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.
26
questions
1
vote
2
answers
84
views
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,...
- 11
1
vote
1
answer
155
views
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 ...
- 103
1
vote
4
answers
96
views
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 ...
- 13
0
votes
1
answer
388
views
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 ...
- 1
0
votes
2
answers
165
views
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 ...
- 209
4
votes
3
answers
825
views
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 ...
- 57
3
votes
1
answer
182
views
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 ...
- 91
1
vote
3
answers
1k
views
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 ...
- 27
0
votes
1
answer
51
views
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 ...
0
votes
2
answers
1k
views
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 ...
0
votes
0
answers
101
views
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 ...
- 151
4
votes
2
answers
408
views
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 ...
4
votes
2
answers
389
views
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 ...
- 4,143
0
votes
1
answer
167
views
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 ...
- 187
0
votes
1
answer
153
views
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 ...
- 187