NE555 Signal Generator Module - Adjustable Frequency and Duty Cycle

This pulse generation module, based on NE555, produces adjustable square waves within selectable frequency ranges, with duty cycle control. It is ideal for testing Microcontroller Units (MCUs), operating stepper motors, and generating waves in electronic projects.

Features:

• Adjustable square wave pulse output
• Selectable frequency ranges:
  • LF: 1Hz ~ 50Hz
  • Lo: 50Hz ~ 1kHz
  • HF: 1kHz ~ 10kHz
  • UHF: 10kHz ~ 200kHz
• An LED indicator on the board reflects the output status (Low = On, High = Off, Flash = Low frequency)
• Operates with DC input from 5V to 15V
• Easy frequency/duty adjustment using RA and RB voltage scales (0–10K)

Specifications:

• Input Voltage: 5V – 15V DC
• Input Current: ≥100mA
• Output Voltage: 4.2V – 11.4V Volt-PP (varies with input voltage)
• Maximum Output Current: ≥15mA (at 5V), ≥35mA (at 12V)
• Timing Formula: T = 0.7 × (RA + 2RB) × C
• Capacitor Selection:
  • LF: 100μF
  • Lo: 1μF
  • HF: 0.1 microfarad
  • UHF: 0.001μF

Applications:

• Square wave signal generation for development/testing
• Pulse generator for stepper motors
• Simulation of MCU pulse inputs
• Adjustable pulse control circuits

Note: Please turn off the power before switching frequency settings.