FT232BQ USB UART ( USB - Serial) I.C.
4.1 Signal Descriptions
Table 1 - FT232BQ - PINOUT DESCRIPTION
UART INTERFACE GROUP
Pin#
25
24
23
22
21
20
19
18
Signal
TXD
Type
OUT
IN
Description
Transmit Asynchronous Data Output
RXD
Receive Asynchronous Data Input
RTS#
CTS#
DTR#
DSR#
DCD#
RI#
OUT
IN
Request To Send Control Output / Handshake signal
Clear To Send Control Input / Handshake signal
Data Terminal Ready Control Output / Handshake signal
Data Set Ready Control Input / Handshake signal
Data Carrier Detect Control Input
OUT
IN
IN
IN
Ring Indicator Control Input. When the Remote Wakeup option is enabled in the
EEPROM, taking RI# low can be used to resume the PC USB Host controller
from suspend.
16
TXDEN
OUT
Enable Transmit Data for RS485
USB INTERFACE GROUP
Pin#
Signal
Type
I/O
Description
7
8
USBDP
USBDM
USB Data Signal Plus ( Requires 1.5k pull-up to 3V3OUT or RSTOUT# )
USB Data Signal Minus
I/O
EEPROM INTERFACE GROUP
Pin#
32
Signal
Type
Description
EECS
I/O
EEPROM – Chip Select. For 48MHz operation pull EECS to GND using a 10K
resistor. For 6MHz operation no resistor is required. Tri-State during device reset.
**Note 1
1
2
EESK
OUT
I/O
Clock signal to EEPROM. Tri-State during device reset, else drives out. Adding a
10K pull down resistor onto EESK will cause the FT232BQ to use USB Product
ID 6004 (hex) instead of 6001 (hex). All of the other USB device descriptors are
unchanged.**Note 1
EEDATA
EEPROM – Data I/O Connect directly to Data-In of the EEPROM and to Data-
Out of the EEPROM via a 2.2K resistor. Also, pull Data-Out of the EEPROM
to VCC via a 10K resistor for correct operation. Tri-State during device reset.
**Note 1
DS232BQ Version 1.8
© Future Technology Devices Intl. Ltd. 2005
Page 9 of 25
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