SLVSGZ4A June   2023  – June 2024 TPS6521905

PRODUCTION DATA  

  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  System Control Thresholds
    6. 5.6  BUCK1 Converter
    7. 5.7  BUCK2, BUCK3 Converter
    8. 5.8  General Purpose LDOs (LDO1, LDO2)
    9. 5.9  General Purpose LDOs (LDO3, LDO4)
    10. 5.10 GPIOs and multi-function pins (EN/PB/VSENSE, nRSTOUT, nINT, GPO1, GPO2, GPIO, MODE/RESET, MODE/STBY, VSEL_SD/VSEL_DDR)
    11. 5.11 Voltage and Temperature Monitors
    12. 5.12 I2C Interface
    13. 5.13 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  Power-Up Sequencing
      2. 6.3.2  Power-Down Sequencing
      3. 6.3.3  Push Button and Enable Input (EN/PB/VSENSE)
      4. 6.3.4  Reset to SoC (nRSTOUT)
      5. 6.3.5  Buck Converters (Buck1, Buck2, and Buck3)
      6. 6.3.6  Linear Regulators (LDO1 through LDO4)
      7. 6.3.7  Interrupt Pin (nINT)
      8. 6.3.8  PWM/PFM and Low Power Modes (MODE/STBY)
      9. 6.3.9  PWM/PFM and Reset (MODE/RESET)
      10. 6.3.10 Voltage Select pin (VSEL_SD/VSEL_DDR)
      11. 6.3.11 General Purpose Inputs or Outputs (GPO1, GPO2, and GPIO)
      12. 6.3.12 I2C-Compatible Interface
        1. 6.3.12.1 Data Validity
        2. 6.3.12.2 Start and Stop Conditions
        3. 6.3.12.3 Transferring Data
    4. 6.4 Device Functional Modes
      1. 6.4.1 Modes of Operation
        1. 6.4.1.1 OFF State
        2. 6.4.1.2 INITIALIZE State
        3. 6.4.1.3 ACTIVE State
        4. 6.4.1.4 STBY State
        5. 6.4.1.5 Fault Handling
    5. 6.5 Multi-PMIC Operation
    6. 6.6 NVM Programming
      1. 6.6.1 TPS6521905 default NVM settings
      2. 6.6.2 NVM programming in Initialize State
      3. 6.6.3 NVM Programming in Active State
    7. 6.7 User Registers
    8. 6.8 Device Registers
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Typical Application Example
      2. 7.2.2 Design Requirements
      3. 7.2.3 Detailed Design Procedure
        1. 7.2.3.1 Buck1, Buck2, Buck3 Design Procedure
        2. 7.2.3.2 LDO1, LDO2 Design Procedure
        3. 7.2.3.3 LDO3, LDO4 Design Procedure
        4. 7.2.3.4 VSYS, VDD1P8
        5. 7.2.3.5 Digital Signals Design Procedure
      4. 7.2.4 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Receiving Notification of Documentation Updates
    2. 8.2 Support Resources
    3. 8.3 Trademarks
    4. 8.4 Electrostatic Discharge Caution
    5. 8.5 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

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

6.3.2 Power-Down Sequencing

An OFF-request or a shut-down-fault triggers the power-down sequence. The OFF-request can be triggered by a falling edge on EN/PB/VSENSE if configured for EN or VSENSE respectively a long press of the push-button if configured as PB or by an I2C-command to I2C_OFF_REQ in MFP_CTRL register. This bit self-clears.

An I2C-triggered shut-down requires a renewed ON-request on the EN/PB/VSENSE pin. In case of EN- or VSENSE-configuration, a low-going edge followed by a high-going-edge is required on the EN/PB/VSENSE-pin. The falling-edge deglitch time for EN or VSENSE configuration tDEGL_EN/VSENSE_I2C is shorter than the deglitch-time for pin-induced OFF-requests (tDEGL_EN_Fall and tDEGL_VSENSE_Fall). The deglitch-times for PB-configuration remain.

In many cases, the power-down sequence follows the reverse power-up sequence. In some applications, all rails can be required to shut down at the same time with no delay between rails or require wait-times to allow discharging of rail.

The power-down sequence is configured as follows:

  • The slot (respectively the position in the sequence) for each rail and GPO1, GPO2, GPIO, and nRSTOUT is defined using the corresponding *_SEQUENCE_SLOT registers, the four MSB for the ON-sequence, the four LSB for the down-sequencing.
  • The duration of each slot is defined in the POWER_DOWN_SLOT_DURATION_x registers and can be configured as 0 ms, 1.5 ms, 3 ms or 10 ms. In total, 16 slots can be configured, allowing the sequence to span over multiple TPS6521905-devices if more rails need to be supported.
  • In addition to the slot-duration, the power-down sequence is also gated by the previous rail being discharged below the SCG-threshold, unless active discharge is disabled on the previous rail. If that does not occur, the power-down of subsequent rails is paused. To allow for power-down in case of biased or shorted rails, the sequence continues despite an incomplete discharge of the previous rail after eight times the slot-duration (or 12 ms in case of slot-duration of 0 ms).
  • To bypass the discharge-check, set the bit BYPASS_RAILS_DISCHARGED_CHECK in register GENERAL_CONFIG to '1'.
Note: In case active discharge on a rail is disabled, unsuccessful discharge of the rail within the slot duration does not gate the disable of the subsequent rail, but the sequence is purely timing based. In case of residual voltage, the RV-bit is be set regardless.

Active discharge is enabled by default and not NVM based. Thus, if desired, discharge need to be disabled after each VSYS-power-cycle. During RESET or OFF-request, the discharge configuration is not reset, as long as VSYS is present. However, in INITIALIZE state and prior to the power-up-sequence, all rails get discharged, regardless of the setting.

During the power-down-sequence, non-EEPROM-backed bits get reset, with the exception of unmasked interrupt bits and *_DISCHARGE_EN bits.

Below graphic shows the power-down-sequence for NVM-ID 0x01, revision 0x2 as an example:

TPS6521905 Power-down sequencing (example) Figure 6-3 Power-down sequencing (example)
CAUTION: Do not change the registers related to an ongoing sequence by I2C-command!

Non-NVM-bits are not accessible for  approximately 80 μs after starting a transition into INITIALIZE state.