SLVSFP1 August 2021 TPS25868-Q1 , TPS25869-Q1
PRODUCTION DATA
The TPS2586x-Q1 has two USB ports. Since the secondary current limit, IOS_HI, is 1.6x of the primary current limit, IOS_BUS, if the two USB ports pull out larger current at the same time, then the DC-DC regulator is overloaded, and DC-DC regulator output voltage can be crashed. To avoid these potential issues, the TPS2586x-Q1 adopts the interlocking scheme to manage the current limits of the two USB ports.
For interlocking, if one USB port current is beyond the primary current limit threshold, IOS_BUS, then another USB port current limit threshold will be overridden to the primary current limit, IOS_BUS, immediately. With this control scheme, the TPS2586x-Q1 only allows one USB port to output a large current, which can as high as 1.6x of the primary current limit, IOS_BUS, at the same time. Ensure the DC-DC regulator has enough energy to sustain its output voltage.