VITESSE
SEMICONDUCTOR CORPORATION
Data Sheet
Multi-Rate SONET/SDH
Clock and Data Recovery IC
VSC8122
Table 8: Pin Identifications
Pin #
Name
I/O
Level
Description
Selectable input rate pin 0
Selectable input rate pin 1
1
2
3
4
5
6
7
8
9
FSEL0
FSEL1
I
I
TTL
TTL
TTL
—
REF_INPUTSEL
NC
I
Toggle between REFCK1 and REFCK0
No connect, leave unconnected(1)
—
I
VEE_ANA
VCC_ANA
NC
GND typ. Negative power supply pins for analog parts of CMU
+3.3V typ. Positive power supply pins for analog parts of CMU
I
—
—
O
—
—
No connect, leave unconnected
No connect, leave unconnected
Loss of lock indication
NC
LOL
TTL
No reference output. Active HIGH for REFCK far off the
expected frequency.
10
NOREF
O
TTL
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
VCC
FILTAO
FILTAI
FILTAIN
FILTAON
VEE
VCC
NC
I
I
+3.3V typ. Positive power supply
—
—
—
—
Loop filter pin - connect via capacitor to FILTAI
I
Loop filter pin - connect via capacitor to FILTAO
Loop filter pin - connect via capacitor to FILTAON
Loop filter pin - connect via capacitor to FILTAIN
I
I
I
GND typ. Negative power supply
+3.3V typ. Positive power supply
I
—
—
—
—
—
—
I
—
—
—
—
—
—
No connect, leave unconnected(1)
NC
No connect, leave unconnected(1)
No connect, leave unconnected(1)
No connect, leave unconnected(1)
No connect, leave unconnected(1)
No connect, leave unconnected(1)
NC
NC
NC
NC
VCC
VEE
VCC
CO-
+3.3V typ. Positive power supply
GND typ. Negative power supply
+3.3V typ. Positive power supply
I
I
O
O
I
HS
HS
High-speed clock output, complement
High-speed clock output, true
CO+
VCC
VEE
VCC
NC
+3.3V typ. Positive power supply
GND typ. Negative power supply
+3.3V typ. Positive power supply
I
I
—
—
—
—
—
—
No connect, leave unconnected(1)
No connect, leave unconnected(1)
No connect, leave unconnected(1)
NC
NC
© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012
Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com
Internet: www.vitesse.com
G52228-0, Rev 4.1
01/05/01
Page 9
VITESSE [ VITESSE SEMICONDUCTOR CORPORATION ]
