AVT1815 - 4-channel remote switch controlled by any infrared remote control
A simple remote controlled switch, that works with any infrared remote control. It has four relay outputs. Its advantage is possibility of being controlled with any remote control unit. Teach-in procedure is simple reduced to a few steps.
• Enables and disables 4 devices.
• Operated manually or via infrared remote control unit.
• Works with almost any IR remote.
• Very easy and intuitive teach-in procedure for learning the pilot codes.
• Power supply: 9-14V DC.
• PCB dimension: 83×98mm.
• Electronic Kit – soldering required.
The schematic of the remote controlled switch is shown in Figure 1. The device should be powered from any 12V external power supply with power capacity corresponding to attached load. Input voltage is applied to voltage stabilizer 7805 (U1). The IR receiver is a TSOP4836 integrated circuit. The switch functionality is implemented by the ATmega microcontroller. The main task of the microcontroller is to receive the signal from the IR receiver and to analyze the codes sent from the IR transmitter. The output is buffered by ULN2003A, which is powering output relays.
When switching on high power loads, attention should be paid to the load of the PCB tracks. To improve their load capacity, copper wire could be soldered. The switch has buttons for direct switching on and off of relays without the need for a remote control. Briefly pressing the button allows you to change the state of the relay. LED1...LED4 are indicating which relay is currently on. LED 5 informs of the operation of the device, receiving the command from the remote control and entering the programming mode.
Assembly and test
The assembly diagram is shown in Figure 2 in the user manual. The assembly starts from the soldering the resistors and other small components, and ending with the assembly of electrolytic capacitors, relays and screw terminals. The remote controlled switch assembled from the tested components does not require any adjustment and after registering the commands sent by the IR remote is ready for operation.
Entering the programming mode takes place after pressing the corresponding button for about 5 seconds. When it is done, the LED corresponding to the programmed channel will blink. This means that the switch is waiting to receive and acknowledge the command from the remote control that will be responsible for switching the corresponding relay.
Correct reception of the remote command will cause the LED to illuminate for a long time, after which the LED blinking will indicate that the switch is waiting for the confirmation of the registered command. To do this, press the same button again on the remote control. When the correct command is received, the programming procedure is completed and the switch returns to normal operation. Entering the programming mode is possible at any time during operation of the device and is carried out independently for each of the four channels.
R6 -R10: 1kΩ
C1, C6: 100µF
C7, C8: 22pF
U2: ATmega8 with 28-pin IC socket
U4: ULN2003 with 20-pin IC socket
LED1-LED5: LED diode
VCC: power connector 2.1/5.5
OUT1-OUT4: 3-pin terminal block connector