Introduction: PWM and Frequency Controller (for Lasers and Diodes)
Today I will show you how to create a driver for lasers and LED that has independent pots for frequency modulation and duty cycle modulation. The main component of the driver is the 555 Timer IC. View the video to see this driver working. Between pauses I adjust the dials and I used a poor camera so the high frequency couldn't be seen. I try to spin the laser to show the frequency like I did in the picture below.
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Step 1: Get the Necessary Parts!
For this project you will need:
1X LM555 Timer
1X 220 Ohm resistor
1X 100 Ohm resistor
1X 10K Ohm resistor
3X 100K Potentiometer
1X 100 Ohm Potentiometer (2X if you wan't to have a variable voltage regulator)
1X 0.1uF capacitor
1X 1uF capacitor
1X 0.1uF capacitor
1X 220uF Capacitor
2X LM350 or LM317 Voltage Regulator (the second is optional one is for the voltage regulator and the other for the current regulator)
2X Diodes rated above 2A 10V
1X NPN Transistor (general purpose transistors work for low loads)
1X LED or Laser Diode
All of the parts can vary slightly! The diodes can be almost any type and the pots can be any value as well.
Step 2: The Schematic
Put the circuit together. If you have any questions please comment below. The new schematic is an update with a current regulator, which is also connected to a pot so you can regulate voltage and current. If you would like to have a variable voltage supply then I recommend this website: http://diyaudioprojects.com/Technical/Voltage-Regulator/. This will help calculate values.
Step 3: Other Images
These are some other images of how it looks. I plan on putting this into a project box soon. If you have any questions or recommendations please post below! Thank you for viewing my instructable.