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From: john larkin <jl@glen--canyon.com>
Newsgroups: sci.electronics.design
Subject: Re: 50 ohm termination
Date: Tue, 18 Mar 2025 16:02:45 -0700
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On Tue, 18 Mar 2025 18:29:42 -0400, Toaster <toaster@dne3.net> wrote:

>On Mon, 17 Mar 2025 19:17:13 -0700
>john larkin <jlArbor.com> wrote:
>
>> On Mon, 17 Mar 2025 19:50:17 -0400, Toaster <toaster@dne3.net> wrote:
>> 
>> >Thank you for the advice. In my case I have a 10Mhz signal with very
>> >sharp transitions (500ps, 5V) and wanted to make sure I did things
>> >properly.
>> 
>> Interesting. What's generating the 5v signal? Lots of AC and Tiny
>> Logic chips are that fast, but might strain to drive 50 ohms. We use
>> several tiny triple buffers in parallel sometimes.
>> 
>> Regular thick-film surface-mount resistors are fine as terminators at
>> 500 ps.
>> 
>> LVDS line receivers are great at the receive end.
>> 
>> 
>
>I used a THS3111CD. Split up my project into a timing and driver board,
>so i have some 50 ohm BNC cables between and wanted to be extra safe
>about reflections at these higher frequencies.

Is the signal some analog thing, or a 10 MHz clock? The THS is an
opamp, but they can make good cable drivers too, even for clocks.

Lately I'm enamored of BUF602, a unity-gain 1 GHz beast.