Low-side switch with 20 mOhm on-resistance
The Infineon IPS1021RTRRPBF is a single-channel low-side N-channel power switch in a D-Pak (TO-252-3) package. The input is non-inverting with a simple On/Off interface — no Vcc supply is required, so the gate drive comes directly from the logic signal.
4.3 A output and 150°C junction rating
Rated for continuous output current up to 4.3 A, the IPS1021RTRRPBF is sized for solenoid, relay, lamp, and general-purpose inductive or resistive loads in the 2–4 A range. The 20 mOhm typical Rds(on) at 25°C means I²R losses at 4 A are roughly 0.32 W — the D-Pak copper pad area on the PCB must be sized to keep the junction below the 150°C ceiling.
Integrated fault protection reduces external circuitry
The switch includes fixed current limiting and over-temperature protection, so it handles short-circuit and thermal overload without an external sense resistor or fuse. The 1:1 input-to-output ratio means one logic signal controls one load channel. Fault protection kicks in autonomously — the switch latches off or cycles depending on the fault condition, protecting the load and the PCB trace.
Obsolete — sourced through surplus and broker channels
Infineon lists the IPS1021RTRRPBF as Obsolete. No pin-compatible second source is documented in the available records.