

13W3
13W3 Video Snake Oil
- Size
- 52 × 53.6 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 22
- Nets
- 30
- Pads
- 84
- Tracks, vias
- 108, 84
- Pours
- 2
- Routed
- Yes
- KiCad
- KiCad 6 (file 20211014)
- Created
- 16 Jul 2023
- Updated
- 3 Oct 2023
Overview
13W3 is an open-source printed circuit board by schlae, from the schlae/13W3 repository on GitHub. It is a 2-layer board of 52 × 53.6 mm with 22 parts on 30 nets, routed with 108 tracks and 84 vias.
It is built around the LMH1980MM. Its parts include 5 connectors, 3 capacitors, 2 resistors and 1 IC.
Main components
1README
README.md13W3 Video Snake Oil
Do you have an old workstation with a 13W3-style video connector? Are you frustrated with adapters that claim to convert this to a 15-pin analog VGA, but don't seem to work? Then this project is for you.

Board dimensions: 52mm x 53.6mm. 2-layers, standard board thickness. Fabricate it using whatever soldermask and silkscreen colors you prefer.
Assembly
Unless you need the composite sync separator, assembly is easy: just install J1 (a 13W3 connector, Mouser 636-685M13W3103L461 or equivalent) and J2 (a high-density 15-pin D shell connector, Mouser 636-181-015-213R561 or equivalent). Be warned that the 13W3 connector is quite expensive, so you may want to look at online auction sites or surplus sources.
You will need to solder some jumper wires to configure the 13W3 adapter for the particular workstation you are using. Ground pads are located next to the pads that are marked with the pin number that they are connected to. Using the table below, connect the pads to ground, leave them floating, or jumper them to the H (horizontal sync) or V (vertical sync) pads.
| 13W3 pin | Sun (old) | Sun (DDC) | RS/6000 [1] | SGI (old) [2] | SGI (DDC) [2] |
|---|---|---|---|---|---|
| 1 | n/c (serial read) | n/c (DDC SCL) | Gnd (ID-2) | n/c (id3) | n/c (DDC SCL) |
| 2 | n/c (Vsync) [3] | n/c (DDC 5V in) | n/c (ID-3) | n/c (id0) | n/c (DDC SDA) |
| 3 | n/c (sense2) [6] | n/c (sense2) [6] | Gnd (self test) | n/c (Csync) [5] | n/c (Csync) |
| 4 | Gnd (for sense) | Gnd (for DDC) | Gnd | n/c (Hdrive) [5] | H |
| 5 | H (Csync) [3] | H (Csync) [4] | H | n/c (Vdrive) [5] | V |
| 6 | n/c (Hsync) [3] | n/c (DDC SDA) | Gnd (ID-0) | n/c (id1) | n/c (DDC 5V in) |
| 7 | n/c (serial write) | n/c (Vsync) [4] | n/c (ID-1) | n/c (id2) | Gnd (for DDC) |
| 8 | n/c (sense1) [6] | n/c (sense1) [6] | n/c | Gnd | Gnd |
| 9 | n/c (sense0) [6] | n/c (sense0) [6] | V | Gnd | Gnd |
| 10 | Gnd (for sync) | Gnd (for sync) | Gnd | Gnd | Gnd |
Notes:
- The RS/6000 is wired for monitor ID 1010.
- The SGI wiring connections have not been tested but should work.
- Some video cards with Sun's old pinout lack Hsync and Vsync, so we connect Csync to the H pad, but see § Composite Sync for more details.
- All video cards with Sun's DDC pinout lack Hsync, so we connect Csync to the H pad, but see § Composite Sync for more details.
- Hdrive and Vdrive are not equivalent to Hsync and Vsync, so we connect Csync to the H pad, but see § Composite Sync for more details.
- Sense codes control the default resolution and refresh rate, unless DDC is supported and connected to your VGA monitor.
- default sense code 0002 is 1152x900@66
- jump pins 3 and 9 to Gnd (1012) for 1280x1024@76
- jump pin 8 to Gnd (0102) for 1024x768@60
- for other sense codes, see TurboGX/TurboGXplus Hardware Installation Guide, Table C-3
- not all sense codes are supported by all video cards, see the Sun Frame Buffer FAQ
Once you finish the wiring, it's a good idea to mark the board with the name of the system it is wired for. The space underneath the silkscreen text "FOR BEST RESULTS USE WITH:" is provided for this purpose.
If you figure out the wiring for a system not in this table, feel free to file a bug report or submit a pull request.
Composite Sync and Sync-On-Green
Some workstations output composite sync (Csync) or sync-on-green but not separate sync (Hsync and Vsync), such as the SPARCstation 5 with TurboGX.
Many modern LCD monitors already support one or both of these. In the case of sync-on-green, you may not need to wire up any sync signals at all, whereas for composite sync, it may be enough to connect your Csync pin to the H pad.
If yours doesn't support those, then you'll need to install these components:
| Q | Designator | Description | Mouser part number |
|---|---|---|---|
| 2 | C1, C3 | 0.1uF X5R 50V capacitor, 0603 | |
| 1 | C2 | 560pF C0G 50V capacitor, 0603 | |
| 1 | R1 | 100 ohm 5% 0603 resistor | |
| 1 | R2 | 10.0K ohm 1% 0603 resistor | |
| 1 | U1 | LMH1980 sync separator | 926-LMH1980MM/NOPB |
To separate sync-on-green, install a jumper wire across JP11. For composite sync, run a wire from the JP11 pad nearest R1 (marked CSYNC) to the appropriate pin on the 13W3 connector. Be sure to disconnect your Csync pin from the H pad, if you connected it earlier.
For this circuit to work, it needs 5V power, provided by J5 on the PCB (marked "5V GND"). If your workstation does not provide 5V on the 13W3 connector, you'll need to get it from somewhere else (keyboard port, external DC power supply, etc).
Parts
22| Qty | Value | Footprint | References |
|---|---|---|---|
| 11 | SolderJumper_2_Open | Passive:RESC2012X55 | JP1, JP2, JP3, JP4, JP5, JP6, JP7, JP8, JP9, JP10, JP11 |
| 2 | 0.1uF | Passive:CAPC2012X55 | C1, C3 |
| 1 | 100 | Passive:RESC2012X55 | R1 |
| 1 | 10K 1% | Passive:RESC2012X55 | R2 |
| 1 | 560pF | Passive:CAPC2012X55 | C2 |
| 1 | DB13W3 | Conn:DSUB-13W3 | J1 |
| 1 | H | TestPoint:TestPoint_Pad_1.0x1.0mm | J3 |
| 1 | LMH1980 | Active:SSOP50P500X110-10 | U1 |
| 1 | PWR | Connector_PinHeader_2.54mm:PinHeader_1x02_P2.54mm_Vertical | J5 |
| 1 | V | TestPoint:TestPoint_Pad_1.0x1.0mm | J4 |
| 1 | VGA | Conn:DB15HDFC | J2 |
Questions
How big is the 13W3 PCB?
It measures 52 × 53.6 mm and has 2 copper layers, 1.6 mm thick.
What parts does the 13W3 use?
22 parts, built around the LMH1980MM. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
Where can I download the 13W3 KiCad files?
From the schlae/13W3 repository on GitHub, at the commit this page was made from: the board is 13W3.kicad_pcb and its schematic 13W3.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the 13W3 design in my own project?
Its repository states no licence, so its author keeps all rights: ask schlae before reusing the design.
Similar boards
- 2 layers8.6 × 6.2 mm

- 2 layers58.4 × 55.9 mm

Analyzer pcb
caesarakalaeii/ir_racecar
This repository is for a lane detection system using infrared lights, multiple approaches will be explored
20 partsMIT - 4 layers100 × 77.5 mm

- 2 layers43.7 × 26.2 mm

RGBPlug P
Sirotaca/RGBPlug-P
Compact RGBS/RGBHV adapter for the PlayStation AV multi-out
20 partsCC0-1.0 - 2 layers100 × 50 mm

- 2 layers100.1 × 131.3 mm

BlankMSXCartHSH
cristianoag/trh9000
Open Source MSX Graphics Card based on the Yamaha V9990 chip
58 parts14CERN-OHL-S-2.0 - 2 layers158 × 11 mm

Daylight Matchstick
VoronDesign/Voron-Hardware
Cool Hardware designed by the Voron Design group
22 parts1.1kGPL-3.0 - 2 layers57 × 65 mm

Rgb to hdmi
hoglet67/RGBtoHDMI
Bare-metal Raspberry Pi project that provides pixel-perfect sampling of Retro Computer RGB/YUV video and conversion to HDMI
22 parts1kGPL-3.0