Security Circuit. - This is one of implementation of microcontroller to buld security system that very useful advance world security system is in high end so the security breakers are. The main microcontroller used in this circuit is 8051 that very popular in electronic design.
The electronic design circuit of microcontroller based on security system is look like in Figure 1 below. Other component used like resistors, capacitors, transformer, relay, diodes, transistor, NE555 IC and also other component that you can look in components part below.
The electronic design circuit of microcontroller based on security system is look like in Figure 1 below. Other component used like resistors, capacitors, transformer, relay, diodes, transistor, NE555 IC and also other component that you can look in components part below.
Beside we will show you electronic design circuit and component parts need, we also will give you global description about this circuit. So, please enjoy to continue reading this article until finish and get more useful.
Electronic Circuit Design
Component Parts
- R1, R2 = 5.6 KΩ
- R3, R16, R18 – R22, R25 = 4.7 KΩ
- R4 = 100 Ω
- R5 = 3.9 KΩ
- R6, R8, R12, R15, R17 = 1 KΩ
- R7, R10, R11, R13, R14 = 10 KΩ
- R9 = 100 KΩ
- R23 = 120 Ω
- R24 = 470 Ω
- VR1 = 47 KΩ
- VR2 = 10 KΩ
- C1 = 3.3 nF ceramic disc
- C2, C6, C13, C14 = 0.1 µF ceramic disc
- C3, C8 = 0.01 µF ceramic disc
- C4 = 1 nF ceramic disc
- C5 = 10 µF, 25V electrolyte
- C7 = 2.2 µF, 25V electrolyte
- C9 = 10 µF, 10V electrolyte
- C10, C11 = 10 pF ceramic disc
- C12 = 1000 µF, 50V electrolyte
- IC1 = NE555 (timer IC)
- IC2 = µA741 (operational amplifier)
- IC3 = LM567 (Phase-Locked-loop)
- IC4 = 8085 (Microprocessor)
- IC5 = 2732A (EPROM 4k)
- IC6 = 64LS373 (Octal Transparent Latch)
- IC7 = 8255 (programmable peripheral interface)
- IC8, IC9 = MCT2E optocoupler
- IC10 = 74LS00 (NAND gate)
- IC11 = 7809 (9V regulator)
- IC12 = 7812 (12V regulator)
- T1, T3 – T9 = BC548 (NPN transistor)
- T2 = L14G1 (Phototransistor)
- D1 = 1N4148 (Switching diode)
- D2 – D10 = 1N4007 (rectifier diode)
- LED1 – LED3 = Red LED
- IR LED1 = Infrared Led
- X1 = 230V/50 Hz or 110V/60 Hz AC primary to 12V-0-12V, 300 mA secondary transformer
- XTAL = 3.5 MHz crystal
- SW1 = Push-to-on switch
- SW2 = On Off switch
- RL1, RL2, RL4, RL5 = 12V, 200 Ω, 1C/O relay
- RL3 = 12V, 200 Ω, 2C/O relay
Description
The electronic circuit design like in Figure 1 above show you microcontroller based security system. Other component need also that can supply with low voltage DC +5V source to charge this transistor and all system component from power supply built. With this electronic design circuit you can produce security system that useful now.
According ElectronicsProject blog mentioned that the transmitter section is designed and fabricate around timer IC NE555 wired as astable multivibrator followed by transistor T1 and IR LED. The oscillated frequency of transmitter section is decided by resistor R1 and R2, preset VR1 with capacitor C1. The output from pin 3 of IC1 is given to base of transistor T1 through resistor R3 for amplification as per required and given to IR LED. The modulated IR signal is transmitted by IR LED1.
The IR transmitted signal is focused on the base of photo transistor. The output from photo transistor is given to transistor T3 followed by op-amp (IC2) for amplification. The amplified signal from IC3 is given to input pin 3 of Phase-Locked-Loop (PLL) IC LM567 (IC3) through capacitor C4. The normal use of PLL IC (IC3) is frequency decoder so is here in order to drive the load. The tuning frequency is determined by variable resistor VR2 and current controlled oscillator by resistor R12. The tuning frequency (6-10 KHz) should match with modulating frequency transmitted by transmitter. Pin 8 of IC3 is connected to base of transistor T4 through resistor R13. Glowing LED1 indicate receiving signal is locked to transmitting signal. Transistor T5 is used as relay driver in order to energize the relay RL5. Relay RL1 energized normally when transmitted IR signal falls on phototransistor T2, at this time microprocessor does not get any input. But when IR signal is interrupted microprocessor get high (TTL-level) signal through port A of Programmable Peripheral Interface (PPI).
The IR transmitted signal is focused on the base of photo transistor. The output from photo transistor is given to transistor T3 followed by op-amp (IC2) for amplification. The amplified signal from IC3 is given to input pin 3 of Phase-Locked-Loop (PLL) IC LM567 (IC3) through capacitor C4. The normal use of PLL IC (IC3) is frequency decoder so is here in order to drive the load. The tuning frequency is determined by variable resistor VR2 and current controlled oscillator by resistor R12. The tuning frequency (6-10 KHz) should match with modulating frequency transmitted by transmitter. Pin 8 of IC3 is connected to base of transistor T4 through resistor R13. Glowing LED1 indicate receiving signal is locked to transmitting signal. Transistor T5 is used as relay driver in order to energize the relay RL5. Relay RL1 energized normally when transmitted IR signal falls on phototransistor T2, at this time microprocessor does not get any input. But when IR signal is interrupted microprocessor get high (TTL-level) signal through port A of Programmable Peripheral Interface (PPI).
