FT245BL/TR FTDI, FT245BL/TR Datasheet - Page 20

• Manufacturer Part Number: FT245BL/TR
• Description: IC, USB FIFO INTERFACE, 480MBPS, LQFP-32
• Manufacturer: FTDI

Specifications of FT245BL/TR

• Usb Type: FIFO
• Usb Version: 1.1, 2.0
• Data Rate: 480Mbps
• No. Of Ports: 2
• Supply Voltage Range: 4.35V To 5.25V
• Operating Temperature Range: 0°C To +70°C
• Digital Ic Case Style: LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Figure 10
Self Powered Circuit with 3.3 V logic drive / supply voltage
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 FT245BL to supply the 3.3V without any other components being
required. In this case, connect VCCIO to the 3v3OUT pin of the FT245BL.
Note that if SI/WU is not being used it should be pulled up to VCCIO.
Connector
USB "B"
DS245BL Version 1.6
0.1uF
1
2
3
4
4K7
10K
0.1uF
VCC5V
Decoupling Capacitors
27R
+
27R
10uF
© Future Technology Devices Intl. Ltd. 2005
1K5
33nF
0.1uF
4
6
8
7
5
FT245BL USB FIFO ( USB - Parallel ) I.C.
3v3OUT
30
USB DM
USB DP
RSTOUT#
RESET#
A
V
C
C
470R
FT245BM
3
G
V
C
C
N
D
9
26
V
C
C
G
N
D
17
SI/WU
C
C
O
V
Page 20 of 24
I
13
G
29
A
N
D
VCC3V
VCC5V
11
VCC3V