UDN6118/UDN7180 pinout and what each failure looks like
Both chips have inputs on pins 1-8, outputs on pins 11-18, ground on pin 9 and -100 V on pin 10 (pins 1 and 18 often unused on the 7180). A failed 7180 affects one display on later two-display games or two displays on older five-display games; a failed 6118 usually kills half a display. If a display is totally dark with plus and minus 100 V present, the glass is the likely fault.
Systems
Related tips
- Testing UDN6118/UDN7180 chips for shorts
- Check the segment resistors before buying a UDN7180
- One segment lit on many characters of the top display: unsoldered leg on a driver chip
- High-voltage fuse blows once the display connector is plugged back in
- System 9 versus System 11 display data
- Display board chips shown as 4050 are really 4049
- Same segment missing across one 16-digit display
- Characters missing from a display
Source: Repairing Williams System 11 Pinball 1986 to 1990, Part Three, Clay Harrell