Copyright © 2010 Future Technology Devices International Limited

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Document Reference No.: FT_000152

USB-COM422-PLUS4 Datasheet

Version 1.1

Clearance No.: 107

1.3 Block Diagram

FTDI FT4232H

High-Speed

USB Serial Bridge

USB miniB

Client

Connector

Channel A Channel B

RS422

Level Shifter

DE-9P

Connector

A

Channel C

Channel D

RS422

Level Shifter

DE-9P

Connector

B

RS422

Level Shifter

DE-9P

Connector

C

RS422

Level Shifter

DE-9P

Connector

D

Figure 1.2 USB-COM422-PLUS4 Block Diagram

1.3.1 Block description

USB Mini B Client Connector

This connector provides the interface for connection to a USB Host or Hub port. The maximum cable

length is 5 meters, according to the USB 2.0 specification.

FTDI FT4232H

FT4232H Hi-Speed USB2.0 (480Mb/s) is a quad serial UART interface IC device. Operating system device

drivers are required in order to work with the one to provide the Virtual COM Port serial functionality.

Quad RS422 Level Shifter

The RS422 level shifter converts the signals provided by the FT4232H into the voltage levels required by

RS422 devices.

Quad DE-9P Connector (Male)

The DE-9P connector is configured in an industry standard (TIA/EIA-574) pin-out to provide connection to

RS422 peripherals through standard cables. See section 3.1.2