What was found
AIRCRAFT WAS GROUNDED: 0N CLIMB OUT THE PRESSURIZATION CLIMBED AT 2800 FT/MIN ON 3 EA'50DES WE LEVELED AT 19,000 DP WAS 3.9 CABIN ALT 7950 WE CHANGED PRESSURIZATION CONTROLLER WITH NO HELP. AIRCRAFT DIVERTED CLT WHERE IT LANDED SAFELY WITHOUT FURTHER INCIDENT. NOTE: NO EMERGENCY WAS DECLARED. MAINTENANCE PERFORMED A GROUND SCAN AND FOUND THE LOSS OF ANALOG OUTPUT OF THE CABIN PRESSURE CONTROLLER #1 TO THE #1 SYSTEM DATA ACQUISITION CONCENTRATOR (SDAC). REPLACED THE #1 SYSTEM DATA ACQUISITION CONCENTRATOR (SDAC). AND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK PER AMM 31-55-34.