Datasheet

SLVA037A

Designing a USB Power Distribution System Using the TPS2014 and TPS2015 Power Distribution Switches

Notes:

1. Channel 1: Switched Port Output Voltage 1 V/div

2. Channel 2: Adjacent Output Port Voltage 1 V/div

3. Time Scale: 200 ns/div

Figure 14. Ganged Hot-Insertion Transient

In the ganged configuration of Figure 15, ferrite beads were added between the output of the

TPS2014 and filter capacitors for each port. The ferrite beads provide lossless transient

impedance between the output ports. As seen in Figure 16, the voltage droop has been greatly

reduced and now is only 300 mV, which meets the USB requirement. The droop voltage can

also be made lower by increasing the output capacitance or having some bulk capacitance on

the 5 V input.

Figure 15. Ganged Test Circuit With Ferrite Beads