[time-nuts] Distribution amps and slew rate
dhooke at gmail.com
Sat Nov 3 17:44:09 EDT 2012
Given that slew rate is so critical, why do we distribute sine waves and
perform the zero-crossing detection at every target instrument?
> Trigger jitter is the noise at the trigger point. it's a combination
> of thermal noise and the slew-rate at the trigger points. It is often
> that trigger jitter is dominated by slew-rate, but there is also
> internal sources of trigger jitter. The slope dependent trigger jitter
> follows the formula:
> t_jitter = v_noise / s_slew
> t_jitter is the trigger jitter (s)
> v_noise is the noise power (V)
> s_slew is the slew rate (V/s)
> When the time-span of a measurement is long, long-term stability comes
> in as well as systematic drifts. Also, systematic noise such as hum
> also becomes important.
> To see how much you depend on slew-rate limitation, you can reduce the
> amplitude, and as this reduces the slew-rate you can separate the
> slew-rate dependent jitter from the intrinsic jitter of the input. It
> also helps you to identify if you need to work on the slew-rate limit
> rather than anything else.
More information about the time-nuts