DDS questions

"John Miles, KE5FX" <jmiles@gmail.com> wrote:

> On Saturday, August 13, 2022 at 11:04:08 PM UTC-7, Mike Monett wrote:
>> I'm interested. Can you name some of the best and who sells them? 
> 
> LMX2820 (TI) and 8V97003 (Renesas) are two of the best integrated
> PLL/VCO parts I've seen.  The LMX2595 has similar specs but the 
> LMX2820 has some nice advantages, such as lower flicker noise and 
> the ability to drive both phase detector inputs externally.
> 
> Look them up on octopart.com and you'll see that they are all 
> sitting in Chinese warehouses by the tens of thousands, waiting for 
> buyers who don't mind paying 4x-5x MSRP.  
> 
> ADF4371 (62.5 MHz - 32 GHz) also looks good.  Some stock left at
> Mouser.   
> 
> Of all these parts, I've only messed with the LMX2820 in person.
> I have a demo board for the Renesas part but haven't gotten
> around to powering it up and trying it out yet.
> 
> -- john, KE5FX

Very good info. Thanks



-- 
MRM

Gerhard Hoffmann <dk4xp@arcor.de> wrote:

[...]

 
> If someone wants to play with these things, there are enough
> boards. Hot air soldering is required, minimum.
> 
> cheers,
> Gerhard   DK4XP
 
Very interesting. Thanks

Mike VE3BTI 
 



-- 
MRM

On Sun, 14 Aug 2022 00:19:53 -0700 (PDT), "John Miles, KE5FX"
<jmiles@gmail.com> wrote:

>On Saturday, August 13, 2022 at 11:04:08 PM UTC-7, Mike Monett wrote:
>> I'm interested. Can you name some of the best and who sells them? 
>
>LMX2820 (TI) and 8V97003 (Renesas) are two of the best integrated
>PLL/VCO parts I've seen.  The LMX2595 has similar specs but the 
>LMX2820 has some nice advantages, such as lower flicker noise and 
>the ability to drive both phase detector inputs externally.
>
>Look them up on octopart.com and you'll see that they are all 
>sitting in Chinese warehouses by the tens of thousands, waiting for 
>buyers who don't mind paying 4x-5x MSRP.  
>
>ADF4371 (62.5 MHz - 32 GHz) also looks good.  Some stock left at
>Mouser.   
>
>Of all these parts, I've only messed with the LMX2820 in person.
>I have a demo board for the Renesas part but haven't gotten
>around to powering it up and trying it out yet.
>
>-- john, KE5FX

We use the LMX2571 as the internal trigger generator in one product.
Jitter is great. It was a huge pain to program, as TI doesn't reveal
the code that they use in the demo kit. Everybody has to figure it out
for themselves. The data sheet is 62 pages long and the app note is
another 31.

We have to suspend triggers while reprogramming the synth, which some
users don't like.