Sparkfun 555 Timer

• Sparkfun 555 Timer
• Offers timing from microseconds to hours
• Provides astable or monostable operation
• Features adjustable duty cycle
• TTL-Compatible output can sink or source up to 200 mA

The Sparkfun 555 Timer is a common 555 timer/oscillator from Texas Instruments. A classic for all of those first-year circuits projects where you need to blink an LED, generate tone, and thousands of other great beginning projects. Google around for a huge list of resources and example projects.

This timer can be used for several applications as Fingerprint- and Iris-Biometrics or an RFID-Reader.