Patent ID: 6147460
Filing Date: 2000-11-14
Classification: H05B

Abstract:
A flash apparatus comprising:a transformer;a switching element connected in series to a primary coil of said transformer, said switching element being turned on to cause a current from a power supply to flow to the primary coil and being turned off to cut off the current to the primary coil;current-to-voltage conversion means connected to a secondary coil of said transformer for forming a voltage according to a value of a current flowing to the secondary coil; anda signal forming circuit which detects the voltage formed by said current-to-voltage conversion means and shifts an output state thereof from a first signal output state to a second signal output state when having detected that the voltage indicates a voltage value representing that the value of the current flowing to the secondary coil is less than a predetermined value,wherein said switching element is connected to said signal forming circuit and is arranged to be turned on when the output state of said signal forming circuit is the first signal output state and to be turned off when the output state of said signal forming circuit is the second signal output state.