Inside a German 'Volkslicht' (The people's light.) - with schematic

The Volkslicht was presented as the people's light, where the marketers probably thought that the German people would embrace their new light and buy them en-masse.
They didn't buy them en-masse and are now selling off the excess stock. Special thanks to Kai-Steffen for sending me some of these so we could explore them.

The light itself is a classic looking 6W warm white lamp with four LED filaments. The design is very typical for smart lights, with a bluetooth or WiFi module controlling the LED current regulator.
In this case the device is based on a Bluetooth module and does not need a WiFi connection, although the app does require you to sign up with your email address and a password.

In use, you create zones on your phone - like kitchen, lounge, bedroom etc. And then add lights to the desired zone by linking to their Bluetooth connection. During this process the lamps blink to indicate which one is being paired. You can then switch them on and off or control their intensity as desired.
The pairing process was actually fairly straightforward compared to some of the earlier products, and the app sent a software update to the lamp when first connected.

As with most of these smart lights, the circuitry splits into three distinct sections. The LED driver, the wireless module and a 3.3V power supply for the module. Control of the intensity is done with a PWM signal from the wireless module to the LED driver. Kai measured the PWM frequency as 1kHz. Linear regulators are ideal for this application, as they are small and simple. But with the fairly significant amount of electronics in such a small area, the lifespan will be directly affected by how brightly you run the lamp. I always recommend setting them at an intensity lower than maximum for a longer lifespan.

In hindsight, the resistive divider and LN input may be tied into the capacitor charge circuit, and may limit the voltage it is charged to. That would lower heat dissipation and allow it to auto-compensate for a wider supply voltage range.

Kai found that the bluetooth module is an EWN-8250FGT1HA which looks like a fairly capable Bluetooth mesh system on chip module.

The app seems quite "persistent" and seems to want to stay running in the background, which may impact your phone's battery run time slightly. That said, modern Bluetooth systems are much more efficient than the earlier ones. It also requires your location, probably to ensure that it is only active in areas where you have lights registered.

I think the main reason this product was less of a success than desired is that most people are happy to just switch a light on and off at the wall. The increasing amount of home automation products introduce a layer of complexity to your home electrics that will only appeal to home automation geeks (and hackers).

The Ledvance brand originates from the Osram brand and is now owned by the Chinese MLS Co.

This also keeps the channel independent of YouTube's algorithm quirks, allowing it to be a bit more dangerous and naughty.

#ElectronicsCreators

[TATICMOOR]

I can't get over how fully packed this board is with components on both sides. Hardly any real estate left, then stuffed into the end cap.

[randacnam]

The reason for the lamp drawing only 1.6W at 50% brightness vs. 6W at full is to account for the logarithmic brightness response of the human eye.

[jensschroder]

Mr. Edison marvels at how much electronics can be packed into his sockets.

[WooShell]

The D1 high speed diode might be there for EMI reasons, to block any of the switching noise backfeeding into the supply line.

[ketas]

i'm amazed the managed to fit bt into base of filament lamp

[TheGodpharma]

Much as I enjoy Clive's videos, on this occasion I wanted to know more about the gingerbread cookies. They look amazing!

[viniciusvbf]

These BP chips, from BPS (Bright Power Semiconductor) are kinda magical for me. They can transform (step down) a rectified 127V or 240V AC into a 5V or 3.3V DC, at up to 500mA. I didn't know about their existence until last january.
Downside: they're *non-isolated*. If they fail, your device will fry, too. Maybe even cause some accidents. I wouldn't recommend using them for any critical or sensitive application.
Worth mentioning than you can easily find datasheets for the models BP2525 and BP2905.

[OmegaSparky]

The pulldown on the pwm signal is to keep the lamp off while the Bluetooth module is booting up (or perhaps when it reboots)

[MyProjectBoxChannel]

I dismantled a wifi filament LED smart bulb, and it's incredibly similar! It had the wifi module with dual PWM channels, to control both warm white and cold white LED filaments. I still can't believe it all fits in the screw base.

[m.s.]

German lesson for Clive: The Vo... is pronounced here sharply like when saying >fossil<. The l then should be formed in the very front area of your mouth like when saying >pillar< The ch in Licht is a very soft sizzling sound which your throat has to be relaxed for. (The voice generator in Google Translator can be taken as a proper example.) 😉

[kyoudaiken]

In Germany, we also don't like the idea to have electronics powered on all the time ready to receive a command but doing nothing otherwise other than wasting electricity and increasing the idle power bills. You would be surprised how many switchable sockets and power strips I got going on.

[gregorythomas]

I'm kind of impressed that they were only charging ~$1 for this light...a similar one in the us would be in the vicinity of $10 at least.
I don't really like having remote controllable lights though...especially ones that connect to the internet.

[boarderk]

Love it when a video comes with snack reviews!

[JanicekTrnecka]

Ein Volk, ein Licht, Eine Energiescheisswende!

[kennyfication]

I got a few ones laying around here somewhere. At some point, my local hardware store actually gave them away for free about a year ago per 10€ worth spent at their store. Bought something for 35 bucks and got 3 of them on top. Sadly can't use them because all of my light fixtures don't have the proper socket but on the other hand, all my lights are led anyway.
Cool to see them covered here!

[TD.SteveArcs]

The wifi chip pwm output is possibly a single transistor with (open emitter) hence would need a pull down/emitter resistor

[kyoudaiken]

The high speed diode could be for interference (coming from the PWM switching harmonics) suppression that could be leaking through the full bridge rectifier diodes.

[siberx]

It's possible the separate feed path for the 3.3V regulator and rail is to make the bulb behave better if it's hooked up to a triac dimmer; the LEDs might drain the main part of the power supply to 0V in that condition, but as the 3.3V has its own capacitor and diode (and draws little current) it would have an easier time remaining powered, preventing resets of the bluetooth chip.

[ralphshoop]

What is the story behind the term "death beam capacitor" Clive?

[johnf]

Clive does ASMR and impressions. Is there any limits to this man's talents?!