Quad PCI Express Equalizer/Redriver

Ultra-Small Equalizer/Redriver Improves PCIe Signal Integrity Across Systems

Please check latest availability status for a specific part variant.


The MAX4950 PCI Express (PCIe®) quad equalizer/redriver operates from a single +3.3V supply. This device improves signal integrity at the receiver through programmable input equalization and programmable redrive circuitry. The output circuitry reestablishes deemphasis lost on the board, compensating for circuit board loss. This device permits optimal placement of key PCIe components and longer runs of stripline, microstrip, or cable.

The MAX4950 contains four identical buffers capable of equalizing differential signals at data rates up to 5GT/s, and features electrical idle and receiver detection on each channel. The MAX4950 is ideal for use with PCIe Gen I (2.5GT/s) and Gen II (5.0GT/s) data rates and features a power-saving mode.

The MAX4950 is available in a small, lead-free, 42-pin (3.5mm x 9.0mm) TQFN package for optimal layout and minimal space requirements. The board traces are flow-through for ease of layout. The MAX4950 is specified over the 0°C to +70°C operating temperature range.
MAX4950: Typical Application Diagram MAX4950: Typical Application Diagram Enlarge+

Key Features

  • Single +3.3V Supply Operation
  • Generation I (2.5GT/s) and Generation II (5.0GT/s) Capable
  • Return Loss:
    • ≥ 10dB (f ≤ 1.25GHz)
    • ≥ 8dB (f ≤ 2.5GHz)
  • Very Low Latency
    • 280ps Propagation Delay
  • Individual Lane Detection
  • Low Lane-to-Lane Skew: ±50ps
  • Total Jitter ≤ 35psP-P at BER = 10-12
  • Three-Level-Programmable Input Equalization
  • Three-Level-Programmable Output Deemphasis
  • On-Chip 50Ω Input/Output Terminations
  • ±2kV Human Body Model (HBM) Protection on All Pins
  • Space-Saving, 3.5mm x 9.0mm, TQFN Packaging


  • Communication Switchers
  • Desktop Computers
  • Industrial PCs
  • Laptop Computers (for External Video Cards)
  • Servers
  • Storage Area Networks
  • Test Equipment

Technical Documents

App Note 4653 FAQs about Analog Switches

Quality and Environmental Data

Product Reliability Reports: MAX4950.pdf 
Lead-Free Package Tin (Sn) Whisker Reports

Tools & Models

  • MAX4950 HSPICE Model
  • Device   Fab Process   Technology   Sample size   Rejects   FIT at 25°C   FIT at 55°C  

    Note : The failure rates are summarized by technology and mapped to the associated material part numbers. The failure rates are highly dependent on the number of units tested.

    Quality Management System >
    Environmental Management System >


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