18.5 CALIBRATION REGISTERS
BGCALCN: Background Calibration Control (Address 0x10)
Bit Bit Symbol Bit Description
[7:2] Reserved -
[1:0] BGCALN
Background calibration control – selects scheme for continuous background calibration.
0x0 (default): BgcalMode0: Background Calibration OFF
0x1: BgcalMode1: Offset Correction / Gain Estimation
0x2: BgcalMode2: Offset Correction / Gain Correction
0x3: BgcalMode3: Offset Estimation / Gain Estimation
SCALCN: System Calibration Control (Address 0x17)
Bit Bit Symbol Bit Description
[7:2] Reserved -
[1:0] SCALCN
System Calibration Control
When written, set SCALCN to:
0x0 (default): Normal Mode
0x1: “System Calibration Offset Coefficient Determination” mode
0x2: “System Calibration Gain Coefficient Determination” mode
0x3: Reserved
When read, this bit indicates the system calibration mode is in:
0x0: Normal Mode
0x1: "System Calibration Offset Coefficient Determination" mode
0x2: "System Calibration Gain Coefficient Determination" mode
0x3: Reserved
Note: when read, this bit will indicate the current System Calibration status. Since this co-
efficient determination mode will only take 1 conversion cycle, reading this register will only
return 0x00, unless this register is read within 1 conversion window.
CHx_SCAL_OFFSET: CH0-CH3 System Calibration Offset Registers (Two's-Complement)
ADDR
Name Description
CH0 CH1 CH2 CH3
0x30 0x38 0x40 0x48 CHx_SCAL_OFFSETH System Calibration Offset Coefficient Data [23:16]
0x31 0x39 0x41 0x49 CHx_SCAL_OFFSETM System Calibration Offset Coefficient Data [15:8]
0x32 0x3A 0x42 0x4A CHx_SCAL_OFFSETL System Calibration Offset Coefficient Data[7:0]
CHx_SCAL_GAIN: CH0-CH3 System Calibration Gain Registers (Fixed Point 1.23 Format)
ADDR
Name Description
CH0 CH1 CH2 CH3
0x33 0x3B 0x43 0x4B CHx_SCAL_GAINH System Calibration Gain Coefficient Data [23:16]
0x34 0x3C 0x44 0x4C CHx_SCAL_GAINM System Calibration Gain Coefficient Data [15:8]
0x35 0x3D 0x45 0x4D CHx_SCAL_GAINL System Calibration Gain Coefficient Data[7:0]
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