The H11A4 is a transistor optoisolator from Lite-On Inc. It belongs to the H11AX series of optoisolators, which are widely used in applications requiring electrical isolation. This optoisolator has a tube package and a standard package of 65 pieces. It features a transistor with base output type and DC input type. The maximum forward current (If) is 60mA, and the typical forward voltage (Vf) is 1.2V. The rise and fall time is 2.8μs and 4.5μs respectively. It has a current transfer ratio of 10% at 10mA and a maximum output voltage of 30V. The H11A4 is designed for through-hole mounting and is suitable for a wide temperature range of -55°C to 100°C. With its high isolation voltage and reliable performance, the H11A4 is an excellent choice for applications requiring optoisolation.