78M6610+LMU Data Sheet
Gain Correction
The system (sensors) and the 78M6610+LMU device inherently have gain errors that can be corrected by
using the gain registers. These registers can be directly accessed and modified by an external processor
or automatically updated by an integrated self calibration routine.
Input gain registers are signed fixed point numbers with the binary point to the left of bit 21. They are set
to 1.0 by default and have a usable range of 0 to 4 - LSB, negative values are not supported. The gain
equation for each input slot can be described as Sx = Sx * Sx_GAIN.
Register
S0_GAIN
S1_GAIN
S2_GAIN
S3_GAIN
Description
Voltage Input S0 Gain Calibration.
Current Input S1 Gain Calibration
Voltage Input S2 Gain Calibration.
Current Input S3 Gain Calibration
Die Temperature Compensation
The 78M6610+LMU has an on-chip temperature sensor that can be used by the signal processor for
monitoring the voltage reference error and made available to the user in the TEMPC register.
Setting the Temperature Compensation (TC) bit in the Command Register allows the firmware to further
adjust the system gain based on measured die temperature. Die Temperature Offset is typically
calibrated by the user during the calibration stage. Die temperature gain is set to a factory default value
for most applications, but can be adjusted by the user.
Register
T_OFFS
T_GAIN
Description
Die Temperature Offset Calibration.
Die Temperature Slope Calibration. Set by factory.
Voltage Reference Gain Adjustment
The on-chip precision bandgap voltage reference incorporates auto-zero techniques as well as production
trims to minimize errors caused by component mismatch and drift. It can be assumed that the part is
trimmed at 22°C to produce a uniform voltage reference gain at that temperature. The voltage reference
is digitally compensated over changes in measured die temperature using a quadratic equation.
18
Rev 0
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
