> > LED flicker can be noticeable well above 250Hz in some conditions
>=20
> I've got LED displays refreshed at 300Hz and that they aren't
> static is obvious if you move your head or roll your eyes. Refresh
> at higher frequency would still be noticeable as LEDs have no
> persistence

Likewise I've done 4 digit x 7 seg LED muxed displays at about 3 kHz (3kHz/=
4 digits=20
=3D 750Hz) and the effect is still there.

I've wondered about white LED's which I think use a phosphor (could be wron=
g=20
there) ~ does anyone know if that adds any measureable/useful amount of=20
persistence? So far I haven't seen any spec on this in datasheets.

--=20
Brent Brown, Electronic Design Solutions
16 English Street, St Andrews,
Hamilton 3200, New Zealand
Ph: +64 7 849 0069
Fax: +64 7 849 0071
Cell: +64 27 433 4069
eMail:  brent.brown@clear.net.nz


--=20
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