I have several Christmas lights with different AC adapters.
First case
In the label of one of them, I read:
Primary: 220-240 V ~ 50/60 Hz
Secondary: 31 V DC 3.6 W
In the label of the cable connecting this AC adapter to the LED array:
Lamp: 3.2 V
0.064 W
80 LED
I can not understand if this is referred to the single LEDs, but the total amount of LED seems to be 80
.
How are they connected, then?
In the case of a series connection, each of them would have a 0.3875 V
voltage drop, which maybe is too small for a LED. If they were parallel, 31 V
seems too much for each of them, and the total available current 3.6 W / 31 V = 0.1161
would be 0.00145
per LED. So, neither of these solutions seems correct.
Second case
In another LED string, I have a 4.5 V
battery power supply, with no labels and therefore no indication about the current and the number of LEDs. Do they have a parallel connection?