7.8 mOhm high-side switch for 4 A rails
The SLG59M309V is a single-channel, high-side load switch from Renesas, built with an N-Channel MOSFET that delivers a typical on-resistance of 7.8 mOhm. At 4 A continuous output, that Rds(on) produces about 125 mW of conduction loss — well within the thermal budget of the 8-FC-TDFN (1.5x2) package when the exposed pad is soldered to a proper copper land on the PCB. For a factory-floor sensor node or a telecom line card running at 70°C internal ambient, this part has margin.
Package, footprint, and reflow considerations
The SLG59M309V comes in an 8-FC-TDFN (1.5x2) package, also called the 8-FC-TDFN (1.5x2) supplier package. It is offered in Tape & Reel (TR) and Cut Tape (CT) options. The reel format feeds directly into a pick-and-place line for volume production; the cut tape suits prototype builds and small-batch runs without committing to a full reel quantity. Surface-mount assembly is straightforward — the 1.5x2 mm footprint is small but not exotic, and the package coplanarity is standard for a TDFN. No special reflow profile beyond the solder paste manufacturer's recommendation for lead-free is needed.
Active lifecycle and compliance
For a BOM line that requires a high-side load switch with under 8 mOhm Rds(on) and a 4 A continuous rating, this part is a current-design fit — no last-time-buy planning or obsolescence risk to manage.