1.1 Transmitter

High-speed transmitter has the following adjustable capabilities:

  • Amplitude: Transmitter supports 10 amplitude settings from 100 mV to 1000 mV in steps of 100 mV.
  • De-emphasis: Transmitter supports six de-emphasis settings. Those are 0 dB, –1 dB, –2.5 dB, –3.5 dB, –4.4 dB and –6 dBmV.
  • Termination impedance: Transmitter supports four driver terminations. Those are 85Ω, 100Ω, 150Ω and 180Ω.
  • Jitter: In the IBIS-AMI simulation, the following Jitter parameters can be used for the transmitter:
    • Tx_DCD (Tx duty cycle distortion)
    • Tx_Dj (Tx deterministic jitter)
    • Tx_Rj (Tx random jitter)
    Important:
    • Transmitter tuning alone does not help for high loss channel, receiver tuning is also required to make system work without errors.
    • For the worst-case jitter numbers, see PolarFire Mid-Range FPGAs. By default, these jitter numbers are considered while running IBIS-AMI simulations.

The following table describes the recommended Tx settings for different channel lengths.

Table 1-1. Recommended Driver Amplitude, De-emphasis and Impedance Settings
Amplitude and De-emphasis Setting (mV with dB)Tx Termination (Ω)Recommended Channel
100 mV with 0 dB100Very short
200 mV with 0 dB100Very short
200 mV with –1 dB100Very short
200 mV with –2.5 dB100Very short
200 mV with –3.5 dB100Very short
200 mV with –4.4 dB100Very short
200 mV with –6 dB100Very short
300 mV with 0 dB100Short
400 mV with 0 dB100Short
400 mV with –1 dB100Short
400 mV with –2.5 dB100Short
400 mV with –3.5 dB100Short
400 mV with –4.4 dB100Short
400 mV with –6 dB100Short
500 mV with 0 dB100Short
600 mV with –3.5 dB150Short/Medium
600 mV with –6 dB150Short/Medium
800 mV with 0 dB150Short/Medium/Long
800 mV with –1 dB150Short/Medium/Long
800 mV with –2.5 dB150Short/Medium/Long
800 mV with –3.5 dB150Short/Medium/Long
800 mV with –4.4 dB150Short/Medium/Long
800 mV with –6 dB150Short/Medium/Long
1000 mV with 0 dB180Short/Medium/Long
1000 mV with –1 dB180Short/Medium/Long
1000 mV with –2.5 dB180Short/Medium/Long
1000 mV with –3.5 dB180Short/Medium/Long
1000 mV with –4.4 dB180Short/Medium/Long
1000 mV with –6 dB180Short/Medium/Long
Important: Apart from the recommended settings in the preceding table, each driver termination (85Ω, 100Ω, 150Ω and 180Ω) has 29 amplitude and emphasis settings ranging from 100 mV with 0 dB to 1000 mV with –6 dB. You can apply any of the recommended or other settings to the silicon according to their applications.