SLYA042 July   2024 FDC1004 , FDC1004-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. Introduction
  5. CSAs and Input Bias Stage
  6. CSA and Gain Error Factor
  7. Applications for Resistance at Input Pins of Current Sense Amplifiers
    1. 4.1 Input Resistance Design Considerations
  8. Applications for Input Resistance at Reference Pins of Current Sense Amplifiers
    1. 5.1 Bidirectional CSA and Applications
    2. 5.2 Driving CSA Reference Pin With High-Resistance Source Voltage
    3. 5.3 Input Resistance at Reference Pin Design Considerations
  9. Design Procedure and Error Calculation for External Input Resistance on CSA
    1. 6.1 Calculating eEXT for INA185A4 With 110Ω Input Resistors
  10. Design Procedure for Input Resistance on Capacitively-Coupled Current Sense Amplifier
    1. 7.1 Bench Verification of Input eEXT for Capacitively-Coupled Current Sense Amplifiers
  11. Design Procedure for Input Resistance at CSA Reference Pins
  12. Input Resistance Error Test with INA185 Over Temperature
    1. 9.1 Schematic
    2. 9.2 Methods
    3. 9.3 Theoretical Model
    4. 9.4 Data for INA185A4 with 110Ω Input Resistors
      1. 9.4.1 Data Calculations
    5. 9.5 Analysis
  13. 10Input Resistance Error Test with INA191 Over Temperature
    1. 10.1 Schematic
    2. 10.2 Methods
    3. 10.3 Theoretical Model
    4. 10.4 Data for INA191A4 With 2.2kΩ Input Resistors
      1. 10.4.1 Data Analysis
    5. 10.5 Analysis
  14. 11Derivation of VOS, EXT for a Single Stage Current Sense Amplifier (CSA)
  15. 12Summary
  16. 13References

Data for INA185A4 with 110Ω Input Resistors

VCM = 12V

Table 9-5 Input-Output Sweep with INA185A4 and REXT = 0Ω
VDIFF (mV)VREF (V)VOUT, Differential (V)
-40°C25°C+125°C-40°C25°C+125°C
-0.50.181290.181140.18094-0.10265-0.102-0.10124
00.181290.181140.18094-0.00266-0.002-0.00131
120.181330.181180.189982.3972.3962.397
230.181360.181210.181014.5964.5954.596
23.50.181360.181210.181014.6964.6964.696
23.750.181360.181210.181014.7454.7454.7459
Table 9-6 VOUT versus VCM with INA185A4 and REXT = 0Ω at 125°C
VDIFF (mV)VCM (V)VREF (V)VOUT, Differential (V)
23150.189884.59534
2390.172134.59674
23250.219484.59294
2300.145554.59945

VCM = 12V

Table 9-7 Input-Output Sweep with INA185A4 and REXT = 110Ω
VDIFF (mV)VREF (V)VOUT, Differential (V)
-40°C25°C+125°C-40°C25°C+125°C
-0.80.181320.181150.18096-0.14397-0.1438-0.14342
-0.750.181320.181150.18097-0.13515-0.1349-0.13463
-0.60.181310.181150.18097-0.1087-0.1085-0.10818
-0.50.181320.181150.18097-0.09107-0.0909-0.09054
-0.250.181320.181150.18097-0.04695-0.0468-0.04649
00.181320.181150.18097-0.00287-0.003-0.00246
120.181350.181190.1812.113732.11382.112353
230.181380.181220.181044.053954.05394.05098
23.50.181380.181220.181044.1421444.14214.139073
23.750.181390.181220.181044.1862654.18624.183144
240.181380.181220.181044.230354.23034.2272
250.181390.181220.181044.4067364.40674.403448
260.181390.181230.181054.5831174.58314.579667
26.50.181390.181230.18054.6713084.67134.667844
270.181390.181230.181054.7595064.75954.755963
Table 9-8 VOUT versus VCM with INA185A4 and REXT = 110Ω at 125°C
VDIFF (mV)VCM (V)VREF (V)VOUT, Differential (V)
26.1120.181044.59735
26.1150.189914.5966
26.190.172174.59804
26.1250.219454.59397
26.100.145554.60547