8.5Gbps Quad Equalizer and Preemphasis Driver

Best-in-Class Redriver Can Equalize 25in to 30in of FR4


The MAX3987 is a 4-channel receive and transmit equalizer (EQ). It compensates for transmission medium losses encountered with FR4 stripline/microstrip and/or high-speed cable. The device can be used at the beginning, middle, or end of a channel. The input equalization requires no setting, and the output preemphasis (PE) is programmable.

For each channel, the preemphasis level, output drive level, output polarity, and powering down of unused outputs are programmable through an I²C serial interface. It can also be configured globally through pins.

The device operates from a 2.5V or 3.3V supply, and is packaged in a 7mm x 7mm, 48-pin TQFN.
MAX3987: Typical Application Circuit MAX3987: Typical Application Circuit Enlarge+

Key Features

  • Up to 8.5 NRZ Data Speed
  • Receive Equalization Up to 30in FR4
  • Preemphasis Drive Up to 30in FR4
  • Global and Individual Programming of Preemphasis, Output Drive Levels, Polarity Inversion, and Offset Cancellation
  • Signal Detect and Internal Output Squelch
  • Compliant with SAS-2 and SATA Revision 3 OOB
  • Coding Independent, 8B/10B, 64B/66B, Scrambled, and Others
  • Differential CML Data-Output Drive
  • I²C Serial Interface and Pin Programmable
  • Software Power-Down of Unused Outputs
  • 0.5W Typical Power Dissipation for Drive Level 1 at VCC = 2.5V
  • High-Performance, Lead-Free, 7mm x 7mm, 48-Pin TQFN Package


  • FR4 and Cable Equalization
  • PCIe® Compatible
  • Preemphasis and Receive Equalization
  • Redrive
  • XAUI and XAUI2, Fibre Channel, Interlaken, InfiniBandTM/SM, SAS-2 and SATA Revision 3 OOB
Part Number Applications Data Rate
Max. Reach @ Max. Data Rate VSUPPLY
I/O Type Channels Oper. Temp.
max See Notes
FR4 and Cable Equalization
PCIe® Compatible
Preemphasis and Receive Equalization
8500 30in FR4
CML 4 -40 to +85 $22.33 @1k
See All Equalizers (Cable and Circuit Board) (18)
Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

MAX3987EVKIT: Evaluation Kit for the MAX3987

Quality and Environmental Data

Product Reliability Reports: MAX3987.pdf 
Lead-Free Package Tin (Sn) Whisker Reports

Related Resources