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general newbie vfd question
Posted: Thu Oct 24, 2002 12:18 pm
by Zombie
what is the response time for a VFD?
how long does a cell take to light up and then shut off.
I was looking at an LCD primarialy to use it as a spectrum analyzer out of winamp, but it seems the responce time of the LCD fluid is pretty long (about 100ms from what I've heard)
Posted: Thu Oct 24, 2002 9:29 pm
by linear
I should probably clam up and let the MO engineers answer, but here's how this works as I understand it (Henry can sort me out if I'm mistaken):
In the LCD world, that time is a function of temperature, and in a VFD it largely isn't. So if your application is say a car peecee, you will see some slower response out of the LCD at lower temps. A VFD would be largely immune to that effect (see how I hedge my statements...). I seem to recall rise and fall times being different as well, with fall times being ~2x rise.
If you ar working in a room temperature environment, I think the response time on the LCDs is quite adequate for winamp vis. 100 ms is in the ballpark for room temperature definitely, I know that LCDC can refresh at up to 25 frames per second, or 40 ms. I run it at 20 fps, and I'm watching it now and seeing only the slightest of damping as the peaks fall, and it actually contributes to the effect somewhat. I've cranked the frame rate down to 10 fps before, and it still looks pretty convincing.
Posted: Tue Oct 29, 2002 10:05 am
by Aniso
Yeah, exactly. What he said.
Plus, a bit of "I don't know". Henry has data he could look up in a file, but he asked me to post anyway, so...
"I don't know how fast VFDs are, off the top of my head"
Henry?
Posted: Wed Oct 30, 2002 1:30 am
by Cheese
Aniso wrote:Yeah, exactly. What he said.
Plus, a bit of "I don't know". Henry has data he could look up in a file, but he asked me to post anyway, so...
"I don't know how fast VFDs are, off the top of my head"
Henry?
They're pretty damn quick, I've got one here I run at 30fps and I've never noticed any blur...
Rob.