Copyright © 2010 Future Technology Devices International Limited 1
Document No.: FT_000052
FT245R USB FIFO IC Datasheet Version 2.13
Clearance No.: FTDI# 39
Future Technology
Devices International Ltd.
FT245R USB FIFO IC
The FT245R is a USB to parallel FIFO
interface with the following advanced
features:
Single chip USB to parallel FIFO bidirectional
data transfer interface.
Entire USB protocol handled on the chip. No
USB specific firmware programming required.
Fully integrated 1024 bit EEPROM storing
device descriptors and FIFO I/O configuration.
Fully integrated USB termination resistors.
Fully integrated clock generation with no
external crystal required.
Data transfer rates up to 1Mbyte / second.
128 byte receive buffer and 256 byte transmit
buffer utilising buffer smoothing technology to
allow for high data throughput.
FTDI’s royalty-free Virtual Com Port (VCP) and
Direct (D2XX) drivers eliminate the
requirement for USB driver development in
most cases.
Unique USB FTDIChip-ID™ feature.
Configurable FIFO interface I/O pins.
Synchronous and asynchronous bit bang
interface options.
Device supplied pre-programmed with unique USB
serial number.
Supports bus powered, self powered and high-power
bus powered USB configurations.
Integrated +3.3V level converter for USB I/O.
Integrated level converter on FIFO interface for
interfacing to external logic running at between
+1.8V and +5V.
True 5V/3.3V/2.8V/1.8V CMOS drive output and TTL
input.
Configurable I/O pin output drive strength.
Integrated power-on-reset circuit.
Fully integrated AVCC supply filtering - no external
filtering required.
+3.3V (using external oscillator) to +5.25V (using
internal oscillator) Single Supply Operation.
Low operating and USB suspend current.
Low USB bandwidth consumption.
UHCI/OHCI/EHCI host controller compatible.
USB 2.0 Full Speed compatible.
-40°C to 85°C extended operating temperature
range.
Available in compact Pb-free 28 Pin SSOP and QFN-
32 packages (both RoHS compliant).
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 © 2010 Future Technology Devices International Limited 2
Document No.: FT_000052
FT245R USB FIFO IC Datasheet Version 2.13
Clearance No.: FTDI# 39
1 Typical Applications
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 and Writers
Set Top Box PC - USB interface
USB Digital Camera Interface
USB Hardware Modems
USB Wireless Modems
USB Bar Code Readers
USB Software and Hardware Encryption
Dongles
1.1 Driver Support
Royalty free VIRTUAL COM PORT
(VCP) DRIVERS for...
Windows 7 32,64-bit
Windows XP and XP 64-bit
Windows Vista and Vista 64-bit
Windows XP Embedded
Windows 98, 98SE, ME, 2000, Server 2003, XP
and Server 2008
Windows CE 4.2, 5.0 and 6.0
Mac OS 8/9, OS-X
Linux 2.4 and greater
Royalty free D2XX Direct Drivers
(USB Drivers + DLL S/W Interface)
Windows 7 32,64-bit
Windows XP and XP 64-bit
Windows Vista and Vista 64-bit
Windows XP Embedded
Windows 98, 98SE, ME, 2000, Server 2003, XP
and Server 2008
Windows CE 4.2, 5.0 and 6.0
Linux 2.4 and greater
The drivers listed above are all available to download for free from FTDI website (www.ftdichip.com).
Various 3rd party drivers are also available for other operating systems - see FTDI website
(www.ftdichip.com) for details. For driver installation, please refer to the application note AN232B-10.
For driver installation, please refer to http://www.ftdichip.com/Documents/InstallGuides.htm
1.2 Part Numbers
Package
32 Pin QFN
28 Pin SSOP
Note: Packaging codes for xxx is:
-Reel: Taped and Reel, (SSOP is 2,000pcs per reel, QFN is 6,000pcs per reel).
- Tube: Tube packing, 47pcs per tube (SSOP only)
- Tray: Tray packing, 490pcs per tray (QFN only)
For example: FT245RQ-Reel is 6,000pcs taped and reel packing
Copyright © 2010 Future Technology Devices International Limited 3
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FT245R USB FIFO IC Datasheet Version 2.13
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1.3 USB Compliant
The FT245R is fully compliant with the USB 2.0 specification and has been given the USB-IF Test-ID (TID)
40680005 (Rev B) and 40770019 (Rev C).
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2 FT245R Block Diagram
Clock
Multiplier
Serial Interface
Engine
( SIE )
USB
Protocol Engine
3.3 Volt
LDO
Regulator
USB
Transceiver
with
Integrated
Series
Resistors
and 1.5K
Pull-up
USB DPLL
Internal
12MHz
Oscillator
48MHz
OCSI
(optional)
OSCO
(optional)
USBDP
USBDM
3V3OUT
VCC
D0
D1
D2
D3
D4
D5
D6
D7
RD#
RXF#
TXE#
RESET#
TEST
GND
RESET
GENERATOR
3V3OUT
WR
FIFO RX Buffer
128 bytes
FIFO TX Buffer
256 bytes
Internal
EEPROM
To USB Transceiver Cell
PWREN#
To USB
Transceiver
Cell
VCCIO
FIFO Controller
with
Programmable
High Drive
Figure 2.1 FT245R Block Diagram
For a description of each function please refer to Section 4.
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Table of Contents
1 Typical Applications ........................................................................ 2
1.1 Driver Support .................................................................................... 2
1.2 Part Numbers...................................................................................... 2
1.3 USB Compliant .................................................................................... 3
2 FT245R Block Diagram .................................................................... 4
3 Device Pin Out and Signal Description ............................................ 7
3.1 28-LD SSOP Package .......................................................................... 7
3.2 SSOP Package Pin Out Description ...................................................... 7
3.3 QFN-32 Package ............................................................................... 10
3.4 QFN-32 Package Signal Description .................................................. 10
3.5 FT245R FIFO READ Timing Diagrams ................................................ 13
3.6 FT245R FIFO WRITE Timing Diagrams .............................................. 14
4 Function Description ..................................................................... 15
4.1 Key Features ..................................................................................... 15
4.2 Functional Block Descriptions ........................................................... 16
5 Devices Characteristics and Ratings .............................................. 17
5.1 Absolute Maximum Ratings............................................................... 17
5.2 DC Characteristics............................................................................. 18
5.3 EEPROM Reliability Characteristics ................................................... 21
5.4 Internal Clock Characteristics ........................................................... 21
5.5 Thermal Characteristics .................................................................... 22
6 USB Power Configurations ............................................................ 23
6.1 USB Bus Powered Configuration ...................................................... 23
6.2 Self Powered Configuration .............................................................. 24
6.3 USB Bus Powered with Power Switching Configuration .................... 25
6.4 USB Bus Powered with Selectable External Logic Supply .................. 26
7 Application Examples .................................................................... 27
7.1 USB to MCU FIFO Interface ............................................................... 27
7.2 Using the External Oscillator ............................................................ 28
8 Internal EEPROM Configuration .................................................... 29
9 Package Parameters ..................................................................... 30
9.1 SSOP-28 Package Dimensions .......................................................... 30
9.2 QFN-32 Package Dimensions ............................................................ 31
9.3 QFN-32 Package Typical Pad Layout ................................................. 32
9.4 QFN-32 Package Typical Solder Paste Diagram ................................. 32
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9.5 Solder Reflow Profile ........................................................................ 33
10 Alternative Parts ........................................................................ 34
11 Contact Information ................................................................... 35
Appendix A - References ............................................................................ 36
Appendix B - List of Figures and Tables ..................................................... 37
Appendix C - Revision History .................................................................... 39
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3 Device Pin Out and Signal Description
3.1 28-LD SSOP Package
Figure 3.1 SSOP Package Pin Out and Schematic Symbol
3.2 SSOP Package Pin Out Description
Note: The convention used throughout this document for active low signals is the signal name followed by
a #
Pin No.
Name
Type
Description
15
USBDP
I/O
USB Data Signal Plus, incorporating internal series resistor and 1.5kΩ pull up
resistor to 3.3V.
16
USBDM
I/O
USB Data Signal Minus, incorporating internal series resistor.
Table 3.1 USB Interface Group
FT245RL
A
G
N
D
G
N
D
G
N
D
G
N
D
T
E
S
T
25 718 21 26
3V3OUT
VCCIO
4
17
NC
RESET#
NC
24
19
8
D0
D1
D2
D3
D4
D5
D6
D7
1
5
3
11
2
9
10
6
RXF#
WR
RD#
TXE#
23
22
13
14
20
16
15 USBDP
USBDM
VCC
OSCI
27
OSCO
28
PWREN# 12
USBDP
USBDM
3V3OUT
GND
RESET#
VCC
GND
NC
AGND
TEST
OSCI
OSCO
TXE#
RXF#
D0
D2
D1
D4
VCCIO
D7
GND
NC
D5
D6
D3
PWREN#
RD#
WR
FT245RL
YYXX-A
1
14 15
28
FTDI
XXXXXXXXXXXX
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Pin No.
Name
Type
Description
4
VCCIO
PWR
+1.8V to +5.25V supply to the FIFO Interface group pins (1...3, 5, 6, 9...14, 22,
23). In USB bus powered designs connect this pin to 3V3OUT pin to drive out at
+3.3V levels, or connect to VCC to drive out at 5V CMOS level. This pin can also
be supplied with an external +1.8V to +2.8V supply in order to drive outputs 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.
7, 18,
21
GND
PWR
Device ground supply pins
17
3V3OUT
Output
+3.3V output from integrated LDO regulator. This pin should be decoupled to
ground using a 100nF capacitor. The main use 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 VCCIO pin.
20
VCC
PWR
+3.3V to +5.25V supply to the device core. (see Note 1)
25
AGND
PWR
Device analogue ground supply for internal clock multiplier
Table 3.2 Power and Ground Group
Pin No.
Name
Type
Description
8, 24
NC
NC
No internal connection
19
RESET#
Input
Active low reset pin. This can be used by an external device to reset the
FT245R. If not required can be left unconnected, or pulled up to VCC.
26
TEST
Input
Puts the device into IC test mode. Must be tied to GND for normal
operation, otherwise the device will appear to fail.
27
OSCI
Input
Input 12MHz Oscillator Cell. Optional – Can be left unconnected for
normal operation. (see Note 2)
28
OSCO
Output
Output from 12MHZ Oscillator Cell. Optional – Can be left unconnected
for normal operation if internal Oscillator is used. (see Note 2)
Table 3.3 Miscellaneous Signal Group
Pin No.
Name
Type
Description
1
D0
I/O
FIFO Data Bus Bit 0
2
D4
I/O
FIFO Data Bus Bit 4
3
D2
I/O
FIFO Data Bus Bit 2
5
D1
I/O
FIFO Data Bus Bit 1
6
D7
I/O
FIFO Data Bus Bit 7
9
D5
I/O
FIFO Data Bus Bit 5
10
D6
I/O
FIFO Data Bus Bit 6
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Pin No.
Name
Type
Description
11
D3
I/O
FIFO Data Bus Bit 3
12
PWREN#
Output
Goes low after the device is configured by USB, then high during USB suspend.
Can be used to control power to external logic P-Channel logic level MOSFET
switch. Enable the interface pull-down option when using the PWREN# pin in this
way. Should be pulled to VCCIO with 10kΩ resistor.
13
RD#
Input
Enables the current FIFO data byte on D0...D7 when low. Fetched the next FIFO
data byte (if available) from the receive FIFO buffer when RD# goes from high to
low. See Section 3.5 for timing diagram.
14
WR
Input
Writes the data byte on the D0...D7 pins into the transmit FIFO buffer when WR
goes from high to low. See Section 3.6 for timing diagram.
22
TXE#
Output
When high, do not write data into the FIFO. When low, data can be written into
the FIFO by strobing WR high, then low. During reset this signal pin is tri-state.
See Section 3.6 for timing diagram.
23
RXF
Output
When high, do not read data from the FIFO. When low, there is data available in
the FIFO which can be read by strobing RD# low, then high again. During reset
this signal pin is tri-state. See Section 3.5 for timing diagram.
If the Remote Wakeup option is enabled in the internal EEPROM, during USB
suspend mode (PWREN# = 1) RXF# becomes an input. This can be used to wake
up the USB host from suspend mode by strobing this pin low for a minimum of
20ms which will cause the device to request a resume on the USB bus.
Table 3.4 FIFO Interface Group (see note 3)
Notes:
1. The minimum operating voltage VCC must be +4.0V (could use VBUS=+5V) when using the
internal clock generator. Operation at +3.3V is possible using an external crystal oscillator.
2. For details on how to use an external crystal, ceramic resonator, or oscillator with the FT245R,
please refer Section 7.2
3. When used in Input Mode, the input 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.
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3.3 QFN-32 Package
D7
Figure 3.2 QFN-32 Package Pin Out and schematic symbol
3.4 QFN-32 Package Signal Description
Pin No.
Name
Type
Description
14
USBDP
I/O
USB Data Signal Plus, incorporating internal series resistor and 1.5kΩ pull up resistor
to +3.3V.
15
USBDM
I/O
USB Data Signal Minus, incorporating internal series resistor.
Table 3.5 USB Interface Group
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Pin No.
Name
Type
Description
1
VCCIO
PWR
+1.8V to +5.25V supply for the FIFO Interface group pins (2, 3, 6,7,8,9,10 11, 21,
22, 30,31,32). In USB bus powered designs connect this pin to 3V3OUT to drive out
at +3.3V levels, or connect to VCC to drive out at +5V CMOS level. This pin can also
be supplied with an external +1.8V to +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.
4, 17,
20
GND
PWR
Device ground supply pins.
16
3V3OUT
Output
+3.3V output from integrated LDO regulator. This pin should be decoupled to
ground using a 100nF capacitor. The purpose of this output 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 VCCIO pin.
19
VCC
PWR
+3.3V to +5.25V supply to the device core. (see Note 1).
24
AGND
PWR
Device analogue ground supply for internal clock multiplier.
Table 3.6 Power and Ground Group
Pin No.
Name
Type
Description
5, 12,
13, 23,
25, 29
NC
NC
No internal connection. Do not connect.
18
RESET#
Input
Active low reset. Can be used by an external device to reset the FT245R. If
not required can be left unconnected, or pulled up to VCC.
26
TEST
Input
Puts the device into IC test mode. Must be tied to GND for normal
operation, otherwise the device will appear to fail.
27
OSCI
Input
Input 12MHz Oscillator Cell. Optional – Can be left unconnected for normal
operation. (see Note 2).
28
OSCO
Output
Output from 12MHZ Oscillator Cell. Optional – Can be left unconnected for
normal operation if internal Oscillator is used. (see Note 2).
Table 3.7 Miscellaneous Signal Group
Pin
No.
Name
Type
Description
30
D0
I/O
FIFO Data Bus Bit 0
31
D4
I/O
FIFO Data Bus Bit 4
32
D2
I/O
FIFO Data Bus Bit 2
2
D1
I/O
FIFO Data Bus Bit 1
3
D7
I/O
FIFO Data Bus Bit 7
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Pin
No.
Name
Type
Description
6
D5
I/O
FIFO Data Bus Bit 5
7
D6
I/O
FIFO Data Bus Bit 6
8
D3
I/O
FIFO Data Bus Bit 3
9
PWREN#
Output
Goes low after the device is configured by USB, then high during USB
suspend. Can be used to control power to external logic P-Channel logic
level MOSFET switch. Enable the interface pull-down option when using the
PWREN# pin in this way. Should be pulled to VCCIO with 10kΩ resistors.
10
RD#
Input
Enables the current FIFO data byte from D0…D7 when low. Fetched the next
FIFO data byte (if available) from the receive FIFO buffer when RD# goes
from high to low. See Section 3.5 for timing diagram.
11
WR
Input
Writes the data from byte from D0...D7 pins into the transmit FIFO buffer
when WR goes from high to low. See section 3.6 for timing diagram.
21
TXE#
Output
When high, do not write data into the FIFO. When low, data can be written
into the FIFO by strobing WR high, then low. During reset this signal pin is
tri-state. See Section 3.6 for timing diagram.
22
RXF#
Output
When high, do not read data from the FIFO. When low, there is data
available in the FIFO which can be read by strobing RD# low, then high
again. During reset this signal pin is tri-state. See Section 3.5 for timing
diagram.
If the Remote Wakeup option is enabled in the internal EEPROM, during USB
suspend mode (PWREN# = 1) RXF# becomes an input. This can be used to
wake up the USB host from suspend mode by strobing this pin low for a
minimum of 20ms which will cause the device to request a resume on the
USB bus.
Table 3.8 FIFO Interface Group (see note 3)
Notes:
1. The minimum operating voltage VCC must be +4.0V (could use VBUS=+5V) when
using the internal clock generator. Operation at +3.3V is possible using an external
crystal oscillator.
2. For details on how to use an external crystal, ceramic resonator, or oscillator with the FT245R,
please refer to Section 7.2
3. When used in Input Mode, the input 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.
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3.5 FT245R FIFO READ Timing Diagrams
Figure 3.3 FIFO Read Cycle
Time
Description
Minimum
Maximum
Unit
T1
RD# Active Pulse Width
50
-
ns
T2
RD# to RD# Pre-Charge Time
50 + T6
-
ns
T3
RD# Active to Valid Data*
20
50
ns
T4
Valid Data Hold Time from RD#
Inactive*
0
-
ns
T5
RD# Inactive to RXF#
0
25
ns
T6
RXF# Inactive After RD Cycle
80
-
ns
Table 3.9 FIFO Read Cycle Timings
*Load = 30pF
RXF#
RD#
D[7...0]
T3
T1
T5 T6
T2
T4
Valid Data
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3.6 FT245R FIFO WRITE Timing Diagrams
Figure 3.4 FIFO Write Cycle
Time
Description
Minimum
Maximum
Unit
T7
WR Active Pulse Width
50
-
ns
T8
WR to WR Pre-Charge Time
50
-
ns
T9
Valid data setup to WR falling
edge*
20
-
ns
T10
Valid Data Hold Time from WR
Inactive*
0
-
ns
T11
WR Inactive to TXE#
5
25
ns
T12
TXE# Inactive After WR Cycle
80
-
ns
Table 3.10 FIFO Write Cycle
*Load = 30pF
Valid Data
D[7...0]
WR
TXE# T7
T12
T11
T8
T9 T10
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4 Function Description
The FT245R is a USB to parallel FIFO interface device which simplifies USB to FIFO designs and reduces
external component count by fully integrating an external EEPROM, USB termination resistors and an
integrated clock circuit which requires no external crystal, into the device. It has been designed to
operate efficiently with a USB host controller by using as little as possible of the total USB bandwidth
available.
4.1 Key Features
Functional Integration. Fully integrated EEPROM, USB termination resistors, clock generation, AVCC
filtering, power-on-reset (POR) and LDO regulator.
Asynchronous Bit Bang Mode. In asynchronous bit-bang mode, the eight FIFO 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 pre-scaler. This option will be described more fully in a separate application
note available from FTDI website (www.ftdichip.com).
Synchronous Bit Bang Mode. The FT245R supports synchronous bit bang mode. This mode differs from
asynchronous bit bang mode in that the interface pins are only read when the device is written to. This
makes it easier for the controlling program to measure the response to an output stimulus as the data
returned is synchronous to the output data. An application note, AN232R-01, available from FTDI website
(www.ftdichip.com) describes this feature.
FTDIChip-ID™. The FT245R also includes the new FTDIChip-ID™ security dongle feature. This
FTDIChip-ID™ feature allows a unique number to be burnt into each device during manufacture. This
number cannot be reprogrammed. This number is only readable over USB and forms a basis of a security
dongle which can be used to protect any customer application software being copied. This allows the
possibility of using the FT245R in a dongle 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 FT245R 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, AN232R-02,
available from FTDI website (www.ftdichip.com) describes this feature.
High Output Drive Option. The parallel FIFO interface and the four FIFO handshake 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 a greater signal drive strength to be interfaced to the FT245R. This option is
configured in the internal EEPROM.
Programmable FIFO RX Buffer Timeout. The FIFO RX buffer timeout is used to flush remaining data
from the receive buffer. This timeout defaults to 16ms, but is programmable over USB in 1ms increments
from 2ms to 255ms, thus allowing the device to be optimised for protocols that require fast response
times from short data packets.
Wake Up Function. If USB is in suspend mode, and remote wake up has been enabled in the internal
EEPROM (it is enabled by default), the RXF# pin becomes an input. Strobing this pin low for a minimum
of 20ms will cause the FT245R to request a resume from suspend on the USB bus. Normally this can be
used to wake up the host PC from suspend.
The FT245R is capable of operating at a voltage supply between +3.3V and +5V with a nominal
operational mode current of 15mA and a nominal USB suspend mode current of 70µA. This allows greater
margin for peripheral designs to meet the USB suspend mode current limit of 2.5mA. An integrated level
converter within the FIFO interface allows the FT245R to interface to FIFO logic running at +1.8V, 2.5V,
+3.3V or +5V.
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4.2 Functional Block Descriptions
The following paragraphs detail each function within the FT245R. Please refer to the block
diagram shown in Figure 2.1.
Internal EEPROM. The internal EEPROM in the FT245R is used to store USB Vendor ID (VID), Product ID
(PID), device serial number, product description string and various other USB configuration descriptors.
The FT245R is supplied with the internal EEPROM pre-programmed as described in Section 8. A user area
of the internal EEPROM is available to system designers to allow storing additional data. The internal
EEPROM descriptors can be programmed in circuit, over USB without any additional voltage requirement.
It can be programmed using the FTDI utility software called MPROG and FT_PROG, which can be
downloaded from FTDI Utilities on the FTDI website (www.ftdichip.com).
+3.3V LDO Regulator. The +3.3V LDO regulator generates the +3.3V reference voltage for driving the
USB transceiver cell output buffers. It requires an external decoupling capacitor to be attached to the
3V3OUT regulator output pin. It also provides +3.3V power to the 1.5kΩ internal pull up resistor on
USBDP. The main function of the LDO is to power the USB Transceiver and the Reset Generator Cells
rather than to power external logic. However, it can be used to supply external circuitry requiring a
+3.3V nominal supply with a maximum current of 50mA.
USB Transceiver. The USB Transceiver Cell provides the USB 1.1 / USB 2.0 full-speed physical interface
to the USB cable. The output drivers provide +3.3V level slew rate control signalling, whilst a differential
input receiver and two single ended input receivers provide USB data in, Single-Ended-0 (SE0) and USB
reset detection conditions respectfully. This function also incorporates the internal USB series termination
resistors on the USB data lines and a 1.5kΩ pull up resistor on USBDP.
USB DPLL. The USB DPLL cell locks on to the incoming NRZI USB data and generates recovered clock
and data signals for the Serial Interface Engine (SIE) block.
Internal 12MHz Oscillator. The Internal 12MHz Oscillator cell generates a 12MHz reference clock. This
provides an input to the x4 Clock Multiplier function. The 12MHz Oscillator is also used as the reference
clock for the SIE, USB Protocol Engine and FIFO controller blocks.
Clock Multiplier / Divider. The Clock Multiplier / Divider takes the 12MHz input from the Internal
Oscillator function and generates the 48MHz. The 48Mz clock reference is used by the USB DPLL and the
Baud Rate Generator blocks.
Serial Interface Engine (SIE). The Serial Interface Engine (SIE) block performs the parallel to serial
and serial to parallel conversion of the USB data. In accordance with the USB 2.0 specification, it
performs bit stuffing/un-stuffing and CRC5/CRC16 generation. It also checks the CRC on the USB data
stream.
USB Protocol Engine. The USB Protocol Engine manages the data stream from the device USB control
endpoint. It handles the low level USB protocol requests generated by the USB host controller and the
commands for controlling the functional parameters of the FIFO in accordance with the USB 2.0
specification Section 9.
FIFO RX Buffer (128 bytes). Data sent from the USB host controller to the FIFO via the USB data OUT
endpoint is stored in the FIFO RX (receive) buffer and is removed from the buffer by reading the contents
of the FIFO using the RD# pin. (Rx relative to the USB interface).
FIFO TX Buffer (256 bytes). Data written into the FIFO using the WR pin is stored in the FIFO TX
(transmit) Buffer. The USB host controller removes data from the FIFO TX Buffer by sending a USB
request for data from the device data IN endpoint. (Tx relative to the USB interface).
FIFO Controller with Programmable High Drive. The FIFO Controller handles the transfer of data
between the FIFO RX, the FIFO TX buffers and the external FIFO interface pins (D0 - D7).
Additionally, the FIFO signals have a configurable high drive strength capability which is configurable in
the EEPROM.
RESET Generator. The integrated Reset Generator Cell provides a reliable power-on reset to the device
internal circuitry at power up. The RESET# input pin allows an external device to reset the FT245R.
RESET# can be tied to VCC or left unconnected if not being used.
Copyright © 2010 Future Technology Devices International Limited 17
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FT245R USB FIFO IC Datasheet Version 2.13
Clearance No.: FTDI# 39
5 Devices Characteristics and Ratings
5.1 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
Units
Storage Temperature
-65 to 150
°C
Floor Life (Out of Bag) At Factory Ambient
(30°C / 60% Relative Humidity)
168
(IPC/JEDEC J-STD-033A
MSL Level 3 Compliant)*
Hours
Ambient Temperature (Power Applied)
-40 to 85
°C
MTTF FT245RL
6607685
hours
MTTF FT245RQ
4464815
hours
VCC Supply Voltage
-0.5 to +6.00
V
DC Input Voltage – USBDP and USBDM
-0.5 to +3.8
V
DC Input Voltage – High Impedance
Bidirectionals
-0.5 to + (VCC +0.5)
V
DC Input Voltage – All Other Inputs
-0.5 to + (VCC +0.5)
V
DC Output Current – Outputs
24
mA
Power Dissipation (VCC = 5.25V)
500
mW
Table 5.1 Absolute Maximum Ratings
* 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.
Copyright © 2010 Future Technology Devices International Limited 18
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FT245R USB FIFO IC Datasheet Version 2.13
Clearance No.: FTDI# 39
5.2 DC Characteristics
DC Characteristics (Ambient Temperature = -40°C to +85°C)
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
VCC1
VCC Operating
Supply Voltage
4.0
---
5.25
V
Using Internal
Oscillator
VCC1
VCC Operating
Supply Voltage
3.3
---
5.25
V
Using External
Crystal
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
μA
USB Suspend
3V3
3.3v regulator
output
3.0
3.3
3.6
V
Table 5.2 Operating Voltage and Current
Parameter
Description
Minimum
Typical
Maximum
Units
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
1.0
1.2
1.5
V
**
VHys
Input Switching
Hysteresis
20
25
30
mV
**
Table 5.3 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 5.4 UART and CBUS I/O Pin Characteristics (VCCIO = +3.3V, Standard Drive Level)
Copyright © 2010 Future Technology Devices International Limited 19
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FT245R USB FIFO IC Datasheet Version 2.13
Clearance No.: FTDI# 39
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
2.1
2.6
2.8
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 5.5 UART and CBUS I/O Pin Characteristics (VCCIO = +2.8V, Standard Drive Level)
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
1.32
1.62
1.8
V
I source = 0.2mA
Vol
Output Voltage Low
0.06
0.1
0.18
V
I sink = 0.5mA
Vin
Input Switching
Threshold
1.0
1.2
1.5
V
**
VHys
Input Switching
Hysteresis
20
25
30
mV
**
Table 5.6 UART and CBUS I/O Pin Characteristics (VCCIO = +1.8V, 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
1.0
1.2
1.5
V
**
VHys
Input Switching
Hysteresis
20
25
30
mV
**
Table 5.7 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 5.8 UART and CBUS I/O Pin Characteristics (VCCIO = +3.3V, High Drive Level)
Copyright © 2010 Future Technology Devices International Limited 20
Document No.: FT_000052
FT245R USB FIFO IC Datasheet Version 2.13
Clearance No.: FTDI# 39
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
2.1
2.6
2.8
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 5.9 UART and CBUS I/O Pin Characteristics (VCCIO = +2.8V, High Drive Level)
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Voh
Output Voltage High
1.35
1.67
1.8
V
I source = 0.4mA
Vol
Output Voltage Low
0.12
0.18
0.35
V
I sink = 3mA
Vin
Input Switching
Threshold
1.0
1.2
1.5
V
**
VHys
Input Switching
Hysteresis
20
25
30
mV
**
Table 5.10 UART and CBUS I/O Pin Characteristics (VCCIO = +1.8V, High Drive Level)
** Only input pins have an internal 200KΩ pull-up resistor to VCCIO
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
Vin
Input Switching
Threshold
1.3
1.6
1.9
V
VHys
Input Switching
Hysteresis
50
55
60
mV
Table 5.11 RESET# and TEST Pin Characteristics
Copyright © 2010 Future Technology Devices International Limited 21
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FT245R USB FIFO IC Datasheet Version 2.13
Clearance No.: FTDI# 39
Parameter
Description
Minimum
Typical
Maximum
Units
Conditions
UVoh
I/O Pins Static
Output (High)
2.8
3.6
V
RI = 1.5kΩ to
3V3OUT (D+) RI =
15KΩ to GND (D-)
UVol
I/O Pins Static
Output (Low)
0
0.3
V
RI = 1.5kΩ to
3V3OUT (D+) RI =
15kΩ to GND (D-)
UVse
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
See Note 1
Table 5.12 USB I/O Pin (USBDP, USBDM) Characteristics
5.3 EEPROM Reliability Characteristics
The internal 1024 Bit EEPROM has the following reliability characteristics:
Parameter
Value
Units
Data Retention
10
Years
Write
10,000
Cycles
Read
Unlimited
Cycles
Table 5.13 EEPROM Characteristics
5.4 Internal Clock Characteristics
The internal Clock Oscillator has the following characteristics:
Parameter
Value
Unit
Minimum
Typical
Maximum
Frequency of Operation
(see Note 1)
11.98
12.00
12.02
MHz
Clock Period
83.19
83.33
83.47
ns
Duty Cycle
45
50
55
%
Table 5.14 Internal Clock Characteristics
Note 1: Equivalent to +/-1667ppm
Copyright © 2010 Future Technology Devices International Limited 22
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FT245R USB FIFO IC Datasheet Version 2.13
Clearance No.: FTDI# 39
Parameter
Description
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
Table 5.15 OSCI, OSCO Pin Characteristics – see Note 1
Note1: When supplied, the FT232R is configured to use its internal clock oscillator. These characteristics
only apply when an external oscillator or crystal is used.
5.5 Thermal Characteristics
The FT245RL package has the following thermal characteristics:
Parameter
Value
Units
Conditions
Theta JA (ƟJA)
55.82
°C/W
Still air
Theta JC (ƟJC)
24.04
°C/W
Table 5.16 FT245RL Thermal Characteristics
The FT245RQ package has the following thermal characteristics:
Parameter
Value
Units
Conditions
Theta JA (ƟJA)
31.49
°C/W
Still air, center pad soldered to PCB, 9 vias to another plane
Theta JA (ƟJA)
62.31
°C/W
Still air, center pad unsoldered
Theta JC (ƟJC)
°C/W
Table 5.17 FT245RQ Thermal Characteristics
Copyright © 2010 Future Technology Devices International Limited 23
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FT245R USB FIFO IC Datasheet Version 2.13
Clearance No.: FTDI# 39
6 USB Power Configurations
The following sections illustrate possible USB power configurations for the FT245R. The illustrations have
omitted pin numbers for ease of understanding since the pins differ between the FT245RL and FT245RQ
package options.
All USB power configurations illustrated apply to both package options for the FT245R device. Please refer
to Section 3 for the package option pin-out and signal descriptions.
6.1 USB Bus Powered Configuration
FT245R
GND
GND
100nF
VCC
USBDM
USBDP
VCCIO
NC
RESET#
NC
OSCI
OSCO
3V3OUT
A
G
N
D
G
N
D
G
N
D
G
N
D
T
E
S
T
Vcc
1
2
3
4
GND
SHIELD
GND
VCC
100nF 4.7uF +
510nF
Ferrite
Bead D0
D1
D2
D3
D4
D5
D6
D7
RXF#
TXE#
RD#
WR
PWREN#
Vcc
10K
Figure 6.1 Bus Powered Configuration
Figure 6.1 illustrates the FT245R in a typical USB bus powered design configuration. 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 should draw no more current than 100mA.
ii) In USB Suspend mode the device should draw no more than 2.5mA.
iii) A bus powered high power USB device (one that draws more than 100mA) should use the
PWREN# to keep the current below 100mA on plug-in and 2.5mA 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 than 500mA from the USB bus.
The power descriptors in the internal EEPROM of the FT245R should be programmed to match the current
drawn by the device.
A ferrite bead is connected in series with the USB power supply to reduce EMI noise from the FT245R and
associated circuitry being radiated down the USB cable to the USB host. The value of the Ferrite Bead
depends on the total current drawn by the application. A suitable range of Ferrite Beads is available from
Steward (www.steward.com), for example Steward Part # MI0805K400R-10.
Note: If using PWREN#, the pin should be pulled to VCCIO using a 10kΩ resistor.
Copyright © 2010 Future Technology Devices International Limited 24
Document No.: FT_000052
FT245R USB FIFO IC Datasheet Version 2.13
Clearance No.: FTDI# 39
6.2 Self Powered Configuration
Figure 6.2 Self Powered Configuration
Figure 6.2 illustrates the FT245R in a typical USB self powered configuration. A USB self powered device
gets its power from its own power supply, VCC, 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 is powered down.
ii) A self powered device can use as much current as it needs 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, a bus powered USB hub or a self
powered USB hub.
The power descriptor in the internal EEPROM of the FT245R should be programmed to a value of zero
(self powered).
In order to comply with the first requirement above, the USB bus power (pin 1) is used to control the
RESET# pin of the FT245R device. When the USB host or hub is powered up an internal 1.5kΩ resistor
on USBDP is pulled up to +3.3V (generated using the 4K7 and 10k resistor network), thus identifying the
device as a full speed device to the USB host or hub. When the USB host or hub is powered off, RESET#
will be low and the FT245R is held in reset. Since RESET# is low, the internal 1.5kΩ resistor is not pulled
up to any power supply (hub or host is powered down), so no current flows down USBDP via the 1.5kΩ
pull-up resistor. Failure to do this may cause some USB host or hub controllers to power up erratically.
Error! Reference source not found. illustrates a self powered design which has a +4V to +5.25V
supply.
Note:
1. When the FT232R is in reset, the UART interface I/O pins are tri-stated. Input pins have internal
200kΩ pull-up resistors to VCCIO, so they will gently pull high unless driven by some external
logic.
2. When using internal FT232R oscillator the VCC supply voltage range must be +4.0V to 5.25V.
3. When using external oscillator the VCC supply voltage range must be +3.3V to 5.25V
Any design which interfaces to +3.3 V or +1.8V would be having a +3.3V or +1.8V supply to
VCCIO.
Copyright © 2010 Future Technology Devices International Limited 25
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FT245R USB FIFO IC Datasheet Version 2.13
Clearance No.: FTDI# 39
6.3 USB Bus Powered with Power Switching Configuration
FT245R
A
G
N
D
G
N
D
G
N
D
G
N
D
T
E
S
T
100nF 3V3OUT
VCCIO
NC
RESET#
NC
+
100nF
10nF
5V VCC
D0
D1
D2
D3
D4
D5
D6
D7
TXE#
WR#
RD#
RXF#
USBDP
USBDM
VCC
1
2
3
4
5
OSCI
OSCO
PWREN#
Ferrite
Bead
+
4.7uF
SHIELD
GND
GND
GND
GND
0.1uF 0.1uF
1k
Soft Start
Circuit
d
g
sSwitched 5V Power
to External Logic
5V VCC
P-Channel Power
MOSFET
10K
5V VCC
Figure 6.3 Bus Powered with Power Switching Configuration
A requirement of USB bus powered applications, is when in USB suspend mode the application draws a
total current of less than 2.5mA. This requirement includes external logic. Some external logic has the
ability to power itself down into a low current state by monitoring the PWREN# signal. For external logic
that cannot power itself down in this way, the FT245R provides a simple but effective method of turning
off power during the USB suspend mode.
Figure 6.3 shows an example of using a discrete P-Channel MOSFET to control the power to external
logic. A suitable device to do this is an International Rectifier (www.irf.com) IRLML6402, or equivalent. It
is recommended that a “soft start” circuit consisting of a 1kΩ series resistor and a 0.1μF capacitor is used
to limit the current surge when the MOSFET turns on. Without the soft start circuit it is possible that the
transient power surge, caused when the MOSFET switches on, will reset the FT245R or the USB host/hub
controller. The soft start circuit example shown in Figure 6.3 powers up with a slew rate of
approximaely12.5V/ms. Thus supply voltage to external logic transitions from GND to +5V in
approximately 400 microseconds.
As an alternative to the MOSFET, a dedicated power switch IC with inbuilt “soft-start” can be used. A
suitable power switch IC for such an application is the Micrel (www.micrel.com) MIC2025-2BM or
equivalent.
With power switching controlled designs the following should be noted:
i) The external logic to which the power is being switched should have its own reset circuitry to
automatically reset the logic when power is re-applied when moving out of suspend mode.
ii) Set the Pull-down on Suspend option in the internal FT245R EEPROM.
iii) The PWREN# pin should be used to switch the power to the external circuitry.
iv) For USB high-power bus powered applications (one that consumes greater than 100mA, and up
to 500mA of current from the USB bus), the power consumption of the application must be set in
the Max Power field in the internal FT245R EEPROM. A high-power bus powered application uses
the descriptor in the internal FT245R EEPROM to inform the system of its power requirements.
Copyright © 2010 Future Technology Devices International Limited 26
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FT245R USB FIFO IC Datasheet Version 2.13
Clearance No.: FTDI# 39
v) PWREN# gets its VCC from VCCIO. For designs using 3V3 logic, ensure VCCIO is not powered
down using the external logic. In this case use the +3V3OUT.
6.4 USB Bus Powered with Selectable External Logic Supply
FT245R
A
G
N
D
G
N
D
G
N
D
G
N
D
T
E
S
T
100nF 3V3OUT
VCCIO
NC
RESET#
NC
10nF
D0
D1
D2
D3
D4
D5
D6
D7
TXE#
WR#
RD#
RXF#
USBDP
USBDM
VCC
1
2
3
4
5
OSCI
OSCO
PWREN#
Ferrite
Bead
+
SHIELD
GND
GND
GND
3.3V or 5V Supply
to External Logic
100nF
+
100nF
Vcc
4.7uF
GND
1
Jumper
2
3
Vcc
VCCIO
10k
VCCIO
Figure 6.4 USB Bus Powered with +3.3V or +5V External Logic Power Supply
Figure 6.4 illustrates a USB bus power application with selectable external logic supply. The external logic
can be selected between +3.3V and +5V using the jumper switch. This jumper is used to allow the
FT245R to be interfaced with a +3.3V or +5V logic devices. The VCCIO pin is either supplied with +5V
from the USB bus (jumper pins1 and 2 connected), or from the +3.3V output from the FT245R 3V3OUT
pin (jumper pins 2 and 3 connected). The supply to VCCIO is also used to supply external logic.
With bus powered applications, the following should be noted:
i) To comply with the 2.5mA current supply limit during USB suspend mode, PWREN# or
SLEEP# signals should be used to power down external logic in this mode. If this is not
possible, use the configuration shown in Section 8.
ii) The maximum current sourced from the USB bus during normal operation should not exceed
100mA, otherwise a bus powered design with power switching (Section 6.3) should be used.
Another possible configuration could use a discrete low dropout (LDO) regulator which is supplied by the
5V on the USB bus to supply between +1.8V and +2.8V to the VCCIO pin and to the external logic. In
this case VCC would be supplied with the +5V from the USB bus and the VCCIO would be supplied from
the output of the LDO regulator. This results in the FT245R I/O pins driving out at between +1.8V and
+2.8V logic levels.
For a USB bus powered application, it is important to consider the following when selecting the regulator:
i) The regulator must be capable of sustaining its output voltage with an input voltage of
+4.35V. An Low Drop Out (LDO) regulator should be selected.
ii) The quiescent current of the regulator must be low enough to meet the total current
requirement of <= 2.5mA during USB suspend mode.
A suitable series of LDO regulators that meets these requirements is the MicroChip/Telcom
(www.microchip.com) TC55 series of devices. These devices can supply up to 250mA current and have a
quiescent current of under 1μA.
Copyright © 2010 Future Technology Devices International Limited 27
Document No.: FT_000052
FT245R USB FIFO IC Datasheet Version 2.13
Clearance No.: FTDI# 39
7 Application Examples
The following sections illustrate possible applications of the FT245R. The illustrations have omitted pin
numbers for ease of understanding since the pins differ between the FT245RL and FT245RQ package
options.
7.1 USB to MCU FIFO Interface
FT245R
A
G
N
D
G
N
D
G
N
D
G
N
D
T
E
S
T
100nF
3V3OUT
VCCIO
NC
RESET#
NC
+
100nF 4.7uF
Vcc
D0
D1
D2
D3
D4
D5
D6
D7
RXF#
WR#
RD#
TXE#
USBDP
USBDM
VCC
1
2
3
4
5
OSCI
OSCO
PWREN#
Microcontroller
I/O10
I/O11
I/O12
I/O13
Ferrite
Bead
GND
GND
GND
+
GND
10nF
VCC
I/O14
I/O15
I/O16
I/O17
I/O20
I/O21
I/O22
I/O23
I/O24
Vcc
10k
SHIELD
VCC
Figure 7.1 USB to MCU FIFO Interface
A typical example of using the FT245R as a USB to Microcontroller (MCU) FIFO interface is illustrated in
Figure 7.1. This example uses two MCU I/O ports: one port (8 bits) to transfer data and the other port (4
or 5 bits) to monitor the TXE# and RXF# status bits and generate the RD# and WR strobes to the
FT245R, when required.
Using PWREN# for this function is optional.
If the Remote Wakeup option is enabled in the internal EEPROM, during USB suspend mode RXF#
becomes an input which can be used to wake up the USB host controller by strobing the pin low.
Copyright © 2010 Future Technology Devices International Limited 28
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7.2 Using the External Oscillator
The FT245R defaults to operating using its own internal oscillator. This requires that the device is
powered with VCC (min)=+4.0V. This supply voltage can be taken from the USB VBUS. Applications
which require using an external oscillator, VCC= +3.3V must do so in the following order:
1. When device powered for the very first time, it must have VCC > +4.0V. This supply is available
from the USB VBUS supply = +5.0V.
2. The EEPROM must then be programmed to enable external oscillator. This EEPROM modification
cannot be done using the FTDI programming utility, MPROG and FT_PROG. The EEPROM can
only be re-configured from a custom application. Please refer to the following applications note on
how to do this:
http://www.ftdichip.com/Documents/AppNotes/AN_100_Using_The_FT232_245R_With_External_
Osc(FT_000067).pdf
3. The FT245R can then be powered from VCC=+3.3V and an external oscillator. This can be done
using a link to switch the VCC supply.
The FT245R will fail to operate when the internal oscillator has been disabled, but no external oscillator
has been connected.
Copyright © 2010 Future Technology Devices International Limited 29
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FT245R USB FIFO IC Datasheet Version 2.13
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8 Internal EEPROM Configuration
Following a power-on reset or a USB reset the FT245R will scan its internal EEPROM and read the USB
configuration descriptors stored there. The default factory programmed values of the internal EEPROM
are shown in Table 8.1 Default Internal EEPROM Configuration.
Parameter
Value
Notes
USB Vendor ID (VID)
0403h
FTDI default VID (hex)
USB Product UD (PID)
6001h
FTDI default PID (hex)
Serial Number Enabled?
Yes
Serial Number
See Note
A unique serial number is generated and
programmed into the EEPROM during device final
test.
Pull down I/O Pins in USB
Suspend
Disabled
Enabling this option will make the device pull down
on the FIFO interface lines when in USB suspend
mode (PWREN# is high).
Manufacturer Name
FTDI
Product Description
FT245R USB FIFO
Max Bus Power Current
90mA
Power Source
Bus Powered
Device Type
FT245R
USB Version
0200
Returns USB 2.0 device description to the host.
Note: The device is a USB 2.0 Full Speed device
(12Mb/s) as opposed to a USB 2.0 High Speed
device (480Mb/s).
Remote Wake Up
Enabled
Taking RXF# low will wake up the USB host
controller from suspend in approximately 20 ms.
High Current I/Os
Disabled
Enables the high drive level on the FIFO data bus
and control I/O pins.
Load VCP Driver
Enabled
Makes the device load the VCP driver interface for
the device.
Table 8.1 Default Internal EEPROM Configuration
The internal EEPROM in the FT245R can be programmed over USB using the FTDI utility program MPROG
and FT_PROG which can be downloaded from FTDI Utilities, on the FTDI website (www.ftdichip.com).
Version 2.8a or later is required for the FT245R chip. Users who do not have their own USB Vendor ID
but who would like to use a unique Product ID in their design can apply to FTDI for a free block of unique
PIDs. Contact FTDI support for this service.
Copyright © 2010 Future Technology Devices International Limited 30
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9 Package Parameters
The FT245R is available in two different packages. The FT245RL is the SSOP-28 option and the FT245RQ
is the QFN-32 package option. The solder reflow profile for both packages is described in Section 0.
9.1 SSOP-28 Package Dimensions
Figure 9.1 SSOP-28 Package Dimensions
The FT245RL is supplied in a RoHS compliant 28 pin SSOP package. The package is lead (Pb) free and
uses a ‘green’ compound. The package is fully compliant with European Union directive 2002/95/EC.
This package is nominally 5.30mm x 10.20mm body (7.80mm x 10.20mm including pins). The pins are
on a 0.65 mm pitch. The above mechanical drawing shows the SSOP-28 package.
All dimensions are in millimetres.
The date code format is YYXX where XX = 2 digit week number, YY = 2 digit year number.
The code XXXXXXXXXXXX is the manufacturing LOT code. This only applies to devices manufactured
after April 2009.
12° Typ
0° - 8°
0.25
0.75 +/-0.20
0.09
2.00 Max
1.75
+/- 0.10
0.05 Min
1.25 +/-0.12
FT245RL
YYXX-A
1
14 15
28
FTDI
5.30 +/-0.30
7.80 +/-0.40
10.20 +/-0.30
1.02 Typ.
0.30 +/-0.012
0.65 +/-0.026
XXXXXXXXXXXX
Copyright © 2010 Future Technology Devices International Limited 31
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Clearance No.: FTDI# 39
9.2 QFN-32 Package Dimensions
Figure 9.2 QFN-32 Package Dimensions
The FT245RQ is supplied in a RoHS compliant leadless QFN-32 package. The package is lead ( Pb ) free,
and uses a ‘green’ compound. The package is fully compliant with European Union directive 2002/95/EC.
This package is nominally 5.00mm x 5.00mm. The solder pads are on a 0.50mm pitch. The above
mechanical drawing shows the QFN-32 package. All dimensions are in millimetres.
The centre pad on the base of the FT245RQ is not internally connected, and can be left unconnected, or
connected to ground (recommended).
The date code format is YYXX where XX = 2 digit week number, YY = 2 digit year number.
The code XXXXXXX is the manufacturing LOT code. This only applies to devices manufactured after April
2009.
Indicates Pin #1
(Laser Marked)
FT245RQ
32 25
24
17
169
8
1
YYXX-A
FTDI
5.000 +/-0.075
5. 000 +/-0.075
3.200 +/-0.100
3. 200 +/-0.100
0.500
0. 150 Max
Pin #1 ID
0. 900
+/-0.100
0. 200 0.050
2
1
3
4
5
6
7
8
23
24
22
21
20
19
18
17
2526272829303132
161514131211109
0. 200 Min
Note: The pin #1 ID is connected internally to the device’s central
heat sink area . It is recommended to ground the central heat sink
area of the device.
Dimensions in mm.
Central
Heat Sink
Area
0.500 +/-0.050
0.250 +/-0.050
XXXXXXX
Copyright © 2010 Future Technology Devices International Limited 32
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Clearance No.: FTDI# 39
9.3 QFN-32 Package Typical Pad Layout
Figure 9.3 Typical Pad Layout for QFN-32 Package
9.4 QFN-32 Package Typical Solder Paste Diagram
2.5 +/- 0.0375
2.5 +/- 0.0375
Figure 9.4 Typical Solder Paste Diagram for QFN-32 Package
1
17
25
0.500
0.30
0.200 Min
0.500
+/-0.050
0.150 Max
0.20
0.100
3.200 +/-0.100
3.200 +/-0.100
2.50
2.50
Optional GND
Connection
Optional GND
Connection
9
Copyright © 2010 Future Technology Devices International Limited 33
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9.5 Solder Reflow Profile
The FT245R is supplied in Pb free 28 LD SSOP and QFN-32 packages. The recommended solder reflow
profile for both package options is shown in 0.
Figure 9.5 FT245R Solder Reflow Profile
The recommended values for the solder reflow profile are detailed in Table 9.1. Values are shown for both
a completely Pb free solder process (i.e. the FT245R is used with Pb free solder), and for a non-Pb free
solder process (i.e. the FT245R is used with non-Pb free solder).
Profile Feature
Pb Free Solder Process
Non-Pb Free Solder Process
Average Ramp Up Rate (Ts to Tp)
3°C / second Max.
3°C / Second Max.
Preheat
- Temperature Min (Ts Min.)
- Temperature Max (Ts Max.)
- Time (ts Min to ts Max)
150°C
200°C
60 to 120 seconds
100°C
150°C
60 to 120 seconds
Time Maintained Above Critical
Temperature TL:
- Temperature (TL)
- Time (tL)
217°C
60 to 150 seconds
183°C
60 to 150 seconds
Peak Temperature (Tp)
260°C
240°C
Time within 5°C of actual Peak
Temperature (tp)
20 to 40 seconds
20 to 40 seconds
Ramp Down Rate
6°C / second Max.
6°C / second Max.
Time for T= 25°C to Peak Temperature,
Tp
8 minutes Max.
6 minutes Max.
Table 9.1 Reflow Profile Parameter Values
Critical Zone: when
T is in the range
T to T
Temperature, T (Degrees C)
Time, t (seconds)
25 P
T = 25º C to T
tp
Tp
TL
t
Preheat
S
tL
Ramp Up Lp
Ramp
Down
T Max
S
T Min
S
Copyright © 2010 Future Technology Devices International Limited 34
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FT245R USB FIFO IC Datasheet Version 2.13
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10 Alternative Parts
The following list of parts are not all direct drop in replacements but offer similar features as an
alternative to the FT245R. The FT-X series is the latest device family offering reduced power and pin
count with additional features such as battery charge detection, while the Hi-Speed solution offers faster
interfacing.
FT245R
FT240X
FT232H
Description
Single
channel USB
to
asynchronous
FIFO
Single channel
USB to
asynchronous
FIFO
Single channel
USB to
asynchronous
FIFO (Need MTP
to configure)
USB Speed
USB 2.0 full
speed
USB 2.0 full
speed
USB 2.0 hi-
speed
UART Data
Rates
1 Mbyte/s
1Mbyte/s
8 Mbyte/s
MTP for storing
descriptors
Internal
Internal
External
Package
options
32 pin QFN
28 pin SSOP
24 pin QFN
24 pin SSOP
48 pin QFN
48 pin LQFP
Datasheet
FT245R
FT234XD
FT232H
Table 10.1 FT245R alternative solutions
Copyright © 2010 Future Technology Devices International Limited 35
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FT245R USB FIFO IC Datasheet Version 2.13
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11 Contact Information
Head Office – Glasgow, UK
Future Technology Devices International Limited
Unit 1, 2 Seaward Place
Centurion Business Park
Glasgow, G41 1HH
United Kingdom
Tel: +44 (0) 141 429 2777
Fax: +44 (0) 141 429 2758
E-mail (Sales) sales1@ftdichip.com
E-mail (Support) support1@ftdichip.com
E-mail (General Enquiries) admin1@ftdichip.com
Web Site URL http://www.ftdichip.com
Web Shop URL http://www.ftdichip.com
Branch Office – Taipei, Taiwan
Future Technology Devices International Limited
(Taiwan)
2F, No 516, Sec. 1 NeiHu Road
Taipei 114
Taiwan, R.O.C.
Tel: +886 (0) 2 8791 3570
Fax: +886 (0) 2 8791 3576
E-mail (Sales) tw.sales1@ftdichip.com
E-mail (Support) tw.support1@ftdichip.com
E-mail (General Enquiries) tw.admin1@ftdichip.com
Web Site URL http://www.ftdichip.com
Branch Office – Tigard, Oregon, USA
Future Technology Devices International Limited (USA)
7130 SW Fir Loop
Tigard, OR 97223-8160
USA
Tel: +1 (503) 547 0988
Fax: +1 (503) 547 0987
E-Mail (Sales)
us.sales@ftdichip.com
E-Mail (Support)
us.support@ftdichip.com
E-Mail (General Enquiries)
us.admin@ftdichip.com
Branch Office – Shanghai, China
Future Technology Devices International Limited
(China)
Room 1103, No. 666 West Huaihai Road,
Shanghai, 200052
China
Tel: +86 21 62351596
Fax: +86 21 62351595
E-Mail (Sales): cn.sales@ftdichip.com
E-Mail (Support): cn.support@ftdichip.com
E-Mail (General Enquiries): cn.admin1@ftdichip.com
Web Site URL: http://www.ftdichip.com
Distributor and Sales Representatives
Please visit the Sales Network page of the FTDI Web site for the contact details of our distributor(s) and
sales representative(s) in your country.
System and equipment manufacturers and designers are responsible to ensure that their systems, and any Future Technology Devices
International Ltd (FTDI) devices incorporated in their systems, meet all applicable safety, regulatory and system-level performance
requirements. All application-related information in this document (including application descriptions, suggested FTDI devices and other
materials) is provided for reference only. While FTDI has taken care to assure it is accurate, this information is subject to customer
confirmation, and FTDI disclaims all liability for system designs and for any applications assistance provided by FTDI. Use of FTDI
devices in life support and/or safety applications is entirely at the user’s risk, and the user agrees to defend, indemnify and hold
harmless FTDI from any and all damages, claims, suits or expense resulting from such use. This document is subject to change without
notice. No freedom to use patents or other intellectual property rights is implied by the publication of this document. Neither the whole
nor any part of the information contained in, or the product described in this document, may be adapted or reproduced in any material
or electronic form without the prior written consent of the copyright holder. Future Technology Devices International Ltd, Unit 1, 2
Seaward Place, Centurion Business Park, Glasgow G41 1HH, United Kingdom. Scotland Registered Company Number: SC136640
.
Copyright © 2010 Future Technology Devices International Limited 36
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FT245R USB FIFO IC Datasheet Version 2.13
Clearance No.: FTDI# 39
Appendix A - References
Useful Application Notes
http://www.ftdichip.com/Documents/AppNotes/AN232R-01_FT232RBitBangModes.pdf
http://www.ftdichip.com/Documents/AppNotes/AN_107_AdvancedDriverOptions_AN_000073.pdf
http://www.ftdichip.com/Documents/AppNotes/AN232R-02_FT232RChipID.pdf
http://www.ftdichip.com/Documents/AppNotes/AN_121_FTDI_Device_EEPROM_User_Area_Usage.pdf
http://www.ftdichip.com/Documents/AppNotes/AN_120_Aliasing_VCP_Baud_Rates.pdf
http://www.ftdichip.com/Documents/AppNotes/AN_100_Using_The_FT232_245R_With_External_Osc(FT_
000067).pdf
http://www.ftdichip.com/Resources/Utilities/AN_126_User_Guide_For_FT232_Factory%20test%20utility.
pdf
http://www.ftdichip.com/Documents/AppNotes/AN232B-05_BaudRates.pdf
http://www.ftdichip.com/Documents/InstallGuides.htm
Copyright © 2010 Future Technology Devices International Limited 37
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Appendix B - List of Figures and Tables
List of Figures
Figure 2.1 FT245R Block Diagram ................................................................................................... 4
Figure 3.1 SSOP Package Pin Out and Schematic Symbol ................................................................... 7
Figure 3.2 QFN-32 Package Pin Out and schematic symbol .............................................................. 10
Figure 3.3 FIFO Read Cycle .......................................................................................................... 13
Figure 3.4 FIFO Write Cycle ......................................................................................................... 14
Figure 7.1 Bus Powered Configuration ........................................................................................... 23
Figure 7.2 Self Powered Configuration ........................................................................................... 24
Figure 7.3 Bus Powered with Power Switching Configuration ............................................................ 25
Figure 7.4 USB Bus Powered with +3.3V or +5V External Logic Power Supply .................................... 26
Figure 8.1 USB to MCU FIFO Interface ........................................................................................... 27
Figure 10.1 SSOP-28 Package Dimensions ..................................................................................... 30
Figure 10.2 QFN-32 Package Dimensions ....................................................................................... 31
Figure 10.3 Typical Pad Layout for QFN-32 Package ........................................................................ 32
Figure 10.4 Typical Solder Paste Diagram for QFN-32 Package ......................................................... 32
Figure 10.5 FT245R Solder Reflow Profile ....................................................................................... 33
List of Tables
Table 3.1 USB Interface Group ....................................................................................................... 7
Table 3.2 Power and Ground Group ................................................................................................. 8
Table 3.3 Miscellaneous Signal Group .............................................................................................. 8
Table 3.4 FIFO Interface Group (see note 3) .................................................................................... 9
Table 3.5 USB Interface Group ..................................................................................................... 10
Table 3.6 Power and Ground Group ............................................................................................... 11
Table 3.7 Miscellaneous Signal Group ............................................................................................ 11
Table 3.8 FIFO Interface Group (see note 3) .................................................................................. 12
Table 3.9 FIFO Read Cycle Timings ............................................................................................... 13
Table 3.10 FIFO Write Cycle ......................................................................................................... 14
Table 5.1 Absolute Maximum Ratings ............................................................................................ 17
Table 5.2 Operating Voltage and Current ....................................................................................... 18
Table 5.3 UART and CBUS I/O Pin Characteristics (VCCIO = +5.0V, Standard Drive Level) .................. 18
Table 5.4 UART and CBUS I/O Pin Characteristics (VCCIO = +3.3V, Standard Drive Level) .................. 18
Table 5.5 UART and CBUS I/O Pin Characteristics (VCCIO = +2.8V, Standard Drive Level) .................. 19
Table 5.6 UART and CBUS I/O Pin Characteristics (VCCIO = +1.8V, Standard Drive Level) .................. 19
Table 5.7 UART and CBUS I/O Pin Characteristics (VCCIO = +5.0V, High Drive Level) ......................... 19
Table 5.8 UART and CBUS I/O Pin Characteristics (VCCIO = +3.3V, High Drive Level) ......................... 19
Table 5.9 UART and CBUS I/O Pin Characteristics (VCCIO = +2.8V, High Drive Level) ......................... 20
Table 5.10 UART and CBUS I/O Pin Characteristics (VCCIO = +1.8V, High Drive Level) ....................... 20
Table 5.11 RESET# and TEST Pin Characteristics ............................................................................ 20
Table 5.12 USB I/O Pin (USBDP, USBDM) Characteristics ................................................................. 21
Table 5.13 EEPROM Characteristics ............................................................................................... 21
Copyright © 2010 Future Technology Devices International Limited 38
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FT245R USB FIFO IC Datasheet Version 2.13
Clearance No.: FTDI# 39
Table 5.14 Internal Clock Characteristics ....................................................................................... 21
Table 5.15 OSCI, OSCO Pin Characteristics – see Note 1 ................................................................. 22
Table 5.16 FT245RL Thermal Characteristics .................................................................................. 22
Table 5.17 FT245RQ Thermal Characteristics .................................................................................. 22
Table 8.1 Default Internal EEPROM Configuration ............................................................................ 29
Table 9.1 Reflow Profile Parameter Values ..................................................................................... 33
Table 10.1 FT245R alternative solutions ........................................................................................ 34
Copyright © 2010 Future Technology Devices International Limited 39
Document No.: FT_000052
FT245R USB FIFO IC Datasheet Version 2.13
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Appendix C - Revision History
Document Title: USB UART IC FT245R
Document Reference No.: FT_000052
Clearance No.: FTDI# 39
Product Page: http://www.ftdichip.com/FTProducts.htm
Document Feedback: Send Feedback
Version 0.90 Initial Datasheet Created August 2005
Version 0.94 Revised Pre-release datasheet October 2005
Version 1.00 Full datasheet released December 2005
Version 1.02 Minor revisions to datasheet released December 2005
Version 1.03 Manufacturer ID added to default EEPROM data January 2006
Version 1.04 Buffer sizes added January 2006
Version 1.05 QFN-32 Package pad layout and solder paste diagrams added January 2006
Version 2.00 Reformatted, added notes for 3.3V operation; June 2008
Part numbers, TID, corrected; QFN Package drawing corrected.
Added FIFO characteristics for +1.8V; Added MTTF data
Corrected the input switching threshold and input hysteresis figures for VCCIO=+5V
Version 2.01 Corrected the RX and TX Buffer data flow direction in the block
Diagram Figure 2.1 July 2008
Version 2.02 Removed repeated section of table 8.1
Improved graphics on Figures 6.2, 6.3, 6.4 and 7.1
Add Packing details
Changed USB suspend current spec from 500uA to 2.5m
Corrected Figure 9.2 QFN dimensions. August 2008
Version 2.03 Amended definition of FIFO TX and RX buffers to be consistent
Updated company contact information. February 2009
Version 2.04 Corrected Tape and Reel quantities
Added LOT numbers to the device markings.
Clarified VCC operation and added section headed “Using an external Oscillator”
Added 3V3 regulator output tolerance April 2009
Version 2.05 Corrected Tx and RX buffer sizes on front page June 2009
Version 2.06 Additional dimensions added to QFN solder profile June 2009
Version 2.07 Changed label ‘D6’ to 'D7' (pin 3) on FT245RQ schematic symbol
Updated to latest TID number
Added Window 7 support October 2009
Version 2.08 Modified package dimensions to 5.0 x 5.0 +/-0.075mm. December 2009
and Solder paste diagram to 2.50 x 2.50 +/-0.0375mm
Added FT_PROG utility references
Added Appendix A-references
Corrected USB-IF TID
Version 2.09 Updated section 6.2, Figure 6.2 and the note, May 2010
Updated section 5.3, Table 5.13, EEPROM data retention time
Version 2.10 Removed RD# and WR# references on BitBang modes July 2010
Corrected US Support email address. Added USB Compliance logo
Copyright © 2010 Future Technology Devices International Limited 40
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Clearance No.: FTDI# 39
Version 2.11 Updated USB-IF TID for Rev C April 2011
Version 2.12 Corrected TID for Rev C April 2011
Version 2.13 Added Thermal Characteristics (Section 5.5) February 2015
Added document information and feedback to revision history
Added section 10 on alternative parts
Mouser Electronics
Authorized Distributor
Click to View Pricing, Inventory, Delivery & Lifecycle Information:
FTDI:
FT245RL-REEL FT245RQ-REEL FT245RL-TUBE FT245RQ-TRAY