[W600 / AJ-05] Bakibo TB95 9W 1000lm RGBCWW Light

Hello!

I recently came across this board while looking to convert an Aubess/Tuya relay to OpenBeken... And I was wondering what was making my smart lights tchuutchuu! So please join me in this teardown and modding journey

I bought these lights back in 2019 from Amazon France. They are not available anymore, this link is only for reference. The build quality is good, the body is made of plastic and aluminum. It is compatible with Google Home and Alexa but you need the Smart Life app... Which I'm not a fan of.

The white dome is held secured to the housing with 2 or 3 dots of glue. Simply twist the dome to break the joints, and unclip it from the housing when it starts rotating. The electronics are made of 3 pieces: the LED board, power supply, and driver board. The LED board is held secured to the housing with 3 small screws and a bit of glue: unscrew the screws then use a dental pick or a small flat screwdriver to pry the board up to break the glue joints. Upon reassembly, I would add some thermal paste where the board meets the housing to help dissipate the heat. The driver board sticks through the LED board... Push against it with your thumb while pulling the LED board to keep the power supply + driver boards inside.


The driver board is soldered to the power supply. By the way, the power supply looks to be a real switching power supply, which is way better than what you can find in an Aubess/Tuya relay! There might be high voltage in there so be careful, but you could connect a USB-TTL converter to the driver board without fearing of frying your USB-TTL or computer. Back to the driver board, it is identified as "AJ-05" on the back, where you can also see the pinout! That's so convenient
(left to right)
- GND
- PB8/WW
- PB18/R
- PB16/G
- PB15/B
- PB13/CW
- VCC (3.3v)
The board hosts a Winnermicro W600-A800 microcontroller datasheet here.


We can see 3 test pads on the driver board next to the W600 chip, this is where it gets interesting
- TX1 = PA4 - UART0_TX
- TX2 = PA5 - UART0_RX
- TX3 = TEST (useless for us)
In other words... Would you want to connect this lamp to a USB-TTL converter this is what you would want to do:


Ok... and now what? Well now we can flash our favorite OpenBeken app on the chip, and unleash the potential of the light bulb! Well... kind of... more on that later.

I started using vshymanskyy's w600tool software. Since the reset pin is not readily available on the driver board, we can briefly disconnect then reconnect the ground pin to reset the device when w600tool asks for a reset. Let's say your USB-TTL is known on your computer as COM8, first let's check if we talk the same language as the chip by reading its MAC address:


If the output looks decent, let's continue and flash the chip! At this point, I realized there was another tool from OpenBK team that could be used to flash the chip and I think that's the one I used... The OpenW600_xxxxx.fls file was downloaded OpenBK2731T_App releases page on Github, look for the W600 UART flash file.


Reboot the device, and you should see a new Wifi popping up around you called OpenW600something. Connect to it, browse to http://192.168.4.1 and configure the device to match your wills (wifi, mqtt...). Then, configure the pins:


With these settings, each color has its own channel. However, there is an issue: they are not dimmable. They are either on or off. I tried playing with the settings to get some PWM working but I couldn't get any working results. OpenW600 does not even support PWM on all pins... I'm pretty sure the hardware is capable of outputting PWM on those pins because there is no driver down the line toward the LEDs, only humble transistors. So I guess some modifications would be required on the firmware, I'll look into that later.
Anyways! Now the light bulb can be reassembled and updated using the OTA feature of the OpenBK/OpenW600 firmware.