Hi,
I have bought a Mini-6-LED-Chaser from Velleman (https://www.velleman.eu/products/view/?id=366626).
I do not understand how they have optimized the LED part. They do not use common ground, to reduce the number of resistor (only 3 instead of 6, see figure).
I figured out the main idea that is with only 3 inputs you can command 6 LEDs (2^8-2 (the case of A&B&C=0||1, nothing happens)).
However, I do not understand why there is only one LED ON at a time. This is what I have :
If A=Vcc, B=0, C=0 => LED1, LED5 should be ON
If A=0, B=Vcc, C=0 => LED2, LED4 should be ON
That is not that I can observe on the board. Only one LED is ON but I do not know why.
If someone can explain me what I am doing wrong. Thank you.
I have bought a Mini-6-LED-Chaser from Velleman (https://www.velleman.eu/products/view/?id=366626).
I do not understand how they have optimized the LED part. They do not use common ground, to reduce the number of resistor (only 3 instead of 6, see figure).
I figured out the main idea that is with only 3 inputs you can command 6 LEDs (2^8-2 (the case of A&B&C=0||1, nothing happens)).
However, I do not understand why there is only one LED ON at a time. This is what I have :
If A=Vcc, B=0, C=0 => LED1, LED5 should be ON
If A=0, B=Vcc, C=0 => LED2, LED4 should be ON
That is not that I can observe on the board. Only one LED is ON but I do not know why.
If someone can explain me what I am doing wrong. Thank you.
