TIDUF39 March   2025

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Key System Specifications
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
    3. 2.3 Highlighted Products
      1. 2.3.1 DAC70502: Dual-Channel, 1-LSB INL, 14-Bit, SPI Voltage-Output Digital-to-Analog Converter (DAC)
      2. 2.3.2 INA818: 35μV Offset, 8nV/√Hz Noise, Low-Power, Precision Instrumentation Amplifier
      3. 2.3.3 OPA192: High-Voltage, Rail-to-Rail Input/Output, 5µV, 0.2µV/°C, Precision Operational Amplifier
      4. 2.3.4 LM5146: 100V Synchronous Buck DC/DC Controller With Wide Duty Cycle Range
  9. 3System Design Theory
    1. 3.1 Constant Current Control Design
    2. 3.2 Constant Current and Voltage Simulation
  10. 4Hardware, Software, Testing Requirements, and Test Results
    1. 4.1 Hardware Requirements
    2. 4.2 Software Requirements
    3. 4.3 Test Setup
      1. 4.3.1 Constant Current Test Setup
      2. 4.3.2 Constant Voltage Test Setup
    4. 4.4 Test Results
      1. 4.4.1 Current Control Accuracy
      2. 4.4.2 Voltage Control Accuracy
      3. 4.4.3 CC, CV Transformation
      4. 4.4.4 Constant Current Transient Response
      5. 4.4.5 Constant Voltage Transient Response
      6. 4.4.6 Voltage Ripple at Short Circuit
      7. 4.4.7 Tracking DC-DC output
  11. 5Design and Documentation Support
    1. 5.1 Design Files
      1. 5.1.1 Schematics
      2. 5.1.2 BOM
    2. 5.2 Tools and Software
    3. 5.3 Documentation Support
    4. 5.4 Support Resources
    5. 5.5 Trademarks
  12. 6About the Author

4.4.1 Current Control Accuracy

TIDA-010089 CC Control Accuracy Figure 4-6 CC Control Accuracy

The current loop can be affected by the variation of the output voltage level. To assess any impact on the control loop, perform a load regulation test. Table 4-1 shows the CC load regulation for charging and Table 4-2 shows the CC load regulation for discharging.

Table 4-1 Constant Current Load Regulation for Charging
FULL SCALE
RATING (FSR) (A)		 8
ISET (A) 0.1 1 2 4 6 8
CV E-LOAD ISENSE (A)
1 0.09987 1.00033 2.00033 3.99933 6.00033 7.99933
2 0.09933 1.00033 2.00033 3.99933 6.00033 7.99933
4 0.09933 1.00033 2.00000 4.00033 6.00067 8.00133
8 0.09967 1.00067 2.00067 4.00067 6.00167 8.00500
10 0.09967 1.00003 2.00033 4.00067 6.00167 8.00567
14 0.09967 1.00067 2.00067 4.00033 6.00133 8.00667
ERROR (%FSR) 0.00833 –0.00833 –0.00833 –0.00833 –0.02083 –0.08333
Table 4-2 Constant Current Load Regulation for Discharging
FSR (A) –8
ISET (A) 0.1 1 2 3 4 5
CV POWER
SUPPLY (BATTERY)		 ISENSE (A)
1 –0.10133 –1.00133 –2.00167 –3.00167 –4.00167 NA
2 –0.10167 –1.00167 –2.00167 –3.00167 –4.00167 –5.00167
3 –0.10167 –1.00167 –2.00167 –3.00167 –4.00167 –5.00167
4 –0.10167 –1.00167 –2.00167 –3.00167 –4.00167 –5.00167
4.2 –0.10167 –1.00167 –2.00167 –3.00167 –4.00167 –5.00167
ERROR (%FSR) 0.02083 0.02083 0.02083 0.02083 0.02083 0.02083