Table 7-1. Total Error Calculation: Example 1 (1) (continued)

TERM

SYMBOL

EQUATION

MAX VALUE

Total input offset Current

IOS_Total

IOS_T2+ IOS_CM2+ IOS_REF2

40mA

Error from input offset

ErrorI

OS

IOS_Total

ISense ×100

0.16%

Gain error with Gain drift

ErrorG

GError+GError_drift×∆ T

0.35%

Error due to Gain

Nonlinearity

ErrorLin

GLin_Error×I2×100%

0.0937%

Total error

—

ErrorIOS2+ ErrorG+ErrorLin2

0.47%

(1)

The data for Total Error Example 1 is taken with the INA791x , VS = 5V, VCM = 48V, VREF = VS / 2, T = 25°C, External Unity Gain ( G =

20mV/A) and ISENSE = 25A.

7.1.1.5 Total Error Example 2

Table 7-2. Total Error Calculation: Example 2 (1)

TERM

SYMBOL

EQUATION

MAX VALUE

Input offset over Temp

IOS_T

IOS

70mA

Added input offset

because of common-mode

voltage

IOS_CM

CMRR× VCM–48V 

2.8mA

Added input offset

because of reference

voltage

IOS_REF

RVRR× VS2–VREF 

31.25mA

Total input offset Current

IOS_Total

IOS_T2+ IOS_CM2+ IOS_REF2

76.7mA

Error from input offset

ErrorI

OS

IOS_Total

ISense ×100

0.306%

Gain error with Gain drift

ErrorG

GError+GError_drift×∆ T

0.7%

Error due to Gain

Nonlinearity

ErrorLin

GLin_Error×I2×100%

0.0937%

Total error

—

ErrorIOS2+ ErrorG+ErrorLin2

0.85%

(1)

The data for Total Error Example 2 is taken with the INA791x , VS = 5V, VCM = 12V, VREF = 0V, T = 125°C, External Unity Gain ( G =

20mV/A) and ISENSE = 25A.

7.1.1.6 Total Error Example 3

Table 7-3. Total Error Calculation: Example 3 (1)

TERM

SYMBOL

EQUATION

MAX VALUE

Input offset over Temp

IOS_T

IOS

70mA

Added input offset

because of common-mode

voltage

IOS_CM

CMRR× VCM–48V 

2.8mA

Added input offset

because of reference

voltage

IOS_REF

RVRR× VS2–VREF 

31.25mA

Total input offset Current

IOS_Total

IOS_T2+ IOS_CM2+ IOS_REF2

76.71mA

Error from input offset

ErrorI

OS

IOS_Total

ISense ×100

0.307%

Gain error with Gain drift

ErrorG

GError+GError_drift×∆ T

0.7%

Error due to Gain

Nonlinearity

ErrorLin

GLin_Error×I2×100%

0.0937%

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SBOSAD1A – MAY 2024 – REVISED JULY 2025

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