Cyclone V Device Datasheet

ID 683801
Date 5/23/2023
Public
Document Table of Contents

Transmitter Pre-Emphasis Levels

The following table lists the simulation data on the transmitter pre-emphasis levels in dB for the first post tap under the following conditions:

  • Low-frequency data pattern—five 1s and five 0s
  • Data rate—2.5 Gbps

The levels listed are a representation of possible pre-emphasis levels under the specified conditions only and the pre-emphasis levels may change with data pattern and data rate.

Cyclone® V devices only support 1st post tap pre-emphasis with the following conditions:

  • The 1st post tap pre-emphasis settings must satisfy |B| + |C| ≤ 60 where |B| = VOD setting with termination value, RTERM = 100 Ω and |C| = 1st post tap pre-emphasis setting.
  • |B| – |C| > 5 for data rates < 5 Gbps and |B| – |C| > 8.25 for data rates > 5 Gbps.
  • (VMAX/VMIN – 1)% < 600%, where VMAX = |B| + |C| and VMIN = |B| – |C|.

Exceptions for PCIe* Gen2 design:

  • VOD setting = 50 and pre-emphasis setting = 22 are allowed for PCIe* Gen2 design with transmit de-emphasis –6dB setting (pipe_txdeemp = 1’b0) using Intel® PCIe* Hard IP and PIPE IP cores.
  • VOD setting = 50 and pre-emphasis setting = 12 are allowed for PCIe* Gen2 design with transmit de-emphasis –3.5dB setting (pipe_txdeemp = 1’b1) using Intel® PCIe* Hard IP and PIPE IP cores.

For example, when VOD = 800 mV, the corresponding VOD value setting is 40. The following conditions show that the 1st post tap pre-emphasis setting = 2 is valid:

  • |B| + |C| ≤ 60→ 40 + 2 = 42
  • |B| – |C| > 5→ 40 – 2 = 38
  • (VMAX/VMIN – 1)% < 600%→ (42/38 – 1)% = 10.52%

To predict the pre-emphasis level for your specific data rate and pattern, run simulations using the Cyclone® V HSSI HSPICE models.

Table 28.   Transmitter Pre-Emphasis Levels for Cyclone® V Devices
Intel® Quartus® Prime 1st Post Tap Pre-Emphasis Setting Intel® Quartus® Prime VOD Setting Unit
10 (200 mV) 20 (400 mV) 30 (600 mV) 35 (700 mV) 40 (800 mV) 45 (900 mV) 50 (1000 mV)
0 0 0 0 0 0 0 0 dB
1 1.97 0.88 0.43 0.32 0.24 0.19 0.13 dB
2 3.58 1.67 0.95 0.76 0.61 0.5 0.41 dB
3 5.35 2.48 1.49 1.2 1 0.83 0.69 dB
4 7.27 3.31 2 1.63 1.36 1.14 0.96 dB
5 4.19 2.55 2.1 1.76 1.49 1.26 dB
6 5.08 3.11 2.56 2.17 1.83 1.56 dB
7 5.99 3.71 3.06 2.58 2.18 1.87 dB
8 6.92 4.22 3.47 2.93 2.48 2.11 dB
9 7.92 4.86 4 3.38 2.87 2.46 dB
10 9.04 5.46 4.51 3.79 3.23 2.77 dB
11 10.2 6.09 5.01 4.23 3.61 dB
12 11.56 6.74 5.51 4.68 3.97 dB
13 12.9 7.44 6.1 5.12 4.36 dB
14 14.44 8.12 6.64 5.57 4.76 dB
15 8.87 7.21 6.06 5.14 dB
16 9.56 7.73 6.49 dB
17 10.43 8.39 7.02 dB
18 11.23 9.03 7.52 dB
19 12.18 9.7 8.02 dB
20 13.17 10.34 8.59 dB
21 14.2 11.1 dB
22 15.38 11.87 dB
23 12.67 dB
24 13.48 dB
25 14.37 dB
26 dB
27 dB
28 dB
29 dB
30 dB
31 dB