Ds160Pr412 And Ds160Pr421 Equalization Control; Ds160Pr412 And Ds160Pr421 Rx Detect State Machine; Table 2-4. Equalization Control Settings - Texas Instruments DS160PR412-421EVM User Manual

www.ti.com

2.4 DS160PR412 and DS160PR421 Equalization Control

Each channel of the DS160PR412 and DS160PR421 features a continuous-time linear equalizer (CTLE) that
applies high-frequency boost and low-frequency attenuation to help equalize the frequency-dependent insertion
loss effects of the passive channel.
and EQ0) for all channels when in Pin Control mode (MODE = L0).
EQ INDEX EQ1 PIN LEVEL
0 L0
1 L0
2 L0
3 L0
4 L1
5 L1
6 L1
7 L1
8 L2
9 L2
10 L2
11 L2
12 L3
13 L3
14 L3
15 L3
The equalization gain of each channel of each device can also be set by writing to SMBus / I2C registers in I2C
Mode. See the DS160PR412, DS160PR421 Programming Guide

2.5 DS160PR412 and DS160PR421 RX Detect State Machine

Each DS160PR412 and DS160PR421 deploys an RX Detect state machine that governs the RX detection cycle
as defined in the PCI Express specification. At power up or after a manually triggered event, the redriver
determines whether or not a valid PCI Express termination is present at the far end of the link. The
RX_DET/SCL pin of DS160PR412 and DS160PR421 provides additional flexibility to system designers to
appropriately set the device in their desired mode, according to
SNLU288 – DECEMBER 2020
Submit Document Feedback
Table 2-4 shows available equalization boost through EQ control pins (EQ1

Table 2-4. Equalization Control Settings

EQ0 PIN LEVEL CTLE BOOST AT 4 GHz (dB)
L0
L1
L2
L3
L0
L1
L2
L3
L0
L1
L2
L3
L0
L1
L2
L3
Copyright © 2020 Texas Instruments Incorporated
CTLE BOOST AT 8 GHz (dB)
–0.25
2.0
2.5
3.0
4.0
4.5
5.0
6.0
7.0
8.0
8.5
9.0
9.5
10.0
10.5
12
for details.
Table 2-5.
DS160PR412-421EVM Evaluation Module
Description
–0.5
4.0
5.0
6.0
7.0
7.5
8.0
9.5
10
11
12.5
13
14.5
15
16.0
18
5