GS2986 datasheet(22/41 Pages) SEMTECH

22 / 41 page

GS2986 Multi-Rate SDI Reclocker with Equalization &

De-emphasis

Data Sheet

52134 - 3

July 2012

22 of 41

Figure 4-2: De-emphasis Waveform

4.10 Automatic and Manual Data Rate Selection

The GS2986 can be configured to manually lock to a specific data rate or automatically search

for and lock to the incoming data rate. The default configuration is AUTO mode. This can be

changed via the host interface.

In AUTO mode, the SS[1:0] registers become read only, and the bit pattern indicates the data rate

at which the PLL is currently locked to (or previously locked to). The search algorithm cycles

through the data rates and starts over if that data rate is not found (see Figure 4-3).

A “search algorithm” cycles through the supported data rates until lock is achieved, as shown in

Figure 4-3 below.

Figure 4-3: GS2986 Automatic Mode Search Algorithm

In MANUAL mode, the SS[1:0] registers become read or write pins become inputs and the data

rate can be programmed. In this mode, the search algorithm is disabled and the GS2986's PLL

-V1

-V2

Tx signal after de-emphasis

11110000 pattern

268

269

270

271

272

273

274

275

-0.6

-0.4

-0.2

0.2

0.4

0.6

De-emphasis (dB)

=20 log (V1/V2)

Power up

270Mb/s

1485Mb/s

2970Mb/s

*Note: the search algorithm does not necessarily begin with 270Mb/s.

GS2986 데이터시트(PDF) 22 Page - Semtech Corporation

GS2986 데이터시트(HTML) 22 Page - Semtech Corporation

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41

데이터시트 다운로드

링크 URL