PCB 시리즈 13편 / 옵토커플러와 절연회로

📌 PCB Series Part 13 | Principles of Optocouplers and Isolation Circuits, and Practical Inspection Methods An optocoupler is a core component that transmits signals via light while completely electrically isolating high-voltage circuits from low-voltage control circuits. It is used in most electronic products, such as air conditioners, washing machines, dryers, SMPS, and inverter PCBs, for MCU protection, isolation, noise blocking, and feedback control. In this video, we provide an easy-to-understand explanation of the structure and operating principles of optocouplers, the role of isolation circuits, SMPS feedback circuits, actual failure symptoms, and inspection methods. --- 🔧 Key Contents Structure and operating principles of optocouplers Reasons why isolation circuits are necessary Roles of LEDs and phototransistors Principles of signal transmission using light Isolation of high-voltage and low-voltage circuits MCU protection and safety circuits Operation of SMPS feedback circuits Interoperability with PWM control ICs Applications in inverter PCBs Configuration of air conditioner PCB isolation circuits Noise blocking and surge protection Isolation techniques for preventing electric shock Symptoms of optocoupler failure How to check input LEDs How to check output phototransistors How to measure diodes Verification of signals using an oscilloscope Checking TL431 and feedback circuits Checking surrounding resistors and capacitors Precautions when replacing parts Checking pin orientation and isolation distance Practical PCB fault diagnosis tips --- 🛠️ Key Inspection Points Checking for external discoloration and cracks Checking for input LED open circuits and short circuits Verifying the normality of output signals TL431 Operation Verification Measure feedback circuit voltage Check for abnormalities in surrounding resistors and capacitors Check for cold solder joints and pattern damage Check insulation distance and soldering condition --- 🎯 Recommended for: Those learning PCB repair Those studying air conditioner PCBs Those studying washing machine PCBs Those who want to understand SMPS principles Those learning electronic circuits for the first time Those interested in DIY home appliance repair Those preparing for a technology-based startup --- 🔊 *This video includes YouTube Auto Dubbing in multiple languages.* #PCB #Optocoupler #InsulationCircuit #SMPS #FeedbackCircuit #AirConditionerPCB #WashingMachinePCB #ElectronicCircuit #PCBRepair #CircuitRepair #ElectronicsBasics #OldMechanic #Optocoupler #Electronics