The HMA121AV is a transistor output optocoupler from Fairchild/ON Semiconductor. It has a maximum forward voltage of 1.3V and can handle a continuous forward current of 50mA. The device comes in a 4-Mini-Flat package and can operate in a temperature range of -40°C to 100°C. The minimum DC current transfer ratio of the HMA121AV is 100% at 5mA, while the maximum DC current transfer ratio is 300% at 5mA. The device has an isolation voltage of 3750Vrms and can handle a maximum output voltage of 80V. The switching turn-on and turn-off time of the HMA121AV is not specified, but the rise and fall time is 3μs. The device is categorized as an isolator and is now obsolete (EOL). The supply and demand status of the HMA121AV is limited.