30 V, 100 mA N-channel — signal-level load switch
The Toshiba SSM3K15ACTC,L3F is a small-signal N-channel MOSFET from the U-MOSIII series, rated for 30 V drain-to-source and 100 mA continuous drain current at 25 °C ambient. It is built for low-current load switching, level translation, and signal gating where board area is tight.
On-resistance and gate drive — 3.6 Ohm at 4 V
Maximum on-resistance is 3.6 Ohm at 10 mA drain current with a 4 V gate drive. The drive voltage range for minimum Rds(on) is 2.5 V to 4 V, meaning a 3.3 V logic GPIO can turn the MOSFET fully on without a level shifter. Input capacitance is only 13.5 pF at 3 V drain-source, so the gate charge per cycle is negligible. A microcontroller GPIO can drive the gate directly at moderate switching frequencies without an external driver.
Package and footprint — SC-101 / SOT-883 (CST3C)
This is a very small surface-mount package — the PCB footprint and solder-paste stencil aperture must be designed for the 0.50 mm pitch and small pad geometry typical of this case. Maximum power dissipation is 500 mW at 25 °C ambient, derated for higher temperatures. The junction temperature rating is 150 °C, consistent with the small package's thermal limits.
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