Questions tagged [led-matrix]
Anything related to LED matrices. A LED matrix is a rectangular arrangement of LEDs where all LEDs in a row have their cathode (or anode) connected to the same line and all LEDs in a column have their anode (or cathode) connected to the same line. In this way a single LED can be lit supplying power to the lines corresponding to its row and column coordinates.
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How can I calculate the power efficiency of an SMD LED? (% converted to light and % converted to heat)
I am designing an LED matrix for an LED lamp. I need to calculate the heat dissipation from all LEDs which is the dissipation of one LED times their number to choose an appropriate heat sink.
The ...
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Why Is My LED Dim Compared to Original Strobe Light?
I want to mimic the strobe drone light as in the link here and this schematic looks like the following photo.
Unfortunately, I do not know which microcontroller they used. The light is really bright ...
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Please advise if this LED circuit is efficient
I'm creating a commercial wooden lamp with LEDs. Please let me know if this design is good and efficient for long-lasting LEDs or if there is something better that I can do to power these LEDs. ...
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Driving a LED matrix with TPIC6B595 as sink and UDN2981A as current source
I am working with an 8x6 RGB LED matrix with common cathode LEDs on a PCB. I can select one column at a time by grounding its common cathode, and I source the current through the rows. The whole setup ...
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Identification of pinout on RGB LED matrix display
First thing first. I'm a beginner at electronics, but I have an LED panel I want to use for a ESP32 project. The last couple of days I have been researching for at way to connect to this panel but ...
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How to stop ghosting while multiplexing LED matrix?
I tried to make a 4*4 LED matrix and controlling it with an Arduino. With certain LED patterns ghosting occurs. On each row, the LED anodes are connected together and each row goes (from top to bottom)...
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Why there is only few multi channel high side drivers (like 8 and more) (example. TD62783AP)
I'm Currently working on a LED matrix project(5 row x 15 column) using some AVR with shift register (74HC595 to multiplexing outputs) and some low-side drivers (ULN2003A as switch to GND) and hight-...
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Why are bipolar power supplies preferred for use with OLED?
Does anyone know what are the reasons that bipolar power supplies are preferred for use with OLED?
(ELVDD is a positive voltage and ELVSS is a negative voltage)
Image source: https://eureka.patsnap....
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How can I avoid current excursion in P-channel MOSFET (high side) and BJT (low side) led matrix driver?
How can I avoid current excursion in combination of P-channel MOSFET (high side) and BJT (low side) led matrix driver? I have poor understanding of what causes the excursion and how to address it.
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Voltage drop due to traces on LED matrix PCB
Basically, does the LED matrix PCB board below have a chance to work? If not, how can it be modified to have a chance to work?
The concern is the voltage drop along the row traces. Each row must carry ...
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How to apply a thermistor to my LED driver (TLC59116 PW package)
I currently use a TLC 59116 16-channel I2C LED driver in a 4 x 4 LED array driven by Arduino and would like to add a thermistor to the circuit design. I'm unsure where to add it or what supporting ...
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What is the point of two enable signals in PT6957 LED driver?
I have a 48 x 16 matrix LED display E-MOTIVE Q-B-069B (no datasheet), and during reverse engineering I found 4 off PT6957 there.
PT6957 is 16-bit shift register, latched with constant current drives. ...
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Why am I measuring 1e6 ohm forward resistance on a functioning LED? [duplicate]
I have an LED board with a busted driver, so I thought I'd probe the LEDs to determine a good replacement driver. If I probe the LEDs I don't get a readout on the voltage drop but the LEDs light up ...
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Troubleshooting a HT16K33 + 14 segment LED showing segments when not addressed
I'm working with a board that has multiple 14 & 7 segment displays all being addressed using an HT16K33 where various segments are either not displaying or are being lit when they shouldn't.
In ...
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PWM vs mutiplexing, why one can control the apparent brightness and other saves power?
In an LED grid where we are using multiplexing to control a ton of LEDs, where we are scanning each row quickly and using persistence of vision to enjoy the full picture at once; let's say that there ...
