DO-213AA MELF — board-fit and reflow considerations
The 1N645-1/TR ships in a DO-213AA MELF (Metal Electrode Leadless Face) package — a cylindrical body with metallized end caps that replace traditional leads. The MELF footprint demands a well-defined solder-paste stencil aperture: too little paste and the end-cap wets unevenly, too much and the part tombstone during reflow. Pad geometry follows the package outline; the recommended land pattern is available in the Microchip application note for MELF devices. Tape & Reel packaging means the diode feeds directly into a pick-and-place machine — no tube changeover or tray handling. The hermetic glass-body MELF construction has no moisture sensitivity level (MSL) concern, so no bake-out is required before reflow even after extended storage.
400 mA, 225 V — what the rectifier ratings mean for your rail
Rated 400 mA average rectified current (Io) at 225 V DC reverse voltage (Vr). The 1 V forward drop at 400 mA sets the conduction loss at 400 mW — well within the DO-213AA's thermal budget at 25°C ambient, but derating is needed above 100°C junction. The 50 nA max reverse leakage at 225 V is low for a 225 V part, making this diode suitable for high-impedance bias networks and low-power standby rails where leakage current would otherwise drain the reservoir capacitor. Use it for 50/60 Hz line rectification, DC blocking, polarity protection, and snubbing where recovery speed is not a constraint.
Active lifecycle — sourcing posture
The Tape & Reel quantity is the standard production reel; no minimum-order-surplus risk on this line.