This is a design circuit for
security light and switch circuit using PIR Sensor. SB0061
is a pyroelectric sensor module,developed for human body detection. A PIR
detector combined with a fresnel lens are mounted on a compact size PCB
together with an analog IC (SB0061) and limited components to form the module.
High level output (3.3V) of pre-settable variable width (5Secs -18 Minutes) is
provided. This is the figure of the circuit;
Circuit diagram of the PIR
Motion Sensor Light and Switch based on SB0061 shown here can be used for
security or corridor lighting in power saving mode. The 12V DC supply required
for the whole circuit can be fed from any standard 12V ac mains
adaptor/battery.
Working of the circuit is
simple and straight forward. When any movement is detected within near 5-6
metres, around 3.3 Volt is appeared at the base of Transistor T1 and it
conducts to fire the next relay driver transistor T2. As a result, the 12V DPDT
relay is energised to power the White LED through current limiting resistor R3.
Spare relay contacts can be used as a switch to control any suitable external
load. The white LED and the relay remains ON for a duration based on the mono
time setting in SB0061, ie from 5 Secs to 18 Minutes.
