Screen flickering while hot end PWM is on November 12, 2016 11:17AM |
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Re: Screen flickering while hot end PWM is on November 12, 2016 01:17PM |
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Re: Screen flickering while hot end PWM is on November 12, 2016 02:42PM |
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Re: Screen flickering while hot end PWM is on November 12, 2016 03:27PM |
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Re: Screen flickering while hot end PWM is on November 12, 2016 03:33PM |
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Re: Screen flickering while hot end PWM is on November 12, 2016 03:44PM |
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Re: Screen flickering while hot end PWM is on November 12, 2016 04:47PM |
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Quote
icefire
What I can try is to power the RAMPS with a computer PSU and see of there is a difference. But what does this have to do with the screen? The LCD Backlight gets power from the Arduino 5V line which is connected to the LM2596S.
The hot end heater and the RAMPS get 12V through the buck converter. Since D1 is removed this has no influence on the 5V rail. So how does this lead to the screen flickering?
Re: Screen flickering while hot end PWM is on November 12, 2016 05:36PM |
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Re: Screen flickering while hot end PWM is on November 12, 2016 05:49PM |
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Re: Screen flickering while hot end PWM is on November 12, 2016 05:54PM |
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Quote
icefire
@ dc42: How could this be? The PSU, the 12V buck converter, the 5V step down module, the RAMPS, the Arduino, the MOSFET circuit for the bed heater and the PC USB have all common ground.
Re: Screen flickering while hot end PWM is on November 12, 2016 06:01PM |
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Re: Screen flickering while hot end PWM is on November 12, 2016 06:33PM |
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Re: Screen flickering while hot end PWM is on November 12, 2016 07:46PM |
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Re: Screen flickering while hot end PWM is on November 12, 2016 07:51PM |
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Re: Screen flickering while hot end PWM is on November 12, 2016 07:53PM |
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Re: Screen flickering while hot end PWM is on November 13, 2016 12:21PM |
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Re: Screen flickering while hot end PWM is on November 13, 2016 01:57PM |
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Re: Screen flickering while hot end PWM is on November 13, 2016 04:33PM |
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Quote
dc42
Unless you have servos or fans powered from +5V, the current draw from +5V should only be about 200mA. In which case, 7805 linear regulator plus two capacitors and a small heatsink would be hard to beat.
Re: Screen flickering while hot end PWM is on November 13, 2016 04:52PM |
Registered: 9 years ago Posts: 1,873 |
Quote
icefire
I have the reprap discount full graphics controller. I thought the backlight would definitely result in higher current. The AMS1117 wich is fitted on the Arduino is rated for 800mA, if the current were so small it wouldn't have been such a problem on all Arduinos...
Re: Screen flickering while hot end PWM is on November 13, 2016 05:15PM |
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Re: Screen flickering while hot end PWM is on November 14, 2016 04:17PM |
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Re: Screen flickering while hot end PWM is on November 14, 2016 04:35PM |
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Quote
icefire
... Which is why I am now feeding it 7.5V and have attached a small heatsink on top of it. But maybe it is still a good idea to play it safe and use a LM7805 instead, just to be sure...