SWCS134A October   2017  – February 2025 TPS6508700

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  Electrical Characteristics: Total Current Consumption
    6. 5.6  Electrical Characteristics: Reference and Monitoring System
    7. 5.7  Electrical Characteristics: Buck Controllers
    8. 5.8  Electrical Characteristics: Synchronous Buck Converters
    9. 5.9  Electrical Characteristics: LDOs
    10. 5.10 Electrical Characteristics: Load Switches
    11. 5.11 Digital Signals: I2C Interface
    12. 5.12 Digital Input Signals (CTLx)
    13. 5.13 Digital Output Signals (IRQB, GPOx)
    14. 5.14 Timing Requirements
    15. 5.15 Switching Characteristics
    16. 5.16 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 SMPS Voltage Regulators
      1. 6.3.1 Controller Overview
      2. 6.3.2 Converter Overview
      3. 6.3.3 Dynamic Voltage Scaling
      4. 6.3.4 Current Limit
    4. 6.4 LDO Regulators and Load Switches
      1. 6.4.1 VTT LDO
      2. 6.4.2 LDOA1–LDOA3
      3. 6.4.3 Load Switches
    5. 6.5 Power Good Information (PGOOD or PG) and GPO Pins
    6. 6.6 Power Sequencing and Voltage-Rail Control
      1. 6.6.1 Power-Up and Power-Down Sequencing
      2. 6.6.2 Emergency Shutdown
    7. 6.7 Device Functional Modes
      1. 6.7.1 Off Mode
      2. 6.7.2 Standby Mode
      3. 6.7.3 Active Mode
    8. 6.8 I2C Interface
      1. 6.8.1 F/S-Mode Protocol
    9. 6.9 Register Maps
      1. 6.9.1  Register Map Summary
      2. 6.9.2  DEVICEID: PMIC Device and Revision ID Register (offset = 1h) [reset = 10h]
      3. 6.9.3  IRQ: PMIC Interrupt Register (offset = 2h) [reset = 0h]
      4. 6.9.4  IRQ_MASK: PMIC Interrupt Mask Register (offset = 3h) [reset = FFh]
      5. 6.9.5  PMICSTAT: PMIC Status Register (offset = 4h) [reset = 0h]
      6. 6.9.6  SHUTDNSRC: PMIC Shut-Down Event Register (offset = 5h) [reset = 0h]
      7. 6.9.7  BUCK2CTRL: BUCK2 Control Register (offset = 21h) [reset = 50h]
      8. 6.9.8  BUCK3DECAY: BUCK3 Decay Control Register (offset = 22h) [reset = 70h]
      9. 6.9.9  BUCK3VID: BUCK3 VID Register (offset = 23h) [reset = 70h]
      10. 6.9.10 BUCK3SLPCTRL: BUCK3 Sleep Control VID Register (offset = 24h) [reset = 70h]
      11. 6.9.11 BUCK4CTRL: BUCK4 Control Register (offset = 25h) [reset = Dh]
      12. 6.9.12 BUCK5CTRL: BUCK5 Control Register (offset = 26h) [reset = Dh]
      13. 6.9.13 BUCK6CTRL: BUCK6 Control Register (offset = 27h) [reset = Dh]
      14. 6.9.14 LDOA2CTRL: LDOA2 Control Register (offset = 28h) [reset = Ch]
      15. 6.9.15 LDOA3CTRL: LDOA3 Control Register (offset = 29h) [reset = 3Ch]
      16. 6.9.16 DISCHCTRL1: Discharge Control1 Register (offset = 40h) [reset = 55h]
      17. 6.9.17 DISCHCTRL2: Discharge Control2 Register (offset = 41h) [reset = 55h]
      18. 6.9.18 DISCHCTRL3: Discharge Control3 Register (offset = 42h) [reset = 15h]
      19. 6.9.19 PG_DELAY1: Power Good Delay1 Register (offset = 43h) [reset = 0h]
      20. 6.9.20 FORCESHUTDN: Force Emergency Shutdown Control Register (offset = 91h) [reset = 0h]
      21. 6.9.21 BUCK2SLPCTRL: BUCK2 Sleep Control Register (offset = 93h) [reset = 50h]
      22. 6.9.22 BUCK4VID: BUCK4 VID Register (offset = 94h) [reset = 20h]
      23. 6.9.23 BUCK4SLPVID: BUCK4 Sleep VID Register (offset = 95h) [reset = 20h]
      24. 6.9.24 BUCK5VID: BUCK5 VID Register (offset = 96h) [reset = 70h]
      25. 6.9.25 BUCK5SLPVID: BUCK5 Sleep VID Register (offset = 97h) [reset = E8h]
      26. 6.9.26 BUCK6VID: BUCK6 VID Register (offset = 98h) [reset = E8h]
      27. 6.9.27 BUCK6SLPVID: BUCK6 Sleep VID Register (offset = 99h) [reset = E8h]
      28. 6.9.28 LDOA2VID: LDOA2 VID Register (offset = 9Ah) [reset = FFh]
      29. 6.9.29 LDOA3VID: LDOA3 VID Register (offset = 9Bh) [reset = AAh]
      30. 6.9.30 BUCK123CTRL: BUCK1-3 Control Register (offset = 9Ch) [reset = 7h]
      31. 6.9.31 PG_DELAY2: Power Good Delay2 Register (offset = 9Dh) [reset = 21h]
      32. 6.9.32 SWVTT_DIS: SWVTT Disable Register (offset = 9Fh) [reset = E0h]
      33. 6.9.33 I2C_RAIL_EN1: VR Pin Enable Override1 Register (offset = A0h) [reset = 80h]
      34. 6.9.34 I2C_RAIL_EN2/GPOCTRL: VR Pin Enable Override2/GPO Control Register (offset = A1h) [reset = 89h]
      35. 6.9.35 PWR_FAULT_MASK1: VR Power Fault Mask1 Register (offset = A2h) [reset = C0h]
      36. 6.9.36 PWR_FAULT_MASK2: VR Power Fault Mask2 Register (offset = A3h) [reset = 3Fh]
      37. 6.9.37 GPO1PG_CTRL1: GPO1 PG Control1 Register (offset = A4h) [reset = C2h]
      38. 6.9.38 GPO1PG_CTRL2: GPO1 PG Control2 Register (offset = A5h) [reset = AFh]
      39. 6.9.39 GPO4PG_CTRL1: GPO4 PG Control1 Register (offset = A6h) [reset = 0h]
      40. 6.9.40 GPO4PG_CTRL2: GPO4 PG Control2 Register (offset = A7h) [reset = 0h]
      41. 6.9.41 GPO2PG_CTRL1: GPO2 PG Control1 Register (offset = A8h) [reset = C0h]
      42. 6.9.42 GPO2PG_CTRL2: GPO2 PG Control2 Register (offset = A9h) [reset = 2Fh]
      43. 6.9.43 GPO3PG_CTRL1: GPO3 PG Control1 Register (offset = AAh) [reset = 0h]
      44. 6.9.44 GPO3PG_CTRL2: GPO3 PG Control2 Register (offset = ABh) [reset = 0h]
      45. 6.9.45 MISCSYSPG Register (offset = ACh) [reset = FFh]
      46. 6.9.46 LDOA1CTRL: LDOA1 Control Register (offset = AEh) [reset = 7Dh]
      47. 6.9.47 PG_STATUS1: Power Good Status1 Register (offset = B0h) [reset = 0h]
      48. 6.9.48 PG_STATUS2: Power Good Status2 Register (offset = B1h) [reset = 0h]
      49. 6.9.49 PWR_FAULT_STATUS1: Power Fault Status1 Register (offset = B2h) [reset = 0h]
      50. 6.9.50 PWR_FAULT_STATUS2: Power Fault Status2 Register (offset = B3h) [reset = 0h]
      51. 6.9.51 TEMPCRIT: Temperature Fault Status Register (offset = B4h) [reset = 0h]
      52. 6.9.52 TEMPHOT: Temperature Hot Status Register (offset = B5h) [reset = 0h]
      53. 6.9.53 OC_STATUS: Overcurrent Fault Status Register (offset = B6h) [reset = 0h]
  8. 7 Applications, Implementation, and Layout
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Controller Design Procedure
          1. 7.2.2.1.1 Controller With External Feedback Resistor
          2. 7.2.2.1.2 Selecting the Inductor
          3. 7.2.2.1.3 Selecting the Output Capacitors
          4. 7.2.2.1.4 Selecting the FETs
          5. 7.2.2.1.5 Bootstrap Capacitor
          6. 7.2.2.1.6 Setting the Current Limit
          7. 7.2.2.1.7 Selecting the Input Capacitors
        2. 7.2.2.2 Converter Design Procedure
          1. 7.2.2.2.1 Selecting the Inductor
          2. 7.2.2.2.2 Selecting the Output Capacitors
          3. 7.2.2.2.3 Selecting the Input Capacitors
        3. 7.2.2.3 LDO Design Procedure
      3. 7.2.3 Application Curves
      4. 7.2.4 Layout
        1. 7.2.4.1 Layout Guidelines
        2. 7.2.4.2 Layout Example
    3. 7.3 Power Supply Coupling and Bulk Capacitors
    4. 7.4 Dos and Don'ts
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information
7.2.2.1.2 Selecting the Inductor

Placement of an inductor is required between the external FETs and the output capacitors. Together, the inductor and output capacitors make the double-pole that contributes to stability. Additionally, the inductor is directly responsible for the output ripple, efficiency, and transient performance. As the inductance used increases, the ripple current decreases, which typically results in increased efficiency. However, as the inductance used increases, the transient performance decreases. Finally, the inductor selected must be rated for appropriate saturation current, core losses, and DC resistance (DCR).

Use Equation 4 to calculate the recommended inductance for the controller.

Equation 4. TPS6508700

where

  • VOUT is the typical output voltage.
  • VIN is the typical input voltage.
  • fSW is the typical switching frequency.
  • IOUT(MAX) is the maximum load current.
  • KIND is the ratio of ILripple to the IOUT(MAX). For this application, TI recommends that KIND is set to a value from 0.2 to 0.4.

With the chosen inductance value, the peak current for the inductor in steady state operation, IL(MAX), can be calculated using Equation 5. The rated saturation current of the inductor must be higher than the IL(MAX) current.

Equation 5. TPS6508700