The TPS22986 is a supply selection device for active Thunderbolt™ cables. The device selects a 3.3V input from two available supplies and connects the chosen input to two outputs, OUTA and OUTB. When a 3.3V supply is not present, the outputs become high impedance.
The TPS22986 has two modes of operation, Normal and Control. In Normal Mode, OUTA is always on when a valid supply is present. OUTB is connected to a valid supply when the ENB input is high.
In Control Mode, OUTA behaves the same as Normal Mode and OUTB is controlled by a combination of monitored inputs and valid supplies on VDD1 and VDD2. When a valid VDD is available, the device waits for a rising input on ENB and then disconnects OUTB until the next falling RXH transition. Once the next falling RXH transition occurs, the device reconnects OUTB.
In either mode, when a valid VDD is not available, the TPS22986 opens all switches and the outputs OUTA and OUTB become high impedance. When the connected VDD exceeds 3.6V, it is disconnected from the outputs.
The TPS22986 is available in a 1.6mm x 1.6mm WCSP package.