ETC FT245BQ

FT245BQ USB FIFO ( USB - Parallel ) I.C.
The FT245BQ is the lead free version of the 2nd generation of FTDI’s popular USB FIFO I.C. This device not only
adds extra functionality to its FT8U245AM predecessor and reduces external component count, but also maintains a
high degree of pin compatibility with the original, making it easy to upgrade or cost reduce existing designs as well as
increasing the potential for using the device in new application areas.
1.0
Features
HARDWARE FEATURES
•
•
UHCI / OHCI / EHCI host controller compatible
Single Chip USB  Parallel FIFO bi-directional
•
USB 1.1 and USB 2.0 compatible
Data Transfer
•
USB VID, PID , Serial Number and Product
•
Transfer Data rate to 1M Byte / Sec - D2XX Drivers
•
Transfer Data rate to 300 Kilobyte / Sec - VCP
•
EEPROM programmable on-board via USB
Drivers
•
Compact 5 x 5 mm Lead free RoHS compliant
•
Description strings in external EEPROM
Simple to interface to MCU / PLD/ FPGA logic with
QFN32 package
a 4 wire handshake interface
VIRTUAL COM PORT (VCP) DRIVERS for
Entire USB protocol handled on-chip… no USB-
-
Windows 98 and Windows 98 SE
specific firmware programming required
-
Windows 2000 / ME / XP
FTDI’s royalty-free VCP and D2XX drivers
-
Windows CE 4.2
eliminate the requirement for USB driver
-
MAC OS-8 and OS-9
development in most cases.
-
MAC OS-X
384 Byte FIFO Tx buffer / 128 Byte FIFO Rx Buffer
-
Linux 2.40 and greater
for high data throughput.
D2XX (USB Direct Drivers + DLL S/W Interface)
New Send Immediate support via SI Pin for
-
Windows 98 and Windows 98 SE
optimised data throughput.
-
Windows 2000 / ME / XP
Support for USB Suspend / Resume through
-
Windows CE 4.2
PWREN# and WAKEUP pins.
-
Linux 2.4 and Greater
Support for high power USB Bus powered devices
APPLICATION AREAS
through PWREN# pin
-
Easy MCU / PLD / FPGA interface to USB
•
Adjustable RX buffer timeout
-
Upgrading Legacy Peripheral Designs to USB
•
In-built support for event characters
-
USB Instrumentation
•
Integrated level converter on FIFO and control
-
USB Industrial Control
signals for interfacing to 5V and 3.3V logic
-
USB Audio and Low Bandwidth Video data transfer
•
Integrated 3.3V regulator for USB IO
-
PDA  USB data transfer
•
Integrated Power-On-Reset circuit
-
USB MP3 Player Interface
•
Integrated 6MHz – 48Mhz clock multiplier PLL
-
USB FLASH Card Reader / Writers
•
USB Bulk or Isochronous data transfer modes
-
Set Top Box (S.T.B.) PC - USB interface
•
New Bit-Bang Mode allows the data bus to be used
-
USB Digital Camera Interface
as an 8 bit general purpose IO Port without the
-
USB Hardware Modems
need for MCU or other support logic.
-
USB Wireless Modems
•
•
•
•
•
•
•
4.35V to 5.25V single supply operation
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 1 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
1.1 General Description
The FT245BQ provides an easy cost-effective method of transferring data to / from a peripheral and a host P.C. at up
to 8 Million bits (1 Megabyte) per second. Its simple, FIFO-like design makes it easy to interface to any microcontroller
or microprocessor via IO ports.
To send data from the peripheral to the host computer, simply write the byte-wide data into the module when TXE# is
low. If the (384-byte) transmit buffer fills up or is busy storing the previously written byte, the device keeps TXE# high
in order to stop further data from being written until some of the FIFO data has been transferred over USB to the host.
TXE# goes high after every byte written.
When the host sends data to the peripheral over USB, the device will take RXF# low to let the peripheral know that at
least one byte of data is available. The peripheral can read a data byte every time RXF# goes low. RXF# goes high
after every byte read.
By using FTDI’s virtual COM port drivers, the peripheral looks like a standard COM port to the application software.
Commands to set the baud rate are ignored - the device always transfers data at its fastest rate regardless of the
application’s baud-rate setting. Alternatively, FTDI’s D2XX drivers allow application software to access the device
“directly” through a published DLL based API. Details of the current VCP and D2XX driver can be found on FTDI’s web
site ( http://www.ftdichip.com )
2.0
Enhancements
This section summarises the enhancements of the 2nd generation device compared to its FT8U245AM predecessor.
For further details, consult the device pin-out description and functional descriptions.
•
Integrated Power-On-Reset (POR) Circuit
The device now incorporates an internal POR
function. The existing RESET# pin is maintained
•
Integrated Level Converter on FIFO interface
in order to allow external logic to reset the device
and control signals
where required, however for many applications
The previous devices would drive the FIFO and
this pin can now be either left N/C or hard wired
control signals at 5V CMOS logic levels. The
to VCC. In addition, a new reset output pin
new device has a separate VCCIO pin allowing
(RSTOUT#) is provided in order to allow the new
the device to directly interface to 3.3V and other
POR circuit to provide a stable reset to external
logic families without the need for external level
MCU and other devices. RSTOUT# was the TEST
converter I.C.’s
pin on the previous generation of devices.
•
•
Power Management control for USB Bus
Integrated RCCLK Circuit
Powered, high current devices
In the previous devices, an external RC circuit
A new PWREN# signal is provided which can be
was required to ensure that the oscillator and
used to directly drive a transistor or P-Channel
clock multiplier PLL frequency was stable prior
MOSFET in applications where power switching
to enabling the clock internal to the device. This
of external circuitry is required. A new EEPROM
circuit is now embedded on-chip – the pin assigned
based option makes the device pull gently down
to this function is now designated as the TEST pin
its FIFO interface lines when the power is shut
and should be tied to GND for normal operation.
off (PWREN# is High). In this mode, any residual
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 2 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
voltage on external circuitry is bled to GND when
was fixed at 16ms timeout. This timeout is now
power is removed thus ensuring that external
programmable over USB in 1ms increments
circuitry controlled by PWREN# resets reliably
from 1ms to 255ms, thus allowing the device to
when power is restored. PWREN# can also be
be better optimised for protocols requiring faster
used by external circuitry to determine when USB
response times from short data packets.
is in suspend mode (PWREN# goes high).
•
•
Relaxed VCC Decoupling
Send Immediate / WakeUp (SI / WU) signal
The 2nd generation devices now incorporate a level
The new Send Immediate / WakeUp signal
of on-chip VCC decoupling. Though this does
combines two functions on a single pin. If USB is
not eliminate the need for external decoupling
in suspend mode (and remote wakeup is enabled
capacitors, it significantly improves the ease of
in the EEPROM), strobing this pin low will cause
PCB design requirements to meet FCC, CE and
the device to request a resume from suspend
other EMI related specifications.
(WakeUp) on the USB Bus. Normally, this can
be used to wake up the Host PC. During normal
•
Bit Bang Mode
operation, if this pin is strobed low any data in the
The 2nd generation device has a new option
device RX buffer will be sent out over USB on the
referred to as “Bit Bang” mode. In Bit Bang mode,
next Bulk-IN request from the drivers regardless of
the eight FIFO data lines can be switched between
the packet size. This can be used to optimise USB
FIFO interface mode and an 8-bit Parallel IO
transfer speed for some applications.
port. Data packets can be sent to the device and
they will be sequentially sent to the interface at
•
Lower Suspend Current
a rate controlled by an internal timer (equivalent
Integration of RCCLK within the device and internal
to the prescaler of the FT232BQ device). As well
design improvements reduce the suspend current
as allowing the device to be used stand-alone
of the FT245BQ to under 100uA typical (excluding
as a general purpose IO controller for example
the 1.5K pull-up on USBDP) in USB suspend
controlling lights, relays and switches, some other
mode. This allows greater margin for peripherals to
interesting possibilities exist. For instance, it may
meet the USB Suspend current limit of 500uA.
be possible to connect the device to an SRAM
configurable FPGA as supplied by vendors such as
•
•
Support for USB Isochronous Transfers
Altera and Xilinx. The FPGA device would normally
Whilst USB Bulk transfer is usually the best
be un-configured (i.e. have no defined function) at
choice for data transfer, the scheduling time of the
power-up. Application software on the PC could
data is not guaranteed. For applications where
use Bit Bang Mode to download configuration
scheduling latency takes priority over data integrity
data to the FPGA which would define its hardware
such as transferring audio and low bandwidth
function, then after the FPGA device is configured
video data, the new device now offers an option of
the FT245BQ can switch back into FIFO interface
USB Isochronous transfer via an option bit in the
mode to allow the programmed FPGA device
EEPROM.
to communicate with the PC over USB. This
Programmable FIFO TX Buffer Timeout
approach allows a customer to create a “generic”
In the previous device, the TX buffer timeout
USB peripheral who’s hardware function can be
used to flush remaining data from the TX buffer
defined under control of the application software.
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 3 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
The FPGA based hardware can be easily upgraded
•
Multiple Device Support without EEPROM
or totally changed simply by changing the FPGA
When no EEPROM (or a blank or invalid
configuration data file. Application notes, software
EEPROM) is attached to the device, the FT245BQ
and development modules for this application area
no longer gives a serial number as part of its
will be available from FTDI and other 3 party
USB descriptor. This allows multiple devices to
developers.
be simultaneously connected to the same PC.
rd
However, we still highly recommend that EEPROM
•
is used, as without serial numbers a device can
Less External Support Components
As well as eliminating the RCCLK RC network, and
only be identified by which hub port in the USB tree
for most applications the need for an external reset
it is connected to which can change if the end user
circuit, we have also eliminated the requirement
re-plugs the device into a different USB port.
for a 100K pull-up on EECS to select 6MHz
operation. When the FT245BQ is being used
•
EEREQ# / EEGNT#
without the configuration EEPROM, EECS, EESK
These (FT8U245AM) pins are no longer supported
and EEDATA can now be left n/c. For circuits
on the FT245BQ device. They have been replaced
requiring a long reset time (where the device is
with the new SI / WU and PWREN# signals
reset externally using a reset generator I.C., or
respectively.
reset is controlled by the IO port of a MCU, FPGA
or ASIC device) an external transistor circuit is
no longer required as the 1.5K pull-up resistor on
USBDP can be wired to the RSTOUT# pin instead
of to 3.3V. Note : RSTOUT# drives out at 3.3V
level, not at 5V VCC level. This is the preferred
configuration for new designs.
•
Extended EEPROM Support
The previous generation of devices only supported
EEPROM of type 93C46 (64 x 16 bit). The new
devices will also work with EEPROM type 93C56
(128 x 16 bit) and 93C66 (256 x 16 bit). The extra
space is not used by the device, however it is
available for use by other external MCU / logic
whilst the FT245BQ is being held in reset.
•
USB 2.0 ( full speed option )
A new EEPROM based option allows the FT245BQ
to return a USB 2.0 device descriptor as opposed
to USB 1.1. Note : The device would be a USB 2.0
Full Speed device (12Mb/s) as opposed to a USB
2.0 High Speed device (480Mb/s).
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 4 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
3.0
Block Diagram ( simplified )
VCC
3V3OUT
Send Immediate / WakeUP
PWREN#
3.3 Volt
LDO
Regulator
USBDP
USBDM
USB
Transceiver
FIFO Receive
Buffer
128 Bytes
Serial Interface
Engine
( SIE )
FIFO
Controller
USB
Protocol Engine
D0
D1
D2
D3
D4
D5
D6
D7
RD#
WR
RXF#
TXE#
FIFO Transmit
Buffer
384 Bytes
USB DPLL
3V3OUT
XTOUT
XTIN
48MHz
6MHZ
Oscillator
•
•
EECS
EESK
EEDATA
12MHz
GND
TEST
3.1
EEPROM
Interface
x8 Clock
Multiplier
RESET
GENERATOR
RESET#
Functional Block Descriptions
3.3V LDO Regulator
The 3.3V LDO Regulator generates the 3.3 volt
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 RSTOUT# pin. The main function of this block
is to power the USB Transceiver and the Reset
Generator Cells rather than to power external logic.
However, external circuitry requiring 3.3V nominal
at a current of not greater than 5mA could also
draw its power from the 3V3OUT pin if required.
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 3.3 volt level slew
RSTOUT#
•
USB DPLL
The USB DPLL cell locks on to the incoming NRZI
USB data and provides separate recovered clock
and data signals to the SIE block.
•
6MHz Oscillator
The 6MHz Oscillator cell generates a 6MHz
reference clock input to the x8 Clock multiplier from
an external 6MHz crystal or ceramic resonator.
•
x8 Clock Multiplier
The x8 Clock Multiplier takes the 6MHz input
from the Oscillator cell and generates a 12MHz
reference clock for the SIE, USB Protocol Engine
and FIFO controller blocks. It also generates a
48MHz reference clock for the USB DPLL.
rate control signalling, whilst a differential receiver
and two single ended receivers provide USB data
in, SEO and USB Reset condition detection.
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 5 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
•
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 to the
USB 2.0 specification, it performs bit stuffing / unstuffing and CRC5 / CRC16 generation / checking
on the USB data stream.
enumeration is required. RSTOUT# will be low for
approximately 5ms after VCC has risen above 3.5V
AND the device oscillator is running AND RESET#
is high. RESET# should be tied to VCC unless it
is a requirement to reset the device from external
logic or an external reset generator I.C.
•
•
USB Protocol Engine
The USB Protocol Engine manages the data
stream from the device USB control endpoint. It
handles the low level USB protocol (Chapter 9)
requests generated by the USB host controller
and the commands for controlling the functional
parameters of the FIFO.
•
FIFO Receive Buffer (128 bytes)
Data sent from the USB Host to the FIFO via
the USB data out endpoint is stored in the FIFO
Receive Buffer and is removed from the buffer by
reading the FIFO contents using RD#.
•
FIFO Transmit Buffer (384 bytes)
Data written into the FIFO using WR# is stored in
the FIFO Transmit Buffer. The Host removes Data
from the FIFO Transmit Data by sending a USB
request for data from the device data in endpoint.
•
FIFO Controller
The FIFO Controller handles the transfer of data
between the external FIFO interface pins and the
FIFO Transmit and Receive buffers.
•
RESET Generator
The Reset Generator Cell provides a reliable
power-on reset to the device internal circuitry
on power up. An additional RESET# input and
RSTOUT# output are provided to allow other
devices to reset the FT245BQ, or the FT245BQ
to reset other devices respectively. During reset,
RSTOUT# is driven low, otherwise it drives out
at the 3.3V provided by the onboard regulator.
RSTOUT# can be used to control the 1.5K
pull-up on USBDP directly where delayed USB
DS245BQ Version 1.6
EEPROM Interface
Though the FT245BQ will work without the optional
EEPROM, an external 93C46 (93C56 or 93C66)
EEPROM can be used to customise the USB VID,
PID, Serial Number, Product Description Strings
and Power Descriptor value of the FT245BQ for
OEM applications. Other parameters controlled
by the EEPROM include Remote Wake Up,
Isochronous Transfer Mode, Soft Pull Down on
Power-Off and USB 2.0 descriptor modes.
The EEPROM should be a 16 bit wide
configuration such as a MicroChip 93LC46B or
equivalent capable of a 1Mb/s clock rate at VCC =
4.35V to 5.25V. The EEPROM is programmableon board over USB using a utility available from
FTDI’s web site ( http://www.ftdichip.com ). This
allows a blank part to be soldered onto the PCB
and programmed as part of the manufacturing and
test process.
If no EEPROM is connected (or the EEPROM
is blank), the FT245BQ will use its built-in
default VID, PID Product Description and Power
Descriptor Value. In this case, the device will not
have a serial number as part of the USB descriptor.
© Future Technology Devices Intl. Ltd. 2005
Page 6 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
4.0
Device Pin-Out
Figure 1
Pin-Out
(QFN32 Package )
32
Figure 2
Pin-Out
(Schematic Symbol )
25
8
FT245BQ
FT232BQ
XXYY
7
V
C
C
13
6
V
C
C
26
FTDI
A
V
V
3V3OUT C
3
30
24
1
V
C
C
I
O
USBDM
5
4
16
9
27
25
26
27
28
29
30
31
28
32
32
24
1
D3
USBDP
D4
3
21
4
20
5
19
6
18
7
17
8
16
15
14
DS245BQ Version 1.6
13
12
11
10
31
D6
RESET#
D7
XTIN
RD#
WR
XTOUT
TXE#
EECS
RXF#
EESK
SI / WU
EEDATA
TEST
A
G
N
D
PWREN#
G
N
D
25
24
23
22
21
20
19
18
16
15
14
12
11
10
G
N
D
17
22
RSTOUT#
9
2
2
D5
29
23
1
D1
D2
17
8
D0
9
© Future Technology Devices Intl. Ltd. 2005
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FT245BQ USB FIFO ( USB - Parallel ) I.C.
4.1
Signal Descriptions
Table 1 - FT245BQ - PINOUT DESCRIPTION
FIFO DATA BUS GROUP (*** Note 1)
Pin#
Signal
Type
Description
25
DO
I/O
FIFO Data Bus Bit 0
24
D1
I/O
FIFO Data Bus Bit 1
23
D2
I/O
FIFO Data Bus Bit 2
22
D3
I/O
FIFO Data Bus Bit 3
21
D4
I/O
FIFO Data Bus Bit 4
20
D5
I/O
FIFO Data Bus Bit 5
19
D6
I/O
FIFO Data Bus Bit 6
18
D7
I/O
FIFO Data Bus Bit 7
FIFO CONTROL INTERFACE GROUP
Pin#
Signal
Type
Description
16
RD#
IN
Enables Current FIFO Data Byte on D0..D7 when low. Fetches the next FIFO
Data Byte (if available) from the Receive FIFO Buffer when RD# goes from low
to high. *** Note 1
15
WR
IN
Writes the Data Byte on the D0..D7 into the Transmit FIFO Buffer when WR goes
from high to low. *** Note 1
14
TXE#
OUT
When high, do not write data into the FIFO. When low, data can be written into
the FIFO by strobing WR high then low. *** Note 2
12
RXF#
OUT
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 *** Note 2
USB INTERFACE GROUP
Pin#
Signal
Type
Description
7
USBDP
I/O
USB Data Signal Plus (Requires 1.5K pull-up to 3V3OUT or RSTOUT#)
8
USBDM
I/O
USB Data Signal Minus
EEPROM INTERFACE GROUP
Pin#
Signal
Type
Description
32
EECS
I/O
EEPROM – Chip Select. For 48MHz operation pull EECS to GND using a 10K
resistor. For 6MHz operation no resistor is required. *** Note 3
1
EESK
OUT
Clock signal to EEPROM. Adding a 10K pull down resistor onto EESK will cause
the FT245BQ to use USB Product ID 6005 (hex) instead of 6001 (hex). All of the
other USB device descriptors are unchanged. *** Note 3
2
EEDATA
I/O
EEPROM – Data I/O Connect directly to Data-In of the EEPROM and to DataOut of the EEPROM via a 2.2K resistor. Also pull Data-Out of the EEPROM to
VCC via a 10K resistor for correct operation. *** Note 3
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 8 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
POWER CONTROL GROUP
Pin#
Signal
Type
Description
10
PWREN#
OUT
Goes Low after the device is configured via USB, then high during USB suspend.
Can be used to control power to external logic using a P-Channel Logic Level
MOSFET switch. Enable the Interface Pull-Down Option in EEPROM when using
the PWREN# pin in this way.
11
SI / WU
IN
The Send Immediate / WakeUp signal combines two functions on a single pin. If
USB is in suspend mode (PWREN# = 1) and remote wakeup is enabled in the
EEPROM , strobing this pin low will cause the device to request a resume on the
USB Bus. Normally, this can be used to wake up the Host PC.
During normal operation (PWREN# = 0), if this pin is strobed low any data in the
device TX buffer will be sent out over USB on the next Bulk-IN request from the
drivers regardless of the pending packet size. This can be used to optimise USB
transfer speed for some applications. Tie this pin to VCCIO if not used.
MISCELLANEOUS SIGNAL GROUP
Pin#
Signal
Type
Description
4
RESET#
IN
Can be used by an external device to reset the FT245BQ. If not required, tie to
VCC.
5
RSTOUT#
OUT
Output of the internal Reset Generator. Stays high impedance for ~ 5ms after
VCC > 3.5V and the internal clock starts up, then clamps its output to the 3.3V
output of the internal regulator. Taking RESET# low will also force RSTOUT# to
drive low. RSTOUT# is NOT affected by a USB Bus Reset.
27
XTIN
IN
Input to 6MHz Crystal Oscillator Cell. This pin can also be driven by an external
6MHz clock if required. Note : Switching threshold of this pin is VCC/2, so if
driving from an external source, the source must be driving at 5V CMOS level or
a.c. coupled to centre around VCC/2.
28
XTOUT
OUT
Output from 6MHz Crystal Oscillator Cell. XTOUT stops oscillating during USB
suspend, so take care if using this signal to clock external logic.
31
TEST
IN
Puts device in I.C. test mode – must be tied to GND for normal operation.
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 9 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
POWER AND GND GROUP
Pin#
Signal
Type
Description
6
3V3OUT
OUT
3.3 volt Output from the integrated L.D.O. regulator This pin should be decoupled
to GND using a 33nF ceramic capacitor in close proximity to the device pin. Its
prime purpose is to provide the internal 3.3V supply to the USB transceiver cell
and the RSTOUT# pin. A small amount of current (<= 5mA) can be drawn from
this pin to power external 3.3V logic if required.
3,26
VCC
PWR
+4.35 volt to +5.25 volt VCC to the device core, LDO and none-FIFO interface
pins.
13
VCCIO
PWR
+3.0 volt to +5.25 volt VCC to the FIFO interface pins 10..12, 14..16 and 18..25.
When interfacing with 3.3V external logic in a bus powered design connect
VCCIO to a 3.3V supply generated from the USB bus. When interfacing with
3.3V external logic in a self powered design connect VCCIO to the 3.3V supply
of the external logic. Otherwise connect to VCC to drive out at 5V CMOS level.
9,17
GND
PWR
Device - Ground Supply Pins
30
AVCC
PWR
Device - Analog Power Supply for the internal x8 clock multiplier
29
AGND
PWR
Device - Analog Ground Supply for the internal x8 clock multiplier
Note 1 : In Input Mode, these pins are pulled to VCCIO via internal 200K resistors. These can be programmed to
gently pull low during USB suspend ( PWREN# = “1” ) by setting this option in the EEPROM.
Note 2: During device reset, these pins are tri-state but pulled up to VCCIO via internal 200K resistors.
Note 3: During device reset, these pins are tri-state but pulled up to VCC via internal 200K resistors.
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 10 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
FT245BQ TIMING DIAGRAM – FIFO READ CYCLE
T6
T5
RXF#
T1
RD#
T2
T3
D0..D7
T4
valid data
Time
Description
Min
Max
T1
RD Active Pulse Width
50
ns
T2
RD to RD Pre-Charge Time
50 + T6
ns
T3
RD Active to Valid Data *** Note 4
20
T4
Valid Data Hold Time from RD Inactive *** Note 4
0
T5
RD Inactive to RXF#
0
T6
RXF inactive after RD cycle
80
50
Unit
ns
ns
25
ns
ns
*** Note 4 - Load 30 pF
FT245BQ TIMING DIAGRAM – FIFO WRITE CYCLE
T12
T11
TXE#
T7
T8
WR
T10
T9
D0..D7
valid data
Time
Description
Min
T7
WR Active Pulse Width
50
ns
T8
WR to WR Pre-Charge Time
50
ns
T9
Data Setup Time before WR inactive
20
ns
T10
Data Hold Time from WR inactive
0
ns
T11
WR Inactive to TXE#
5
T12
TXE inactive after WR cycle
80
DS245BQ Version 1.6
Max
25
Unit
ns
ns
© Future Technology Devices Intl. Ltd. 2005
Page 11 of 24
5.0
FT245BQ USB FIFO ( USB - Parallel ) I.C.
Package Outline
Figure 3 – 32 LD LQFP Package Dimensions
5mm
FTDI
5mm
FT245BQ
FT232BQ
XXYY
2.7mm
0.5mm
2.7mm
0.4mm
0.5mm
0.25mm
0.75mm
0.2mm
0.02mm
The FT245BQ is supplied in a lead (Pb) free, leadless QFN package. This package has a 5 mm x 5 mm body with
no protruding pins, and is ideal for projects where package area is critical. In the above drawing all dimensions are in
millimetres. Note that there are two date code formats used - XXYY = Date Code where XX = 1 or 2 digit year number,
YY = 2 digit week number); or XYY-1 where X = 1 digit year number, YY = 2 digit week number. The FT245BQ is fully
compliant with the European Union RoHS directive.
A lead (Pb) free LQFP package version of the device is also available, part number FT245BL.
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 12 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
6.0
Absolute Maximum Ratings
These are the absolute maximum ratings for the FT245BQ device in accordance with the Absolute Maximum Rating System
(IEC 60134). Exceeding these may cause permanent damage to the device.
Parameter
Value
Storage Temperature
Units
–65 C to + 150 C
o
Floor Life (Out of Bag) at Factory Ambient
(30oC/60% Relative Humidity)
Degrees C
o
192 Hours (Level 3 Compliant)
**Note 5
Ambient Temperature (Power Applied)
0oC to + 70oC
M.T.B.F. (at 35 C)
Degrees C
247484 Hours ≈ 28 Years
o
VCC Supply Voltage
-0.5 to +6.00
V
DC Input Voltage - Inputs
-0.5 to +(VCC + 0.5)
V
DC Input Voltage - High Impedance Bidirectionals
-0.5 to +(VCC + 0.5)
V
DC Output Current – Outputs
24
mA
DC Output Current – Low Impedance Bidirectionals
24
mA
Power Dissipation (VCC = 5.25V)
500
mW
+/- 3000
V
+/-200
mA
Electrostatic Discharge Voltage (Human Body Model) (I < 1uA)
Latch Up Current (Vi = +/- 10V maximum, for 10 ms)
*** Note 5 - 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 110oC and baked for 8 to 10 hours.
6.1
D.C. Characteristics
DC Characteristics ( Ambient Temperature = 0 to 70oC )
Operating Voltage and Current
Parameter
Description
Min
Typ
Max
Units
Conditions
Vcc1
VCC Operating Supply Voltage
4.35
5.0
5.25
V
Vcc2
VCCIO Operating Supply Voltage
3.0
-
5.25
V
Icc1
Operating Supply Current
-
25
-
mA
Normal Operation
Icc2
Operating Supply Current
-
100
200
uA
USB Suspend *** Note 6
***Note 6 – Supply current excludes the 200uA nominal drawn by the external pull-up resistor on USBDP.
FIFO Data / Control Bus IO Pin Characteristics ( VCCIO = 5.0V )
Parameter
Description
Min
Typ
Max
Units
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 = 2 mA
Vin
Input Switching Threshold
1.3
1.6
1.9
V
*** Note 7
VHys
Input Switching Hysteresis
50
55
60
mV
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Conditions
Page 13 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
FIFO Data / Control Bus IO Pin Characteristics ( VCCIO = 3V to 3.6V )
Parameter
Description
Min
Typ
Max
Units
Conditions
Voh
Output Voltage High
2.2
2.7
3.2
V
I source = 2mA
Vol
Output Voltage Low
0.3
0.4
0.5
V
I sink = 4 mA
Vin
Input Switching Threshold
1.0
1.2
1.5
V
*** Note 7
VHys
Input Switching Hysteresis
20
25
30
mV
***Note 7 – Inputs or IO Pins in Input Mode have an internal 200K pull-up resistor to VCCIO.
XTIN / XTOUT Pin Characteristics
Parameter
Description
Min
Typ
Max
Units
Conditions
Voh
Output Voltage High
4.0
-
5.0
V
Fosc = 6MHz
Vol
Output Voltage Low
0.1
-
1.0
V
Fosc = 6MHz
Vin
Input Switching Threshold
1.8
2.5
3.2
V
RESET#, TEST, EECS, EESK, EEDATA, IO Pin Characteristics
Parameter
Description
Min
Typ
Max
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 = 2 mA
Vin
Input Switching Threshold
1.3
1.6
1.9
V
*** Note 8
VHys
Input Switching Hysteresis
50
55
60
mV
***Note 8 – EECS, EESK and EEDATA pins have an internal 200K pull-up resistor to VCC
RSTOUT Pin Characteristics
Parameter
Description
Min
Typ
Max
Units
Conditions
Voh
Output Voltage High
3.0
-
3.6
V
I source = 2mA
Vol
Output Voltage Low
0.3
-
0.6
V
I sink = 2 mA
Typ
Max
Units
USB IO Pin Characteristics
Parameter
Description
Min
UVoh
IO Pins Static Output ( High)
2.8
3.6
V
RI = 1.5K to 3V3Out ( D+ )
RI = 15K to GND ( D- )
UVol
IO Pins Static Output ( Low )
0
0.3
V
RI = 1.5K to 3V3Out ( D+ )
RI = 15K 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
UDrvZ
Driver Output Impedance
29
DS245BQ Version 1.6
Conditions
V
44
Ohm
© Future Technology Devices Intl. Ltd. 2005
*** Note 9
Page 14 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
7.0
Device Configuration Examples
7.1
Oscillator Configurations
Figure 4
3 Pin Ceramic Resonator Configuration
Figure 5
Crystal or 2-Pin Ceramic Resonator
FT245BM
FT245BM
27pF
27
3-Pin Resonator
6MHz
XTIN
27
XTIN
28
XTOUT
2 - Pin Resonator
or Crystal
6MHz
1M
27pF
28
XTOUT
Configuration
Figure 4 illustrates how to use the FT245BQ with a 3-Pin Ceramic Resonator. A suitable part would be a ceramic
resonator from Murata’s CERALOCK range. (Murata Part Number CSTCR6M00G15), or equivalent. 3-Pin ceramic
resonators have the load capacitors built into the resonator so no external loading capacitors are required. This
makes for an economical configuration. The accuracy of this Murata ceramic resonator is +/- 0.1% and it is specifically
designed for USB full speed applications. A 1 MOhm loading resistor across XTIN and XTOUT is recommended in
order to guarantee this level of accuracy.
Other ceramic resonators with a lesser degree of accuracy ( typically +/- 0.5% ) are technically outwith the USB
specification, but it has been calculated that using such a device will work satisfactorily in practice with a FT245BQ
design.
Figure 5 illustrates how to use the FT245BQ with a 6MHz Crystal or 2-Pin Ceramic Resonator. In this case, these
devices do not have in-built loading capacitors so these have to be added between XTIN, XTOUT and GND as
shown. A value of 27pF is shown as the capacitor in the example – this will be good for many crystals and some
resonators but do select the value based on the manufacturers recommendations wherever possible. If using a crystal,
use a parallel cut type. If using a resonator, see the previous note on frequency accuracy.
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 15 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
7.2
EEPROM Configuration
Figure 6
EEPROM Configuration
FT245BM
32
EECS
1
EESK
2
EEDATA
VCC
EEPROM - 93C46 / 56 / 66
Figure 6 illustrates how to connect the FT245BQ to the
93C46 (93C56 or 93C66) EEPROM. EECS (pin 32) is directly
connected to the chip select (CS) pin of the EEPROM. EESK
(pin 1) is directly connected to the clock (SK) pin of the
EEPROM. EEDATA (pin 2) is directly connected to the Data
In (Din) pin of the EEPROM. There is a potential condition
whereby both the Data Output (Dout) of the EEPROM
can drive out at the same time as the EEDATA pin of the
FT245BQ. To prevent potential data clash in this situation,
the Dout of the EEPROM is connected to EEDATA of the
FT245BQ via a 2.2 K resistor.
CS
VCC
Following a power-on reset or a USB reset, the FT245BQ will
7
2
SK
NC
scan the EEPROM to find out a) if an EEPROM is attached
2k2
3
6
DIN
NC
to the Device and b) if the data in the device is valid. If both
4
5
of these are the case, then the FT245BQ will use the data in
DOUT
GND
the EEPROM, otherwise it will use its built-in default values.
When a valid command is issued to the EEPROM from the
VCC
10k
FT245BQ, the EEPROM will acknowledge the command by
pulling its Dout pin low. In order to check for this condition, it
is necessary to pull Dout high using a 10K resistor. If the command acknowledge doesn’t happen then EEDATA will
be pulled high by the 10K resistor during this part of the cycle and the device will detect an invalid command or no
EEPROM present.
There are two varieties of these EEPROM’s on the market – one is configured as being 16 bits wide, the other is
configured as being 8 bits wide. These are available from many sources such as Microchip, ST Micro, ISSI etc. The
FT245BQ requires EEPROM’s with a 16-bit wide configuration such as the Microchip 93LC46B device. The EEPROM
must be capable of reading data at a 1Mb clock rate at a supply voltage of 4.35V to 5.25V. Most available parts are
1
8
capable of this.
Check the manufacturers data sheet to find out how to connect pins 6 and 7 of the EEPROM. Some devices specify
these as no-connect, others use them for selecting 8 / 16 bit mode or for test functions. Some other parts have their
pinout rotated by 90o so please select the required part and its options carefully.
It is possible to “share” the EEPROM between the FT245BQ and another external device such as an MCU. However,
this can only be done when the FT245BQ is in its reset condition as it tri-states its EEPROM interface at that time. A
typical configuration would use four bits of an MCU IO Port. One bit would be used to hold the FT245BQ reset (using
RESET#) on power-up, the other three would connect to the EECS, EESK and EEDATA pins of the FT245BQ in
order to read / write data to the EEPROM at this time. Once the MCU has read / written the EEPROM, it would take
RESET# high to allow the FT245BQ to configure itself and enumerate over USB.
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 16 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
7.3
USB Bus Powered and Self Powered Configuration
Figure 7
USB Bus Powered Configuration
USB "B"
Connector
Ferrite Bead
470R
VCC
1
2
27R
3
4
3
FT245BM
27R
6
10nF
33nF
8
7
26
V
C
C
V
C
C
3v3OUT
30
13
V
C
C
I
O
0.1uF
A
V
C
C
USB DM
USB DP
1k5
5
RSTOUT#
VCC
VCC
4
RESET#
+
0.1uF
0.1uF
10uF
G
N
D
A
G
N
D
G
N
D
9
17
29
Decoupling Capacitors
Figure 7 illustrates a typical USB bus powered configuration. A USB Bus Powered device gets its power from the USB
bus. Basic rules for USB Bus power devices are as follows –
a) On plug-in, the device must draw no more than 100mA
b) On USB Suspend the device must draw no more than 500uA.
c) A Bus Powered High Power Device (one that draws more than 100mA) should use the PWREN# pin to keep the
current below 100mA on plug-in and 500uA on USB suspend.
d) A device that consumes more than 100mA can not be plugged into a USB Bus Powered Hub
e) No device can draw more that 500mA from the USB Bus.
The power descriptor in the EEPROM should be programmed to match the current draw of the device.
A Ferrite Bead is connected in series with USB power to prevent noise from the device and associated circuitry (EMI)
being radiated down the USB cable to the Host. The value of the Ferrite Bead depends on the total current required by
the circuit – a suitable range of Ferrite Beads is available from Steward (www.steward.com) for example Steward Part
# MI0805K400R-00 also available as DigiKey Part # 240-1035-1.
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 17 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
Figure 8
USB Self Powered Configuration
USB "B"
Connector
470R
VCC
1
27R
2
3
4
3
FT245BM
27R
6
33nF
26
V
C
C
V
C
C
3v3OUT
30
13
V
C
C
I
O
0.1uF
A
V
C
C
4k7
8
7
10k
USB DP
1k5
5
4
VCC
0.1uF
RSTOUT#
RESET#
G
N
D
+
0.1uF
USB DM
10uF
A
G
N
D
G
N
D
9
17
29
Decoupling Capacitors
Figure 8 illustrates a typical USB self powered configuration. 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 power devices are as
follows –
a) A Self-Powered device should not force current down the USB bus when the USB Host or Hub Controller is
powered down.
b) A Self Powered Device can take as much current as it likes during normal operation and USB suspend as it has its
own POWER SUPPLY.
c) A Self Powered Device can be used with any USB Host and both Bus and Self Powered USB Hubs
The USB power descriptor option in the EEPROM should be programmed to a value of zero (self powered).
To meet requirement a) the 1.5K pull-up resistor on USBDP is connected to RSTOUT# as per the bus-power circuit.
However, the USB Bus Power is used to control the RESET# Pin of the FT245BQ device. When the USB Host or
Hub is powered up RSTOUT# will pull the 1.5K resistor on USB DP to 3.3V, thus identifying the device 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, RSTOUT# will also be low, so no current will be forced down USBDP via the 1.5K pull-up resistor
when the host or hub is powered down. Failure to do this may cause some USB host or hub controllers to power up
erratically.
Note : When the FT245BQ is in reset, the FIFO interface pins all go tri-state. These pins have internal 200K pull-up
resistors to VCCIO so they will gently pull high unless driven by some external logic.
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 18 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
Figure 9
Bus Powered Circuit with 3.3V logic drive / supply voltage
3.3v LDO Regulator
In
3.3v Power to External
Logic
Out
Gnd
0.1uF
USB "B"
Connector
Ferrite Bead
1
470R
VCC
27R
2
3
3
V
C
C
27R
4
10nF
26
6
33nF
13
V
C
C
3v3OUT
V
C
C
I
O
30
0.1uF
A
V
C
C
FT245BM
8
7
USB DM
USB DP
Figure 9 shows how to configure the FT245BQ to interface with a 3.3V logic device. In this example, a discrete
3.3V regulator is used to supply the 3.3V logic from the USB supply. VCCIO is connected to the output of the 3.3V
regulator, which in turn will cause the FIFO interface IO pins to drive out at 3.3V level. For USB bus powered circuits
some considerations have to be taken into account when selecting the regulator –
a) The regulator must be capable of sustaining its output voltage with an input voltage of 4.35 volts. A Low Drop Out
(LDO) regulator must be selected.
b) The quiescent current of the regulator must be low in order to meet the USB suspend total current requirement of
<= 500uA during USB suspend.
An example of a regulator family that meets these requirements is the MicroChip (Telcom) TC55 Series. These
devices can supply up to 250mA current and have a quiescent current of under 1uA.
In some cases, where only a small amount of current is required (< 5mA) , it may be possible to use the in-built
regulator of the FT245BQ to supply the 3.3V without any other components being required. In this case, connect
VCCIO to the 3V3OUT pin of the FT245BQ.
Note : It should be emphasised that the 3.3V supply for VCCIO in a bus powered design with a 3.3V logic interface
should come from an LDO which is supplied by USB bus, or from the 3V3OUT pin of the FT245BQ, and not from any
other source.
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 19 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
Figure 10
Self Powered Circuit with 3.3 V logic drive / supply voltage
VCC3V
USB "B"
Connector
470R
1
2
27R
3
0.1uF
27R
4
33nF
30
3
13
26
V
C
C
A
V
C
6
C
3v3OUT
V
C
C
V
C
C
I
O
FT245BM
4K7
8
7
10K
USB DM
USB DP
VCC3V
1K5
5
4
VCC5V
0.1uF
SI/WU
RSTOUT#
RESET#
G
N
D
+
0.1uF
VCC5V
10uF
A
G
N
D
G
N
D
9
11
17
29
Decoupling Capacitors
Figure 10 is an example of a USB self powered design with 3.3V interface. In this case VCCIO is supplied by an
external 3.3V supply in order to make the device IO pins drive out at 3.3V logic level, thus allowing it to be connected
to a 3.3V MCU or other external logic. A USB self powered design uses its own power supplies, and does not draw
any of its power from the USB bus. In such cases, no special care need be taken to meet the USB suspend current
(0.5 mA) as the device does not get its power from the USB port.
As with bus powered 3.3V interface designs, in some cases, where only a small amount of current is required (<5mA),
it may be possible to use the in-built regulator of the FT245BQ to supply the 3.3V without any other components being
required. In this case, connect VCCIO to the 3v3OUT pin of the FT245BQ.
Note that if SI/WU is not being used it should be pulled up to VCCIO.
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 20 of 24
Figure 11
Bus Powered Circuit with Power Control
FT245BQ USB FIFO ( USB - Parallel ) I.C.
P-Channel Power
MOSFET
s
Switched 5v Power to
External Logic
d
0.1uF
0.1uF
Soft Start
Circuit
1K
g
USB "B"
Connector
Ferrite Bead
1
2
470R
VCC
27R
3
4
3
V
C
C
27R
10nF
26
6
33nF
13
V
C
C
3v3OUT
V
C
C
I
O
30
0.1uF
A
V
C
C
FT245BM
8
7
USB DM
PWREN#
15
USB DP
USB Bus powered circuits need to be able to power down in USB suspend mode in order to meet the <= 500uA total
suspend current requirement (including external logic). Some external logic can power itself down into a low current
state by monitoring the PWREN# pin. For external logic that cannot power itself down in that way, the FT245BQ
provides a simple but effective way of turning off power to external circuitry during USB suspend.
Figure 11 shows how to use a discrete P-Channel Logic Level MOSFET to control the power to external logic
circuits. A suitable device could be a Fairchild NDT456P, or International Rectifier IRLML6402, or equivalent. It is
recommended that a “soft start” circuit consisting of a 1K series resistor and a 0.1 uF capacitor are used to limit the
current surge when the MOSFET turns on. Without the soft start circuit there is a danger that the transient power
surge of the MOSFET turning on will reset the FT245BQ, or the USB host / hub controller. The values used here
allow attached circuitry to power up with a slew rate of ~12.5 V per millisecond, in other words the output voltage will
transition from GND to 5 V in approximately 400 microseconds.
Alternatively, a dedicated power switch I.C. with inbuilt “soft-start” can be used instead of a MOSFET. A suitable
power switch i.c. for such an application would be a Micrel (www.micrel.com) MIC2025-2BL or equivalent.
Please note the following points in connection with power controlled designs –
a) The logic to be controlled must have its own reset circuitry so that it will automatically reset itself when power is reapplied on coming out of suspend.
b) Set the Pull-down on Suspend option in the FT245BQ’s EEPROM.
c) For USB high-power bus powered device (one that consumes greater than 100 mA, and up to 500 mA of current
from the USB bus), the power consumption of the device should be set in the max power field in the EEPROM.
A high-power bus powered device must use this descriptor in the EEPROM to inform the system of its power
requirements.
d) For 3.3V power controlled circuits VCCIO must not be powered down with the external circuitry (PWREN# gets
its VCC supply from VCCIO). Either connect the power switch between the output of the 3.3V regulator and the
external 3.3V logic OR if appropriate power VCCIO from the 3v3OUT pin of the FT245BQ.
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 21 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
Figure 12
Microprocessor Interface Example
Microcontroller
FT245BM
D2
D3
D4
D5
D6
D7
RD#
WR
TXE#
RXF#
SI / WU
IO10
24
IO11
23
IO12
22
IO13
21
IO14
20
IO15
19
IO Port 1
D1
25
IO16
18
IO17
16
IO20
15
IO21
14
IO22
12
IO23
11
( Optional )
IO Port 2
D0
IO24
Figure 12 illustrates a typical interface between the FT245BQ and a MicroController (MCU). This examples uses two
IO Ports of the MCU, one port (8 bits) to transfer data and the other port (4 / 5 bits) to monitor the TXE# and RXF#
status bits and generate the RD# and WR strobes to the FT245BQ as required. Optionally, SI / WU can be connected
to another IO pin if this function is required. If the SI / WU function is not required, tie this pin of the FT245BQ to
VCCIO. If the MCU is handling power management functions, then PWREN# should also be connected to an IO pin of
the MCU.
The 8 data bits of Port 1 can be shared with other peripherals when the MCU is not accessing the FT245BQ.
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
Page 22 of 24
FT245BQ USB FIFO ( USB - Parallel ) I.C.
8.0 Document Revision History
DS245B Version 1.0 – Initial document created 8th August 2002.
DS245B Version 1.1 – Updated 23 October 2003
•
Pin and package naming made consistent throughout data sheet.
•
Section 1.0 Corrected data transfer rate for VCP drivers.
•
Section 1.0 Amended to reflect availability of Mac OS X drivers.
•
Section 1.1 Description of behaviour of TXE# and RXF# amended.
•
Section 3.1 Minor changes to functional block descriptions.
•
Section 2.0 Compatible EEPROM configurations corrected.
•
Section 4.1 SI/WU Pin description amended.
•
Section 4.1 RSTOUT# Pin description amended.
•
Section 4.1 EEPROM interface Pin descriptions amended.
•
Section 4.1 Note 2 should have referred to VCCIO, not VCC.
•
Section 4.1 FIFO timing diagram amended.
•
Section 6.1 Minimum Operating supply voltage adjusted.
•
Section 7.1 Updated recommended ceramic resonator part number and circuit configuration.
•
Section 7.3 “USB Self Powered Configuration (1)” (original Figure 8) removed. Recommended circuit for USB self powered designs updated.
•
Section 7.3 Self Powered Circuit with 3.3V logic drive / supply voltage added (new figure 8).
•
Section 7.3 Figure 11 Bus powered circuit with power control updated to add soft start circuit on MOSFET. Circuit description amended.
DS245B Version 1.2 – Updated 20 November 2003.
•
Section 6.1 FIFO Data control Bus IO pin characteristics amended
•
Section 6.1 RESET#, TEST, EECS, EESK, and EEDATA pin characteristics amended.
•
Section 6.1 RSTOUT# pin characteristics amended.
DS245B Version 1.3 – Updated 10 December 2003
•
Section 5.0 Package drawing amended.
•
Section 6.0 Floor Life / Relative Humidity specification added. ESD and Latch Up specifications amended.
•
Section 7.1 Required accuracy of crystal / resonator corrected.
DS245B Version 1.4 – Updated 10 February 2004
•
Grammar Corrections.
•
Section 10.0 FTDI Address Updated
•
Section 4.1 VCCIO Pin description ammended.
DS245B Version 1.5 – Updated March 2004
•
Section 4.1 FIFO EESK Pin Description amended.
•
Section 4.1 FIFO WR timings and diagram amended.
•
Section 7.3 Figure 10 SI/WU Pin number corrected
•
Section 7.3 Figure 11 PWREN# Pin number corrected
DS245B Version 1.6 – Updated February 2005
•
Section 1 - Win CE VCP drivers now available
•
Section 1 - D2XX drivers for Win CE and Linux now available
•
Section 5 FT245BQ (lead free) and FT245BQ (lead free QFN package) now available
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
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FT245BQ USB FIFO ( USB - Parallel ) I.C.
9.0 Disclaimer
© Future Technology Devices International Limited , 2002 - 2004
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.
10.0 Contact Information
Future Technology Devices Intl. Limited
373 Scotland Street
Glasgow G5 8QB,
United Kingdom.
Tel : +44 ( 0 )141 429 2777
Fax : +44 ( 0 )141 429 2758
E-Mail ( Sales ) : [email protected]
E-Mail ( Support ) : [email protected]
E-Mail ( General Enquiries ) : [email protected]
Web Site URL : http://www.ftdichip.com
Agents and Sales Representatives
At the time of writing our Sales Network covers over 40 different countries world-wide. Please visit the Sales Network
page of our Web Site for the contact details our distributor(s) in your country.
See : http://www.ftdichip.com/FTDisti.htm
DS245BQ Version 1.6
© Future Technology Devices Intl. Ltd. 2005
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