Copyright © 2011 Future Technology Devices International Limited

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Document No.: FT_000329

FT232BL

Clearance No.: FTDI#

171

EEPROM interface. Though the FT232B will work without the optional EEPROM, an external 93C46

(93C56 or 93C66) EEPROM can be used to customise the USB VID, PID, Serial Number, Product

Description Strings and Power Descriptor value of the FT232B for OEM applications. Other parameters

controlled by the EEPROM include Remote Wake Up, Soft Pull Down on Power-Off and USB 2.0 descriptor

modes. The EEPROM should be a 16 bit wide configuration such as a MicroChip 93LC46B or equivalent

capable of a 1Mb/s clock rate at VCC = 4.35V to 5.25V. The EEPROM is programmable-on board over

USB using a utility available from FTDI’s web site (http://www.ftdichip.com). This allows a blank part to be

soldered onto the PCB and programmed as part of the manufacturing and test process. If no EEPROM is

connected (or the EEPROM is blank), the FT232B will use its built-in default VID, PID Product Description

and Power Descriptor Value. In this case, the device will not have a serial number as part of the USB

descriptor.