Figure 8-1 shows a Schottky diode between the phase node pin (PH) and GND of the TPS7H4002-SEP. This external diode is in parallel with the internal low-side power FET of the device and typically has superior reverse recovery characteristics when compared to the body diode of the internal low-side FET. This improved reverse recovery provides two key benefits. The first benefit is an better overall efficiency for the converter due to lower losses associated with the diode reverse recovery. The second key advantage is that the parasitic-induced noise associated with the reverse recovery current pulse (as detailed in Figure 5 of Power Loss Calculation With Common Source Inductance Consideration for Synchronous Buck Converters) is drastically reduced. In the absence of the Schottky diode, this noise can manifest itself on the power ground plane internal to the TPS7H4002-SEP. If significant enough, the noise can reduce the dynamic range of the error amplifier and result in higher output voltage ripple. For this reason, it is highly recommended to use the external Schottky diode in the converter design. At the least, a PCB footprint for the diode should be included in the PCB design phase in case it is needed to achieve the system requirements.