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Functional Description

The USB1T1104 transceiver is designed to convert CMOS data

into USB differential bus signal levels and to convert USB differ-

ential bus signal to CMOS data.

To minimize EMI and noise the outputs are edge rate controlled

with the rise and fall times controlled and defined for full speed

data rates. The rise, fall times are balanced between the differ-

ential pins to minimize skew.

Table 1 describes the specific pin functionality selection.

Table 2, Table 3, and Table 4 describe the specific Truth Tables

for Driver and Receiver operating functions.

The USB1T1104 also has the capability of various power supply

configurations to support mixed voltage supply applications (see

Table 5) and Power Supply Configurations and Options for

detailed descriptions.

Functional Tables

TABLE 1. Function Select

Note 1: Signal levels is function of connection and/or pull-up/pull-down resistors.

Note 2: For SUSPND = HIGH mode the differential receiver is inactive and the output RCV output is forced LOW. The out-of-suspend signaling (K) is detected via the single-

TABLE 2. Driver Function (OE = L) using Differential Input Interface Mode Pin = H

Note 3: SE0 = Single Ended Zero

TABLE 3. Driver Function (OE = L) using Single-ended Input Interface Mode Pin = L

Note 4: SE0 = Single Ended Zero

Terminal

Number

Terminal

Name

I/O

Terminal Description

Exposed

Diepad

GND

GND

GND supply down bonded to exposed diepad to be connected to the PCB GND.

SUSPND

OE

D

, D

RCV

Function

L

L

Driving &

Receiving

Active

Active

Normal Driving (Differential Receiver Active)

L

H

Receiving

(Note 1)

Active

Active

Receiving

H

L

Driving

Inactive

(Note 2)

Active

Driving during Suspend

(Differential Receiver Inactive)

HH

3-STATE

(Note 1)

Inactive

(Note 2)

Active

Low Power State

Data

L

L

SE0 (Note 3)

L

H

Differential Logic 1

H

L

Differential Logic 0

H

H

Illegal State

FSE0

Data

L

L

Differential Logic 0

L

H

Differential Logic 1

H

L

SE0 (Note 4)

H

H

SE0 (Note 4)