SLVSHO1 March   2025 TPS1689

ADVANCE INFORMATION  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1  Absolute Maximum Ratings
    2. 5.2  ESD Ratings
    3. 5.3  Recommended Operating Conditions
    4. 5.4  Thermal Information
    5. 5.5  Electrical Characteristics
    6. 5.6  PMBus and GPIO DC Characteristics
    7. 5.7  Telemetry
    8. 5.8  Logic Interface
    9. 5.9  Timing Requirements
    10. 5.10 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1  Undervoltage Protection
      2. 6.3.2  Insertion Delay
      3. 6.3.3  Overvoltage Protection
      4. 6.3.4  Inrush Current, Overcurrent, and Short-Circuit Protection
        1. 6.3.4.1 Slew rate (dVdt) and Inrush Current Control
          1. 6.3.4.1.1 Start-Up Timeout
        2. 6.3.4.2 Steady-State Overcurrent Protection (Circuit-Breaker)
        3. 6.3.4.3 Active Current Limiting During Start-Up
        4. 6.3.4.4 Short-Circuit Protection
      5. 6.3.5  Analog Load Current Monitor (IMON)
      6. 6.3.6  Overtemperature Protection
      7. 6.3.7  Analog Junction Temperature Monitor (TEMP)
      8. 6.3.8  FET Health Monitoring
      9. 6.3.9  Single Point Failure Mitigation
        1. 6.3.9.1 IMON Pin Single Point Failure
        2. 6.3.9.2 IREF Pin Single Point Failure
      10. 6.3.10 General Purpose Digital Input/Output Pins
        1. 6.3.10.1 Fault Response and Indication (FLT)
        2. 6.3.10.2 Power Good Indication (PG)
        3. 6.3.10.3 Parallel Device Synchronization (SWEN)
      11. 6.3.11 Stacking Multiple eFuses for Unlimited Scalability
        1. 6.3.11.1 Current Balancing During Start-Up
      12. 6.3.12 Quick Output Discharge(QOD)
      13. 6.3.13 Write Protect Feature(WP#)
      14. 6.3.14 PMBus® Digital Interface
        1. 6.3.14.1  PMBus® Device Addressing
        2. 6.3.14.2  SMBus Protocol
        3. 6.3.14.3  SMBus™ Message Formats
        4. 6.3.14.4  Packet Error Checking
        5. 6.3.14.5  Group Commands
        6. 6.3.14.6  SMBus™ Alert Response Address (ARA)
        7. 6.3.14.7  PMBus® Commands
        8. 6.3.14.8  Analog-to-digital Converter
        9. 6.3.14.9  Digital-to-analog Converters
        10. 6.3.14.10 DIRECT format Conversion
        11. 6.3.14.11 Blackbox Fault Recording
    4. 6.4 Device Functional Modes
  8. 7 Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 Single Device, Standalone Operation
      2. 7.1.2 Single TPS1689 and multiple TPS1685 Devices, Parallel Connection
      3. 7.1.3 Multiple TPS1689 Devices: Parallel Connection With Individual Telemetry
      4. 7.1.4 Multiple Devices, Independent Operation (Multi-zone)
    2. 7.2 Typical Application: 54-V, 2-kW Power Path Protection with PMBus® Interface in Datacenter Servers
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
      3. 7.2.3 Application Performance Plots
    3. 7.3 Power Supply Recommendations
      1. 7.3.1 Transient Protection
      2. 7.3.2 Output Short-Circuit Measurements
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. 8 Application Limitation and Errata
  10. 9 Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    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
    1. 11.1 Mechanical Data

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

6.3.14.11 Blackbox Fault Recording

The Blackbox feature greatly enhances the ability of the system designer to debug power path related issues during design/development and in case of field returns. Along with a snapshot of the parametric data and event information through various status registers, the TPS1689 provides additional information which helps to re-create the sequence of events as they occurred in a certain interval of time. This information is available in both the on-chip volatile memory and the external I2C EEPROM (connected on the EECLK/EEDATA pins) and can be accessed through PMBus®.

Note:

The PMBus® engine is up and running as soon as a stable supply is available on VDD, independent of VIN and other related internal nodes. This ensures that the Blackbox contents can be read back from a field return unit by applying power on VDD pin even if there’s damage on VIN side or Power FET .

During the operation of the device, the Blackbox information is stored inside the Blackbox buffer RAM which is seven (7) bytes deep. At any point of time, issuing the READ_BB_RAM command will retrieve the most recent seven (7) events in a sequence along with the timestamp relative to each other. Each byte of this buffer RAM holds the following information about a single event:

  1. A 3-bit event identifier

  2. A 5-bit value which indicates the time lapse because the previous event. The lower 4 bits of the timer value represents a snapshot of the free running Blackbox tick timer at the instant of registering the event in the Blackbox RAM. The 5th bit indicates whether the timer has overflowed at least once since the last event.

The event identifier and relative timer information help the system designer to reconstruct a timeline of events as they occurred, thereby enhancing the debug capabilities as compared to viewing a single snapshot of status registers. The Blackbox tick timer is a free running timer which is reset to zero after every event. The timer update rate can be configured through the BB_CONFIG register. This allows the users to make a tradeoff between fine timing resolution and longer time span as per their debug needs. The BB_TMR_EXP bit in the BB_TIMER register indicates if the Blackbox tick timer has overflowed at least since the last event. This bit indicates whether the event entries in the RAM are relatively recent or old. This bit is latched when the timer overflows and reset to zero along with the free running timer when the next event occurs.

Here are the events which will trigger a write to the Blackbox RAM:

  1. VIN_UV_WARN

  2. VIN_OV_WARN

  3. OC_WARN

  4. OT_WARN

  5. OC_DET

  6. IN_OP_WARN

Once the device encounters a global fault or alert event (based on the ALERT_MASK), the Blackbox RAM contents, along with the status registers, peak input voltage, peak input current, peak device temperature, and Blackbox timer values are written to an external EEPROM through the EECLK/EEDATA pins.

Note:

The EEPROM interface is a standard I2C controller and operates at 400 kHz clock speed. TI recommends using an I2C EEPROM with minimum 1 Kbits of capacity and 16-byte page addressing. Examples of compatible EEPROM devices include 24LC04, 24AA04, etc.

The contents of the Blackbox RAM along with some status registers (STATUS_WORD, STATUS_MFR_SPECIFIC, and STATUS_INPUT) and certain parameters (VIN_PEAK, IIN_PEAK, and TEMPERATURE_PEAK) are stored into Page-0 of an external EEPROM when the following conditions are met. At the same time, Blackbox RAM contents and Blackbox tick timer values are locked.

  1. An external EEPROM is successfully connected by setting the EXT_EEPROM bit high in the DEVICE_CONFIG register. Make sure those two (2) selected GPIO pins are physically connected to the EEPROM clock and data pins respectively on the board.

  2. Any one of the three BB EEPROM write trigger bits is set in the BB_CONFIG register.

Blackbox EEPROM contents:

  1. BB_RAM_0 to BB_RAM_6 [Seven (7) bytes]

  2. BB_TIMER [One (1) byte]

  3. STATUS_WORD [Two (2) bytes]

  4. STATUS_MFR_SPECIFIC [One (1) byte]

  5. STATUS_INPUT [One (1) byte]

  6. VIN_PEAK [One (1) byte, Eight (8) MSBs from the 10-bit ADC output data]

  7. IIN_PEAK [One (1) byte, Eight (8) MSBs from the 10-bit ADC output data]

  8. TEMPERATURE_PEAK [One (1) byte, Eight (8) MSBs from the 10-bit ADC output data]

  9. CHECKSUM [One (1) byte]

TPS1689 Blackbox Operation Example Figure 6-16 Blackbox Operation Example