kendon said:
[quote author=lasersbee link=1232324485/20#20 date=1232419624]By not using the 10 Ohm limiting resistor... you risk damaging the Potentiometer (pot)
near it's highest current output (lowest resistance).
Jerry
risk damaging the pot or damaging the ld? i am not aware of a way to damage the resistor by setting its resistance to the lowest value?
@rancor: interesting design
[/quote]
The lowest value of the pot would be the lowest resistance.... Since the circuit that we are talking
about has all the current supplied by the driver... go through that Current Limiting POT (without the
10 Ohm resistor) you can easily burn the resistive coating on the pot's resistive wiping area..
These standard pots are not rated for high currents (only fractions of a Watt) ... and the LM317
Regulator is rated and can supply up to 1 Amperes of current... Much more than required to burn out
your pot's resistive surface.
Remember.... with that LM317 current limited circuit... the lower the pot (resistance) value...
the Higher the output current of the LM317... and vise-versa...
From reading the posts on this thread... I would have bet money that you would have known this....
I seem to remember reading something like this on one of your posts referring to another member
that asked a valid question..
if you are not familiar with that you should seriously consider
a) visit physics class more often (if you are still in school)
b) get a book about this stuff
Or even read the Data Sheet...
I may be wrong.... :
Jerry