40 V Schottky in a common-cathode pair — what it buys you
The Infineon BAS40-05E6327 is a dual Schottky diode in a common-cathode configuration, housed in a standard SOT-23-3 surface-mount package. This part is designed for small-signal switching and protection roles — think OR-ing diodes, steering diodes, or low-current rectification in power management and signal conditioning circuits. The 150°C junction temperature rating gives it headroom for warm environments like a PSU or a motor drive board.
120 mA per diode — sizing the load budget
Each diode in the pair handles 120 mA DC continuous. That is the number to check against your worst-case load — if your circuit pulls 100 mA through one leg, you have 20 mA of margin. The forward drop of 1 V at 40 mA gives you a rough power dissipation estimate: at 100 mA the drop will be higher, so budget the junction temperature rise against the 150°C max. For a typical 5 V rail OR-ing application, this part works cleanly; for a 12 V rail with higher current, you would want a larger Schottky.
Common-cathode topology — the wiring decision
The 1 Pair Common Cathode arrangement means the cathodes of both diodes are tied together internally, with the two anodes brought out separately. That is the footprint for a dual-diode OR-ing circuit or a voltage-clamp pair. If your board expects a series pair or a common-anode configuration, this is not the part — look at the BAS40-06 (common anode) or BAS40-04 (series pair) instead.
No need to stockpile or hunt for a second source yet.