New AP65500 and AP65400 synchronous dc-dc buck converters from Diodes Inc. feature continuous load current of 5 A and 4 A, respectively (7 A peak), at an efficiency as high as 96%. Operating at a switching frequency of 340 kHz, the devices incorporate a light-load efficiency improvement algorithm to maintain low-loss performance across a wide load range. Current-mode control is designed in for point-of-load power management. Among other features are enhanced line and load regulation, and fast response to transient load. Operating voltage ranges from 4.75 to 18 V, which means the converters can support 5-, 9-, and 12-V bus systems. Output is adjustable from 0.8 to 16 V. Built-in protection includes current limit, overvoltage, undervoltage lockout, and thermal shutdown. A programmable soft-start function prevent excessive in-rush current and output-voltage overshoot. The converters, integrating low on-resistance high- and low-side MOSFETs and housed in compact SO-8EP packages, help minimize space requirements for distributed power architectures.