Switching Diodes
General-purpose fast-recovery signal diodes for steering, clamping, and small-signal rectification.
What is it?
Switching diodes (also called signal diodes or general-purpose diodes) are low-power diodes optimised for fast switching speed and low forward voltage drop. The classic part is 1N4148; common SMD parts include BAS16 and the dual BAV99, BAW56 and BAV70. Small-signal Schottky types such as BAS40 and BAS70 do a similar job with a lower forward drop. Used wherever you need a one-way path for small currents, typically up to a few hundred milliamps.
When do you need it?
- Signal-level rectification (peak detectors, demodulators).
- Diode-OR logic gating multiple sources to one rail.
- Clamping flyback voltage on low-current relays or solenoids.
- Voltage-level shifting via diode drops.
- Reverse-polarity protection on low-current inputs.
How to pick the right one
- Forward current (IF)
- Choose at least 2× your continuous current. Common ratings are 150-250 mA (BAV99 family 150-200 mA, BAW56 250 mA).
- Reverse voltage (VR)
- Higher than the maximum reverse voltage in your circuit. 70 V / 100 V / 200 V common.
- Forward voltage (VF)
- Standard silicon ~0.7 V, Schottky variants ~0.3-0.4 V. Schottky saves power but has higher reverse leakage.
- Reverse recovery time (Trr)
- Critical for >10 MHz switching. Fast switching diodes have Trr < 10 ns.
- Configuration
- Single (SOD123-2L, SOD323, SOD523, DFN1006-2L, DFN0603-2L) or dual: series (BAV99), common-anode (BAW56) or common-cathode (BAV70) in SOT23 and SOT323, and BAV99DW with two pairs in SOT363.
What Magnias offers
Magnias switching diodes include the 1N4148W family, BAS16, BAS316WX and BAS516, the dual BAV99, BAW56 and BAV70 families in SOT23, SOT323 and SOT363, 100-250 V parts (BAV19WX to BAV21WX, BAS21), low-leakage BAS416WX and BAV199EL, and 1SS400C-F2 in DFN0603-2L. AEC-Q101 versions are available for many parts (see each datasheet). Small-signal Schottky diodes (BAS40, BAS70, BAT54) are on the Schottky page.