STAR GROUND AGND TO GND

SW_1.1V

FB_DCDC

MODE

TRST

MR#

VDD_1P1V

BOARD_1P8V

BOARD_3P3V

BOARD_5V

A

A

A

A

A

GRST#

U4

TPS650061

U4

TPS650061

VINDCDC

8

EN_DCDC

10

MODE

9

VINLDO1

15

EN_LDO1

3

VINLDO2

18

EN_LDO2

4

PGND

6

AGND

12

PG#

5

SW

7

FB_DCDC

11

VLDO1

14

VLDO2

17

FB_LDO1

13

FB_LDO2

16

RSTSNS

19

RST#

20

MR#

1

TRST

2

PWR_PAD

21

R30

400 k

0402

1%

C72

30 pF

R39

4.7 k

0402

L2

2.2 µH

L2

C63

22 µF

C46

22 µF

C60

22 µF

R31

475 k

0402

1%

C57

22 µF

C68

0.1 µF

N.O.

SW2

PB_SWITCH

N.O.

1

2

4

3

R32

4.7 k

0402

5%

R32

16

TUSB9261

SLLSE67I – MARCH 2011 – REVISED MARCH 2016

www.ti.com

Product Folder Links: TUSB9261

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Copyright © 2011–2016, Texas Instruments Incorporated

8.2.2 Detailed Design Procedure

8.2.2.1 PWM Terminals

The TUSB9261 has two pulse-width modulated output terminals.

Table 3 shows the default firmware configuration of PWMs.

Table 3. Default Firmware Configuration of PWMs

PWM

USAGE

0

Primary Indicator LED:

ON when there is a USB connection. OFF when there is no connection.

Blinks during disk activity (Frequency: 5 Hz for USB2 or 10 Hz for USB3).

Fades when USB is in Suspend or U3 state.

1

Power indicator LED

PWM duty cycle will be 0% when the LED should be fully ON.

8.2.2.2 JTAG Interface

The TUSB9261 supports JTAG for board-level test and debug support. Typically, these terminals are left

unconnected or routed to a header to plug in an external JTAG controller. Table 4 shows the JTAG terminal

names and internal resistor connection. The JTAG interface should be left unconnected if JTAG support is not

required.

Table 4. Internal JTAG Resistor Termination

NAME

PULL UP OR PULL

DOWN

DESCRIPTION

JTAG_TCK

Pull down

JTAG test clock

JTAG_TDI

Pull up

JTAG test data in

JTAG_TDO

Pull down

JTAG test data out

JTAG_TMS

Pull up

JTAG test mode select

JTAG_RSTZ

Pull down

JTAG reset

8.2.2.3 Voltage Regulator Schematic

8.2.2.4 SPI

A SPI system consists of one master device and one or more slave devices. The TUSB9261 is a SPI master

providing the SPI clock, data-in, data-out, and up to three chip-select terminals.