I've thought of this for a while and it has come up I need to know how it applies to a usage:
In the PBP Manual, there is a simple blinking of an L.E.D. test in one of the commands as an example.
The circuit shows an output pin on a PIC to the L.E.D. anode and the cathode though a resistor to ground. PIC is running at 5 volts.
My question is how (since most L.E.D.s forward voltage is rated at 1.5 to maybe 3 volts) is the L.E.D. handling the output of the PIC without being destroyed.

I'm pulsing the IR L.E.D. in a Solid State relay (see link) and would love to avoid translating through a mosfet down to the nominal forward voltage of the L.E.D. shown in the data sheet. Pulses are from 1 to 40 milliseconds long. All of supply is a regulated 5 volts. Can I skip the translation voltage?

I've also seen 'power on' indicators go from Vin to resistor/L.E.D.

I don't get it.

https://media.digikey.com/pdf/Data%2...zzzERzz_DS.pdf