Dr Ronald Stiffler SEC technology

[gyulasun]

I found the logic circuit of my led lamp, see picture.
The backside reads:  Y&M-TG-5-9W  so probably indeed a 9W led lamp.

Itsu

Hi Itsu,

Yes, the 5050 LED chip is designed for the 60 mA forward current and 3.1 - 3.4 V forward voltage and this roughly
gives 0.2 W power (each chip includes 3 LEDs in parallel with 20 mA current for each LED).  The 0.5 W version in this
chip family is labeled as 5054, so it is already a different type.The converter you show very likely provides a constant
current drive for the 3 LED boards in the lamp and I think the 3 boards are in series connection.
This way the constant current is 120 mA and the total voltage should be then 3 times the 23 V = 69 V DC,
this gives roughly 8.3 W power what the converter should provide.
Assuming a normal 90 % efficiency for such converter, the mains input power should be around 9.1 W into the converter.
Now what would be interesting is to feed a single such LED board from about 23 VDC source to let 60 mA current
flow and see the brightness as a reference for the oscillator...   
Gyula

[gyulasun]

Lidmotor - I build the crystal oscillator circuit with BD243C transistor. the transistor isn't get hot and stay cold
with 24 volt input. the current output from DC DC boost converter is 24 mA so 24*24= 576 mW

Hi Erfandl,

Good job with the crystal oscillator. If I see from the pictures correctly, you drive the LED via a single wire coming
from the single layer coil, right?  Did you connect the single wire to the back plate of the LED board?
Would you tell what is the type of the LED board or lamp? (make, power). If you happen to have a second such LED lamp,
then could you drive it with a known DC power to get a similar brightness the oscillator provides?
Thanks, Gyula

[Lidmotor]

Slider---I might go out tonight and stick a flashlight in the ground to honor the guy.  Tesla---born July 10, 1856

[erfandl]

Hi Erfandl,

Good job with the crystal oscillator. If I see from the pictures correctly, you drive the LED via a single wire coming
from the single layer coil, right?  Did you connect the single wire to the back plate of the LED board?
Would you tell what is the type of the LED board or lamp? (make, power). If you happen to have a second such LED lamp,
then could you drive it with a known DC power to get a similar brightness the oscillator provides?
Thanks, Gyula

thanks for reply. yes the LED drived with single wire. the wire is connected to diodes not back plate. I think its 7 watt LED ( I don't know voltage maybe 120 volt ? ). I cant remember model of the bulb
the brightness is go higher when I connect the DC DC boost converter heat sync to a big aluminum heat sync.

[itsu]

Hi Itsu,

Yes, the 5050 LED chip is designed for the 60 mA forward current and 3.1 - 3.4 V forward voltage and this roughly
gives 0.2 W power (each chip includes 3 LEDs in parallel with 20 mA current for each LED).  The 0.5 W version in this
chip family is labeled as 5054, so it is already a different type.The converter you show very likely provides a constant
current drive for the 3 LED boards in the lamp and I think the 3 boards are in series connection.
This way the constant current is 120 mA and the total voltage should be then 3 times the 23 V = 69 V DC,
this gives roughly 8.3 W power what the converter should provide.
Assuming a normal 90 % efficiency for such converter, the mains input power should be around 9.1 W into the converter.
Now what would be interesting is to feed a single such LED board from about 23 VDC source to let 60 mA current
flow and see the brightness as a reference for the oscillator...   
Gyula

Gyula,

i can measure that the 3 outputs on the circuit board to the 3 led boards are parallel.
So i believe all 3 led boards get normally around 23V.

For comparison on the oscillator driven board (50mA) and a PS (20 - 23V @ 67 - 160mA) driven board see the video:

https://www.youtube.com/watch?v=iNdXiOw2Sbs

Itsu