Exar’s XRP6161 synchronous step-down controller, which supports point-of-load (POL) supplies up to 35 A, leverages the company’s emulated current-mode constant on-time (COT) control loop to enhance transient response and output accuracy. The COT control scheme offers the fast transient response of COT control loops without any of the compromises, says Exar. It enables operation with ceramic output capacitors, eliminating loop compensation. The controller’s input voltage ranges from 4.5 to 22 V, delivering an adjustable output voltage from 0.6 to 18 V. Combining 0.1% line regulation across the entire input voltage range with 1% output accuracy over the full temperature range increases headroom to facilitate design implementations. Supervisory and protection features help ensure proper sequencing and safe operation under abnormal operating conditions. Packaging is a 3- by 3-mm QFN. The device will provide core voltage rails for ASICs, FPGAs, digital signal processors, and network processors in communications, networking, and industrial applications.