control register
| OPAMP4EN | OPAMP4 enable |
| FORCE_VP | FORCE_VP |
| VP_SEL | OPAMP4 Non inverting input selection |
| VM_SEL | OPAMP4 inverting input selection |
| TCM_EN | Timer controlled Mux mode enable |
| VMS_SEL | OPAMP4 inverting input secondary selection |
| VPS_SEL | OPAMP4 Non inverting input secondary selection |
| CALON | Calibration mode enable |
| CALSEL | Calibration selection |
| PGA_GAIN | Gain in PGA mode |
| USER_TRIM | User trimming enable |
| TRIMOFFSETP | Offset trimming value (PMOS) |
| TRIMOFFSETN | Offset trimming value (NMOS) |
| TSTREF | TSTREF |
| OUTCAL | OPAMP 4 ouput status flag |
| LOCK | OPAMP 4 lock |