Five-LED AC Nightlight
A while back I took apart a small three-LED nightlight bulb to see how it was put together.
I thought that the three-LED bulb was a bit dimmer than I wanted when the grand kids visited so I worked out a version that was brighter. I found that running the LEDs at their intended 3 Volts each was too bright. In playing with the circuit I went to five LEDs and lowered the voltage to where I liked the brightness level. This circuit also ended up with resistor and capacitor values more to my liking, meaning that I had them in enough quatities in the junk box to be able to make more than just one nightlight.
Below is the image of the small wall wart case used with the five-LEDs installed:
The parts I used are listed below and the schematic is below the parts list.
Next is a photo of the inside of the nightlight case. The circuit is put together in what is known as the "dead-bug" style. A dead bug is usually on its back with its legs in the air, just as the LEDs and the fullwave bridge are shown in the photo.
The holes in the case for the LEDs, were drilled to point the LEDs to the four corners and the one in the center was pointed out straight. I figured a little pointing would help illuminate all corners of the room.
The LEDs were sanded after they were installed into the case top and the case glued shut. The marks left by the sanding can be seen on the case in the photo below. The sanding helps disburse the light into a wider area.
The nightlight had its burn-in test when two of our granddaughters stayed with us the weekend after this nightlight was completed. It worked flawlessly, providing enough light in the bathroom for easy access. The last photo is of the nightlight plugged into a wall socket.
The GOOD news: When I measuered the AC current being used by this night light it was 1.2 μA, that's 0.0000012 Amps! This translates to around 120 V X 0.0000012 A = 144 μW, thats 0.000144 Watts!
NOTE:Your power usage may vary depending on the LEDs you use. I built a second one of these and used some flat-top ultrabright white LEDs which used more current and came in at around 300 μW. Still, that's ~ 0.0003 Watts!
(ke3fl - 10/06/2020)
Other LED projects include a replacement Car boot/trunk lighting, Ham Shack Lighting, LED Tester, and a Piano Light "bulb" out of two LED modules with three LEDs in each of them, the base of a dead LED light bulb, and the circuit from inside a 12V, 500mA switching power supply.
Here's a simple Joule Thief based LED Tester, and don't forget the Joule Thief test/experiments page that started all these LED replacement lighting projects.
The Traveler's Nightlight, Link: The Traveler's Nightlight
Phil Karras, KE3FL
Return to: previous page Return to: [My Home page]