LIMITER CIRCUIT

PROBLEM TO BE SOLVED: To prevent the occurrence of a large rush current, and estimate the factor of safety of electronic parts used for load low, by boosting the voltage to be outputted to load side at power ON in two stages. SOLUTION: This limiter circuit regulates the potentials on the base side of the first and second transistors Q1 and Q2 getting over the specified voltage by the second Zener diode Z2, thus this regulates the voltage outputted from a limiter circuit A, and put the regulated voltage in middle voltage condition. This voltage in middle voltage condition is charged into a capacitor C' for delay to raise the upstream potential of the capacitor C' for delay, whereby the quantities of the current passage of the first and second transistors Q1 and Q2 are increased further to boost the voltage to be outputted from the limiter circuit A. As a result, the factors of safety of load and electronic parts used for the load can be estimated low.