Dual P-Channel load switch for 20 V rails
The Infineon BSO211P is a dual P-Channel enhancement-mode MOSFET from the OptiMOS series, housed in a PG-DSO-8 package. It is designed for high-side load switching and power distribution in systems where a single device must disconnect or regulate two independent loads. With a continuous drain current rating of 4.7 A at 25°C and a maximum on-resistance of 67 mOhm at Vgs = 4.5 V, each channel can handle moderate loads while keeping conduction losses under control.
On-resistance and gate charge — sizing the drive and the thermal budget
The 67 mOhm Rds(on) at 4.5 V is the figure to use for worst-case conduction loss at the rated current. At 4.7 A, that is about 1.48 W per channel, which exceeds the 2 W package power limit if both channels run at full current simultaneously — so derating or pulsed operation is required when both channels are active. Total gate charge is 23.9 nC at 4.5 V. For a 100 kHz switching frequency, the average gate-drive current per channel is about 2.4 mA, well within the capability of a standard logic output or a small dedicated gate-driver IC. Input capacitance (Ciss) of 920 pF at Vds = 15 V is moderate; the switching speed is limited more by the gate-drive source impedance than by the device itself.
RoHS compliance — a flag for lead-free assembly lines
The BSO211P is listed as RoHS non-compliant, meaning the terminations contain lead (typically solder-dipped or tin-lead plating). This is a hard constraint for designs that must meet RoHS exemption limits; it also affects the reflow profile if the board is assembled in a mixed-technology line.