PS8339 – 1:2 DP v1.2 to DP/TMDS Demux

Dual-Mode DisplayPort Source Demultiplexer with DisplayPort and TMDS Outputs, DP v1.2 and HDMI 1.4 capable

The PS8339 is a 1:2 demultiplexer IC that is connected to the output of a Dual-mode DisplayPort Source device.  It outputs either a repeated Dual-mode DisplayPort signal from its DisplayPort output, or an HDMI or DVI signal from it’s TMDS output.

Supports the higher data rates of DisplayPort 1.2:

  • Link Rates of 5.4Gb/s (HBR2), 2.7Gb/s (HBR), and 1.62Gb/s (RBR)
  • AUX Channel rate of 720 Mb/s (Fast AUX) and 1 Mb/s (Standard AUX)

Supports up to 300MHz TMDS clock rate for the TMDS DVI/HDMI output

  • Supports DVI, and HDMI 1.4b (1080P 3D @60Hz, or 4Kx2K @24 or 30Hz)
  • TMDS data rate of up to 3.0Gb/s (with TMDS clock rate of up to 300MHz)
  • Includes the Type 2 Dual-mode DisplayPort cable adaptor register to simply Source device driver support

When passing the Dual-mode DisplayPort signal from the device’s input to the DisplayPort output, the PS8339 behaves as a DisplayPort repeater/redriver device.  When the Source device is in TMDS mode, the AC coupled TMDS signal is converted to a DVI or HDMI compliant signal out the output through the use of an internal level-shifter.  The buffered DDC path through the device is connected to an internal I2C register that is configured as a Type 2 Dual-mode DisplayPort cable adaptor register, as per the VESA DisplayPort Dual-Mode Standard.  This allows the Dual-mode Source device driver to recognize the 300MHz capability of the level shifter function.

The Dual-mode DisplayPort output will also support an external level shifter-based DisplayPort-to-HDMI/DVI Dual-mode video adaptor (dongle). The PS8339 can be configured to use the output hot-plug detect pins to enable automatic mode switching and device power management.  An automatic output squelch function disables the outputs when no input signal is present.

The PS8339 can be used on the same circuit assembly as the Dual-mode DisplayPort Source device, or remotely such as in a notebook docking station.  To ensure the maintenance of optimal signal integrity, the device includes an automatic equalizer on the input to compensate for PC board, connector and cable losses.  When using the DisplayPort output, the PS8339 repeater / redriver function uses AUX channel interception, or “AUX snooping”, that enables it to respond to cable drive requirements indicated by the sink device during link training. This helps to ensure DisplayPort PHY compliance at the system output receptacle as well as to ensure robust interoperability with the display device, regardless of display cable length.

APPLICATIONS

  • PC Desktop and Notebook Motherboards
  • Notebook Docking Stations
  • Graphics Cards

KEY FEATURES

  • Supports Dual-mode DisplayPort™ (DP) De-multiplexing to a Dual-mode DisplayPort output and a TMDS™ output
  • Full HDMI or DVI interface support from the TMDS output
  • Compliant to the VESA DisplayPort 1.2 Standard — supports up to 5.4Gb/s link rate (HBR2), and AUX or Fast AUX
  • Compliant to the HDMI 1.4b specification — supports up to 3.0Gb/s TMDS output
  • Includes Type 2 Dual-mode adaptor register for Source driver discovery
  • Built-in AUX CH and DDC combiner for Dual-Mode Source support
  • DisplayPort repeater / redriver function included for the DisplayPort output, full link training for 1, 2 or 4 lanes (all 4 output amplitude levels and 4 pre-emphasis levels)
  • Supports transmitter Feed Forward Equalizer (FFE) with Post Cursor 2 on HBR2
  • Dual-mode DisplayPort operation supported by DisplayPort output
  • Automatic receiver equalization compensates for signal loss between Source device and PS8339
  • Automatic power management and output selection settings
  • Low power consumption
  • Source initiated power saving management
  • Device configuration can be through pin settings or I2C slave input, which offers additional device options
  • ESD performance 8kV Human Body Model (HBM)
  • 7x7mm 56-pin QFN package
  • 0 to 85°C operation

DEVICE OPTIONS — Dual Supply or Single Supply

  • PS8339A — Dual supplies, 1.5V & 3.3V
  • PS8339B — Single 3.3V Supply