Rotary Encoder Debouncer

Debouncing an EC11 rotary encoder is not easy. I found a useful circuit here. I basically built the same thing for myself. The circuit diagram comes from the data sheet of the SN74LVC1G14 IC and I will use the component values as in the project mentioned above.

If you wish, you can build your own circuit boards at your own risk. A link to the files required for an order from JLCPCB (or another manufacturer) can be found at the end of this article. All components are 0805 SMD and the ICs have a SOT23 package. The PCB size is 22 x 15 mm.

 

 

Download debouncer files 

 

My project is free for private use. It is aimed at experienced people. I take no guarantee! Duplication is at your own risk and responsibility!

Little ATmega 328 Board (Arduino Nano compatible) with 2 power MOSFET´s

My next project is on the way. It's (as almost always) an Atmega328 board again. This MCU still meets almost all of my requirements and it is cheap to buy. The dimensions are only 40mm x 50mm.

On the board there is again a power supply for 5V (buck regulator). I did not use reverse polarity protection because this is not absolutely necessary due to the use of a power input socket (but If the power socket is not to be used, a screw terminal can also be installed). There is also an EEPROM as well as a 9 mm buzzer and connection options for a USB / TTL converter and I2C bus.

The special feature are 2 Power MOSFETs. These are controlled by a LowSide MOSFET driver in order to achieve good switching behavior with very short pulses (PWM duty cycle close to 0% or 100%). I also hope that this will reduce the power loss (heat generation), because each of the MOSFETS should be able to reliably control 3A at 1kHz PWM (this is the maximum for the JST sockets and the thickness of the conductor tracks are dimensioned that way). The operating voltage is 7V - 18V (the limiting factor is the used MOSFET driver (MIC4427: 18V)).

 

 

 

 

My KiCAD project files can be downloaded from my Google Drive.

 

 

KiBoard4.zip
MD5: 66CA7C3D6ED62249DBB1EDCADB2F57A1
SHA256: 30567949E02D2276559D1115135B24047BAA9E08B93609C10C0325357B58657E

There is another archive in the ZIP files. This can be uploaded directly to a board manufacturer (I use Seedstudio or JLCPCB) to order professional PCBs in your desired color.

My project is free for private use. It is aimed at experienced people. I take no guarantee! Duplication is at your own risk and responsibility!

You are welcome to customize or modify my project and publish it. However, you always have to refer to the origin!

KiBoard 3, again an Arduino Clone

The year 2020 is almost over now. Unfortunately, my job is very busy during the COVID19 pandemic. Today (October 2020) I have a real vacation for the first time this year. I used the time and developed 2 boards. Not really anything new. It's Arduino compatible boards with Atmega328 again. They contain a buck regulator, 3.3V LDO regulator, EEPROM, buzzer and an RTC (DS 1307 or DS3231). These boards are designed to be mounted with spacers on the back of a 1602 LCD display, which contains an I2C adapter. I decided again for an I2C display and deliberately did not choose a parallel connection because it "eats up" too many pins.
A UART header is available to connect a USB converter.

I ordered only the boards for the DS3231 version from JLCPCB. I did not order the version with the DS1307 and will test it at a later date.

Today I got the PCBs from JLCPCB. I then assembled and tested 3 boards of the DS3231 version. It all looks very good. The board fits perfectly on the back of my 16x2 LCD display and everything seems to be working.
Fortunately, it contains protection against reverse polarity of the operating voltage (7 - 24V). Otherwise I would probably have grilled one of the circuit boards :-) ...

My KiCAD project files can be downloaded from my Google Drive:

There is another archive in the ZIP files. This can be uploaded directly to a board manufacturer (I use Seedstudio or JLCPCB) to order professional PCBs in your desired color.

My project is free for private use. It is aimed at experienced people. I take no guarantee! Duplication is at your own risk and responsibility!

You are welcome to customize or modify my project and publish it. However, you always have to refer to the origin!

 

Update 2/2021

I have finished my device. I added two p-channel power MOSFETs. Now it controls the lighting in my aquarium. The special thing is that I can now control the colors blue and white of my lighting separately. Now my fish have a blue night light and daylight that is accurate to the minute. And all of this is softly dimmed without stress.