Patent ID: 8922125
Filing Date: 2014-12-30
Classification: H05B,Y02B

Abstract:
1. An occupancy sensor for electrically connected between an LED driver and an LED module, said occupancy sensor comprising: an occupancy sensing module with capability of sensing occupancy status of a specific area and producing a signal while an object is entering the specific area; a main control module with capability of processing the signal from the occupancy sensing module and controlling; a current control module electrically connected to the main control module with capability of regulating a driving current output for the LED module, said current control module comprising: a current regulator, a power switch, a current sensor and a current controller all electrically connected to control the driving current output for the LED module; wherein the current controller multiplies a maximum current value by a brightness ratio from the main control module to obtain a reference current for controlling the power switch, increases a duty cycle of the power switch when the current through the LED module is smaller than the reference current, and reduces the duty cycle of the power switch when the current through the LED module is larger than the reference current.