Designing the AP65550 synchronous buck converter centered on optimizing transient response in low-voltage TV and monitor applications, says Diodes Inc. According to the company, the 5-A-rated device, based on an adaptive, constant-on-time control algorithm, quickly reacts to rapid changes in load changes, guaranteeing a minimal drop in output voltage. The algorithm handles widely varying input/output voltage ratio, and enables the use of low and ultra-low equivalent-series-resistance capacitors. Its 4.5- to 18-V operating voltage range, plus SO-8EP packaging, suits it for 5-, 9-, and 12-V bus systems. An automatic light-load, efficiency-improvement feature promotes seamless transition between continuous conduction mode at higher loads, and discontinuous conduction mode at lighter loads. Protection features include undervoltage lockout, thermal shutdown, overcurrent, and programmable soft-start.