VGAX49

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VGAX49 P901-cropped-720px.jpg

Features

  • Digital VGA adapter
  • 16-bit digital video
    • 5:6:5 (R:G:B) mapping (maximum)
    • 2:2:2 (R:G:B) mapping (option)
  • Uses summing resistors
  • DB-15F connector
  • 49x49mm ODAS form factor
  • Mounting holes

Connectors

VGAX49.PNG

J1 - Digital Connections

P1 - VGA connector

Simulation

2:2:2 Resistor Simulation

  • 3.3V Drive out of FPGA
  • 1V is drive level for VGA specification
  • 8 mA max drive current
  • VGA presents a 75 Ohm load
  • Series resistors present a voltage divider between the resistors on the card and the VGA load
  • 1V at 75 Ohms is 13.3 mA
  • Each color is independently driven
  • The resistor with the smaller value has larger current from the FPGA pin

5:6:5 Resistor Simulation

  • 3.3V Drive out of FPGA
  • 1V is drive level for VGA specification
  • 8 mA max drive current
  • VGA presents a 75 Ohm load
  • Series resistors present a voltage divider between the resistors on the card and the VGA load
  • 1V at 75 Ohms is 13.3 mA
  • Each color is independently driven

Schematic

Assembly Sheet