4.5-V to 17-V, 6-A synchronous SWIFT™ buck converter with hiccup current limit

The TPS54622 device in thermally enhanced 3.5-mm × 3.5-mm VQFN package is a full-featured 17-V, 6-A synchronous step-down converter optimized for small designs through high efficiency and integrating the high-side and low-side MOSFETs. Further space savings are achieved through current mode control, which reduces component count, and by selecting a high switching frequency, reducing the footprint of the inductor.

The output voltage start-up ramp is controlled by the SS/TR pin, which allows operation as either a stand-alone power supply or in tracking situations. Power sequencing is also possible by correctly configuring the enable and the open-drain power good pins.

Cycle-by-cycle current limiting on the high-side FET protects the device in overload situations and is enhanced by a low-side sourcing current limit that prevents current runaway. There is also a low-side sinking current limit that turns off the low-side MOSFET to prevent excessive reverse current. Hiccup protection is triggered if the overcurrent condition has persisted for longer than the preset time. Thermal hiccup protection disables the device when the die temperature exceeds the thermal shutdown temperature and enables the part again after the built-in thermal shutdown hiccup time.