SBOA603 June   2024 INA700 , INA740A , INA740B , INA745A , INA745B , INA780A , INA780B

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Design Size
  6. 3Performance and Functionality
    1. 3.1 Total Error Comparison for Current ≤ 15A Over Temperature
    2. 3.2 Total Error Comparison for Current ≤ 25A Over Temperature
      1. 3.2.1 Common Mode Voltage ≤ 40V
      2. 3.2.2 Common Mode Voltage ≤ 80V
    3. 3.3 Total Error Comparison for Current ≤ 50A Over Temperature
  7. 4Summary
  8. 5References

Total Error Comparison for Current ≤ 15A Over Temperature

For this data set, the EZShunt™ device selected is the INA700, which is characterized for 15A at 25°C, along with the INA234 and three separate resistor sets shown in Table 3-1

Table 3-1 Resistors A, B, and C (≤ 15A)
Data SheetMeasured
ResistorResistance (mΩ)ToleranceDrift (ppm)ToleranceDrift (ppm)WattageCase Size1K price
A21%500.66%17.60.5W0805$0.081
B21%1500.44%56.70.5W1206$0.18
C21%2751.76%54.50.5W0603$0.63

The Benchmark data with our EZShunt™ against Discrete implementations with consecutive resistor sets are shown in Figure 3-1.

 INA700 vs INA234 and Resistor AFigure 3-1 INA700 vs INA234 and Resistor A
 INA700 vs INA234 and Resistor BFigure 3-2 INA700 vs INA234 and Resistor B
 INA700 vs INA234 + Resistor CFigure 3-3 INA700 vs INA234 + Resistor C

When comparing the total error for each design from 0A to 15A at 25°C and 125°C ambient field temperatures, we can determine the overall accuracy of the discrete design used in conjunction with either Resistor A, B, or C is far less in comparison to the INA700 at both temperature (25°C and 125°C) points throughout the data set regardless of current nor temperature. Thus, helps us infer, regardless of resistor type, or cost for use cases measuring below 15A, INA700 can offer the most accurate design for similar cost in the market.