Document No.: FT_000060
FT4232H QUAD HIGH SPEED USB TO MULTIPURPOSE UART/MPSSE IC
Datasheet Version 2.09
Clearance No.: FTDI#78
6.2 USB Self Powered Configuration
Self Powered application example 1: Self powered configuration
+3.3V
+3.3V
+1.8V +1.8V +1.8V +3.3V +3.3V +3.3V +3.3V
100nF 100nF 100nF 100nF
100nF 100nF 100nF
GND GND GND GND GND GND GND
4.7uF 4.7uF 100nF 100nF
GND GND GND GND
+1.8V
+3.3V
Ext. Power Supply
LDO +3.3V
Vin Vout
GND
+3.3V
50
49
16
17
18
19
21
22
23
24
VREGIN
1
2
ADBUS0
ADBUS1
ADBUS2
ADBUS3
+1.8V
VREGOUT
GND
3.3uF
GND
ADBUS4
ADBUS5
ADBUS6
ADBUS7
100nF
GND
100nF
GND
GND
1
2
3
4
26
27
28
29
30
32
33
34
VBUS
D-
D+
BDBUS0
BDBUS1
BDBUS2
BDBUS3
BDBUS4
BDBUS5
7
8
DM
DP
GND
6
REF
4.7K
14
BDBUS6
BDBUS7
RESET#
0?
1K
GND
12K
38
39
40
41
43
44
45
46
10K
CDBUS0
CDBUS1
CDBUS2
CDBUS3
CDBUS4
CDBUS5
+3.3V
GND
GND
10K
10K
10K
CDBUS6
CDBUS7
63
62
61
EECS
EECLK
EEDATA
EECLK
EEDATA
48
52
53
54
55
57
58
59
DDBUS0
DDBUS1
DDBUS2
DDBUS3
DDBUS4
DDBUS5
+3.3V
2
OSCI
1
6
3
2
8
DDBUS6
DDBUS7
CS
ORG
D
SCL
VCC
Q
4
7
1
3
3
OSCO
TEST
93C46
60
36
PWREN#
SUSPEND#
2.2K
12MHz
13
DU
5
GND
27pF
GND
27pF
GND
GND
GND
Figure 6.3 Self Powered Configuration Example 1
Figure 6.3 illustrates the FT4232H in 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. In this example
an external power supply is used. This external supply is regulated to +3.3V.
Note that in this set-up, the EEPROM should be configured for self-powered operation.
Copyright © 2010 Future Technology Devices International Limited
31
FTDI [ FUTURE TECHNOLOGY DEVICES INTERNATIONAL LTD. ]
