186503my question, what should I do? Should I just go with the convenience of the first one or go with the trusted second one, what would you do if you were in my situation? Or maybe there is a method where I can extract some more information off the Amazon one that I didn't see initially? Again apologies for this post as these are probably just all dumb questions. thank you in advance everyone!

author: MathWizard
author_rank: Super Contributor
timestamp: August 08, 2024, 02:22:30 am
content: What's the project ? Is this more like a test probe for another circuit, and that's why they have SMA connectors, and for low noise, and you hook it up to a scope or spectrum analyzer/etc ?I didn't see any reviews on that amazon link, it's possible it could do what they say, but yeah who knows, probably not.I bought some NOS of some ~2GHz op-amps from ebay, but yeah I probably can't even test them past a few hundred MHz. But it's nice to have something cheap that might be ok for hobby stuff.

author: ftg
author_rank: Frequent Contributor
timestamp: August 08, 2024, 10:28:59 am
content: The MMIC used on those Amazon amplifier PCB's could be some low cost one from NXP, they seem to like those small 6 pin cases.You could also search aliexpress with the image from Amazon and see if any of the sellers there mentions the MMIC used, or has good images showing the part code on the chip.Your final application does determine if the part you select is usable.If you want to save money and can wait a bit longer, you can likely get a selection of boards for evaluation from aliexpress for that 21usd you'd pay for five on Amazon.

author: liszt955
author_rank: Newbie
timestamp: September 13, 2024, 03:01:46 pm
content: The chip of that Amazon product is NXP's BGA2817,115 / TSSOP-6.You can refer to the chip's datasheet to make one yourself.