GS1535 Data Sheet
Table 1-1: Pin Descriptions (Continued)
Pin
Name
Type
Description
Number
24, 25, 26
SS[2:0]
BIDIRECTIONAL
When AUTO/MAN is HIGH, SS[0:2] are outputs, displaying the data rate to
which the PLL has locked.
When AUTO/MAN is LOW, SS[0:2] are inputs, forcing the PLL to lock only to a
selected data rate.
SS2
SS1
SS0
DATA RATE
SELECTED/FORCED (Mb/s)
0
0
0
0
1
1
0
0
1
1
0
0
0
1
0
1
0
1
143
177
270
360
540
1483.5/1485
27
ASI/177
LOGIC INPUT
Disables 177Mbps data rate in the AUTO data rate detection circuit. This
prevents a FALSE LOCK to 177Mbps when using DVB/ASI.
28
29
33
LD
OUTPUT
RESERVED
OUTPUT
LOCK DETECT. HIGH when the PLL is locked.
DO NOT CONNECT.
RSVD
SD/HD
This signal is LOW when the reclocker has locked to 1.485Gbps or
1.485/1.001Gbps, and HIGH when the reclocker has locked to 143Mbps,
177Mbps, 270Mbps, 360Mbps, or 540Mbps.
34
KBB
ANALOG INPUT
Controls the loop bandwidth of the PLL. Leave this pin floating for serial
reclocking applications.
36
DDO_MUTE
DDO, DDO
DDO_VTT
LOGIC INPUT
OUTPUT
Mutes the DDO/DDO outputs, when not in bypass mode.
Differential Serial Digital Outputs.
44, 46
45
PASSIVE
Center tap of two 50Ω on-chip termination resistors between DDO and DDO..
Differential buffered outputs of the reference oscillator.
50, 51
XTAL_OUT+,
XTAL_OUT-
OUTPUT
52, 53
62, 63
XTAL+, XTAL-
LF+, LF-
INPUT
Reference crystal input. Connect to the GO1535.
Loop filter capacitor connection. (CLF = 47nF).
PASSIVE
4, 8, 12,16,
32, 35, 37,
GND
PASSIVE
PASSIVE
Recommended connect to GND.
43, 49, 54, 64
43
GND_DRV
Recommended connect to GND.
18557 - 8 February 2005
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