17.8.16 Voltage References System (VREF) Control
| Name: | VREF | 
| Offset: | 0x40 | 
| Reset: | 0x0XXX0000 | 
| Property: | Write-Protected | 
| Bit | 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | |
| CALIB[10:8] | |||||||||
| Access | R/W | R/W | R/W | ||||||
| Reset | x | x | x | ||||||
| Bit | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | |
| CALIB[7:0] | |||||||||
| Access | R/W | R/W | R/W | R/W | R/W | R/W | R/W | R/W | |
| Reset | x | x | x | x | x | x | x | x | |
| Bit | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | |
| Access | |||||||||
| Reset | 
| Bit | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
| BGOUTEN | TSEN | ||||||||
| Access | R/W | R/W | |||||||
| Reset | 0 | 0 | 
Bits 26:16 – CALIB[10:0] Bandgap Voltage Generator Calibration
These bits are used to calibrate the output level of the bandgap voltage reference. These bits are loaded from Flash Calibration Row at start-up.
Bit 2 – BGOUTEN Bandgap Output Enable
| Value | Description | 
|---|---|
| 0 | The bandgap output is not available as an ADC input channel | 
| 1 | The bandgap output is routed to an ADC input channel | 
Bit 1 – TSEN Temperature Sensor Enable(1)
| Value | Description | 
|---|---|
| 0 | Temperature sensor is disabled | 
| 1 | Temperature sensor is enabled and
                  routed to an ADC input channel Note: 1. The TSEN bit is not available on the DA1
                     device.  | 
            
