SLVSC20E January   2015  – October 2016 TPS62134A , TPS62134B , TPS62134C , TPS62134D

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommend Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Enable and Shutdown (EN)
      2. 8.3.2 Undervoltage Lockout (UVLO)
      3. 8.3.3 Soft-Start (SS) Circuitry
      4. 8.3.4 Switch Current-Limit and Short Circuit Protection
      5. 8.3.5 Output Voltage and LPM Logic Selection (VIDx and LPM)
      6. 8.3.6 Power-Good Output (PG)
      7. 8.3.7 Single-Ended Remote Sense (FBS)
      8. 8.3.8 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 PWM Operation and Power Save Mode
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Output Filter Selection
        2. 9.2.2.2 Inductor Selection
        3. 9.2.2.3 Output Capacitor
        4. 9.2.2.4 Input Capacitor
        5. 9.2.2.5 Soft-Start Capacitor
        6. 9.2.2.6 Program Output Voltage with External Resistor Divider
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
    3. 11.3 Thermal Considerations
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Related Links
    4. 12.4 Receiving Notification of Documentation Updates
    5. 12.5 Community Resources
    6. 12.6 Trademarks
    7. 12.7 Electrostatic Discharge Caution
    8. 12.8 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

9 Application and Implementation

NOTE

Information in the following applications sections is not part of the TI component specification, and TI does not warrant its accuracy or completeness. TI’s customers are responsible for determining suitability of components for their purposes. Customers should validate and test their design implementation to confirm system functionality.

9.1 Application Information

The TPS62134x family of devices are synchronous step-down converters based on the DCS-Control™ topology. The following section discusses the design of the external components to complete the power-supply design for power rails in the Intel Skylake platform.

9.2 Typical Application

TPS62134A TPS62134B TPS62134C TPS62134D TPS62134A_typ_app.gif Figure 4. TPS62134A Typical Application

9.2.1 Design Requirements

The design guideline provides component selection to operate the device within the values listed in the Recommend Operating Conditions section. Meanwhile, the design meets the time and slew rate requirements of the Intel Skylake platform for VCC(IO), VCC(PRIM_CORE), VCC(EDRAM), and VCC(EOPIO) rails. Table 3 lists the components used for the curves in the Application Curves section.

Table 3. List of Components

REFERENCE DESCRIPTION MANUFACTURER
TPS62134x High efficiency step down converter TI
L1 Inductor, 1 µH, XFL4020-102ME Coilcraft
C1 Ceramic capacitor, 22 µF, GRM21BR61E226ME44L Murata
C2 Ceramic capacitor, 47 µF, GRM21BR60J476ME15L Murata
C3 Ceramic capactor, 470 pF, GRM188R71H471KA01D Murata
R3 Resistor, 499 kΩ Standard

9.2.2 Detailed Design Procedure

9.2.2.1 Output Filter Selection

The first step of the design procedure is the selection of the output-filter components. The combinations listed in Table 4 are used to simplify the output filter component selection.

Table 4. Recommended LC Output Filter Combinations(1)

INDUCTOR OUTPUT CAPACITOR
22 µF 47 µF 100 µF 200 µF 400 µF
0.47 µH
1 µH √(2) √ √
2.2 µH
(1) The values in the table are nominal values, including device tolerances.
(2) This LC combination is the standard value and recommended for most applications.

9.2.2.2 Inductor Selection

The inductor selection is affected by several effects such as inductor-ripple current, output-ripple voltage, PWM-to-PSM transition point, and efficiency. In addition, the selected inductor must be rated for appropriate saturation current and DC resistance (DCR). Use Equation 4 to calculate the maximum inductor current under static load conditions.

Equation 4. TPS62134A TPS62134B TPS62134C TPS62134D EQ_IOUTMAX.gif

where

  • I(L)max is the maximum inductor current
  • ΔI(L)max is the maximum peak-to-peak inductor ripple current
  • Lmin is the minimum effective inductor value
  • ƒS is the actual PWM switching frequency

Calculating the maximum inductor current using the actual operating conditions gives the minimum saturation current. A margin of approximately 20% is recommended to be added. The inductor value also determines the load current at which power save mode is entered:

Equation 5. TPS62134A TPS62134B TPS62134C TPS62134D EQ_IOUTPSM.gif

Table 5 lists inductors that are recommended to use with the TPS62134x device.

Table 5. List of Inductors

TYPE INDUCTANCE (µH) CURRENT (A) DIMENSIONS (L × B × H, mm) MANUFACTURER
XFL4020-102ME 1 µH 4.7 4 × 4 × 2 Coilcraft
DFE252012F 1 µH 5.0 2.5 × 2 × 1.2 Toko
DFE201612E 1 µH 4.1 2 × 1.6 × 1.2 Toko
PISB25201T 1 µH 3.9 2.5 × 2 × 1 Cyntec
PIME031B 1 µH 5.4 3.1 × 3.4 × 1.2 Cyntec

9.2.2.3 Output Capacitor

The recommended value for the output capacitor is 47 µF. The architecture of the TPS62134x family of devices allows the use of tiny ceramic output capacitors which have low equivalent series resistance (ESR). These capacitors provide low output-voltage ripple and are recommended. Using an X7R or X5R dielectric is recommended to maintain low resistance up to high frequencies and to achieve narrow capacitance variation with temperature. Using a higher value can have some advantages such as smaller voltage ripple and a tighter DC output accuracy in PWM. See Optimizing the TPS62130/40/50/60/70 Output Filter, SLVA463 for additional information.

Note that in power save mode, the output voltage ripple depends on the output capacitance, ESR, and peak inductor current. Using ceramic capacitors provides small ESR and low ripple.

9.2.2.4 Input Capacitor

For most applications, using a capacitor with a value of 22 µF is a recommended. Larger values further reduce input-current ripple. The input capacitor buffers the input voltage for transient events and also decouples the converter from the supply. A ceramic capacitor which has low ESR is recommended for best filtering and should be placed between the PVIN and PGND pins and as close as possible to those pins.

9.2.2.5 Soft-Start Capacitor

A capacitor connected between the SS pin and the AGND pin allows a user programmable startup slope of the output voltage. A constant current source supports 2.5 µA to charge the external capacitance. Use Equation 6 to calculate the capacitor value required for a given soft-start time.

Equation 6. TPS62134A TPS62134B TPS62134C TPS62134D EQ_softstart.gif

where

  • C(SS) is the capacitance (F) required at the SS pin
  • t(SS) is the desired soft-start time (s)

Leave the SS pin floating for fastest startup.

9.2.2.6 Program Output Voltage with External Resistor Divider

The TPS62134x family of devices extends the output voltage range by an external resistor divider, shown in Figure 5. The output voltage is then set by Equation 7.

Equation 7. TPS62134A TPS62134B TPS62134C TPS62134D EQ_VOUT.gif

where

  • VFBS is the FBS pin voltage setting by the VIDx pins, as shown in Table 1

The maximum output voltage must be less than 1.9 V. The required feed forward capacitor, C4, improves the loop stability performance. 5 pF is sufficient for most of applications with the R1 and R2 values shown. R1, R2 and C4 must be located close to the IC.

TPS62134A TPS62134B TPS62134C TPS62134D TPS62134A_output_app.gif Figure 5. TPS62134C 1.1-V Output

9.2.3 Application Curves

TA = 25°C and VI = 7.2 V, unless otherwise noted.
TPS62134A TPS62134B TPS62134C TPS62134D D001_SLVSC20.gif
VO = 0.975 V
Figure 6. TPS62134A Efficiency
TPS62134A TPS62134B TPS62134C TPS62134D D003_SLVSC20.gif
VO = 1 V
Figure 8. TPS62134C Efficiency
TPS62134A TPS62134B TPS62134C TPS62134D D008_SLVSC20.gif
VO = 0.95 V VI = 7.2 V
Figure 10. TPS62134A Load Regulation
TPS62134A TPS62134B TPS62134C TPS62134D D007_SLVSC20.gif
VO = 0.975 V
Figure 12. TPS62134A Switching Frequency
TPS62134A TPS62134B TPS62134C TPS62134D D011_SLVSC20_TPS62134.gif
VO = 0.95 V IO = 2 A
Figure 14. TPS62134A Output Ripple
TPS62134A TPS62134B TPS62134C TPS62134D D012_SLVSC20_TPS62134.gif
VO = 0.95 V
Figure 16. TPS62134A Load Transient
TPS62134A TPS62134B TPS62134C TPS62134D D015_SLVSC20_TPS62134.gif
R(LOAD) = 0.47 Ω
Figure 18. TPS62134C Minimum Speed Mode (MSM) Entry and Exit
TPS62134A TPS62134B TPS62134C TPS62134D D016_SLVSC20.gif
VO = 0.95 V
Figure 7. TPS62134B Efficiency
TPS62134A TPS62134B TPS62134C TPS62134D D004_SLVSC20.gif
VO = 0.8 V
Figure 9. TPS62134C Efficiency
TPS62134A TPS62134B TPS62134C TPS62134D D009_SLVSC20.gif
VO = 0.95 V IO = 1 A
Figure 11. TPS62134A Line Regulation
TPS62134A TPS62134B TPS62134C TPS62134D D010_SLVSC20_TPS62134.gif
VO = 0.95 V IO = 50 mA
Figure 13. TPS62134A Output Ripple
TPS62134A TPS62134B TPS62134C TPS62134D D013_SLVSC20_TPS62134.gif
VO = 0.95 V R(LOAD) = 0.47 Ω
Figure 15. TPS62134A Startup and Shutdown
TPS62134A TPS62134B TPS62134C TPS62134D D014_SLVSC20_TPS62134.gif
R(LOAD) = 0.47 Ω
Figure 17. TPS62134C LPM Entry and Exit