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Re: Turning on and off AC MR16 LEDs with logic level DC
Ah interesting, I was thinking these LEDs were buck converters but a boost converter would be equally a legitimate solution...
Now whether the rectifier can stand 100% duty cycle DC is the next question...Comment
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Re: Turning on and off AC MR16 LEDs with logic level DC
it will be 1A atleast.
as for dc/ac the frequency of mains really isnt fast enough to make a difference to the diodes current handling.Comment
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Re: Turning on and off AC MR16 LEDs with logic level DC
Well, if they are all 1N4001s that support 1A continuous, a bridge, two of the diodes would be conducting half of the time. So the average current for each of the pairs would be only half amp as they would not be conducting half of the time, and the RMS power dissipation would be 0.7V * 0.5A average = only 0.35W compared to now, 0.7V * 1A = 0.7W - double the power. Plus heat generated could derate the diodes.
So it depends on how the rectifiers are made, if they used something other than 1N4001s then it would be better. I saw a couple designs using 1N5820s which would give much more headroom, but the premise is still there.Comment
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Re: Turning on and off AC MR16 LEDs with logic level DC
The way the unit is sealed like that, I will doubt that it will properly dissipate the heat.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809Comment
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Re: Turning on and off AC MR16 LEDs with logic level DC
The Philips glass LED MR16 I got at Home Depot. Can't remember if 35W. Their old style has a bunch of small LEDs while the new ones went single COB, across the board in their floodlights and spotlights. The COB sucks because it is very narrow angle and not as bright. But the CRI is the best I've seen. Cree products are no longer in HD stores.
I also got GU10 for mains power instead of 12VAC. The Ikea 7.5W 600lm GU10 is also very good but 2700K a bit warmish. 17 leds and also uses bridge rectifer.Comment
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Re: Turning on and off AC MR16 LEDs with logic level DC
Well, the GU10 is completely different, it's more akin to A19 bulb systems, which we're forced to use isolation anyway and thus making this thread go off a tangent by eliminating the H-tree and open collector/drain solutions...
The 1G Soraa MR16 has a single very bright unit AFAICT. It's a 50W replacement and is significantly brighter than a 20W halogen MR16 that I have. I also have another newer MR16 LED which also claims to be a 50W replacement - it is very bright too, but just a tad dimmer than the Soraa but uses less power. I can't really tell the light output difference without a light meter. Both have similar beam output.Comment
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Re: Turning on and off AC MR16 LEDs with logic level DC
I think all AC-powered LED bulbs use a bridge rectifier up front, so DC operation would be possible. "dimmable" verses "non-dimmable" is an issue.
Soraa: "Works with trailing edge and leading edge phase cut dimmers, 12V AC magnetic and electronic transformers and 12V DC transformers"
Are you wanting to use AC or DC to power the LED bulbs?
I think the options so far:
1. Use a relay or triac on primary or secondary of the step-down transformer
2. MOSFET SSR on secondary
3. Use a BJT/MOSFET after a rectifier giving DC to the lamps.Comment
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Re: Turning on and off AC MR16 LEDs with logic level DC
"12V DC transformers"... hah.
Well that's the question post in the original post, suppose I had both 12VDC and 12VAC available, which is the cheapest (primary goal; also considering damage to the LED lamp module if DC can damage the rectifiers due to 100% duty cycle) and correspondingly most efficient way (in terms of power waste) as a secondary goal to power and control them.
I'm just a bit concerned because the lamps do not explicitly say AC/DC, they just say AC.Comment
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Re: Turning on and off AC MR16 LEDs with logic level DC
They're bridges for sure, since I can turn the DC around and it will still light!Comment
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Hi there !
I'm having an issue for several weeks with my quite old K70 LUX RGB keyboard. I haven't used it for few months, and once I setup up again my desktop computer, I got several dead LEDs on that keyboard. I tried the Corsair troubleshooting thing (disabling options in iCUE, ...) but nothing changed so I conclude that for some reason some LEDs went in retirement...😅
Decision taken to change these LEDs as I have access to desoldering iron and binocular magnifier, I wrote a ticket to tech support, hopping to obtain the LEDs reference and... They refused to tell me 🙄...10-08-2024, 11:58 AM -
This specification for the Acer TravelMate P2510-G2-M-54Q3 + Option Pack Notebook can be useful for upgrading or repairing a laptop that is not working. As a community we are working through our specifications to add valuable data like the P2510-G2-M-54Q3 + Option Pack boardview and P2510-G2-M-54Q3 + Option Pack schematic. Our users have donated over 1 million documents which are being added to the site. This page will be updated soon with additional information. Alternatively you can request additional help from our users directly on the relevant badcaps forum. Please note that we offer no warranties...09-06-2024, 08:00 AM
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I hope this is the right forum to post in despite not technically being a repair, but still a question of swapping boards.
I thought I'd explore the possibility to upgrade an existing working Samsung ue55nu7096u with the logic board (and power board if needed) of a newer model (ue55ru7105k) of the same size and appearance (and resolution). The reason being I'd like the extra inputs of that board including component in, an extra HDMI port and bluetooth. Its panel is broken so I have no use for the board otherwise.
The models launched in 2018 and 2019 respectively.... -
Hi everyone! I'm trying to fix my black screen / failed U8900 GPU v-core on my Mid-2012 Macbook Pro 15" Retinaby doing a rework/reflow of the chip (once I determine that's the real issue; but it likely is).
I've been disabling the GPU in NVRAM for a few years... but it's just time for a better solution.
I'm new to soldering but the only feasible way to fix this issue is to do something myself.
MY QUESTION:
I've been seeing some people (on this forum mostly) run into issues with the logic board needing a serial number or it being deactivated (?)... -
So I use this TV daily as a second monitor for my PC or my Playstation - at one point a few months back I tried to fix the problem - but in the process, I figured out something that works so I haven't posted this for awhile. It is an annoying trick to have to do though, so I decided to post about it to see if anyone could spot what's wrong. It baffles me because it works on it's own half the time.
When I first got this TV, I was told it wouldn't turn on, and of course I did the flashlight test, and the image was there. Also, the red LED on the front indicated that it had power (it...
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