MC9328MX1 Datasheet, PDF (57/96 Pages) Freescale Semiconductor, Inc – i.MX Integrated Portable System Processor

3.11.3 Offset Calculations
The ideal mapping of input voltage to output digital sample is defined as:
Sample
Specifications
65535
G0
Smax
C0
-2400
Vi
1800
2400
Figure 36. Offset Calculations
In general, the mapping function is:
S=G*V+C
Where V is input, S is output, G is the slope, and C is the y-intercept.
Nominal Gain G₀ = 65535 / 4800 = 13.65mV^-1
Nominal Offset C₀ = 65535 / 2 = 32767
3.11.4 Gain Error Calculations
Gain error calculations are made using the information in this section.
Sample
65535
Smax
Gmax
G0
C0
- 2400
Vi
1800
2400
Figure 37. Gain Error Calculations
Assuming the offset remains unchanged, the mapping is rotated around y-intercept to determine the maximum gain
allowed. This occurs when the sample at 1800mV has just reached the ceiling of the 16-bit range, 65535.
MC9328MX1 Advance Information, Rev. 4
Freescale Semiconductor
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