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
8.2.1.2.9 Input and Output Protection

Proper operation of the LM5066Hx hot swap circuit requires a voltage clamping element present on the supply side of the connector into which the hot swap circuit is plugged in. A TVS is ideal, as depicted in Figure 8-9. The TVS is necessary to absorb the voltage transient generated whenever the hot swap circuit shuts off the load current. This effect is the most severe during a hot-short when a large current is suddenly interrupted when the FET shutts off. The TVS should be chosen to have minimal leakage current at VIN,MAX and to clamp the voltage to under 100V during hot-short events. For many high power applications 5.0SMDJ60A is a good choice.

If the load powered by the LM5066Hx hot swap circuit has inductive characteristics, a Schottky diode is required across the LM5066Hx’s output, along with some load capacitance. The capacitance and the diode are necessary to limit the negative excursion at the OUT pin when the load current is shut off.

LM5066H Output Diode Required for Inductive LoadsFigure 8-9 Output Diode Required for Inductive Loads