Hi all! I'm trying to control 8 LEDs (later up to 32) connected to a 12v source. I also want to be able to change their brightness. After some research, I decided to carry on with a TPIC6B595 Shift Register and PWM. The problem is that this is my very first project (I was just playing before with 74…

The chips Vcc pin needs to be connected to the Arduino 5v pin. There should also be a decoupling capacitor on this pin to GND (0V). 100nF ceramic

There is no power connection to the I.C. [image] [image]

Hi, @dworza Welcome to the forum. Thanks for using code tags.. :+1: :+1: [image] dworza: decided to carry on with a TPIC6B595 Shift Register and PWM. How do you aim to PWM through a shift register? This would be better and easier to code. [image] Adafruit 24-Channel 12-bit PWM LE…

Thanks for a quick response LarryD! If I'll connect the Vcc pin on the Shift Register to the 5V pin on my Arduino, then the intensity of the LED will never change and will always stay at the max. brightness. I thought that if I'd like to control the brightness through the PWM, I need to disconnect t…

[image] dworza: TPIC6B595 [image] Connect the G’ pin to an Arduino PWM PIN.

[image] TomGeorge: How do you aim to PWM through a shift register? My idea was to analogWrite to a G pin. I saw a similar example for 74HC595 and thought that it should also work here. [image] TomGeorge: This would be better and easier to code. It might be easier but I already bought …

[image] dworza: My idea was to analogWrite to a G pin. Yes, connect the G’ pin to an Arduino PWM pin.

[image] LarryD: Arduino PWM PIN. I connected G to pin 11 on Arduino, changed it in the code const int GPin = 11; But the LEDs won't light up (unless I'd connect directly Vcc with 5v on Arudino). Is there a problem with the code maybe?

[image] LarryD: 100nF It works! Thanks, @LarryD , you made my day! I honestly didn't know that not all the pins on Arduino can be used for PWM.

Hi, @dworza [image] dworza: My idea was to analogWrite to a G pin. I saw a similar example for 74HC595 and thought that it should also work here. Even with the 595, you can only change the state of any channel, one at a time. So if you are say 50% PWM CH1, when you go to CH2 to PWM its outp…

Basic set-up for TPIC6B595 Shift Register with PWM

Other Hardware LEDs and Multiplexing

dougp January 9, 2023, 3:13pm 12

The pins with a tilde (3, 5, 6, 9, 10, 11) are hardware-capable PWM pins. See post #3:

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Basic set-up for TPIC6B595 Shift Register with PWM

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