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

3 Design 2: LM749x0-Q1 as Ideal Diode Controller with Current Monitoring, Overcurrent and Undervoltage Fault Indication

Figure 3-1 shows the LM749x0-Q1 configuration for ideal diode-only designs.

GUID-20230523-SS0I-WTQG-C4RH-0SWWPQNLWQ5D-low.svgFigure 3-1 Typical Application Circuit for Ideal Diode-Only Designs

In this configuration, the device will drive only ideal diode FET providing input reverse polarity protection and reverse current blocking functionality. As application diagram depicts powerpath disconnect functionality is not available. Device can monitor load current using integrated current sense amplifier and provide the load current information on IMON pin for system power budgeting. Certain system fault indication (no fault protection) are still present over device fault pins such as input undervoltage, load overcurrent, load short circuit events. For application where only fault indication is required, user can populate respective components to configure undervoltage (UVLO), overcurrent (ILIM), and short circuit (ISCP) thresholds.

LM749x0-Q1 when used to drive only ideal diode FET following pin configuration can be followed for unused pins

HGATE, TMR, SLEEPOV: needs to be left floating

ILIM, OV, OUT: needs to be connected to GND