Questions tagged [cob]
Chip on board (COB) is a method of circuit board manufacturing in which the integrated circuits (e.g. microprocessors) are attached (wired, bonded directly) to a printed circuit board, and covered by a blob of epoxy.
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Struggling to power a 20 W COB LED
I am not an engineer and have minimal electronics experience.
I am trying to build a projector for an art project and ordered a 20 W LED, a voltage regulator and a 15 V DC power supply.
No matter what,...
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How do I identify an unknown LCD controller?
Edit: I wrote a mail to Sitronix asking for docs for this controller, and they said it is ST7522, with public avalible docs.
I'm currently trying to reverse engineer a device with an MCU, LCD, and an ...
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Usability of COB LED filaments as replacement for traditional filaments
COB LED filament household lightbulbs are a thing now. Can someone explain to me what limitations there are to using these COB filaments in car headlights? They emit a very similar light pattern if ...
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COB LED unwanted blinking
I'm testing a Cree CXB1304 powered by a constant current driver Meanwell LPV-35-36
This setup makes the LED blink regularly every 2 secs, as I've read this occurs when the driver has insufficient ...
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How to use this solderless conector (50 Watts COB LED)?
I bought this 50 Watts 220v COB LED at Aliexpress:
It's solderless. The connector is in the upper left corner, but I can't figure out how to connect the wires: must I depress or lift the tabs or just ...
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What is the best way to avoid the voltage drop with a diode in this situation?
Here is essentially the schematic:
I have it mocked up and everything is great, bright and cool to the touch, but one LED array (COBs) is definitely dimmer than the other due to the very small ...
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Silicon die on Peltier device with COB wirebonding
I have a camera sensor (bare die) that must go on a very tiny PCB that also contains electronics for data serialization that dissipate enough power to make the PCB pretty hot (40-60 deg. C). I want to ...
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Is this power supply suitable for powering these chip on board (COB) LEDs?
I have an LED project using 100 Citizen CLU048-1212C4 LEDs.
I need to run each LED at 70W, and I want to run every 5 LEDs on 1 power supply.
I was thinking of using the MEAN WELL LSR-350-35 (it takes ...
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Questions about COBs and power supplies from a beginner
I'm planning to use Citizen 1212 COBs, but I don't know how they can be used on 70 watt for each one of them, knowing that each unit will have 5 COBs. So my question is: what is the right power supply ...
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Determine voltage with which to run COB LEDs
I have a few COB LEDs laying around, but unfortunately I don't know the exact model anymore.
Hence I can't read their data-sheet.
However, I would still like to use them. I own a good multimeter, and ...
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Driving 100W COB From mains using discrete components I have on hand
I was wondering if I could realistically drive a 100w COB directly from mains using a bunch of discrete components that I already have on hand.
I have a bunch of BJTs MOSFETs and E cores and I want to ...
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Relay contact insulation doesn't seem to be enough
I'm working with an ESP32 and a 4 relay module. The problem seems to be that the insulation of contacts in the relay is not enough.
Relays close perfectly and my lights turn on, but when they open, a ...
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LED diodes as both diode and load for boost converter
I'm doing an LED project with a 36V Cree CXB3590 COB LED that I intend to underpower to experiment with efficiency and learn about boost converter design. I've made a 5uH inductor with 14 gauge ...
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Constant Current Output driver connected to 2 COB LEDs - is the hookup valid?
I have a lamp with this hookup. Can someone confirm whether the electrical specs match up such that these can be connected in this way.
ld009d-cu03036-m9 - MagTech Constant Current 24-36v output ...
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Deciphering which COB LED used in a circuit [closed]
I have two lamps with identical LED circuits. The lamps sometimes blink when turning on. One of the lamps already has a blown COB LED. I suspect the wiring was done wrong. I've opened it up, but I ...
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Driving 8 x 117W COB LEDs [closed]
I am currently attempting to design a LED grow light using the following LEDs but I am having a very hard time finding a sufficient power supply.
8 x Lumileds - SunPlus CoBs
DataSheet
51.7 V, ...
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Connect VGA cooling fan (12vdc - 0.1A) to constant current driver (120Vac to 12- 22vdc @ 0.3A)
I have an AC driven COB LED which can be connected directly to the AC main in house (120v). I would like to attach a cooling fan to the COB which requires 12vdc @ 0.1A. I have a constant current ...
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How to manufacture chip on board?
I am a developer of a cheap product and i have no experience in mass production. Device is fully functional and represents a single sided PCB, a microcontroller, a bunch of diodes and a few passive ...
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COB LED Dimming via Poentiometer?
I want to create a dimmer for high power LED light's i'm building for video work. I'm using CREE CXB3590 chips, which have run at 36V with a forward current of 3.6A. I am powering these through a 150W ...
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Overcurrent Protection for COB Leds wired in parallel powered by Const Voltage Mean Well Driver
Roughly this is my current wiring diagram.
The Mean Well driver that I am using is the HLG-185H-36B. Output 36v DC, max current 5.2A. The Cobs are 36V and have a max operating current of 2.76A, ...
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Driving a COB LED, Max Current that can be Applied
I am using Luminus COB with the rating given as Maximum power 65W and typical power 29W.
At 800mA the power I would get is 29W while at 1600mA it is 65W.
When I connect it to a power supply of ...
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COB LEDs for Flood Light
I am using luminus CXM-18 COB.
The specifications in the Data Sheet read a minimum current of 800mA and max 1550mA at 800mA the power I get will be 29W and at 1550mA it is 65W while the voltage is ...
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3W 12V COB LED with 12V Campervan system
I have an LED downlight in the camper we just bought but unfortunately the module inside is dead. I would like to replace it with another LED module/chip for cheap.
The light we have: http://www.pro-...
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Powering COB LED with "under-voltage" LED driver
I have LED Driver
Model: LD-361500-105MPF
Input: 90-260VAC 50/60Hz and
Output: 20-36VDC, 1500mA+/-5%.
I connected it to the LED COB Citizen 1212C4 which needs, according to datasheet (COB's ...
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Do COB LEDs usually need electrically insulating from the heatsink?
I have some Vero series LEDs from Bridgelux. I want to put multiple LEDs on 1 heatsink. I was planning to use thermal epoxy, so there is the possibility of the aluminium base of the LED touching the ...
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ACF to mount bare die?
I've been learning about ACF for doing a chip-on-board application, but I'm having a little trouble finding enough information about it. My main questions are:
How is alignment done for very fine ...
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