I have a circuit that uses an LED and a simple buzzer.
I've created a basic circuit (below) and used a speaker to represent the buzzer.
I know two things about the buzzer :
- Rated Voltage: 12V; Range of Voltage: 3-24V
- Rated Current: 15mA at 12VDC
I'm not sure if that means max current but I'll just assume it does.
I use Ohm's law to calculate 3V / .015 = 200 Ohms and I place a 200 Ohm resistor in the circuit and I'm lucky enough because the LED will illuminate with that current. But I have a couple of questions.
Voltage Drop of LED
But that is probably incorrect, because the voltage drop of the LED is approx 2V, right? I probably need to calculate 1V / 0.15 and use a 60 Ohm resistor (or something close).
Would the buzzer work since it requires min of 3V and the LED drops the voltage by 2V?
I thought that voltage is variable within a circuit, but current is the same throughout?
Can you help me understand the steps I would take to calculate the proper resistor for this circuit and if it is possible to power both the LED and buzzer from the 3V power source?