UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Clearance No.: FTDI# 125
Future Technology Devices
International Ltd
UM232R USB - Serial UART
Development Module
Datasheet
Neither the whole nor any part of the information contained in, or the product described in this manual, may be adapted or reproduced in
any material or electronic form without the prior written consent of the copyright holder. This product and its documentation are supplied
on an as-is basis and no warranty as to their suitability for any particular purpose is either made or implied. Future Technology Devices
International Ltd will not accept any claim for damages howsoever arising as a result of use or failure of this product. Your statutory rights
are not affected. This product or any variant of it is not intended for use in any medical appliance, device or system in which the failure of
the product might reasonably be expected to result in personal injury. This document provides preliminary information that may be
subject to change without notice. No freedom to use patents or other intellectual property rights is implied by the publication of this
document. Future Technology Devices International Ltd, Unit 1, 2 Seaward Place, Centurion Business Park, Glasgow G41 1HH United
Kingdom. Scotland Registered Company Number: SC136640
Copyright © Future Technology Devices International Limited
1
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Clearance No.: FTDI# 125
1 Introduction
The UM232R is a development module which uses FTDI’s FT232RL, one of FTDI’s range of USB to UART
interface integrated circuit devices. The FT232RL is a USB to serial UART interface with optional clock
generator output, and the FTDIChip-ID™ security dongle feature. In addition, asynchronous and synchronous
bit bang interface modes are available. The FT232RL adds two new functions compared with its predecessors,
effectively making it a “3-in-1” chip for some application areas. The internally generated clock (6MHz, 12MHz,
24MHz, and 48MHz) can be brought out of the device and used to drive a microcontroller or external logic. A
unique number (the FTDIChip-ID™) is burnt into the device during manufacture and is readable over USB,
thus forming the basis of a security dongle which can be used to protect customer application software from
being copied. (Safe-Guard-IT). The UM232R is supplied on a PCB which is designed to plug into a standard
0.6” wide 24 pin DIP socket. All components used, including the FT232RL are Pb-free (RoHS compliant).
Figure 1.1 – UM232R USB Serial UART Development Module
Copyright © Future Technology Devices International Limited
2
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Clearance No.: FTDI# 125
Table of Contents
1
Introduction .................................................................... 2
2
Typical Application .......................................................... 5
3
2.1
Driver Support .......................................................................... 5
2.2
Features .................................................................................... 6
FT232RL Features and Enhancement .............................. 7
3.1
4
Key Features ............................................................................. 7
UM232R Pin Out and Signal Descriptions ...................... 10
4.1
UM232R Pin Out ...................................................................... 10
4.2
Signal Descriptions ................................................................. 10
4.3
Jumper Configuration Options ................................................ 12
4.4
CBUS Signal Options ............................................................... 12
5
Module Dimensions ....................................................... 14
6
FT232RL Device Characteristics and Ratings ................. 15
7
6.1
Absolute Maximum Ratings ..................................................... 15
6.2
DC Characteristics ................................................................... 15
6.3
EEPROM Reliability Characteristics ......................................... 18
6.4
Internal Clock Characteristics ................................................. 18
Module Configurations .................................................. 19
7.1
BUS Powered Configuration .................................................... 19
7.2
Self Powered Configuration .................................................... 20
7.3
USB Bus Powered with Power Switching Configuration .......... 21
7.4
Bus Powered with 3.3V Logic Drive / IO Supply Voltage ......... 22
8
UM232R Module Circuit Schematic ................................ 24
9
Internal EEPROM Configuration..................................... 25
10 Contact Information ...................................................... 27
Appendix A – References ................................................... 28
Document References ..................................................................... 28
Acronyms and Abbreviations ........................................................... 28
Appendix B – List of Tables and Figures ............................. 29
Copyright © Future Technology Devices International Limited
3
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Clearance No.: FTDI# 125
List of Tables ................................................................................... 29
List of Figures ................................................................................. 29
Appendix C – Revision History ........................................... 30
Copyright © Future Technology Devices International Limited
4
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Clearance No.: FTDI# 125
2 Typical Application
USB to RS232 / RS422 / RS485 Converters
Upgrading Legacy Peripherals to USB
Cellular and Cordless Phone USB data transfer cables and interfaces
Interfacing MCU / PLD / FPGA based designs to USB
USB Audio and Low Bandwidth Video data transfer
PDA to USB data transfer
USB Smart Card Readers
USB Instrumentation
USB Industrial Control
USB MP3 Player Interface
USB FLASH Card Reader / Writers
Set Top Box PC – USB interface
USB Digital Camera Interface
USB Hardware Modems
USB Wireless Modems
USB Bar Code Readers
USB Software / Hardware Encryption Dongles
USB Medical applications
2.1 Driver Support
Royalty-Free VIRTUAL COM PORT (VCP)
DRIVERS for:
Royalty-Free D2XX Direct Drivers (USB
Drivers + DLL S/W Interface):
Windows 10 32,64-bit
Windows 10 32,64-bit
Windows 8 / 8.1 32,64-bit
Windows 8 / 8.1 32,64-bit
Windows 7 32,64-bit
Windows 7 32,64-bit
Windows Vista
Windows Vista
Windows XP 32,64-bit
Windows XP 32,64-bit
Windows XP Embedded
Windows XP Embedded.
Windows 98, 98SE, ME, 2000, Server 2003,
XP and Server 2008
Windows 98, 98SE, ME, 2000, Server 2003,
XP and Server 2008
Windows CE.NET 4.2 , 5.0 and 6.0
Windows CE.NET 4.2, 5.0 and 6.0
MAC OS OS-X
MAC OS OS-X
Linux 2.4 and greater
Linux 2.4 and greater
The drivers listed above are all available to download for free from www.ftdichip.com. Various 3rd Party
Drivers are also available for various other operating systems – visit www.ftdichip.com for details.
Copyright © Future Technology Devices International Limited
5
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Clearance No.: FTDI# 125
2.2 Features
The UM232R has the following features:
Single chip USB to UART synchronous serial
data transfer interface
Entire USB protocol handled on the chip –
No USB-specific firmware programming
required.
UART interface support for 7 or 8 data bits,
1 or 2 stop bits and odd / even / mark /
space / no parity.
Fully assisted hardware or X-On / X-Off
software handshaking.
On board jumper allows for selection of USB
bus powered supply or self-powered
supply. Integrated 3.3V level converter for
USB I/O.
Integrated level converter on UART and
CBUS for interfacing to 5V – 1.8V Logic.
On board jumper allows for selection of
UART and CBUS interface IO voltage.
Data transfer rates from 300 baud to 3
Megabaud (RS422 / RS485 and at TTL
levels) and 300 baud to 1 Megabaud
(RS232).
True 5V / 3.3V / 2.8V / 1.8V CMOS drive
output and TTL input.
High I/O pin output drive option.
FTDI’s royalty-free VCP and D2XX drivers
eliminate the requirement for USB driver
development in most cases.
Integrated USB resistors.
Integrated power-on-reset circuit.
In-built support for event characters and
line break condition.
USB FTDIChip-ID™ feature.
Fully integrated clock – no external crystal,
oscillator, or resonator required.
Configurable CBUS I/O pins.
Auto transmit buffer control for RS485
applications.
Fully integrated AVCC supply filtering – No
separate AVCC pin and no external R-C
filter required.
UART signal inversion option.
Transmit and receive LED drive signals.
USB bulk transfer mode.
New 48MHz, 24MHz, 12MHz, and 6MHz
clock output signal Options for driving
external MCU or FPGA.
+4.0V to +5.25V Single Supply Operation.
Low operating and USB suspend current.
Low USB bandwidth consumption.
UHCI / OHCI
compatible
USB 2.0 Full Speed compatible.
Receive and transmit buffers for high data
throughput.
Adjustable receive buffer timeout.
Synchronous and asynchronous bit bang
mode interface options with RD# and WR#
strobes.
New CBUS bit bang mode option.
Support for USB suspend and resume.
Integrated 1024 bit internal EEPROM for
storing USB VID, PID, serial number and
product description strings, and CBUS I/O
configuration.
Device supplied preprogrammed
unique USB serial number.
/
-40°C
to
85°C
temperature range.
with
EHCI
host
extended
controller
operating
Supplied in PCB designed to fit a standard
15.0mm (0.6”) wide 24 pin DIP socket.
Pins are on a 2.60mm (0.1”) pitch.
On board USB ‘B’ socket allows module to
be connected to a PC via a standard A to B
USB cable.
Support for bus powered, self-powered,
and
high-power
bus
powered
USB
configurations.
Copyright © Future Technology Devices International Limited
6
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Clearance No.: FTDI# 125
3 FT232RL Features and Enhancement
3.1 Key Features
This section summarises the key features and enhancements of the FT232RL IC device which is used on the
UM232R Module. For further details, consult the FT232R datasheet, which is available from
www.ftdichip.com.
Integrated Clock Circuit – Previous generations of FTDI’s USB UART devices required an external crystal
or ceramic resonator. The clock circuit has now been integrated onto the device meaning that no crystal or
ceramic resonator is required. However, if preferred, an external 12MHz crystal can be used as the clock
source. Note that the UM232R does not provide access to these pins on the FT232R device.
Integrated EEPROM – Previous generations of FTDI’s USB UART devices required an external EEPROM if
the device were to use USB Vendor ID (VID), Product ID (PID), serial number and product description
strings other than the default values in the device itself. This external EEPROM has now been integrated
onto the FT232R chip meaning that all designs have the option to change the product description strings. A
user area of the internal EEPROM is available for storing additional data. The internal EEPROM is
programmable in circuit, over USB without any additional voltage requirement.
Preprogrammed EEPROM – The FT232R is supplied with its internal EEPROM pre-programmed with a
serial number which is unique to each individual device. This, in most cases, will remove the need to
program the device EEPROM.
Integrated USB Resistors – Previous generations of FTDI’s USB UART devices required two external
series resistors on the USBDP and USBDM lines, and a 1.5 kΩ pull up resistor on USBDP. These three
resistors have now been integrated onto the device.
Integrated AVCC Filtering – Previous generations of FTDI’s USB UART devices had a separate AVCC pin –
the supply to the internal PLL. This pin required an external R-C filter. The separate AVCC pin is now
connected internally to VCC, and the filter has now been integrated onto the chip.
Less External Components – Integration of the crystal, EEPROM, USB resistors, and AVCC filter will
substantially reduce the bill of materials cost for USB interface designs using the FT232R compared to its
FT232BM predecessor.
Configurable CBUS I/O Pin Options – There are now 5 configurable Control Bus (CBUS) lines. Options
are TXDEN – transmit enable for RS485 designs, PWREN# - Power control for high power, bus powered
designs, TXLED# - for pulsing an LED upon transmission of data, RXLED# - for pulsing an LED upon
receiving data, TX&RXLED# - which will pulse an LED upon transmission OR reception of data, SLEEP# indicates that the device going into USB suspend mode, CLK48 / CLK24 / CLK12 / CLK6 – 48MHz,
24MHz,12MHz, and 6MHz clock output signal options. There is also the option to bring out bit bang mode
read and write strobes (see below). The CBUS lines can be configured with any one of these output options
by setting bits in the internal EEPROM. The device is supplied with the most commonly used pin definitions
pre-programmed – see Section 9 for details.
Enhanced Asynchronous Bit Bang Mode with RD# and WR# Strobes – The FT232R supports FTDI’s
BM chip bit bang mode. In bit bang mode, the eight UART lines can be switched from the regular interface
mode to an 8-bit general purpose I/O port. Data packets can be sent to the device and they will be
sequentially sent to the interface at a rate controlled by an internal timer (equivalent to the baud rate
prescaler). With the FT232R device this mode has been enhanced so that the internal RD# and WR#
strobes are now brought out of the device which can be used to allow external logic to be clocked by
accesses to the bit bang I/O bus. This option will be described more fully in a separate application note.
Synchronous Bit Bang Mode – Synchronous bit bang mode differs from asynchronous bit bang mode in
that the interface pins are only read when the device is written to. Thus making it easier for the controlling
program to measure the response to an output stimulus as the data returned is synchronous to the output
data. The feature was previously seen in FTDI’s FT2232C device. This option will be described more fully in
a separate application note.
Copyright © Future Technology Devices International Limited
7
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Clearance No.: FTDI# 125
CBUS Bit Bang Mode – This mode allows four of the CBUS pins to be individually configured as GPIO pins,
similar to Asynchronous bit bang mode. It is possible to use this mode while the UART interface is being
used, thus providing up to four general purpose I/O pins which are available during normal operation. An
application note describing this feature is available separately from www.ftdichip.com.
Lower Supply Voltage – Previous generations of the chip required 5V supply on the VCC pin. The FT232R
will work with a VCC supply in the range 4.0V to 5.25V. Bus powered designs would still take their supply
from the 5V on the USB bus.
Integrated Level Converter on UART Interface and Control Signals – VCCIO pin supply can be from
1.8V to 5V. Connecting the VCCIO pin to 1.8V, 2.8V, or 3.3V allows the device to directly interface to 1.8V,
2.8V or 3.3V and other logic families without the need for external level converter I.C. devices.
5V / 3.3V / 2.8V / 1.8V Logic Interface – The FT232R provides true CMOS Drive Outputs and TTL level
Inputs.
Integrated Power-On-Reset (POR) Circuit- The device incorporates an internal POR function. A RESET#
pin is available in order to allow external logic to reset the FT232R where required. However, for many
applications the RESET# pin can be left unconnected, or pulled up to VCCIO.
Lower Operating and Suspend Current – The device operating supply current has been further reduced
to 15mA, and the suspend current has been reduced to around 70μA. This allows greater margin for
peripheral designs to meet the USB suspend current limit of 500μA.
Low USB Bandwidth Consumption – The operation of the USB interface to the FT232R has been
designed to use as little as possible of the total USB bandwidth available from the USB host controller.
High Output Drive Option – The UART interface and CBUS I/O pins can be made to drive out at three
times the standard signal drive level thus allowing multiple devices to be driven, or devices that require
greater signal drive strength to be interfaced to the FT232R. This option is enabled in the internal EEPROM.
Power Management Control for USB Bus Powered, High Current Designs – The PWREN# signal can
be used to directly drive a transistor or P-Channel MOSFET in applications where power switching of
external circuitry is required. An option in the internal EEPROM makes the device gently pull down on its
UART interface lines when the power is shut off (PWREN# is high). In this mode any residual voltage on
external circuitry is bled to GND when power is removed, thus ensuring that external circuitry controlled by
PWREN# resets reliably when power is restored.
UART Pin Signal Inversion – The sense of each of the eight UART signals can be individually inverted by
setting options in the internal EEPROM. Thus, CTS# (active low) can be changed to CTS (active high), or
TXD can be changed to TXD#.
FTDIChip-ID™ - Each FT232R is assigned a unique number which is burnt into the device at manufacture.
This ID number cannot be reprogrammed by product manufacturers or end-users. This allows the possibility
of using FT232R based dongles for software licensing. Further to this, a renewable license scheme can be
implemented based on the FTDIChip-ID™ number when encrypted with other information. This encrypted
number can be stored in the user area of the FT232R internal EEPROM, and can be decrypted, then
compared with the protected FTDIChip-ID™ to verify that a license is valid. Web based applications can be
used to maintain product licensing this way. An application note describing this feature is available
separately from www.ftdichip.com.
Improved EMI Performance – The reduced operating current and improved on-chip VCC decoupling
significantly improves the ease of PCB design requirements in order to meet FCC, CE and other EMI related
specifications.
Programmable Receive Buffer Timeout – The receive buffer timeout is used to flush remaining data
from the receive buffer. This time defaults to 16ms, but is programmable over USB in 1ms increments from
1ms to 255ms, thus allowing the device to be optimised for protocols that require fast response times from
short data packets.
Copyright © Future Technology Devices International Limited
8
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Clearance No.: FTDI# 125
Baud Rates – The FT232R supports all standard baud rates and non-standard baud rates from 300 Baud
up to 3 Megabaud. Achievable non-standard baud rates are calculated as follows –Baud Rate = 3000000 /
(n + x) where ‘n’ can be any integer between 2 and 16,384 (= 214 ) and ‘x’ can be a sub-integer of the
value 0, 0.125, 0.25, 0.375, 0.5, 0.625, 0.75, or 0.875. When n = 1, x = 0, i.e. baud rate divisors with
values between 1 and 2 are not possible. This gives achievable baud rates in the range 183.1 baud to
3,000,000 baud. When a non-standard baud rate is required simply pass the required baud rate value to
the driver as normal, and the FTDI driver will calculate the required divisor, and set the baud rate. See
FTDI application note AN232B-05 for more details.
Extended Operating Temperature Range – The FT232R operates over an extended temperature range
of -40º to +85º C thus allowing the device to be used in automotive and industrial applications.
Package Options – The FT232R is available in two packages – a compact 28 pin SSOP ( FT232RL) and an
ultra-compact 5mm x 5mm pinless QFN-32 package ( FT232RQ). Both packages are lead ( Pb ) free, and
use a ‘green’ compound. Both packages are fully compliant with European Union directive 2002/95/EC.
Copyright © Future Technology Devices International Limited
9
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Clearance No.: FTDI# 125
4 UM232R Pin Out and Signal Descriptions
4.1
UM232R Pin Out
Figure 4.1 Module Pin Out and Jumper Locations
4.2 Signal Descriptions
Pin
Name
Type
Description
1
TXD
Output
Transmit Asynchronous Data Output.*
2
DTR#
Output
Data Terminal Ready Control Output / Handshake Signal.*
3
RTS#
Output
Request to Send Control Output / Handshake Signal.*
No.
+1.8V to +5.25V supply to the UART Interface and CBUS I/O pins (1...3, 5, 6,
9...14, 22, 23).
4
VIO
PWR
In USB bus powered designs connect to 3V3 to drive out at 3.3V levels
(connect jumper J1 pins 1 and 2 together), or connect to VCC to drive out at
5V CMOS level (connect jumper J1 pins 2 and 3 together). This pin can also
be supplied with an external 1.8V – 2.8V supply in order to drive out at lower
levels. It should be noted that in this case this supply should originate from
the same source as the supply to VCC. This means that in bus powered
designs a regulator which is supplied by the 5V on the USB bus should be
used.
Copyright © Future Technology Devices International Limited
10
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Pin
Clearance No.: FTDI# 125
Name
Type
Description
5
RXD
Input
Receiving Asynchronous Data Input.*
6
RI#
Input
Ring Indicator Control Input. When remote wake up is enabled in the internal
EEPROM taking RI# low >20ms can be used to resume the PC USB host
controller from suspend.*
7, 24
GND
PWR
Module Ground Supply Pins
8
DSR#
Input
Data Set Ready Control Input / Handshake Signal.*
9
DCD#
Input
Data Carrier Detect Control Input.
10
CTS#
Input
Clear To Send Control Input / Handshake Signal.*
11
CB4
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the device
internal EEPROM. Factory Default pin function is SLEEP#. See CBUS Signal
Options, Table 4.4.*
12
CB2
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the device
internal EEPROM. Factory Default pin function is TXDEN. See CBUS Signal
Options,Table 4.4.*
13
SLD
GND
USB Cable Shield.
Output
5V Power output USB port. For a low power USB bus powered design, up to
100mA can be sourced from the 5V supply on the USB bus. A maximum of
500mA can be sourced from the USB bus in a high power USB bus powered
design.
No.
14
15, 21
USB
VCC
PWR
or
Output
These two pins are internally connected on the module PCB. To power the
module from the 5V supply on USB bus connects jumper J2 pins 1 and 2
together (this is the module default configuration). In this case these pins
would have the same description as pin 14.
To use the UM232R module in a self-powered configuration ensure that
jumper J2 pins 1 and 2 are not connected together, and apply an external
4.0V to 5.25V supply to one of these pins.
17
PU1
Contro
l
Pull up resistor pin connection 2. Connect to pin 20 (RST#) in a self-powered
configuration.
16
PU2
Contro
l
Pull up resistor pin connection 1. Connect to pin 14 (USB) in a self-powered
configuration.
18
CB3
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the device
internal EEPROM. Factory Default pin Function is PWREN#. See CBUS Signal
Options, Table 4.4.*
3.3V output from integrated L.D.O. regulator. This pin is decoupled to ground
on the module PCB with a 10nF capacitor. The prime purpose of this pin is to
provide the internal 3.3V supply to the USB transceiver cell and the internal
1.5kΩ pull up resistor on USBDP. Up to 50mA can be drawn from this pin to
power external logic if required. This pin can also be used to supply the
FT232RL’s VCCIO pin by connecting this pin to pin 4 (VIO), or by connecting
together pins 1 and 2 on jumper J1.
19
3V3
Output
20
RST#
Input
Can be used by an external device to reset the FT232R. If not required can be
left unconnected, or pulled up to VCCIO.
22
CB1
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the device
internal EEPROM. Factory Default pin Function is RXLED#. See CBUS Signal
Copyright © Future Technology Devices International Limited
11
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Pin
No.
Name
Type
Clearance No.: FTDI# 125
Description
Options, Table 4.4.*
23
CB0
I/O
Configurable CBUS I/O Pin. Function of this pin is configured in the device
internal EEPROM. Factory Default pin Function is TXLED#. See CBUS Signal
Options,Table 4.4.*
Table 4.1Module Pin Out Description
* When used in Suspend, these pins are pulled to VCCIO via internal 200kΩ resistors. These pins can be
programmed to gently pull low during USB suspend (PWREN# = “1”) by setting an option in the internal
EEPROM.
4.3 Jumper Configuration Options
Pin
Name
Type
Description
1
3V3
Output
Connect this pin to pin 2 to create 3V3 I/O.
2
VIO
PWR
Input Pin for Chip VCCIO
3
VCC
PWR
Connect this pin to pin 2 to create 5V I/O
Table 4.2 Jumper J1 Pin Description
Pin
No.
Name
Type
Description
USB
PWR
5V Power output USB port. For a low power USB bus power design, up to
100mA can be sourced from the 5V supply on the USB bus. A maximum of
500 mA can be sourced from the USB bus in a high power USB bus powered
design.
VCC
PWR
or
Output
No.
1
2
Board supply input. Connect to jumper J2 pin 1 in order to supply the board
from the USB bus.
This pin is internally connected to the VCC DIP pins. Remove the jumper
connector in a self-powered design.
Table 4.3 Jumper J2 Pin Description
4.4 CBUS Signal Options
The following options can be configured on the CBUS I/O pins. These options are all configured in the
internal EEPROM using the utility software FT_PROG, which can be downloaded from the www.ftdichip.com.
The default configuration is described in Section 9.
CBUS Signal
Available On CBUS Pin
Description
TXDEN#
CBUS0, CBUS1, CBUS2, CBUS3,
CBUS4
Enable transmit data for RS485
PWREN#
CBUS0, CBUS1, CBUS2, CBUS3,
CBUS4
Goes low after the device is configured by USB,
then high during USB suspend. Can be used to
control power to external logic in high power
designs. Needs 10k pull up to VCC.
Option
Copyright © Future Technology Devices International Limited
12
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
CBUS Signal
Clearance No.: FTDI# 125
Available On CBUS Pin
Description
TXLED#
CBUS0, CBUS1, CBUS2, CBUS3,
CBUS4
Transmit data LED drive – pulses low when
transmitting data via USB.
RXLED#
CBUS0, CBUS1, CBUS2, CBUS3,
CBUS4
Receive data LED drive – pulses low when receiving
data via USB.
TX&RXLED#
CBUS0, CBUS1, CBUS2, CBUS3,
CBUS4
LED drive – pulses low when transmitting or
receiving data via USB. See
CBUS0, CBUS1, CBUS2, CBUS3,
CBUS4
Goes low during USB suspend mode. Typically used
to power down an external TTL to RS232 level
converter I.C. in USB to RS232 converter designs.
Option
SLEEP#
CLK48
CBUS0, CBUS1, CBUS2, CBUS3,
CBUS4
48MHz Clock output.
CLK24
CBUS0, CBUS1, CBUS2, CBUS3,
CBUS4
24 MHz Clock output.
CLK12
CBUS0, CBUS1, CBUS2, CBUS3,
CBUS4
12 MHz Clock output.
CLK6
CBUS0, CBUS1, CBUS2, CBUS3,
CBUS4
6 MHz Clock output.
CbitBangI/O
CBUS0, CBUS1, CBUS2, CBUS3
CBUS bit bang mode option. Allows up to 4 of the
CBUS pins to be used as general purpose I/O.
Configured individually for CBUS0, CBUS1, CBUS2
and CBUS3 in the internal EEPROM. A separate
application note will describe in more detail how to
use CBUS bit bang mode. (www.ftdichip.com)
BitBangWRn
CBUS0, CBUS1
Synchronous and asynchronous bit bang mode
WR# strobe Output.
BitBangRDn
CBUS0, CBUS1, CBUS2, CBUS3
Synchronous and asynchronous bit bang mode
RD# strobe Output.
Table 4.4 CBUS Signal Options
Copyright © Future Technology Devices International Limited
13
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Clearance No.: FTDI# 125
5 Module Dimensions
Figure 5.1 UM232R Module Dimensions
All dimensions are in millimetres, with inches in parenthesis. These should be used as a guide only.
The FT232RL is supplied in a RoHS compliant 28 pin SSOP package. The package is lead (Pb) free and uses
a ‘green# compound. The date code format is YYXX where XX = 2 digit week number, YY = 2 digit year
number.
The UM232R module uses exclusively lead free components, and are fully compliant with European Union
directive 2002/95/EC.
Copyright © Future Technology Devices International Limited
14
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Clearance No.: FTDI# 125
6 FT232RL Device Characteristics and Ratings
6.1 Absolute Maximum Ratings
The absolute maximum ratings for the FT232R devices are as follows. These are in accordance with the
Absolute Maximum Rating System (IEC 60134). Exceeding these may cause permanent damage to the
device.
Parameter
Value
Unit
Storage Temperature
-65°C to 150°C
Degrees
C
Floor Life (Out of Bag) At Factory Ambient
168 Hours
Hours
(30°C / 60% Relative Humidity)
(IPC/JEDEC J-STD-033A MSL Level 3
Compliant)*
Ambient Temperature (Power Applied)
-40°C to 85°C
Degrees
C
VCC Supply Voltage
-0.5 to +6.00
V
D.C. Input Voltage – USBDP and USBDM
-0.5 to +3.8
V
D.C. Input Voltage – High Impedance
Bidirectional
-0.5 to + (VCC +0.5)
V
D.C. Input Voltage – All Other Inputs
-0.5 to + (VCC +0.5)
V
D.C. Output Current – Outputs
24
mA
D.C. Output Current – Low Impedance
Bidirectional
24
mA
Power Dissipation (VCC = 5.25V)
500
Table 6.1 Absolute Maximum Ratings
mW
* If devices are stored out of the packaging beyond this time limit the devices should be baked before use.
The devices should be ramped up to a temperature of 125°C and baked for up to 17 hours.
6.2 DC Characteristics
DC Characteristics (Ambient Temperature = -40 to 85°C)
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
VCC1
VCC Operating Supply Voltage
4.0
---
5.25
V
VCC2
VCCIO Operating Supply
Voltage
1.8
---
5.25
V
Icc1
Operating Supply Current
---
15
---
mA
Normal
Operation
Icc2
Operating Supply Current
50
70
100
Table 6.2 Operating Voltage and Current
μA
USB Suspend
Because the UM232R module does not provide access to the OSCI and OSCO pins, the VCC range of this
module has a minimum value of +4.0V. The FT232R device on this module is capable of operating down to
+3.3V but its internal oscillator is only specified for operation down to +4.0V and so an external crystal
must be used when VCC is in the range +3.3V to +4.0V.
Copyright © Future Technology Devices International Limited
15
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Parameter
Description
Minimum
Typical
Maximum
Units
Clearance No.: FTDI# 125
Conditions
Voh
Output Voltage High
3.2
4.1
4.9
V
I source = 2mA
Vol
Output Voltage Low
0.3
0.4
0.6
V
I sink = 2mA
Vin
Input Switching Threshold
1.3
1.6
1.9
V
**
Vhys
Input Switching Hysteresis
50
55
60
mV
**
Table 6.3 UART and CBUS I/O Pin Characteristics (VCCIO = 5.0V, Standard Drive Level)
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
2.2
2.7
3.2
V
I source = 1mA
Vol
Output Voltage Low
0.3
0.4
0.5
V
I sink = 2mA
Vin
Input Switching Threshold
1.0
1.2
1.5
V
**
Vhys
Input Switching Hysteresis
20
25
30
mV
**
Table 6.4 UART and CBUS I/O Pin Characteristics (VCCIO = 3.3V, Standard Drive Level)
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
2.1
2.6
3.1
V
I source = 1mA
Vol
Output Voltage Low
0.3
0.4
0.5
V
I sink = 2mA
Vin
Input Switching Threshold
1.0
1.2
1.5
V
**
Vhys
Input Switching Hysteresis
20
25
30
mV
**
Table 6.5 UART and CBUS I/O Pin Characteristics (VCCIO = 2.8V, Standard Drive Level)
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
3.2
4.1
4.9
V
I source = 6mA
Vol
Output Voltage Low
0.3
0.4
0.6
V
I sink = 6mA
Vin
Input Switching Threshold
1.3
1.6
1.9
V
**
Vhys
Input Switching Hysteresis
50
55
60
mV
**
Table 6.6 UART and CBUS I/O Pin Characteristics (VCCIO = 5.0V, High Drive Level)
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
2.2
2.8
3.2
V
I source = 3mA
Vol
Output Voltage Low
0.3
0.4
0.6
V
I sink = 8mA
Vin
Input Switching Threshold
1.0
1.2
1.5
V
**
Vhys
Input Switching Hysteresis
20
25
30
mV
**
Table 6.7 UART and CBUS I/O Pin Characteristics (VCCIO = 3.3V, High Drive Level)
Copyright © Future Technology Devices International Limited
16
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Parameter
Description
Clearance No.: FTDI# 125
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
2.1
2.8
3.2
V
I source = 3mA
Vol
Output Voltage Low
0.3
0.4
0.6
V
I sink = 8mA
Vin
Input Switching Threshold
1.0
1.2
1.5
V
**
Vhys
Input Switching Hysteresis
20
25
30
mV
**
Table 6.8 UART and CBUS I/O Pin Characteristics (VCCIO = 2.8V, High Drive Level)
** Inputs have an internal 200kΩ pull-up resistor to VCCIO
Parameter
Vin
Vhys
Parameter
Uvoh
Description
Input Switching Threshold
Minimum
Typical
Maximum
Units
1.3
1.6
1.9
V
Conditions
Input Switching Hysteresis
50
55
60
mV
Table 6.9 RESET# and TEST Pin Characteristics
Description
I/O Pins Static Output (High)
Uvol
I/O Pins Static Output (Low)
Uvse
Minimum
2.8
Typical
---
Maximum
3.6
Units
Conditions
V
RI = 1.5kΩ to
3V3Out (D+) RI
= 15KΩ to GND
(D-)
RI = 1.5kΩ to
3V3Out (D+) RI
= 15kΩ to GND
(D-)
0
---
0.3
V
Single Ended Rx Threshold
0.8
---
2.0
V
Ucom
Differential Common Mode
0.8
---
2.5
V
UVDif
Differential Input Sensitivity
0.2
---
---
V
UdrvZ
Driver Output Impedance
26
29
44
Ohms
Table 6.10 USB I/O Pin (USBDP, USBDM) Characteristics
***
*** Driver Output Impedance includes the internal USB series resistors on USBDP and USBDM pins
Copyright © Future Technology Devices International Limited
17
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Clearance No.: FTDI# 125
6.3 EEPROM Reliability Characteristics
The internal 1024 bit EEPROM has the following reliability characteristics:
Parameter
Value
Unit
Data Retention
15
Years
Read / Write Cycle 100,000 Cycles
Table 6.11 EEPROM Characteristics
6.4 Internal Clock Characteristics
The internal Clock Oscillator has the following characteristics:
Parameter
Value
Unit
Minimum
Typical
Maximum
Frequency of Operation
11.98
12.00
12.02
MHz
Clock Period
83.19
83.33
83.47
ns
Duty Cycle
45
50
55
Table 6.12 Internal Clock Characteristics
Copyright © Future Technology Devices International Limited
%
18
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Clearance No.: FTDI# 125
7 Module Configurations
7.1 BUS Powered Configuration
Figure 7.1 Bus Powered Configuration
Figure 7.1 illustrates the UM232R module in a typical USB bus powered design configuration. This can easily
be done by fitting the jumper link on J2, as shown above. The UM232R is supplied in this configuration by
default.
A USB Bus Powered device gets its power from the USB bus. Basic rules for USB Bus Power devices are as
follows:
i) On plug-in to USB, the device must draw no more than 100mA.
ii) On USB suspend the device must draw no more than 500μA.
iii) A Bus Powered High Power USB Device (one that draws more than 100mA) should use one of the
CBUS pins configured as PWREN# and use it to keep the current below 100mA on plug-in and 500μA
on USB suspend.
iv)
A device that consumes more than 100mA cannot be plugged into a USB Bus Powered Hub.
v) No device can draw more that 500mA from the USB Bus.
Interfacing the UM232R module to a microcontroller (MCU), or other logic for a bus powered design would
be done in exactly the same way as for a self-powered design (see Section 7.2), except that the MCU or
external logic would take its power supply from the USB bus (either the 5V on the USB pin, or 3.3V on the
3V3 pin).
Copyright © Future Technology Devices International Limited
19
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Clearance No.: FTDI# 125
7.2 Self Powered Configuration
Vcc = 3.3V – 5V
Vcc = 4.0V – 5V
UM232R © FTDI 2008
TXD
1
1
2
3
24
GND
21
VCC
20
RST#
17
PU1
16
PU2
15
VCC
14
USB
J1
TXD
RXD
RTS# 3
RXD
5
GND
7
FTDI
CTS#
FT232RL
RTS#
MCU
CTS#
10
2
J2
12
1
13
Figure 7.2 Self-Powered Configuration
Figure 7.2 illustrates the UM232R in a typical USB self-powered configuration. In this case the link on
jumper J2 is removed, and an external supply is connected to the module VCC pins. Figure 7.2 illustrates a
self-powered design which has a 4.0V – 5V supply.
A USB Self-Powered device gets its power from its own power supply and does not draw current from the
USB bus. The basic rules for USB Self-powered devices are as follows:
i) A Self-Powered device should not force current down the USB bus when the USB Host or Hub
Controller us powered down.
ii) A Self-Powered Device can use as much current as it likes during normal operation and USB suspend
as it has its own power supply.
iii) A Self-Powered Device can be used with any USB Host and both Bus and Self-Powered USB Hub. In
this case the power descriptor in the internal EEPROM should be programmed to a value of zero (selfpowered).
In order to meet requirement (i) the USB Power is used to control the RESET# Pin of the FT232R device.
When the USB Host or Hub is powered up the internal 1.5kΩ resistor on USBDP is pulled up to 3.3V, thus
identifying the devices as a full speed device to USB. When the USB Host or Hub Power is off, RESET# will
go low and the device will be held in reset. As RESET# is low, the internal 1.5kΩ resistor will not be pulled
up to 3.3V, so no current will be forced down USBDP via the 1.5kΩ pull-up resistor when the host or hub is
powered down.
To do this pin 14 (USB) is connected to PU2 and PU1 is connected to RST#. Failure to do this may cause
some USB host or hub controllers to power up erratically.
Copyright © Future Technology Devices International Limited
20
UM232R USB - Serial UART Development Module Datasheet
Version 1.3
Document No.: FT_000051
Clearance No.: FTDI# 125
Note: When the FT232R is in reset, the UART interface pins all go tristate. These pins have internal 200kΩ
pull-up resistors to VCCIO, so they will gently pull high unless driven by some external logic.
Figure 7.2 is also an example of interfacing the FT232R to a Microcontroller (MCU) UART interface. This
example uses TXD and RXD for transmission and reception of data and RTS# / CTS# hardware
handshaking.
Optionally, RI# can be connected to another I/O pin on the MCU and could be used to wake up the USB
host controller from suspend mode. One of the CBUS pins could be configured as a 6/12/24/48 MHz clock
output which can be used to clock the MCU. If the MCU is handling power management functions, then a
CBUS pin can be configured as PWREN# and should also be connected to an I/O pin of the MCU.
7.3 USB Bus Powered with Power Switching Configuration
P-Channel Power
MOSFET
s
d
UM232R © FTDI 2008
TXD
1
1
2
0.1uF
Soft
Start
Circuit
J1
TXD
RXD
1K
RTS# 3
RXD
5
GND
7
FTDI
FT232RL
RTS#
CTS#
0.1uF
g
24
3
MCU
CTS#
18 CB3
(PWREN#)
10
2
1
J2
12
14
USB
13
Figure 7.3 Bus Powered with Power Switching Configuration
USB Bus Powered circuits need to be able to power down in USB
工商网监
湘ICP备2023018690号
