NE555 Square Wave Generator Module with Adjustable Frequency and Duty Cycle

Output Signal and Adjustment This NE555-based module generates a square or rectangle wave signal with an adjustable on-cycle, giving you flexible control over the output waveform. The output amplitude ranges from 4.2V V-PP to 11.4V V-PP, though the exact level will vary depending on the input supply. The duty cycle and frequency are not adjusted independently; instead, altering the switch-on cycle changes the frequency accordingly, allowing straightforward fine-tuning of the output pressure cycle. Output Current and Indicator The module delivers a maximum output current of 15mA when powered from a 5V supply with a V-PP greater than 50%, and approximately 35mA when running from a 12V supply under the same conditions. A built-in LED provides clear visual feedback: it lights up when the output is low, switches off when the output is high, and flashes at lower frequencies so you can monitor operation at a glance. Practical Applications This compact generator is well suited for driving stepper motors and other projects where a square or rectangle wave signal with adjustable timing is required. Its simple control scheme makes it easy to integrate into breadboard setups, test rigs, or custom electronics builds where precise waveform shaping is needed.