GX4002 Datasheet, PDF (19/74 Pages) Gennum Corporation – Dynamic on-chip power management control

3.3 Channel 1 Path (Ch1)
The GX4002 channel 1 path contains a high-sensitivity limiting amplifier with optional
equalization, a multi-rate CDR, and a pre-emphasis driver.
Ch1 LOS
Input
LA
CDR
DR
Output
Chip Control & Status
I² C
Figure 3-2: Channel 1 Path
3.3.1 Integrated Limiting Amplifier
The GX4002 has an integrated Limiting Amplifier (LA), with better than 10mV
sensitivity. Optional equalization is available on the limiting amplifier input.
3.3.2 Ch1 Equalization
The channel 1 input implements an equalizer that provides peaking at 7GHz. This
feature allows for optimal performance with extended reach connections.
The equalizer implements 0dB to 14dB of high-frequency boost in fifteen steps, while
achieving optimal receive sensitivity at any given equalization setting. The equalization
setting is set through the CH1LABOOST control.
Register Name
CH1_REG1
Register
Address^d
48
Parameter Name
CH1LABOOST
Bit
Position
3:0
Access
RW
Reset Value^b
0000
Valid
Range^d
Function
0-15
0: 0dB to 15: 14dB.
GX4002 2x2 14.025Gb/s Crosspoint Switch with Trace
Equalization and Output De-Emphasis
Data Sheet
55972 - 0
March 2012
19 of 74
Proprietary & Confidential