Data Sheet

Copyright © Future Technology Devices International Limited 25
FT230X USB TO BASIC UART IC
Version 1.4
Document No.: FT_000566 Clearance No.: FTDI# 260
7 Application Examples
The following sections illustrate possible applications of the FT230X. The illustrations have omitted pin
numbers for ease of understanding since the pins differ between the FT230XS and FT230XQ package
options.
7.1 USB to RS232 Converter
FT230X
1
2
3
4
5
SHIELD
Ferrite
Bead
GND
GND
VCC
GND
VCC
3V3OUT
USBDM
USBDP
VCCIO
VCC
AGND
GND
RESET#
100nF
100nF
10nF
4.7uF+
SLEEP#
CBUS1
CBUS2
TXD
RXD
RTS#
CTS#
RS232 LEVEL
CONVERTER
TXDATA
RXDATA
RTS
CTS
TXLED
RXLED
VCCIO
VCCIO
270R 270R
GND
CTS
TXDATA
RTS
RXDATA
DB9M
SHIELD
10
5
9
4
8
3
7
2
6
1
SHDN
#CBUS0
TXD
RXD
RTS#
CTS#
27R
27R
GND
47pF47pF
VCCIO
TXD
RXD
RTS#
CTS#
10k
10k10k10k
Figure 7.1 Application Example showing USB to RS232 Converter
An example of using the FT230X as a USB to RS232 converter is illustrated in Figure 7.1. In this
application, a 3V3 TTL to RS232 Level Converter IC is used on the serial UART interface of the FT230X to
convert the 3V3 levels of the FT230X to RS232 levels. This level shift can be done using line drivers from
a variety of vendors e.g. Zywyn. A useful feature on some of these devices is the SHDN# pin which can
be used to power down the device to a low quiescent current during USB suspend mode.
A suitable level shifting device is the Zywyn ZT3243F which is capable of RS232 communication at up to
1000k baud.
In example shown, the CBUS1 and CBUS2 have been configured as TXLED# and RXLED# and are being
used to drive two LEDs.