FT232R Future Technology Devices Intl Ltd., FT232R Datasheet - Page 22

• Manufacturer Part Number: FT232R
• Manufacturer: Future Technology Devices Intl Ltd.

8. Example Interface Configurations
As in the Device Configurations section, please note that pin numbers on the FT232R chip in this section have
deliberately been left out as they vary between the FT232RL and FT232RQ versions of the device. All of these
configurations apply to both package options for the FT232R device. Please refer to
pin-out and signal descriptions.
Figure 13 - Example USB to RS232 Converter Configuration
Figure 13 illustrates how to connect an FT232R as a USB to RS232 converter. A TTL – RS232 Level Converter I.C. is
used on the serial UART of the FT232R to make the RS232 level conversion. This, for example can be done using the
popular “213” series of TTL to RS232 level converters. These devices have 4 transmitters and 5 receivers in a 28-LD
SSOP package and feature an in-built voltage converter to convert the 5V (nominal) VCC to the +/- 9 volts required by
RS232. An important feature of these devices is the SHDN# pin which can power down the device to a low quiescent
current during USB suspend mode.
An example of a device which can be used for this is a Sipex SP213EHCA which is capable of RS232 communication
at up to 500kΩ baud. If a lower baud rate is acceptable, then several pin compatible alternatives are available
such as the Sipex SP213ECA , the Maxim MAX213CAI and the Analog Devices ADM213E, which are all good for
communication at up to 115,200 baud. If a higher baud rate is desired, use a Maxim MAX3245CAI part which is
capable of RS232 communication at rates of up to 1M baud. The MAX3245 is not pin compatible with the 213 series
devices, also its SHDN pin is active high, so connect it to PWREN# instead of SLEEP#.
In the above example CBUS0 and CBUS1 have been configured as TXLED# and RXLED#, and are being used to
drive two LEDs.
FT232R USB UART I.C. Datasheet Version 1.02
SHIELD
5
8.1 USB to RS232 Converter Configuration
1
2
3
4
10nF
100nF
+
Ferrite
Bead
4.7uF
+
Vcc
Vcc
100nF
VCC
USBDM
USBDP
VCCIO
RESET#
OSCI
OSCO
3V3OUT
NC
NC
A
G
N
D
FT232R
G
N
D
G
N
D
G
N
D
T
E
S
T
CBUS0
CBUS1
CBUS2
CBUS3
CBUS4
DSR#
DCD#
RTS#
CTS#
DTR#
RXD
TXD
RI#
SLEEP#
TXD
RXD
RTS#
CTS#
DTR#
DSR#
DCD#
RI#
SHDN#
© Future Technology Devices International Ltd. 2005
GPIO2
GPIO3
TXLED#
RXLED#
TXDATA
RXDATA
RTS
CTS
DTR
DSR
DCD
RI
Section 4
Vcc
270R
Vcc
for the package option
270R
RXDATA
TXDATA
DTR
CTS
RTS
DSR
DCD
RI
GND
SHIELD
5
9
4
8
3
7
2
6
1
10
DB9M