Re: Fast sampler

On 2025-03-05 19:15, john larkin wrote:

On Wed, 5 Mar 2025 18:20:47 -0500, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:
 

Hi, All,
>
Late last year we did a fast sampler/TDR with nice clean 60 ps edges.
>
We're gearing up to actually sell them, so I did a short technical
writeup on the design, which may be of interest.
>
<https://electrooptical.net/News/a-high-performance-time-domain-reflectometer>

 Neat. No step-recovery diodes.

Well, 40 years does get you something sometimes. ;)

 The LVDS line receivers are radical parts, for 30 cents.
 We also used ATLC2 to get a good match of a cheap fat-pin edge-launch
SMA connector to a multilayer PCB. That was fun.

Yeah, you tipped us off to the possibility, so Simon cranked on it. Deleting the L2 and L3 grounds, and via-stitching a L4 ground through the whole stack, makes the cheap connectors pretty good.
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510
http://electrooptical.net
http://hobbs-eo.com