Datasheet
Max_Current=Current_LSB 32767´
Max_Current=0.06226
(15)
Max_ShuntVoltage=Max_Current_Before_Overflow R´
SHUNT
Max_ShuntVoltage=0.3113
(16)
MaximumPower=Max_Current_Before_Overflow V´
BUS_MAX
MaximumPower=1.992
(17)
Corrected_Full_Scale_Cal=trunc
Cal MeasShuntCurrent
INA209_Current
´
Corrected_Full_Scale_Cal=3462
(18)
INA209
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......................................................................................................................................................... SBOS403B – JUNE 2007 – REVISED MARCH 2009
7. Compute the maximum current and shunt voltage values (before overflow), as shown by Equation 15 and
Equation 16 . Note that both Equation 15 and Equation 16 involve an If - then condition.
If Max_Current ≥ Max Possible_I then
Max_Current_Before_Overflow = MaxPossible_I
Else
Max_Current_Before_Overflow = Max_Current
End If
(Note that Max_Current is less than MaxPossible_I in this example.)
Max_Current_Before_Overflow = 0.06226 (Note: This result is displayed by software as seen in Figure 26 .)
If Max_ShuntVoltage ≥ V
SHUNT_MAX
Max_ShuntVoltage_Before_Overflow = V
SHUNT_MAX
Else
Max_ShuntVoltage_Before_Overflow= Max_ShuntVoltage
End If
(Note that Max_ShuntVoltage is less than V
SHUNT_MAX
in this example.)
Max_ShuntVoltage_Before_Overflow = 0.3113 (Note: This result is displayed by software as seen in
Figure 26 .)
8. Compute the maximum power with equation 8.
9. (Optional second calibration step.) Compute the corrected full-scale calibration value based on measured
current.
INA209_Current = 0.06226
MeaShuntCurrent = 0.05
Figure 26 illustrates how to perform the same procedure discussed in this example using the automated
INA209EVM software. Note that the same numbers used in the nine-step example are used in the software
example in Figure 26 . Also note that Figure 26 illustrates which results correspond to which step (for
example, the information entered in Step 1 is enclosed in a box in Figure 26 and labeled).
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