The TPS51117 is a cost effective, synchronous buck controller for POL voltage regulation in notebook PC applications. The controller is dedicated for Adaptive On-Time D-CAP Mode operation that provides ease of use, low external component count, and fast transient response. Auto-skip mode for high efficiency down to the milli-ampere load range, or PWM-only mode for low noise operation is selectable.

The current sensing scheme for positive overcurrent and negative overcurrent protection is loss-less low-side R_DS(on) sensing plus temperature compensation. The device receives a 5-V (4.5 V to 5.5 V) supply from another regulator such as the TPS51120 or TPS51020. The conversion input can be either VBAT or a 5-V rail, ranging from 1.