Dual 600 mA rail in a 3x3 QFN
The LTC3607IUD#TRPBF is a dual-output step-down buck regulator from Analog Devices, delivering 600 mA per channel from a 4.5 V to 15 V input rail. It integrates synchronous rectifiers on both channels, so the efficiency curve stays competitive without external Schottky diodes — the internal low-side FET carries the recirculating current and the dead-time is handled by the controller.
Switching at 2.25 MHz shrinks the magnetics
The 2.25 MHz switching frequency lets the designer use a small-value inductor — typically 1 to 2.2 µH per channel — which fits the 16-QFN (3x3 mm) footprint into a tight PCB area. The trade-off is switching loss in the FETs; at this frequency the efficiency peak sits around the 100-300 mA load per channel, not at full 600 mA. The adjustable output starts at 0.6 V, so it can power a 1.2 V or 1.8 V core rail directly from a 5 V or 12 V bus.
Industrial temperature grade and package reality
Rated for -40°C to 125°C junction temperature, the LTC3607IUD#TRPBF suits equipment that sees under-hood or factory-floor ambient — a motor drive enclosure hitting 85°C internal still leaves margin before the 125°C ceiling. The 16-WFQFN with exposed pad (3x3 mm) requires a thermal via pattern under the pad to pull heat into the inner ground plane; without it the junction temperature rises faster than the derating curve predicts.