Copyright 2011 Future Technology Devices International Limited
13
Document No.: FT_000329
FT232BL
/BQ USB UART IC Datasheet Version 2.2
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
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.