VGA to SCART converter cable scheme

Wiring scheme for a VGA to SCART converter cable carrying analog RGB video and stereo audio between a PC graphics output and a European television.

15 pin highdensity D-SUB male connector layout 15 pin highdensity D-SUB male connector

21 pin SCART male connector diagram 21 pin SCART male connector

A VGA to SCART converter cable connects a PC graphics card’s 15-pin HD D-Sub (VGA) output to the 21-pin SCART socket found on European televisions and AV equipment. Both interfaces carry analog RGB video at 0.7 V peak-to-peak into 75 Ω, so no level conversion is required for the red, green, and blue channels. The critical difference is sync: VGA outputs separate horizontal and vertical TTL sync signals, whilst SCART RGB input (standardised under EN 50049-1 and IEC 60933-1:1988) expects composite sync. A passive wiring arrangement handles RGB and audio signal routing, but active sync-combining circuitry is required to merge the VGA H-sync and V-sync into a single composite sync signal for the SCART end. Additionally, SCART pin 16 (blanking/fast-blanking) must be driven to between 1 V and 3 V to command the television to switch into RGB mode.

Notes

  • VGA RGB signals (0.7 V peak-to-peak, 75 Ω) are directly compatible with SCART RGB inputs as defined in EN 50049-1.
  • VGA H-sync and V-sync are TTL-level separate signals; SCART RGB mode requires composite sync. An active sync combiner (e.g. XOR gate or dedicated IC) must merge these into a single composite sync signal.
  • SCART pin 16 (blanking): drive to 1–3 V to select RGB mode on the television; 0–0.4 V selects composite video mode.
  • SCART pin 8 carries aspect-ratio signalling: approximately 4.5–7 V indicates 16:9; 9.5–12 V indicates 4:3.
  • Audio signals may be routed passively from the PC’s audio output to SCART pins 2 (right audio input) and 6 (left audio input), with pin 4 as audio ground.
  • The SCART connector shell is defined mechanically by IEC 60807-9:1993 (two staggered rows of 10 contacts plus a shield contact, 21 signal contacts total).

References

Category:Audio Video Cables