The TPS53318 and TPS53319 devices are high-efficiency, single channel, synchronous buck converters suitable for low output voltage point-of-load applications in computing and similar digital consumer applications. The device features proprietary D-CAP mode control combined with an adaptive on-time architecture. This combination is ideal for building modern low duty ratio, ultra-fast load step response DC-DC converters. The output voltage ranges from 0.6 V to 5.5 V. The conversion input voltage range is from 1.5 V to 22 V and the VDD bias voltage is from 4.5 V to 25 V. The D-CAP mode uses the equivalent series resistance (ESR) of the output capacitor or capacitors to sense the device current. One advantage of this control scheme is that it does not require an external phase compensation network allowing for a simple design with a low external component count. Eight preset switching frequency values can be chosen using a resistor connected from the RF pin to ground or VREG. Adaptive on-time control tracks the preset switching frequency over a wide input and output voltage range while allowing the switching frequency to increase at the step-up of the load.