AC/DC input optocoupler — the input that catches both halves of the mains cycle
The onsemi H11AA1SVM is a single-channel optocoupler whose input stage accepts both AC and DC drive. That means the LED conducts on both the positive and negative half-cycles of an AC waveform — a single part handles zero-crossing detection, AC line monitoring, or bidirectional signal isolation without needing a bridge rectifier ahead of the input. Rated for 4170Vrms isolation, this part provides reinforced galvanic separation between the AC-side input and the 30V-rated transistor output. The 20% minimum current transfer ratio at 10mA forward current means the output transistor saturates with 2mA collector current when the LED is driven at 10mA — enough to drive a logic input or a low-current relay coil.
Surface-mount 6-SMD Gull Wing — board integration note
Packaged in a 6-SMD Gull Wing outline with a 6-SMD supplier device package designation, the H11AA1SVM mounts flat to the board surface — no through-hole leads, no secondary soldering step. The Gull Wing leads provide visual solder-joint inspection access and self-centering during reflow.
Temperature grade and output drive capability
The 50mA continuous output current per channel with a 60mA absolute-maximum DC forward current gives margin for driving small solenoids, indicator LEDs, or PLC input modules. The 1.17V typical forward voltage at rated drive current means the input LED drops roughly the same voltage regardless of AC or DC polarity — a series resistor sized for the peak AC voltage sets the peak current, and the average current determines the CTR operating point.
