From 55c7b1cd2cdee2671456a5f487442bfe795fb086 Mon Sep 17 00:00:00 2001 From: Jan Sucan Date: Sat, 3 Dec 2022 19:45:08 +0100 Subject: Add README --- README.md | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) create mode 100644 README.md (limited to 'README.md') diff --git a/README.md b/README.md new file mode 100644 index 0000000..08ed08b --- /dev/null +++ b/README.md @@ -0,0 +1,34 @@ +# Regulator of 4-wire PWM fans + +The article was published in April 2018 in Czech magazine [Praktická +elektronika - Amatérské Radio](http://aradio.cz). It is written in Slovak +language. + +The article describes construction of regulator for a 4-wire PWM fans. I have +built it because I needed to cool my laptop which was overheating under heavy +CPU load. + +When switched on the first time the regulator performs calibration of RPM +indication. It measures maximal and minimal RPM and uses this range information +for indicating RPM by LED bar. This information is saved to the EEPROM of the +MCU so the calibration don't have to be performed the next time when the +regulrator is switched on. Calibration can also be forced by keeping the button +pressed when switching on the regulator. + +The regulator has four modes for indicating approximate RPM of the fan. User can +cycle through these modes by pressing the button. +- Set RPM +- Real RPM +- Set RPM with auto-off of the LEDs +- Real RPM with auto-off of the LEDs + +Auto-off means that when RPM does not change for a few seconds the green LEDs +are switched off and only the first green LED is on with low brightness. LEDs +are switched back on when a significant change of the RPM occures. Significant +change is change in the RPM that would lead to change of the LED's states in +non-auto-off modes. + +![Title page](article/aradio_0.jpg) +![Page 1](article/aradio_1.jpg) +![Page 2](article/aradio_2.jpg) +![Page 3](article/aradio_3.jpg) -- cgit v1.2.3