The MAX8543/MAX8544 can start with (or without) a preexisting bias on the output, without discharging the output. This feature simplifies tracking supply designs for core and I/O applications and redundant supply designs. The MAX8543/MAX8544 use the DC resistance of the output inductor as the current-sense element for lossless, low-cost current sensing. The current-sense threshold can be set to four discrete levels to accommodate inductors with different DC resistance values. The MAX8544 features a power-OK monitor and two MAX8544 controllers that can operate at 180 out-ofphase for dual-output applications.