Home automation presupposes the presence of motion sensors that are capable of monitoring human movements. The simplest and most affordable device for monitoring changes in infrared radiation is PIR sensors. At the moment, not expensive models D203B, D204B, D205B are available. All of them allow the manufacture of inexpensive and simple devices for controlling human movement. These sensors are manufactured in metal housings. Sensors mainly differ in sensitivity, but structurally in the size of the light-sensitive window.
A compact sensor was designed to directly control low-voltage loads from 12 to 24 volts and load current up to 3 Amperes (the current depends on the MOS key).
The logic of the sensor is assigned to the PIC -controller, PIC10F222 is selected as the controller. The board can accommodate two MOS switches, which directly allow you to connect low-voltage loads up to 3 Amperes. The installation of an LED indicator is provided for monitoring the operation of the sensor. And also a connector for in-circuit programming of the controller.
The project under consideration is intended to create motion sensors that control lighting directly with a load on LED strips. Such sensors can be installed in cabinets, on bookshelves, table lighting, if there is a person in the sensor control zone, it will automatically turn on the light.
The circuit is a conventional amplifier based on two op amps. Their task is to amplify the variable component from the PIR sensor. Then the signal goes to the input of the ADC of the PIC controller, the function of which is the logical processing of the signal. MOS switches are connected to the peak controller, their power load control function. It is supposed to use LED strips with a current of up to 3A as a load. In this constructor, only one field-effect transistor is used, depending on the desired operating mode, it is soldered in place of V1 or V2. The transistors operate in antiphase, as follows, in normal mode V1 is open and the OUT1 output is pulled to minus. When the motion sensor is triggered, V1 closes and V2 opens, the OUT2 output is pulled to minus. Delay after triggering approx. 20 seconds, if during this time motion detection was not detected, then the sensor switches to security mode.
There is also a place on the printed circuit board for installing a downward linear stabilizer
MCP1804T or
RT9058-50GV, which will increase the supply voltage range. In this case, the circuit will need to be powered through the CON2 connector, the 4th and 5th pins.
Kit Contents
1. Printed circuit board
ch-c0060 -1pc.
2. Microcontroller PIC10F222 with firmware -1pc.
3. PIR sensor
D203S -1pcs.
4. Sensor lens
HW-8120 -1pc.
5. Operational amplifier
MCP601T -2pcs.
6. Transistor
AO3404A -1pc.
7. Condenser
0805 100nf (0.1uf) -5pcs.
8. Condenser
1206 10uf -3pcs.
9. LED
¦
¦
0805 red -1pcs.
10. Resistor
0805 100K -1pc.
11. Resistor
0805 10K -6pcs.
12. Resistor
0805 1M -2pcs.
13. Resistor
0805 470R -2pcs.
14. Resistor
0805 1K -1pc.
If it is necessary to use a linear stabilizer, it must be purchased separately and all the necessary components for its installation.
Файл с описанием
The data presented in the product description are for reference only and may differ from those indicated by the manufacturer.
