ADF4351 internal and external voltages.

Discussion about this major DATV Project. See also https://wiki.batc.tv/The_Portsdown_Transmitter
i2NDT
Posts: 40
Joined: Thu Nov 12, 2015 9:26 pm

ADF4351 internal and external voltages.

Post by i2NDT » Mon Feb 12, 2018 2:05 pm

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 1614 times
if someone has got the same board can check and verify what stabilizer is on board?

thanks a lot in advance!!!

i2NDT Claudio
i2NDT Claudio
Dalmine, Italia

g8gtz
Posts: 941
Joined: Wed Apr 07, 2010 6:26 pm

Re: ADF4351 internal and external voltages.

Post by g8gtz » Mon Feb 12, 2018 2:35 pm

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

g0mjw
Posts: 523
Joined: Sat Sep 20, 2014 9:15 am

Re: ADF4351 internal and external voltages.

Post by g0mjw » Mon Feb 12, 2018 6:18 pm

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

i2NDT
Posts: 40
Joined: Thu Nov 12, 2015 9:26 pm

Re: ADF4351 internal and external voltages.

Post by i2NDT » Fri Mar 02, 2018 12:06 pm

just to close the post:
I replaced the existing voltage regulator with an AMS1117-3.3 volt and now the board works perfecly well!!!
i2NDT Claudio
Dalmine, Italia

g0mjw
Posts: 523
Joined: Sat Sep 20, 2014 9:15 am

Re: ADF4351 internal and external voltages.

Post by g0mjw » Fri Mar 02, 2018 12:31 pm

Makes you wonder doesn't it. This arrived in the post. 5V regulator.
Attachments
ADF435X.jpg
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i2NDT
Posts: 40
Joined: Thu Nov 12, 2015 9:26 pm

Re: ADF4351 internal and external voltages.

Post by i2NDT » Fri Mar 02, 2018 12:55 pm

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
i2NDT Claudio
Dalmine, Italia

G8GKQ
Site Admin
Posts: 879
Joined: Sun Mar 22, 2009 1:21 pm

Re: ADF4351 internal and external voltages.

Post by G8GKQ » Fri Mar 02, 2018 4:45 pm

Thanks for the warning. I've also just had 2 new ADF4351 modules delivered with 5 volt regulators on!

Dave, G8GKQ

g0mjw
Posts: 523
Joined: Sat Sep 20, 2014 9:15 am

Re: ADF4351 internal and external voltages.

Post by g0mjw » Sat Mar 03, 2018 8:49 am

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.

i2NDT
Posts: 40
Joined: Thu Nov 12, 2015 9:26 pm

Re: ADF4351 internal and external voltages.

Post by i2NDT » Sat Mar 03, 2018 9:49 am

mmmmm...look at this offer...

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

50 for 1€!!!!!!!!!!
i2NDT Claudio
Dalmine, Italia

G4FRE
Posts: 45
Joined: Fri May 26, 2017 6:57 am

Re: ADF4351 internal and external voltages.

Post by G4FRE » Sat Mar 03, 2018 12:21 pm

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

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