SNOAA94 june   2023 LM74900-Q1 , LM74910-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1 LM749x0-Q1 Ideal Diode Controller Overview
  5. 2 Design 1: Automotive Reverse Battery Protection with Overvoltage, Undervoltage and Overcurrent Protection with Fault Output
  6. 3 Design 2: LM749x0-Q1 as Ideal Diode Controller with Current Monitoring, Overcurrent and Undervoltage Fault Indication
  7. 4 Design 3: LM749x0-Q1 as High Side Driver with Undervoltage, Overvoltage and Overcurrent Protection
  8. 5 Feature Comparison: LM749x0-Q1 as Ideal Diode FET and High Side Driver Topology
  9. 6 Design 4: Dual Supply OR-ing with Common Powerpath Disconnect Function
  10. 7 Design 5: LM749x0-Q1 as Priority Power MUX Controller
  11. 8 Feature Comparison: Dual OR-ing and Priority Power MUX Controller Topologies
  12. 9 Summary
  13. 10References

6 Design 4: Dual Supply OR-ing with Common Powerpath Disconnect Function

System designs with redundancy are common architecture in safety-critical designs such as ADAS systems. In these designs, the ECU input power can be from more than one supply connection.

Figure 6-1 shows the application circuit for a dual-supply input ORing with load disconnect control using the LM749x0-Q1 and LM74700-Q1 devices.

GUID-20230523-SS0I-DGZ5-ZCRP-RJBMBR2SZRWK-low.svgFigure 6-1 Typical Application Circuit for Supply ORing With Load Disconnect Control Designs

Based on the system redundancy architecture VBATT_1 and VBATT_2 can either be powered from two separate battery sources or can be connected to a common battery source through separate cables running through the fuse box. The downstream supply comes from ORed inputs and the various system fault protection features and disconnect switch operation is similar to as described in Section 2.