GS1575B Datasheet, PDF (20/28 Pages) Gennum Corporation – HD-LINX II Multi-Rate SDI Automatic Reclocker

In Manual mode, the SS[2:0] pins become inputs and the data rate can be programmed
by the application layer. In this mode, the search algorithm is disabled and the PLL will
only lock to the data rate selected.
Table 4-2 shows the SS[2:0] pin settings for either the data rate selected (in Manual
mode) or the data rate that the PLL has locked to (in Auto mode).
Table 4-2: Data Rate Indication/Selection Bit Pattern
SS[2:0]
Data Rate (Mb/s)
000
143
001
177
010
270
011
360
100
540
101*
1485/1483.5
* This setting only applies to the GS1575B. For the GS9075B, when AUTO/MAN is LOW, the pin
settings SS[0:2] = 101 will be ignored by the device.
4.8 Bypass Mode
In Bypass mode, the GS1575B/9075B passes the data at the inputs directly to the outputs.
There are two pins that control the bypass function: BYPASS and AUTOBYPASS.
When BYPASS is set HIGH by the application layer, the GS1575B/9075B will be in
Bypass mode.
When AUTOBYPASS is set HIGH by the application layer, the GS1575B/9075B will be
configured to enter Bypass mode only when the PLL has not locked to a data rate. When
BYPASS is set HIGH, AUTOBYPASS will be ignored.
When the PLL is not locked, and both BYPASS and AUTOBYPASS are set LOW, the serial
digital output DDO/DDO will produce invalid data.
GS1575B / GS9075B HD-LINX® II Multi-Rate SDI
Automatic Reclocker
Data Sheet
40063 - 1
June 2009
20 of 28