9.2.1 Design Requirements

TUSB217A requires a valid reset signal as described in the power supply recommendations section. The

capacitor at RSTN pin is not required if a micro controller drives the RSTN pin according to recommendations.

For this design example, use the parameters shown in Table 9-1, Table 9-2 and Table 9-3

Table 9-1. Design Parameters for 5-V Supply With High Loss System

PARAMETER

VALUE(1)

5 V ±10%

No

Edge and DC Boost

BOOST Level

Boost Level 1:

0-Ω

0

1.8 kΩ ±1%

1

3.6 kΩ ± 1%

2

Do Not Install (DNI)

3

RX Sensitivity

RX_SEN Level

High RX

Sensitivity Level:

kΩ

kΩ

22 kΩ - 40 kΩ (27 kΩ typical)

Do Not Install (DNI)

Low

Do Not Install (DNI)

Do Not Install (DNI)

Medium

37.5 kΩ(2)

12.5 kΩ

High

(1)

These parameters are starting values for a high loss system. Further tuning might be required based on specific host and/or device as

well as cable length and loss profile. These settings are not specific to a 5V supply system could be applicable to 3.3V supply system

as well.

(2)

This resistor is needed for a 5V supply to divide the voltage down so the RX_SEN pin voltage does not exceed 5.0V

Table 9-2. Design Parameters for 3.3-V Supply With Low to Medium Loss System

PARAMETER

VALUE(1)

3.3 V ±10%

No

Edge and DC Boost

BOOST Level

Boost Level 0:

0-Ω

0

1.8 kΩ ±1%

1

3.6 kΩ ±1%

2

Do Not Install (DNI)

3

RX Sensitivity

RX_SEN Level

Medium RX

Sensitivity Level:

22 kΩ - 40 kΩ (27 kΩ typical)

Do Not Install (DNI)

Low

Do Not Install (DNI)

Do Not Install (DNI)

Medium

Do Not Install (DNI)

22 kΩ - 40 kΩ (27 kΩ typical)

High

(1)

These parameters are starting values for a low to medium loss system. Further tuning might be required based on specific host and/or

device as well as cable length and loss profile. These settings are not specific to a 3.3V supply system could be applicable to 5V

supply system as well.

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TUSB217A

SLLSFK5 – JUNE 2021

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