GS3590 datasheet(23/118 Pages) SEMTECH

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GS3590

Final Data Sheet Rev.4



PDS-061414 September 2017

23 of 118

Semtech

Proprietary & Confidential

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4.3 Trace Equalizer

The GS3590 features a differential input buffer with 100Ω differential input termination,

which includes a Trace Equalizer that can be configured to compensate for up to 60" of

7mil strip-line in FR4 at 2.97Gb/s.

Note: The parameters referred to within Section 4.3 to Section 4.3.2 are linked to their

respective registers in Table 4-2.

The differential input signal can be either DC-coupled or AC-coupled, and is capable of

operation with any binary coded signal between 1Mb/s and 2.97Gb/s.

The input circuit is compatible with industry standard CML differential transmitters

when DC-coupled using industry standard 100Ω differential termination circuitry.

The Trace Equalizer includes an automatic input offset compensation circuit. This

reduces offset-induced data jitter in the link due to asymmetric performance of

DC-coupled upstream differential drivers. The input offset compensation circuit also

improves the input sensitivity of the Trace Equalizer.

4.3.1 Input Trace Equalization

The Trace Equalizer can compensate for up to 17dB of insertion loss at 1.485GHz in 8

increments, which can be adjusted through the CFG_TREQ0_BOOST parameter in

control register 0x1E. The default value of CFG_TREQ0_BOOST is (0h), which

corresponds to the minimum equalization boost level.

Please refer to Figure 4-2 for recommended boost setting.

Figure 4-2: GS3590 Trace EQ Boost Setting Recommendation

1011121314151617

Insertion Loss at 1.485GHz (dB)

boost setting 8

boost setting 7

boost setting 6

boost setting 5

boost setting 4

boost setting 3

boost setting 2

boost setting 1

boost setting 0

GS3590 Datasheet(PDF) 23 Page - Semtech Corporation