600 V small-signal MOSFET in SOT-223
The Infineon BSP125H6327XTSA1 is an N-channel enhancement-mode MOSFET from the SIPMOS® family, rated for 600 V drain-source voltage and 120 mA continuous drain current. It comes in a PG-SOT223-4 surface-mount package with a tab for heat sinking. The 45 Ohm maximum on-resistance at 10 V gate drive and 120 mA load is typical for a high-voltage small-signal MOSFET — this part is not a main power switch but a bias-supply, auxiliary-converter, or pre-regulator device. The wide junction temperature range from -55°C to 150°C qualifies it for industrial, automotive under-hood, and outdoor telecom environments where thermal cycling is severe.
Gate drive and switching characteristics
Gate threshold voltage maximum is 2.3 V at 94 µA drain current. Drive voltage range is 4.5 V to 10 V for best Rds(on).
Package, mounting, and thermal notes
The PG-SOT223-4 package is a standard surface-mount footprint with a large drain tab. Maximum power dissipation is 1.8 W at 25°C ambient, derated above that. For continuous operation near 120 mA drain current at high drain voltage, the tab should be soldered to a copper plane on the PCB to keep junction temperature within limits. The part is supplied in Tape & Reel (TR) or Cut Tape (CT) options, compatible with automated pick-and-place assembly.
Lifecycle and compliance
Infineon lists the BSP125H6327XTSA1 as Active — no end-of-life notice, no last-time-buy window. It is ROHS3 compliant, with no halogen or lead restrictions that would block use in EU or North American markets. The SIPMOS® series is a mature high-voltage MOSFET platform; second-source options from other manufacturers exist in the same SOT-223 footprint, but Infineon is the primary source for this specific order code.