1

2

3

8

7

6

Power Ground

IN

EN1

EN2

FAULT1

OUT1

OUT2

4

5

FAULT2

GND

TPS2052C, TPS2062C, TPS2062C-2, TPS2066C, TPS2066C-2

TPS2060C, TPS2064C, TPS2064C-2, TPS2002C, TPS2003C

www.ti.com

SLVSAX6H – OCTOBER 2011 – REVISED DECEMBER 2015

11 Power Supply Recommendations

11.1 Self-Powered and Bus-Powered Hubs

A Self-Powered Hub (SPH) has a local power supply that powers embedded functions and downstream ports.

This power supply must provide between 4.75 V to 5.25 V to downstream facing devices under full-load and no-

load conditions. SPHs are required to have current-limit protection and must report overcurrent conditions to the

USB controller.

Typical SPHs are desktop PCs, monitors, printers, and stand-alone hubs.

A Bus-Powered Hub (BPH) obtains all power from an upstream port and often contains an embedded function. It

must power up with less than 100 mA. The BPH usually has one embedded function, and power is always

available to the controller of the hub. If the embedded function and hub require more than 100 mA on power up,

the power to the embedded function may need to be kept off until enumeration is completed. This is

accomplished by removing power or by shutting off the clock to the embedded function. Power switching the

embedded function is not necessary if the aggregate power draw for the function and controller is less than 100

mA. The total current drawn by the bus-powered device is the sum of the current to the controller, the embedded

function, and it is limited to 500 mA from an upstream port.

11.2 Low-Power Bus-Powered and High-Power Bus-Powered Functions

Both low-power and high-power bus-powered functions obtain all power from upstream ports. Low-power

functions always draw less than 100 mA; high-powered functions must draw less than 100 mA at power up and

can draw up to 500 mA after enumeration. If the load of the function is more than the parallel combination of

44

Ω and 10 µF at power up, the device must implement inrush current limiting.

12 Layout

12.1 Layout Guidelines

•

Place the 100-nF bypass capacitor near the IN and GND pins, and make the connections using a low-

inductance trace.

•

When large transient currents are expected on the output, TI recommends placing a high-value electrolytic

capacitor and a 100-nF bypass capacitor on the output pin.

•

The PowerPAD should be directly connected to PCB ground plane using wide and short copper trace.

12.2 Layout Example

Figure 34. Layout Recommendation

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Product Folder Links: TPS2052C TPS2062C TPS2062C-2 TPS2066C TPS2066C-2 TPS2060C TPS2064C

TPS2064C-2 TPS2002C TPS2003C