Half-bridge driver for high-current synchronous buck converters
The Vishay SIC645AER-T1-GE3 is a VRPower® half-bridge NMOS driver designed for synchronous buck converters and voltage regulators. It integrates a bootstrap circuit and status flag, and uses a PWM interface to drive inductive loads. The low-side Rds(on) is typically 0.76mΩ and the high-side is 3.6mΩ, which keeps conduction losses low in high-current rails. The device operates from a 4.5V to 18V load voltage and requires a 4.75V to 5.25V supply for the internal gate drive. Fault protection includes current limiting, over-temperature, shoot-through, and UVLO, reducing the need for external supervisory components.
Thermal and package considerations for layout
The SIC645AER-T1-GE3 is housed in a 32-PowerWFQFN package with a PowerPAK® MLP55-32 Double Cooling exposed pad. This dual-cooling footprint is designed to pull heat from both the top and bottom of the package, which matters when the part is delivering tens of amps through the low-side FET. Without that via stitch, junction temperature will rise faster than the 125°C rating allows under continuous high load. The package is surface-mount only, so reflow profile and solder paste coverage on the pad area are critical for both electrical connection and thermal performance.
It is ROHS3 compliant.