Matterhorn - KB8001

USB Type-C™ 40 Gb/s Multiprotocol Switch and Bidirectional Bit-Level Retimer

Part number Body size (nom)
KB8001 4.00 mm x 4.00 mm
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The KB8001 is a USB Type-C™ 40 Gb/s Multiprotocol Switch and Bidirectional Bit-Level Retimer that supports transmitter Feed-Forward Equalization and adaptive receiver equalization. This compensates for frequency-dependent cable and board trace loss up to 30 dB that can result in Inter-Symbol Interference. It requires adaptive RX equalization when the higher speed modes such as USB Super Speed, DP 1.4a, Thunderbolt 3, or other alternate modes need to travel across a PCB or cable.

All four lanes of the KB8001 are bidirectional. This makes it a versatile signal retimer applicable in both host (source) and device (sink) applications.

For host or device applications, the KB8001 enables the system to pass both transceiver compliance and receiver jitter tolerance tests for USB4 Gen 2,3, USB3.2 Gen 1,2 (Gen1x1, Gen1x2, Gen2x1, and Gen2x2), DP version 1.4a [(RBR 1.62 Gb/s, HBR3 8.1 Gb/s, HBR2 5.4 Gb/s, HBR 2.7 Gb/s and RBR 1.62 GBd) x1, x2, x4], Thunderbolt 2, 3 [(10.3125 Gb/s, 20.625 Gb/s) single lane operation, dual lane unbonded and dual-lane bonded operation].

A Two-Wire Interface (TWI) connects to the Power Delivery Microcontroller for initialization and configuration operations. The Sideband Use (SBU) interface carries sideband information used by the USB Type-C Alt Mode.

Block Diagram
Block diagram
Simplified Schematic
Simplified schematic

USB Type-C Alternate Mode interfaces, DisplayPort (DP), and Thunderbolt®.

Data rates up to 41.25 Gb/s.

Compatibility with C, D, E and F configurations defined by the Video Electronics Standards Association® DP Alternate Mode on the USB Type-C standard.

Configuration for custom USB Type-C alternate modes.


Mobile, tablet, and desktop PCs

Monitors, docking stations, and adapters

External hard disk and solid-state drives

Gaming consoles

Active cables


Reduces system costs via integrated SBU DC-blocking capacitors

Ultra-low active power with advanced power management monitoring

Compatible with legacy USB3.2, DP, and Thunderbolt modes

Rapid development time with on-chip diagnostics

Simple hardware integration

Compact package design for small form factor designs

Can be used for both source and sink applications


Multiprotocol reversible bit-level and separate reference clock with independent SSC retimer (BLR & SRIS) supporting up to 40 Gb/s:

  • USB Type-C with USB4 Gen2, Gen3 signaling for 20 and 40 Gb/s operation
  • USB Type-C with USB3.2 Super Speed+ signaling for 5 and 10 Gb/s operation (Gen1x1, Gen1x2, Gen2x1, and Gen2x2)
  • USB Type-C with DP1.4a (HBR3 8.1 Gb/s, HBR2 5.4 Gb/s, HBR 2.7 Gb/s, RBR 1.62 Gb/s) and x1, x2, x4
  • USB Type-C Alternate Mode with USB3.2 (Gen1x1 and Gen2x1) and DP 1.4 (HBR3 8.1 Gb/s, HBR2 5.4 Gb/s, HBR 2.7 Gb/s, RBR 1.62 Gb/s) x1, x2
  • USB Type-C Thunderbolt 3, 2 (20.625 Gb/s, and 10.3125 Gb/s) support single lane operation, dual lane unbonded and dual-lane bonded operation

Integrated mux to support combined USB3.2 and DP Type-C applications

Ultra-low power in active modes

Supports signal conditioning and retiming inside of Type-C active cables

Crossbar switch supporting a flexible datapath

Support for six cascaded retimers

TX de-emphasis for up to 8 dB at 10.315 GHz

RX advanced equalization with Decision Feedback Equalizer tap weight adjustment for equalization up to 30 dB at 10.315 GHz

Integrated loopback with line timing (retiming) functionality

On-chip diagnostics

Automatic offset calibration

Advanced power management by monitoring USB power states and snooping DP link training

Dynamic per-wire de-skew

PRBS7, PRBS15, PRBS31 pattern generation and verification

External configuration through TWI or SBU interfaces

Integrated SBU DC-blocking capacitors

Temperature range: 0ºC to 65ºC

4 mm × 4 mm 81p Flip-Chip Chip Scale Package (FCCSP) package

USB4™, USB Type-C® and USB-C® are trademarks of USB Implementers Forum. Thunderbolt™ is a trademark of Intel Corporation or its subsidiaries in the U.S. and/or other countries.