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Feedback section if space allows.
Anyone know a rule of thumb for
determining how much energy you can
pump into an LED without destroying
it? I've seen many specs on maximum
voltage, current, and duty cycle.
However, I’m trying to determine how
much current you can actually pump
into one in a short duration pulse
(around one microsecond) without
damaging the LED junction, and at
what maximum repetition rate. I've
heard of strobe applications where 10X
the maximum absolute current could
be pulsed without destroying the LED.
But what is the limit and how do you
determine it from the specs?
#1081 Tom Campbell
Does anyone know of a circuit
that can produce pulses at a constant
(but adjustable) duty cycle (around 3%
or less) from 20 Hz to 20 kHz? I have
seen many designs that can vary duty
cycle or frequency, but not both
without one affecting the other. This is
for a strobe application.
#1082 Tom Campbell
I am working on a bingo flash
board that will be shipped to Honduras.
It is the big board that everyone
watches after the bingo numbers have
been called. It has 75 lighted 2" x 2"
segments that can be individually lit as
the numbers are called. I have the
bingo machine controller but it is old
and unfixable. What I need to do is
come up with a way to control the
lighted board. I am open to suggestions. I thought about using a PIC and
a digital input pad to input the number.
You could even use relays and 75
switches but having that many wires
may be a bit much.
#1083 Charlie Brown
How can I extract music files
(usually .wav or .mp3) embedded in
Microsoft Power Point files?
#1084 Steve Buu
Is there a way to export stock
market data from the Internet (PC)
through USB or RS-232, to be displayed
on a homemade stock sticker?
#1085 Steve Buu
Where is the current cursor
position from the mouse stored in
Windows (PC) and how can it be
accessed? I want to externally control
the cursor in addition to the mouse.
#1086 Steve Buu
Brushless motors are more
powerful and efficient than the old
brush motors but are much more
sensitive to overload/overcurrent. For
radio control and robot competition, I
Jaunary 2008 101