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Discussion Starter · #1 ·
20165

In this circuit, the IO port of the single-chip microcomputer is connected to the OUT1 of the MOC3021. I want to change the duty cycle to control the brightness of the lamp by adjusting the output of the IO port. On for 1ms, off for 9ms, on for 10us, off for 1000us, etc., there is no difference between the brightness of the available light and the brightness when the MOC3021 is always on. I don’t know anyone who has done SCR dimming.
Could anyone give me some suggestions?
Thanks a lot!
 

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I built an LED strip light controller from a Raspberry PI, an I2C Pulse Width Modulation chip and some MOSFETs - with digital level inputs. I posted basic details about it in this post - Somewhere in West Yorkshire in the 1950s

A quick re-read of the post says the I2C chip was used because the Raspbian OS got in the way of proving good pulse width modulation of the Pi's I/O pins.

David
 

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Discussion Starter · #3 ·
I built an LED strip light controller from a Raspberry PI, an I2C Pulse Width Modulation chip and some MOSFETs - with digital level inputs. I posted basic details about it in this post - Somewhere in West Yorkshire in the 1950s

A quick re-read of the post says the I2C chip was used because the Raspbian OS got in the way of proving good pulse width modulation of the Pi's I/O pins.

David
Hi, David.
Thank you for your reply.
Your article is awesome. I am now clear on how to do that.

Thank you so much.
Trendy.
 
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