FAQs

Find answers to the most frequently asked questions about our products and technologies.

What are the new specifications in PCIe 5.0?

  1. CTLE & DFE: PCIe 5.0 specifies the bump-to-bump IL budget as 36 dB for 32 GT/s, and the bit error rate (BER) must be less than 10-12. To address the problem of high attenuation to the signal, the PCIe 5.0 standard defines the reference receiver such that the continuous-time linear equalizer (CTLE) model includes an ADC (adjustable DC gain) as low as -15 dB, whereas the reference receiver for 16 GT/s is only -12 dB. The reference decision feedback equalizer (DFE) model includes three taps for 32 GT/s and only two taps for 16 GT/s.
  2. Precoding: Due to the significant role of the DFE circuit plays in the receiver’s overall equalization, burst errors are more likely to occur compared to 16 GT/s. To counteract this risk, PCIe 5.0 introduces Precoding in the protocol. After enabling precoding at the transmitter side and decoding at the receiver side, the chance of burst errors is greatly reduced, thereby enhancing the robustness of the PCIe 5.0 32 GT/s Link.