555 Component Finder

555 Component Finder
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While designing a frequency generator, user may know what output frequency he needs, but may not know what components values to select to get the desired frequency.

555 Component Finder finds component values for Ra, Rb and Cr to meet the frequency requirement. The tool finds standard resistor and capacitor values, so that user can get these component easily while implementing the circuit. The tool generates many combinations for a given frequency, user is suggested to select the set which suites best to his duty-cycle requirement.

555 Timer Circuit Diagram

Frequency (in Hertz) Hertz
Accuracy (in Percentage)   




SL No Ra Rb Cr Frequency (Hertz) Duty-Cycle (%)

Accuracy The tool finds component values for a given frequency taking accuracy into account. You can get more component values by reducing the accuracy.
duty-cycle = (time_high * 100)/time_period; where time_high is time duration for which output was high and time_period is one-cycle time period.