On-resistance and gate drive — what they mean for your design
The maximum on-resistance is 175 mOhm at a gate-source voltage of 4.5 V and a drain current of 500 mA. The maximum gate threshold voltage is 1.2 V at 250 µA. Gate charge is 1.14 nC at 6 V, so switching losses are negligible at moderate frequencies — this part is not intended for high-speed power conversion but for DC load switching where the gate is driven at low kHz rates or simply held on.
Sourcing and lifecycle — active, no LTB risk
The CSD23381F4T is listed as Active by Texas Instruments, with ROHS3 compliance. No official second source or pin-compatible replacement is listed, so dual-sourcing would require a separate qualification of a similar-footprint P-channel FET.
