NCP1090, NCP1091, NCP1092 Integrated IEEE 802.3af PoE-PD Interface Controller Description The NCP1090, NCP1091 and NCP1092 are members of NCP1090, NCP1091, NCP1092 VPORTP DETECTION INTERNAL THERMAL SUPPLY SHUTDOWN & VOLTAGE REFERENCE DET UVLO EXTERNAL UVLO SELECTION NCP1091 only VPORT CLASS CLASSIFICATION MONITOR IEEE Interface Shutdown AUX (AUX supply priority) NCP1092 only HOT SWAP SWITCH PGOOD POWER GOOD INRUSH & CONTROL & CURRENT INRUSH OPERATIONAL INDICATOR CURRENT LIMIT LIMIT BLOCKS VPORTN RTN Figure 1. NCP1090/91/92 Functional Block Diagram