SNVSCT1A October   2025  – December 2025 LM5066H

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Timing Requirements
    7. 6.7 PMBus Interface Timing Characteristics
    8. 6.8 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Current Limit
      2. 7.3.2  Foldback Current Limit
      3. 7.3.3  Soft Start Disconnect (SFT_STRT)
      4. 7.3.4  Circuit Breaker
      5. 7.3.5  Power Limit
      6. 7.3.6  UVLO
      7. 7.3.7  OVLO
      8. 7.3.8  Power Good
      9. 7.3.9  VDD Sub-Regulator
      10. 7.3.10 Remote Temperature Sensing
      11. 7.3.11 Damaged MOSFET Detection
      12. 7.3.12 Analog Current Monitor (IMON)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Power Up Sequence
      2. 7.4.2 Gate Control
      3. 7.4.3 Fault Timer and Restart
      4. 7.4.4 Shutdown Control
      5. 7.4.5 Enabling/Disabling and Resetting
    5. 7.5 Programming
      1. 7.5.1 PMBus Command Support
      2. 7.5.2 Detailed Descriptions of PMBus Commands
        1. 7.5.2.1  OPERATION (01h, Read/Write Byte)
        2. 7.5.2.2  CLEAR_FAULTS (03h, Send Byte)
        3. 7.5.2.3  WRITE_PROTECT (10h, Read/Write Byte)
        4. 7.5.2.4  RESTORE_FACTORY_DEFAULTS (12h, Send Byte)
        5. 7.5.2.5  STORE_USER_ALL (15h, Send Byte)
        6. 7.5.2.6  RESTORE_USER_ALL (16h, Send Byte)
        7. 7.5.2.7  CAPABILITY (19h, Read Byte)
        8. 7.5.2.8  VOUT_UV_WARN_LIMIT (43h, Read/Write Word)
        9. 7.5.2.9  OT_FAULT_LIMIT (4Fh, Read/Write Word)
        10. 7.5.2.10 OT_WARN_LIMIT (51h, Read/Write Word)
        11. 7.5.2.11 VIN_OV_WARN_LIMIT (57h, Read/Write Word)
        12. 7.5.2.12 IIN_OC_WARN_LIMIT (5Dh, Read/Write Word)
        13. 7.5.2.13 STATUS_BYTE (78h, Read Byte)
        14. 7.5.2.14 STATUS_WORD (79h, Read Word)
        15. 7.5.2.15 STATUS_VOUT (7Ah, Read Byte)
        16. 7.5.2.16 STATUS_INPUT (7Ch, Read Byte)
        17. 7.5.2.17 STATUS_TEMPERATURE (7Dh, Read Byte)
        18. 7.5.2.18 STATUS_CML (7Eh, Read Byte)
        19. 7.5.2.19 STATUS_OTHER (7Fh, Read Byte)
        20. 7.5.2.20 STATUS_MFR_SPECIFIC (80h)
        21. 7.5.2.21 READ_EIN (86h, Block Read)
        22. 7.5.2.22 READ_VIN (88h, Read Word)
        23. 7.5.2.23 READ_IIN (89h, Read Word)
        24. 7.5.2.24 READ_VOUT (8Bh, Read Word)
        25. 7.5.2.25 READ_IOUT (8Ch, Read Word)
        26. 7.5.2.26 READ_TEMPERATURE_1 (8Dh, Read Word)
        27. 7.5.2.27 READ_POUT (96h, Read Word)
        28. 7.5.2.28 READ_PIN (97h, Read Word)
        29. 7.5.2.29 PMBUS_REVISION (98h, Read Byte)
        30. 7.5.2.30 MFR_ID (99h, Block Read)
        31. 7.5.2.31 MFR_MODEL (9Ah, Block Read)
        32. 7.5.2.32 MFR_REVISION (9Bh, Block Read)
        33. 7.5.2.33 USER_DATA (BCh, Read/Write Byte)
        34. 7.5.2.34 READ_VIN_MIN (A0h, Read Word)
        35. 7.5.2.35 READ_VIN_PEAK (A1h, Read Word)
        36. 7.5.2.36 READ_IIN_PEAK (A2h, Read Word)
        37. 7.5.2.37 READ_PIN_PEAK (A3h)
        38. 7.5.2.38 READ_VOUT_MIN (A4h, Read Word)
        39. 7.5.2.39 READ_TEMP_AVG (C7h, Read Word)
        40. 7.5.2.40 READ_TEMP_PEAK (C8h, Read Word)
        41. 7.5.2.41 READ_SAMPLE_BUF (C9h, Block Read)
        42. 7.5.2.42 POWER_CYCLE (CAh, Send Byte)
        43. 7.5.2.43 READ_VAUX (D0h, Read Word)
        44. 7.5.2.44 MFR_READ_IIN (D1h, Read Word)
        45. 7.5.2.45 MFR_READ_PIN (D2h)
        46. 7.5.2.46 MFR_IIN_OC_WARN_LIMIT (D3h, F8h, Read/Write Word)
        47. 7.5.2.47 MFR_PIN_OP_WARN_LIMIT (D4h, Read/Write Word)
        48. 7.5.2.48 CLEAR_PIN_PEAK (D6h, Send Byte)
        49. 7.5.2.49 GATE_MASK (D7h, Read/Write Byte)
        50. 7.5.2.50 ALERT_MASK (D8h, Read/Write Word)
        51. 7.5.2.51 READ_VAUX_AVG (D9h, Read Word)
        52. 7.5.2.52 BLOCK_READ (DAh, Block Read)
        53. 7.5.2.53 SAMPLES_FOR_AVG (DBh, Read/Write Byte)
        54. 7.5.2.54 READ_VIN_AVG (DCh, Read Word)
        55. 7.5.2.55 READ_VOUT_AVG (DDh, Read Word)
        56. 7.5.2.56 READ_IIN_AVG (DEh, Read Word)
        57. 7.5.2.57 READ_PIN_AVG (DFh, Read Word)
        58. 7.5.2.58 CLEAR_BB_RAM (E0h, Send Byte)
        59. 7.5.2.59 READ_DIAGNOSTIC_WORD (E1h, Read Word)
        60. 7.5.2.60 AVG_BLOCK_READ (E2h, Block Read)
        61. 7.5.2.61 BB_ERASE (E3h, Send Byte)
        62. 7.5.2.62 BB_CONFIG (E4h, Read/Write Byte)
        63. 7.5.2.63 OC_BLANKING_TIMERS (E5h, Read/Write Byte)
        64. 7.5.2.64 DELAY_CONFIG (E7h, Read/Write Byte)
        65. 7.5.2.65 WD_PLB_ TIMER (E8h, Read/Write Byte)
        66. 7.5.2.66 PK_MIN_AVG (E9h, Read/Write Byte)
        67. 7.5.2.67 P2t TIMER (EAh, Read/Write Byte)
        68. 7.5.2.68 FETCH_BB_EEPROM (EBh, Send Byte)
        69. 7.5.2.69 READ_BB_RAM (ECh, Block Read)
        70. 7.5.2.70 ADC_CONFIG_1 (EDh, Read/Write Byte)
        71. 7.5.2.71 ADC_CONFIG_2 (EEh, Read/Write Byte)
        72. 7.5.2.72 DEVICE_SETUP1 (CCh, Read/Write Byte)
        73. 7.5.2.73 DEVICE_SETUP2 (EFh, Read/Write Byte)
        74. 7.5.2.74 DEVICE_SETUP3 (F0h, Read/Write Byte)
        75. 7.5.2.75 DEVICE_SETUP4 (CDh, Read/Write Byte)
        76. 7.5.2.76 DEVICE_SETUP5 (CEh, Read/Write Byte)
        77. 7.5.2.77 IIN OFFSET CALIBRATION (F2h, Read/Write Byte)
        78. 7.5.2.78 STATUS_MFR_SPECIFIC_2 (F3h, Read Word)
        79. 7.5.2.79 READ_BB_EEPROM (F4h, Block Read)
        80. 7.5.2.80 BB_TIMER (F6h, Read Byte)
        81. 7.5.2.81 PMBUS_ADDR (F7h, Read/Write Byte)
      3. 7.5.3 Reading and Writing Telemetry Data and Warning Thresholds
      4. 7.5.4 Determining Telemetry Coefficients Empirically With Linear Fit
      5. 7.5.5 Writing Telemetry Data
      6. 7.5.6 PMBus Address Lines (ADR0, ADR1, ADR2)
      7. 7.5.7 SMBA Response
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 54V, 100A PMBus Hot Swap Design
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design-In Procedure
          1. 8.2.1.2.1 Selecting the Hotswap FETs
          2. 8.2.1.2.2 dv/dt based Start-Up
            1. 8.2.1.2.2.1 Choosing the VOUT Slew Rate
          3. 8.2.1.2.3 Select RSNS and CL Setting
          4. 8.2.1.2.4 Select Power Limit
          5. 8.2.1.2.5 Set Fault Timer
          6. 8.2.1.2.6 Check MOSFET SOA
          7. 8.2.1.2.7 Set UVLO and OVLO Thresholds
            1. 8.2.1.2.7.1 Option A
            2. 8.2.1.2.7.2 Option B
            3. 8.2.1.2.7.3 Option C
            4. 8.2.1.2.7.4 Option D
          8. 8.2.1.2.8 Power Good Pin
          9. 8.2.1.2.9 Input and Output Protection
        3. 8.2.1.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Third-Party Products Disclaimer
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

7.3.7 OVLO

When VIN causes the OVLO pin voltage to exceed its threshold, the MOSFETs are turned off through a strong pulldown current (10mA or 1.5A) at the GATE pin, disconnecting load from the power supply. During an OVLO condition, an internal 21 μA current source activates at the OVLO pin, increasing the voltage to create threshold hysteresis for stable operation.

When VIN drops below the OVLO threshold, GATE1 reactivates first, followed by GATE2 turn on, but only after GATE1's gate-source voltage exceeds 8V and the drain-source voltage falls below 2V. An OVLO event sets multiple status flags: the VIN_OV_FAULT bit in the STATUS_INPUT (7Ch) register, the INPUT bit in the STATUS_WORD (79h) register, and the VIN_OVERVOLTAGE_FAULT bit in the DIAGNOSTIC_WORD (E1h) register. The SMBA pin pulls low during this condition unless disabled through the ALERT_MASK (D8h) register.

The Application and Implementation section provides procedures for calculating the appropriate threshold setting resistor values.