Hoping someone can help me to understand what I am seeing.
I have the following:
A 5V DC power supply derived from a USB power supply
A LED (LINK) with a Forward Voltage requirement of 3.2V (Maximum Forward Voltage of 3.5V DC), and Continuous Forward Current of 20mA (Peak Forward Current of 100mA).
A 91 ohm 1/2 watt flameproof resistor
I used the popular LED Calculator to design this ultra simple circuit.
However, before connecting the LED I figured I'd use my multimeter to confirm that the resistor was properly dropping the voltage to 3.2V.
I tested this by placing the resistor first at the +5V side, and then at the GND side, of the appropriate multimeter leads -- but I am still seeing 5V on the meter.
I then place two of the same resistors in series, at both polarities, and I am still seeing the 5V on the meter.
Is there a simple reason I am still seeing 5V? Even without a load, I would have expected to see a voltage in the realm of 3.2V.
Thanks in advance.