TWO-LEVEL LED SECURITY LIGHT WITH MOTION SENSOR

摘要

A two-level LED security light with a motion sensor. At night, the LED is turned on for a low level illumination. When the motion sensor detects any intrusion, the LED is switched from the low level illumination to a high level illumination for a short duration time. After the short duration time, the LED security light returns to the low level illumination for saving energy. The LED security light includes a power supply unit, a light sensing control unit, a motion sensing unit, a loading and power control unit, and a lighting-emitting unit. The lighting-emitting unit includes one or a plurality of LEDs which may be turned-on or turned-off according to the sensing results from the light sensing control unit. When the motion sensing unit detects an intrusion, the illumination of the LED security light can be immediately turned on to the high level to scare away the intruder.

主权项

1. A LED lighting control module, comprising:
a power supply unit; a light sensing control unit; a motion sensing unit; a zero-crossing detection circuit; a loading and power control unit; and a phase controller;wherein the power supply unit is an AC/DC power converter to produce DC power(s) required for operating the LED lighting control module, wherein the phase controller is electrically connectable to an AC power source and to a LED lamp; wherein the loading and power control unit comprises a control circuitry in conjunction with the zero-crossing detection circuit to control a conduction period of the phase controller in each half cycle of the AC power source thereby to adjust an average power delivered to the LED lamp; wherein the phase controller is confined to operate in a time phase domain between t0 and ½f−t0 in each AC half cycle, wherein f is the frequency of the AC power source and t0 is the corresponding time phase of a minimum voltage (Vt) required to turn on the LED lamp to start emitting light, featuring an illumination characteristic of the LED lamp; wherein the LED lamp performs different illumination levels according to sensing signals received from the light sensing control unit and the motion sensing unit; wherein when an ambient light detected by the light sensing control unit is lower than a first predetermined value, the control circuitry of the loading and power control unit adjusts the average power delivered to the LED lamp to generate a low level illumination; wherein when the ambient light detected by the light sensing control unit is higher than a second predetermined value, the control circuitry of the loading and power control unit turns off the LED lamp; wherein when a motion intrusion is detected by the motion sensing unit, the control circuitry of the loading and power control unit manages to increase the average power delivered to the LED lamp and a high level illumination is thereby generated for a predetermined duration.