Highlights
  • External PCIe (SFF-8644 1x2) to PCIe x8 Gen 4 Active (Redriver with Linear Equalization) Cable Adapter
    • PCIe x8 Edge Finger
    • Redriver with Linear Equalization support PCIe Gen 1.0, 2.0, 3.0, 4.0
    • External PCIe Cable Port (SFF-8644 1x2 Connector)
      • 4-Lane External PCIe Application: Mini SAS HD 4x Cable
      • 8-Lane External PCIe Application: Two Mini SAS HD 4x Cables or One Mini SAS HD 8x Cable
Introduction

EPCIE8XG4RDCA02 is External PCIe (SFF-8644 1x2) to PCIe x8 Gen 4 Active (Redriver with Linear Equalization) Cable Adapter, it requires no additional software or drivers to operate.

EPCIE8XG4RDCA02 is designed with Eight-Channel PCIe 4.0 Linear Redrivers to support PCIe Gen 1.0, 2.0, 3.0, 4.0.

The Eight-Channel PCIe 4.0 Linear Redriver deploy continuous time linear equalizers (CTLE) to provide a high-frequency boost. The equalizer can open an input eye that is completely closed due to inter-symbol interference (ISI) induced by an interconnect medium, such as PCB traces.

The linear redriver along with the passive channel as a whole get link trained for best transmit and receive equalization settings resulting in best electrical link and lowest possible latency. The linear redriver along with the passive channel as a whole get link trained for best transmit and receive equalization settings resulting in best electrical link and lowest possible latency. Low channel-channel cross-talk, low additive jitter and excellent return loss allows the device to become almost a passive element in the link. The devices has internal linear voltage regulator to provide clean power supply for high speed datapaths that provides high immunity to any supply noise on the board.
Technical Specifications
Upstream PCIe Interface
  • PCIe x8 Edge Finger

Downstream PCIe Interface (CON1A, CON1B)
  • SFF-8644 1x2 Connector
    • 100ohm, 72pin
  • Each SFF-8644 Connector 4-lane PCI Express
    • PCIe Gen 1 (2.5 GT/s)
    • PCIe Gen 2 (5.0 GT/s)
    • PCIe Gen 3 (8.0 GT/s)
    • PCIe Gen 4 (16.0 GT/s)
  • SFF-8644 1x2 Fixed-Side Connectors Pinout
ReDriver Feature
  • Eight channel linear equalizer supporting PCIe 4.0 up to 16 Gbps
  • CTLE boosts up to 18 dB at 8 GHz
  • Automatic receiver detection for PCIe use cases
  • Protocol agnostic linear redriver allows seamless support for PCIe link training
  • Ultra-low latency of 90 ps
  • Low additive random jitter of 70 fs with PRBS data
  • Single 3.3-V supply
  • Low active power of 107 mW/channel
  • No heat sink required
  • Pin-strap or SMBus programming
Power On Switch (J1)
  • Power On Switch: JST compatible wafer 2pin (pitch=2.5mm) connector
    • For auto-switch ATX Power Supply you may use a cable (CB-00711) to join EPCIE8XG4RDCA02 and PCIEX16D11

Receiver Equalization
  • DC Gain Setting:
    • The default DC Gain is 0dB.
      For most PCIe systems the default DC Gain 0dB would be sufficient.
  • Equalization setting (SW1~SW2)
    • SW1: PCIe Tx0~7 Equalization Setting
      From PCIe Edge Connector (Side B) to ReDrivers (U1)
    • SW2: PCIe Rx0~7 Equalization Setting
      From SFF-8644 (CON1) to ReDrivers (U2)
Host / Target Mode
  • Host / Target Mode Selection (SW3-1 & SW3-2)
    • Install EPCIE8XG4RDCA02 (Host Mode) into PCIe Slot of Mainboard.
    • Install EPCIE8XG4RDCA02 (Target Mode) into PCIe Slot of Docking Board.
Receiver Detect State Machine Setting
  • RX-Detect: In Pin Mode L3 (Float)
    TX polls every ~150us until valid termination is detected.
    RX CM impedance held at Hi-Z until detection Reset by asserting PD0/1 high for 200us then low.
    Pre Detect: Hi-Z, Post Detect: 50Ω
WAKE# Setting
  • Pin1-2: Enable
  • Pin3-4: Disable
Computer Platform Requirements Desktop computer equipped with a PCIe 1.0/2.0/3.0/4.0 x8, x16 slot
Physical Dimensions
  • 64.4mm(H) x 96.3mm(L)
  • NW:56.7g (Unit Package:114.7g)
Optional Accessories
  • SFF-8674 Cable (CB-S0060)
  • Expansion Backplane (PCIEX16D11, PCIEX16D01)
  • JST Wafer 2pin Cable; Pitch=2.5mm, 26AWG, , L=30cm (CB-00711)
  • Low Profile PCI Bracket (S-BR-00248-16-1020)
Kit includes

EPCIE8XG4RDCA02

  • EPCIE8XG4RDCA02
  • Manual

EPCIE8XG4RDCA02Kx

  • 2*EPCIE8XG4RDCA02
  • x: Docking Board
    • A: PCIEX16D01
    • B: PCIEX16D11
  • CB-00711---JST Wafer 2pin Cable
  • Manual