555 Timer IC Pin Diagram, Modes, Circuit, Working, Datasheet
TLC551 IC Timer - CMOS 555 with 1V to 15V power, up to 1.8MHz [TLC551CP] : ID 5222 : $3.95 : Adafruit Industries, Unique & fun DIY electronics and kits
555 Timer IC - Features, Pinout, Working, Circuit, Operating Modes
555 Timer IC Pin Diagram, Modes, Circuit, Working, Datasheet
555 timer IC - Wikipedia
Fifty Years of the 555 Timer IC | Elektor Magazine
IC 555 Timer Calculator with Formulas and Equations