Cross-talk square-wave?

[Chuck Guzis]

On 03/30/2017 09:07 PM, Tony Duell via cctalk wrote:


> The fundamental rule is 'You can't change the voltage across a
> capacitor instantly'. There is a related one 'You can't change the
> current through an inductor instantly'. It (of course) doesn't matter
> if said capacitor or inductor is an actual component or 'strays'.

Funny that driving DRAMs would be mentioned today.   Yesterday, I was
going through some of my old tubes of ICs and ran across some AM2966
DIPs.  I didn't remember why I'd gotten them or even what they were.

A glance at a datasheet  refreshed my memory--basically they're LS244
octal drivers intended for MOS memory address lines.  They feature 25
ohm resistors in the collectors of both of the totem-pole output
transistors.  Each output is spec-ed to sink a minimum of 50 ma.

It takes some muscle to drive a capacitive load.

--Chuck