Example 4: An on-board type HUB with a COM20020 and four optical transceivers in backplane mode.
+5V
1
OUT
2
GND1
3
VCC1
TODX270A
TODX270A
TODX270A
TODX270A
4
5
6
7
8
GND2
GND3
LEDR
VCC2
IN
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
RXINA0
SA
TXENA0
LA
RXINA1
VSS5
VSS3
AVSS
AGS
LP
RO
AVDD
VDD3
VDD4
VSS4
XTLO
XTLI
VDD2
nPLLTST
RXFLT
MA
TXENA1
VDD6
VSS8
RXINB0
SB
TXENB0
LB
RXINB1
MB
TMC2005
1
2
3
4
5
6
7
8
OUT
GND1
VCC1
GND2
GND3
LEDR
VCC2
IN
1
2
3
4
5
6
OUT
GND1
VCC1
GND2
GND3
LEDR
VCC2
7
8
IN
1
2
3
4
5
6
OUT
GND1
VCC1
GND2
GND3
LEDR
VCC2
7
8
IN
15
18
1
2
nPULSE1
3
nTXEN
COM20020
17
RXIN
FIGURE 4 - APPLICATION EXAMPLE 4
Only the TMC2005 and four transceivers with the COM20020 are indicated in the above figure. Connect the other
pins adequately.
SMSC DS – TMC2005
Page 16
Rev. 10/24/2000
SMSC [ SMSC CORPORATION ]
