Patent ID: 7123136
Filing Date: 2006-10-17
Classification: G01R,H05B

Abstract:
1. An indicator system comprising: an light emitting diode indicator having a plurality of electrically connected lines of light emitting diodes that emit light when power is supplied, wherein the lines are arranged in parallel to each other; a flashing switch for turning on and off power supply from a power source to the light emitting diode indicator; a flashing control circuit for controlling open and closure of the flashing switch after the light emitting diode indicator is turned on through an operation of an indicator switch; an open-circuit detecting circuit for detecting an open circuit in at least one of the lines of light emitting diodes through a comparison between a threshold voltage and an indicator voltage converted from current flowing from the power source to the light emitting diode indicator; and a low-voltage filtering circuit for filtering out results of the comparison if a power source voltage is smaller than a predetermined level.