The TPS23882B supports 1- and 3-bit shutdown priority, which are selected with the MbitPrty bit of General Mask register (0x17).

The 1-bit shutdown priority works with the Port Power Priority (0x15) register. An OSSn bit with a value of 1 indicates that the corresponding port is treated as low priority, while a value of 0 corresponds to a high priority. As soon as the OSS input goes high, the low-priority ports are turned off.

The 3-bit shutdown priority works with the Multi Bit Power Priority (0x27/28) register, which holds the priority settings. A port with “000” code in this register has highest priority. Port priority reduces as the 3-bit value increases, with up to 8 priority levels. See Figure 9-1.

The multi bit port priority implementation is defined as the following:

• OSS code ≤ Priority setting (0x27/28 register): Port is disabled
• OSS code > Priority setting (0x27/28 register): Port remains active

Figure 9-1 Multi Bit Priority Port Shutdown if Lower-Priority Port