I want to build 3 point clip powered by usb using SFH485P, and wiimote. the LEDs are powered by usb hub
this is the circuit diagram
http://links574.free.fr/freetrack/setups/led3s_usb.gif
USB positive lead -- PTC -- RES -- LED1 -- LED2 -- LED3 -- USB negative lead
having everything in series means that the voltage will be divided among all the components ie each led will get less than 3V.
should I use them in parallel instead with three resistors each with 2V drop?
http://www.free-track.net/english/hardware/calcled/led3p.gif
I understand that the fuse have to come before the resistor, or branching in case of paralel circuit.
PTC fuse with a 0.2A, however is 0.2A is the holding current or the tripping current
it will be more helpful if I got one picked up from here
http://uk.farnell.com/ptc-resettable-fuse
as for the Carbon Film resistor value and type Axial, I have no idea about the various other variables available, I just need something simple from here
http://uk.farnell.com/fixed-value
as I understand
100 ohm- 20mA
68ohm - 30mA
50ohm - 40mA
33ohm - 60mA
also I want to build wii sensor bar, however can I use the same IR LED, for that job? if yes then I would I require 4 or 6. also can I power this from another usb slot, and will it work better if I use high brightness so I can get further away?
one last question, how long is the SFH485P when run at near 100ma, in case both the sensor bar and clip
does brighter LED means further distances from the wii mote?
also how long is the life time for the IRLED at different currents
please share your experience so I can order the right amount of IR LED once the old ones burn out
kindest regards
