i need to know the circuit for building a time bomb

i need to know the circuit for building a time bomb

A time bomb (or a timebomb, time-bomb) is a bomb whose detonation is triggered by a timer. The use (or attempted use) of time bombs has been for various purposes including insurance fraud, terrorism, assassination, sabotage and warfare. They are a popular feature in fictional thriller and action films as they offer as a way of imparting a dramatic sense of urgency.