Exar leveraged its emulated current-mode Constant On-Time (COT) control loop to boost transient response and output accuracy in the XR761xx PowerBlox family of synchronous step-down dc-dc regulators. The COT control loop enables operation with ceramic output capacitors, eliminating loop compensation. The XR76108, XR76112, and XR76115 support point-of-load (PoL) supplies of 8, 12, and 15 A, respectively. Input voltage for the family ranges from 4.5 to 22 V; adjustable output voltage ranges from 0.6 to 18 V. Line regulation of 0.1% across the entire input voltage range and 1% output accuracy over the full temperature range helps increase headroom. With a selectable power-saving mode, users can operate in discontinuous mode at light current loads. Protection features include overcurrent, overtemperature, short-circuit, and UVLO. The XR76108 and XR76112 come in 30-pin, 5-by-5 QFN packages, while the XR76115 comes in a 30-pin, 6-by-6 QFN. Applications include ASICs, FPGAs, DSPs, and network processors in the communications, networking, and industrial arenas.