Schottky rectifier for low-voltage rail protection
The STMicroelectronics BAT48JFILM is a Schottky diode rated for 40 V reverse voltage and 350 mA average forward current, housed in a SOD-323 surface-mount package. It is designed for low-voltage rectification, freewheeling, and polarity-protection circuits where the forward voltage drop directly impacts efficiency.
Forward drop and switching speed
Maximum forward voltage is 750 mV at 200 mA, which sets the conduction-loss floor for a 350 mA-rated part. The fast-recovery characteristic — ≤ 500 ns above 200 mA — means it can handle moderate switching frequencies without excessive reverse-recovery losses, suitable for DC-DC converter output rectification and flyback catch diodes.
Reverse leakage and capacitance
Reverse leakage is 25 µA at 40 V, and junction capacitance is 30 pF at 0 V, 1 MHz. The low capacitance keeps switching losses down in high-frequency paths, while the leakage at rated reverse voltage is typical for a 40 V Schottky in this current class.