Remaking the Totoro lamp

Hi all! My mother and I really love the work of Hayao Miyazaki, and my mother also does not like to sleep without a night light. Having added simple 1+1, I decided to give her a night light with Totoro.

Here it is!

However, when researching how it works, I discovered that the light is powered by a battery. I really don’t like using battery-powered devices, because they always run out, you have to buy them, you go to buy them, you realize that you don’t remember the size, or it’s not in the store, when you find the one you need you’re shocked by the prices, buy them cheaper, they run out in two days. .. In general, I couldn’t afford to give myself a night light with such unuser-friendly functionality and decided to upgrade it.

The entire chronology of events in real time from idea to implementation and my mother’s reaction have already been seen by subscribers of my channel Everyday Life of an Electronic Worker on Telegram https://t.me/lokicheese. In addition to my projects and mini stories from my factory life, technical memes and all sorts of interesting things about electronics are posted there every day. I also invite you to my second channel Managerial Fun, where I will post memes and useful articles and materials about management, business, psychology, self-development, in general, almost all of my daily interests and hobbies https://t.me/lokicheesem.

So! The idea was to move away from battery power, switch the lamp to battery power, and also replace the conventional LED with an RGB one with remote control. It doesn’t sound complicated, but in reality it’s even simpler, because the entire circuit is assembled from ready-made modules from Aliexpress and even without the use of Arduino!

1 - toggle switch as a switch for the entire circuit; 2 - RGB LED; RGB controller complete with remote control; 4 - 30 Ohm resistors for the LED; 5 - boost DC-DC converter; 6 - type-C connector; 7 - holder for battery size 14500 (AA battery); 8 - LiFePO4 battery; 9 - tp5000 charge controller with LED included; 10 - a little twisted pair (I like to solder breadboards on it). — 1 – toggle switch as a switch for the entire circuit; 2 – RGB LED; RGB controller complete with remote control; 4 – 30 Ohm resistors for the LED; 5 – boost DC-DC converter; 6 – type-C connector; 7 – holder for battery size 14500 (AA battery); 8 – LiFePO4 battery; 9 – tp5000 charge controller with LED included; 10 – a little twisted pair (I like to solder breadboards on it).

And the connection diagram.

I was lucky that the lamp itself was made of artificial stone, easy to drill and was also hollow inside. I took it to a workshop in my city and they made me a main hole for all the electronics and a cover for it made of plexiglass with a leg on the other side so that it would not wobble, and they also drilled holes for the type-c connector, the charging controller LED and a hole for the wires , which will go to the LED. I already drilled the holes for the toggle switch and the infrared sensor from the RGB controller myself, since I forgot to ask the master about it 🙂 The connector was inserted into me directly by the workshop, it was tight)

Under the infrared sensor on the front side for better communication with the remote control

So how does the original light in the lamp work? The lamp is completely autonomous and is suspended from the lamp on a metal ring. The lampshade is removed, the light bulb unwinds and inside we see an LED even without a resistor, three batteries and a button with a lock.

We rip it all out, I also cut the bottom hole for the LED to be round, otherwise it wouldn’t fit with the top one. I made it a little smaller than the skirt of the LED, so that it would not move back and forth and would be fixed, as it was in the original design.

So that in the end it will stand up somehow like this inside.

However, I soldered everything to the wires without this plastic thing for convenience, and then with force I put it back on and the LED continued to stand fixed in the lamp. While soldering, I didn’t forget to put on the light bulb cap, otherwise there would be no way to put it back in place later.

I made a braid out of green twisted-pair wires; years of handicrafts in childhood helped me intuitively, and it turned out beautifully. I deliberately made the wiring the same green color so that it fits into the design of the entire lamp.

Then I soldered all the wiring from one end of the pigtail to the RGB controller, to which I had previously soldered 47 Ohm resistors. When I soldered the LED to the other end, I simply rang each wire so that I could understand which leg of the LED to which leg of the controller I was soldering.

This time I didn’t consider what value of resistors was needed, I picked it by eye, although when I was assembling the test circuit I looked for the datasheet for this LED and calculated the required value, but then I happily forgot everything, and I was too lazy to do it the second time 🙂 If you want to get completely confused, you can choose different resistors individually for each leg, because an RGB LED is just three LEDs inside one housing: red, blue and green, and they all consume different current. If you want the same brightness in all modes and purer intermediate colors, select resistors for each LED separately.

The connection diagram is shown above, but your controller and LED may differ from mine, in this case you can look for datasheets or assemble a test circuit and use random methods to determine where to connect what. But usually the longest leg of the LED is the power supply, it must be connected to the controller connector, which is marked with a triangle on the case, the remaining legs are responsible for each color, they must be connected through resistors.

To quickly determine the pinout of the LED, you need to turn on the dialing mode on the multimeter, hook the positive probe to the longest leg, and poke the others with the minus probe and see what color it will be.

If you mix up the legs, the wrong colors will turn on when commanded from the remote control. I also assembled a test circuit and moved the legs until I got all the buttons to correctly set the colors on the LED.

After the tests, all that remains is to solder the power circuit. From the battery, the wires go to the tp5000 to connectors B+ and B-, and the IN+ and IN- connectors are soldered to the type-c connector. And also from the battery the wires go to the boost converter. We solder a toggle switch to the positive output of the converter into the gap, the main thing is not to forget to put on the heat shrink in advance 🙂 I don’t know why I put the toggle switch exactly there, I should have put it on the positive of the battery, there will be a reason to visit my parents and fix this jamb.

When we have already soldered everything, we remember that we need to configure the booster. We need it to increase the voltage from 3.65 V from the battery to 5 V, this is the minimum required power supply for the RGB controller. We set it up with a small screwdriver, monitoring the voltage on a multimeter connected to the output of the module; I hooked up the power supply to the input, setting it to 3.65 V, simulating a battery.

I set it to a little more than 5 V.

I cut off the connector from the controller and also soldered the twisted pair. I soldered it to the output of the boost converter. I also re-soldered all the resistors, protecting them with heat shrink, which I overheated a little.