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Minimalist LFO Design

This LFO is 2.5*5cm big and provides a powerfull, gate triggable LFO to any of your design. Just plug in a 5V and watch the monitoring LED glow as your 0↔5V LFO is fed to your favourite synth. Here's the design !


This LFO has the following characteristics :

  • Output swing from 0 to 4.8V
  • Frequency from 0.5 to 10Hz
  • Faded LED to visualise the LFO State
  • Reset on the rising edge of a 5V Gate signal
  • Low component count


V1.0 - 05/02/2013


The LFO is based on an ATTiny45/85 microcontroller.

  • Analog Input on Pin 3 reads the “Rate” control, voltage from 0 to 5V
  • Triangle Waveform LFO Waveform is generated by the Microcontroller
  • LFO Output on Pin 5 (PWM Fast Mode) is filtered by R1/C1 to generate the 0-5V peak Triangle output
  • AMP control potentiometer controls the amplitude of the LFO Output
  • LED brightness is controlled by PWM as well


The Miniature 2.5x5cm PCB allows this LFO to be integrated in any design. Board connector is as follows :

  • 1: 5V
  • 2: Gate
  • 3: GND
  • 4: LFO Output

Design Files

Made with Eagle CAD Free version. Download :


Programmed using Arduino IDE for ATTiny mod. SW is currently under dev. Working demonstrator on breadboard, formal release “when ready”.

minimalist_lfo.txt · Last modified: 2018/08/26 09:36 by - Licence Creative Commons