IC 555 is most widely used general purpose timer IC. A host of application notes, magazine articles, and even kits are on the market for many different application of the IC 555. The timer ICs 555 and 556 can operate either as a monostable (one-shot) or an astable (multivibrator) circuit. The highest frequency at which astable operation is possible is 100 kHz
Application of Timer IC 555 and 556 are:
Accurate timing, sequential timing, time-delay generation, pulse generation, pulse-width modulation, pulse-position modulation, missing pulse detection and clock application of all types.
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