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A very interesting lamp that uses a HUGE array of standard surface mount LEDs wired as 66 parallel strings of ten series LEDs. The use of multiple parallel circuits of ten LEDs seems to be a very common driving technique, as used in most of the 20-100W LED floodlights.
The driver is surprisingly chunky in this lamp, and has a lot of interference suppression circuitry on both the incoming mains and the outgoing DC to the LEDs.
Demo of lamp at https://www.youtube.com/watch?v=j7Dq2myAN7Y
The main control chip is an SN03A driver chip dedicated to the function of driving LED lighting loads with very good power factor. It doesn't seem to use significant smoothing on the incoming rectified mains, but rides the waveform, switching the transformer with a single MOSFET. The transformer has a second winding on the primary side to power the chip itself after it has started running. Current in the primary is monitored on each switching cycle via a sense resistor in series with the MOSFET.
There is opto-isolated feedback from the secondary side with efficient low-loss current detection being implemented using an LM258 op-amp. The secondary rectification and smoothing is based around a TO220 style diode package on a heatsink and two paralleled smoothing capacitors.
There is an auxiliary secondary winding on the transformer for a cooling fan (not fitted on this model), which uses a single rectification diode and a 22uF capacitor to create a simple unregulated DC supply.
The LEDs are probably run at a current of 1200mA split across 66 parallel circuits, giving a typical LED current of around 18mA.
A very interesting lamp that uses a HUGE array of standard surface mount LEDs wired as 66 parallel strings of ten series LEDs. The use of multiple parallel circuits of ten LEDs seems to be a very common driving technique, as used in most of the 20-100W LED floodlights.
The driver is surprisingly chunky in this lamp, and has a lot of interference suppression circuitry on both the incoming mains and the outgoing DC to the LEDs.
Demo of lamp at https://www.youtube.com/watch?v=j7Dq2myAN7Y
The main control chip is an SN03A driver chip dedicated to the function of driving LED lighting loads with very good power factor. It doesn't seem to use significant smoothing on the incoming rectified mains, but rides the waveform, switching the transformer with a single MOSFET. The transformer has a second winding on the primary side to power the chip itself after it has started running. Current in the primary is monitored on each switching cycle via a sense resistor in series with the MOSFET.
There is opto-isolated feedback from the secondary side with efficient low-loss current detection being implemented using an LM258 op-amp. The secondary rectification and smoothing is based around a TO220 style diode package on a heatsink and two paralleled smoothing capacitors.
There is an auxiliary secondary winding on the transformer for a cooling fan (not fitted on this model), which uses a single rectification diode and a 22uF capacitor to create a simple unregulated DC supply.
The LEDs are probably run at a current of 1200mA split across 66 parallel circuits, giving a typical LED current of around 18mA.
So much nicer than chineseum junk
Oh nice they actually run the leds at 20mA
The 'bootstrap winding' that power the switchmode controller once it's started up can also be used to detect the secondary voltage simply by turns ratio.
I got some think like this 10 + years ago, it was equivalate to a 150w bulb, it lasted 3 months, then blow up, it got to hot,
i love dat shit
I remember this video and you talking about the apprenticeships and I commented on my old Channel That's now band however I realized something. You know who makes even more money than electrician? That would be a police officer because a police officer in California usually on average makes around 200,000 to 300,000 a year.
electricians make nowhere near that amount of money but you know what at least you still have a soul after your apprenticeship something that you don't have once you become a police officer.
Looks like some odd 'toy' Pamela Anderson would keep in her handbag
just add 6 more leds and it becomes the devils lamp especially if it was in red lol
Have you shown a capacitive dropper powered AC configuration of a led device , IE no DC at LEDS ?
No Hopi…. 🙁
I believe these are spray booth lights not cheap pieces of kit. I have some 100w ones in for repair. They have a 12v fan and the pcb seams to be the same arrangement with more parts, like temperature sensing etc.. still no feed back tho. There designed for an open fixture due to heat. I'll try fill in the gaps as i progress, because it definitely seems like a repair is feasible due to there high cost.
bigclive. sofa king funny,,, the "no cake for you" comment and the math test,,,, drive them crazy
Is this the quality corn cob LED light bulb I've been looking for? What about light performance, power consumption and color range?
what kind of PF did this unit get?
Need to bolt 6 more of the things on somewhere.
That ventilation hole inside looks like a place for a fan tho.