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ADF4351 internal and external voltages.

Posted: Mon Feb 12, 2018 2:05 pm
by i2NDT
hi all,
I just received my ADF4351 (see pic.) and I am a little puzzled...
in fact I noticed that on board there is a AMS1117-5.0 which is a 5 volts stabilizer...
as far as I know the ADF4351 needs 3.3 volt...maximum 3.6!
more over close to the DC input socket it's written: "DC 5V": but with 5 volts the AMS1117-5.0 cannot work as it needs at least 6.5 volts...
now I am wondering if they didn't put the wrong stabilizer on the board!!!
182621815915_1.jpg
182621815915_1.jpg (16.68 KiB) Viewed 3288 times
if someone has got the same board can check and verify what stabilizer is on board?

thanks a lot in advance!!!

i2NDT Claudio

Re: ADF4351 internal and external voltages.

Posted: Mon Feb 12, 2018 2:35 pm
by g8gtz
Hi Claudio

I have checked 2 units and they both have 1117-3 on them!

Well spotted - I think I would power with external 3volts!

73 Noel - G8GTZ

Re: ADF4351 internal and external voltages.

Posted: Mon Feb 12, 2018 6:18 pm
by g0mjw
Checking my boards.

One has no regulator - it is a different design, much smaller.
One has two regulators - it has a USB interface.
One has a 3.3V regulator.

Mike

Re: ADF4351 internal and external voltages.

Posted: Fri Mar 02, 2018 12:06 pm
by i2NDT
just to close the post:
I replaced the existing voltage regulator with an AMS1117-3.3 volt and now the board works perfecly well!!!

Re: ADF4351 internal and external voltages.

Posted: Fri Mar 02, 2018 12:31 pm
by g0mjw
Makes you wonder doesn't it. This arrived in the post. 5V regulator.

Re: ADF4351 internal and external voltages.

Posted: Fri Mar 02, 2018 12:55 pm
by i2NDT
gasp!
when I checked the ADF4351 datasheet I remember I saw "Power supply: 3.0 V to 3.6 V".
unless it is a new ADF...but I don't think so!
probably they loaded the machine with the wrong reel of AMS1107...and, when they realized that all boards were unusable, sold them as junk!
someone bougth the junk and resold as good...

Claudio

Re: ADF4351 internal and external voltages.

Posted: Fri Mar 02, 2018 4:45 pm
by G8GKQ
Thanks for the warning. I've also just had 2 new ADF4351 modules delivered with 5 volt regulators on!

Dave, G8GKQ

Re: ADF4351 internal and external voltages.

Posted: Sat Mar 03, 2018 8:49 am
by g0mjw
Unfortunately I have not got any AMS1117-3.3s or an order in progress to add one to, so have ordered some on Ebay. At 99p for 20, shipped from China, they seem far too cheap to be any good but we will see.

Re: ADF4351 internal and external voltages.

Posted: Sat Mar 03, 2018 9:49 am
by i2NDT
mmmmm...look at this offer...

https://www.ebay.it/itm/50PCS-AMS1117-3 ... SwaTFamf1I

50 for 1€!!!!!!!!!!

Re: ADF4351 internal and external voltages.

Posted: Sat Mar 03, 2018 12:21 pm
by G4FRE
Be careful. The last AMS1117-3.3s i bought from china with such a great deal gave 6.2v off load, 5,4V at 5 ma 4,4V at 15mA when 3 samples were tested. I binned them all in the end!

Buying voltage regulators from a "relaible source" is no guarantee either ..... https://g4fre.blogspot.co.uk/2016/11/if ... rnell.html

Dave
G4fre