RGBCW ceiling lamp (Graffiti solution)

High pressure & high temperature danger! ! !

It uses 220v AC power supply and has a large number of 310V DC wiring. Please pay attention to safety before use and beware of electric shock.

The light panel generates a lot of heat when illuminated. Do not touch the light panel as if you are afraid.

Demo video

words written in front

First of all, I am very grateful to Lichuang and Tuya. I am honored to win the second prize even though it is not completed yet. This project will continue to be updated.

Of course, as a sophomore in high school, I may not have much time to mess around, but I will try my best to fix known bugs.

Known bugs -- added

• Found an issue while using this project for the retrofit of the second lamp
• Due to dcdc chip quality issues or other metaphysical factors, the 3.3v power supply ripple is large.
• The specific performance is as follows: the module keeps restarting after being powered on.
• Solution: Add a capacitor or remove the voltage-reducing circuit and replace it with a voltage-reducing module.
• • -

〇.Update instructions

Light board

v1.02 - Modified some wiring and changed RGB to 5730 package

v1.03 - Modified some wiring, doubled the CW lamp beads, and enhanced the heat dissipation of the lamp board

v1.04 - Fixed the problem in the previous version that the screws were tightened too tightly and caused a short circuit.

2021/5/16 - Added the wiring method of v1.04 light board, not completed yet

Main control board

2021/5/6 - All the current detection resistors in the LED driver part were replaced with 0.56 ohms. After half a year of actual use, the ordinary white solder mask FR-4 board can fully support this brightness.

1. Ideas

The idea for this project came from two months ago - a fluorescent tube that had been used for five or six years finally came to an end, so I thought of making my own IoT light board.

Then it has been cooing until now

2. Hardware

The initial idea of ​​this project was to

• The light panel uses four pieces of 100mm × 100mm × 20mm × 90 degrees to form a complete 200mm × 200mm light panel.
• Use the entire light panel
  • 28pcs 5730 3000K 0.5w warm light
  • 26pcs 5730 5000K 0.5w cold light
  • 24pcs WS2812 RGB
• The main control board uses 220V AC input, the main control is ESP12S, uses two AL9910 as LED driver, and uses PWM linear dimming.

Since this training camp is based on the Tuya IOT platform, the modifications are as follows:

• The light panel uses four pieces of 100mm × 100mm × 20mm × 90 degrees to form a complete 200mm × 200mm light panel.
• Use the entire light panel
  • 8 * 4 pcs 5730 3000K 0.5w warm light
  • 8 * 4 pcs 5730 5000K 0.5w cold light
  • 14 * 4 pcs 5050 RGB //Since Tuya seems to only customize SDK development to support other RGB driving methods, the WS2812 is replaced with a PWM-driven ordinary RGB lamp.
• Main control board
  • Use 220V AC input
  • The main control is WB3S based on BK7231T
  • Use five AL9910s to drive RGBCW respectively and adopt PWM dimming.
  • Expandable human body pyroelectric sensor
  • Expandable low-power LED light module (night light)

Replenish:

* 在实际测试中，由于要手焊大量的5050 RGB灯珠会有概率出现短路
* 而使用铁板烧和手动涂锡膏会加剧这种情况的发生
* 因此v1.03的灯板将所有灯珠都改为5730封装，不仅更功率可以做的更高，用铁板烧也更好焊了( ´∀`)σ)Д`)
~~就是成本比之前高了亿点点~~

3. Software part

There’s not much to say about the software part. Thanks to the development method adopted by Tuya Smart Platform, lights like this can be directly used without development solutions. This thing is really good~

Supplement--Detailed configuration of development-free solution

• Module selectionWB3S WiFi&BLE 双协议模组
• The function points are shown in the figure below
• Detailed configuration of firmware

Since IC is used to control brightness, the minimum value of colored light can be changed to 1%

Note that the firmware used in the Tuya solution does not use night lights and infrared pyroelectric sensors.

4. Component selection

1. Main control board

• The main control power supply adopts SM7035 in sop8 package, supports 220VAC input, and the output circuit is 200MA. It is configured to output 10V, which is 2W output power, to ensure sufficient main control power supply.
• The main control is WB3S, which can be replaced with ESP12S via p2p
• The LED driver uses HV9910, which is very cheap on Taobao, 0.6 per piece with free shipping.
• LED driven high-voltage mos can use any NMOS above 400V 1A

2.Light panel

• Divide the light board into four pieces and compress the length and width within 100mm × 100mm, which is convenient for free prostitution, otherwise the PCB cost will be too expensive.
• Both cold and warm LEDs are sold on Taobao, with free shipping for 3 yuan for 100 pieces.
• The light panel is connected with a half-hole design. If you need free sex, you can note in JLC that half-holes are not required and can be made using conventional processes.

3. Shell

The outer casing is made from a lamp purchased from a certain store. Free shipping of 3 yuan + 3 yuan red envelope from the farm = free prostitution.

That's right, I'm a prostitute.

5. Transformation plan

This part records the steps to install the lamp.After all, I really lack a light

Prepare to install the lamp directly above the bed

The drilling tool is a homemade small drill bit

During the drilling process, I found that the top seemed to be metal. I was afraid of drilling into the pipe, so I drilled a shallow hole and fixed it with a large amount of hot melt glue.

Put the base of the lamp on

Put the thread in

Install magnets on the two boards, then connect the wires

Completed

6. Schematic drawing

1.Power input

• 220V AC input, connected to the rectifier bridge through the fuse and varistor, the 100uf electric dragon is mainly used for LED driver

DCDC

• Just look at the Datasheet for this part. The output voltage is determined by dividing the voltage by two resistors.

LED driver

Looking at the IC's Datasheet, you can see the typical application of this LED-driven DCDC step-down.

From the picture, you can see that you need to determine the values ​​of several resistors and inductors. If you continue to scroll down, you can see the formula for calculating Rsense.

Next, you can turn to the formula for the minimum inductance. Before that, you need to determine the frequency of the IC. Considering the subsequent inductance value, Rosc chooses 470k here.

Finally, get the value of the big electric dragon

However, I really didn’t think about this part when I was painting, so I just gave 100UF, which is basically enough.

7. PCB drawing

220V AC input

LDO buck

Replenish:

The color sequence of LED lights is as follows, the picture shows the lowest brightness (PWM is 1)

The connection sequence of the four boards is as shown in the figure. You can connect more pads for reinforcement.