1 Features
• Four channel DisplayPort 2.1 linear redriver or
repeater with integrated 2:1 MUX
• Supports embedded (eDP) and DisplayPort 2.1 up
to 20Gbps - RBR, HBRx, UHBRx
• Supports DP++ (also called an AC-coupled HDMI)
up to 24Gbps
• Protocol agnostic, linear equalizer supporting AC
coupled interfaces up to 24Gbps
• Single 3.3V supply
• Low 720mW active power for 4-channel operation
• Excellent electrical performance at 20Gbps
(10GHz Nyquist):
– 19dB equalization
– 1.8V DC linearity, 1.08V AC linearity
– -15dB / -16dB Rx / Tx return loss
– -60dB NEXT, -43dB FEXT crosstalk
– 70fs low additive RJ with PRBS data
• Low latency of 90ps
• Transparent to DisplayPort 1.4 and 2.1 link training
• Device configuration by pin control or SMBus / I2C
– 18EQ boost settings, 5 flat gain settings
• -40°C to 85°C temperature range
• 3.5 × 9mm 42 Pin 0.5mm pitch WQFN package

2 Applications
• Desktop PC and motherboard
• PC, notebooks, tablets
• Docking stations
• TV, gaming, home theater, and entertainment
• Pro audio, video, and signage
• Test and measurement
• Medical
• Flat panel monitors

3 Description
The TDP20MB421 is a 4-channel linear redriver
with an integrated 2:1 MUX. The low-power, highperformance
linear redriver is designed to support
DisplayPort 2.1 up to 20Gbps.
The TDP20MB421 receivers deploy continuous time
linear equalizers (CTLE) to provide a programmable
high-frequency boost. The equalizer opens an input
eye that is completely closed due to inter-symbol
interference (ISI) induced by an interconnect medium,
such as PCB traces. A CTLE receiver is followed
by a linear output driver. The linear data paths
of TDP20MB421 preserve the characteristics of
the transmit preset. High bandwidth, low channel-tochannel
crosstalk, low additive jitter, and excellent
return loss make the device almost a passive element
in the link. The DisplayPort link training is effective
through the device as the device becomes part of the
passive channel between the source Tx and sink Rx.
The device transparency in the link-training protocol
results in the best electrical link and lowest possible
latency. The data path of the device uses an internally
regulated power rail that provides high immunity to
supply noise on the board.
The TDP20MB421 implements high-speed testing
during production for reliable, high-volume
manufacturing. The device also has low AC and DC
gain variation, providing consistent equalization in
high-volume platform deployment.