switching - Removing voltage spikes and overshoots using power MOSFET as switch and 555 timer as pulse generator - Electrical Engineering Stack Exchange
The 555 Astable Circuit - More Detail
555 Variable Frequency pulse generator LM555 Variable Frequency pulse generator - 555-556 Timer info Elektropage.com
555 Timer PWM Generator Circuit Diagram
555 Pulse Generator Module, How It Works : 8 Steps (with Pictures) - Instructables
How to Build a Sine Wave Generator with a 555 Timer Chip