The RT6219A is a synchronous Buck converter with Advanced Constant On-Time (ACOTTM) mode control which provides a very fast transient response with no external compensators. The RT6219A operates from 5V to 23V input voltage, provides complete protection functions including Over Current Protection (OCP), Under Voltage Protection (UVP) and Over Voltage Protection (OVP). This IC also provides a 1.5ms internal soft-start function and an open-drain power good indicator.