SNVSCS6A March   2026  – August 2026 TPS7H1301-SP

PRODMIX  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Options Table
  6. 5 Device Comparison Table
  7. 6 Pin Configuration and Functions
  8. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Quality Conformance Inspection
    7. 7.7 Typical Characteristics
  9. 8 Parameter Measurement Information
  10. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  Enable
      2. 9.3.2  Charge Pump
        1. 9.3.2.1 Charge Pump Operation
        2. 9.3.2.2 Foldback Switching
      3. 9.3.3  Startup
      4. 9.3.4  Power Good
      5. 9.3.5  Output Voltage
      6. 9.3.6  Dropout
      7. 9.3.7  Output Voltage Accuracy
      8. 9.3.8  Output Noise
      9. 9.3.9  Power Supply Rejection Ratio
      10. 9.3.10 Stability
        1. 9.3.10.1 Stability of the TPS7H1301
        2. 9.3.10.2 Stability of the TPS7H1302
      11. 9.3.11 Thermal Shutdown
    4. 9.4 Device Functional Modes
      1. 9.4.1 Enable Disable
  11. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application TPS7H1301
      1. 10.2.1 Design Requirements TPS7H1301
      2. 10.2.2 Detailed Design Procedure TPS7H1301
        1. 10.2.2.1 Capacitor Selection
          1. 10.2.2.1.1 Input Capacitor (CIN) Selection
          2. 10.2.2.1.2 CFLY TPS7H1301
          3. 10.2.2.1.3 CPOUT Capacitor TPS7H1301
          4. 10.2.2.1.4 Bypass Capacitors
          5. 10.2.2.1.5 Output Capacitor
        2. 10.2.2.2 Charge Pump Output Resistance
        3. 10.2.2.3 Configuring LDO Output
        4. 10.2.2.4 Output Noise
        5. 10.2.2.5 PSRR Design Implications
        6. 10.2.2.6 Stability Design Considerations
      3. 10.2.3 Application Curves
    3. 10.3 Typical Application TPS7H1301 Parallel Operation
      1. 10.3.1 Design Requirements
      2. 10.3.2 Detailed Design Procedure Parallel TPS7H1301
        1. 10.3.2.1 Parallel Ballast Resistor
      3. 10.3.3 Application Performance Plots
    4. 10.4 Typical Application TPS7H1302
      1. 10.4.1 Design Requirements TPS7H1302
      2. 10.4.2 Detailed Design Procedure TPS7H1302
        1. 10.4.2.1 Capacitor Selection TPS7H1302
        2. 10.4.2.2 CFLY Capacitor TPS7H1302
        3. 10.4.2.3 CPOUT Capacitor TPS7H1302
        4. 10.4.2.4 Stability TPS7H1302
      3. 10.4.3 TPS7H1302 Application Performance Plots
    5. 10.5 TPS7H1302 Low Noise Configuration
      1. 10.5.1 Design Requirements TPS7H1302 Low Noise
      2. 10.5.2 Application Performance Plots
    6. 10.6 Power Supply Recommendations
    7. 10.7 Layout
      1. 10.7.1 Layout Guidelines
      2. 10.7.2 Layout Example
  12. 11Device and Documentation Support
    1. 11.1 Device Support
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Support Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  13. 12Revision History
  14. 13Mechanical, Packaging, and Orderable Information
    1.     PACKAGE OPTION ADDENDUM
    2. 13.1 Tube Information
    3.     88
10.2.2.1.2 CFLY TPS7H1301

CFLY is the charge pump capacitor that transfers charge from the input to the charge pump output (CPOUT pin).

For typical high-current applications, TI recommends at a minimum a nominally rated 1μF ceramic output capacitor for stable operation. Polarized capacitors (tantalum, aluminum, electrolytic, and so forth) must not be used for the flying capacitor, as polarized capacitors can become reverse-biased during operation.

If CFLY is sized too small, the charge pump is unable to support high current applications; conversely if CFLY is too large, the charge pump current becomes excessive for the charge pump switches and causes increased input and output voltage ripple.

Sizing CFLY

Size CFLY to a nominal ratio of 1:10 to 1:2 of the charge pump output capacitance CCPOUT.

Use Equation 9 to size CFLY, fSW is 500kHz (typ.) and ΔVCFLY takes into account voltage overshoot at the CFLY capacitor nodes. For applications with nominal VIN conditions 5V or lower and output currents below 250mA, using a factor of 0.2 in Equation 10 is sufficient; as VIN and IOUT increase above 5V or 250mA the ΔVCFLY needs to be adjusted lower (apply a factor of 0.1), which aids in preventing excessive overshoot on pin C+ and C-.

Equation 9. C F L Y =   I O U T f S W × Δ V C F L Y
Equation 10. ΔVCFLY=(0.1 to 0.2)×VIN

Applying Equation 9 yields the following:

Equation 11. CFLY= 250mA500kHz×0.2=2.5µF

The result of Equation 11 is 2.5μF which satisfies the CFLY to CCPOUT ratio, for this Detailed Design Procedure example, 1μF is selected to align with characterization data in the Section 7.5 table which is a more onerous configuration as a 1μF lowers LDO headroom vs. a 2.5μf at CFLY.

Effects of CFLY

Dropout Current and charge pump operational efficiency are reliant on the charge pump resistance and voltage droop, which is directly affected by the choice of CFLY; selecting a capacitor that is too small or too high ESR increases charge pump output resistance, such that the resulting voltage droop lowers the available headroom for the integrated LDO and reduces overall charge pump efficiency; refer to Figure 7-8 through Figure 7-12 to see how CFLY selection changes the charge pump efficiency.

Consideration of CFLY capacitor characteristics, such as DC bias, temperature coefficient are essential in assessing the contribution of the capacitor to charge pump resistance; Equation 12 calculates the fly capacitors contribution to the overall charge pump output resistance and VDROOP. Note, that the min switching frequency (fSW) from the Electrical Characteristics table is the more conservative estimation parameter; as min fSW results in a higher charge pump resistance.

Equation 12. RCFLY=1fSW×CCFLYmin+4×RESRCFLY

As Equation 12 shows, a typical reduction in output capacitance due to DC Bias and temperature typically reduces overall CFLY capacitance by 15% to 25% and thus increases charge pump output resistance.

To calculate CFLY(min) consult the capacitor manufacturer data and apply the overall tolerance, DC Bias, and temperature derating: For example, a 25V 1μF X7R capacitor with the following parameters:

  • Case Size: 0805
  • Tolerance: -5%
  • DC Bias @ 5V: -4.56%
  • Temperature derating @ 125ºC: -14.56%
  • RESR @ 400kHz: 10mΩ

Table 10-2 is an example tradeoff for selecting either a solitary 1μF (nom.) capacitor or a 2.2μF (nom) capacitors; the overall contribution of CFLY to the resistance of the charge pump is compared against overall charge pump efficiency.

Table 10-2 CFLY Comparison
Attribute 1μF 2.2μF
Part Number KGM21AR71C105JL KGM21AR71C225KL
QTY 1 1
Case Size 0805 0805
Voltage Rating 16V 16V
Dielectric X7R X7R
Derating Parameters
Tolerance -5% -10%
DC Bias @ 5V -4.56% -10.3%
Tempco. @ 125ºC -14.56% -15%
Results
Effective Capacitance 0.775μF 1.51μF
ESR 10mΩ 10mΩ (effective res.)
RCFLY 3.45Ω 1.69Ω
Peak charge pump efficiency, VIN = 5V 79% 83.5%

To calculate the minimum capacitance for CFLY use :

Equation 13. C F L Y ( m i n ) =   C F L Y ( n o m ) × T o l . × D C   B i a s × T e m p

Applying Equation 13 for the 1μF (nom.) capacitor:

Equation 14. C F L Y ( m i n ) = 1 µ F × 1 - 0.05 × 1 - 0.0456 × 1 - 0.1456 = 0.775 µ F

The worst case contribution of CFLY is calculated by applying Equation 12 (1μF (nom.) example)

Equation 15. RCFLY= 1400kHz×0.775µF+4×10mΩ=3.45Ω

Table 10-2 shows that the additional component count of the two 0.68μF capacitors offers a significant reduction in the contribution of CFLY to overall charge pump output resistance. Applications at higher operating temperatures, operating currents, or lower VIN benefit from more from overall lower charge pump output resistance. This design examples uses a VIN of 5V and a ILOAD of 250mA is sufficiently served by the 1μF CFLY capacitor.

Overall the selected value for CFLY, affects charge pump resistance and charge pump efficiency; refer to figures Figure 7-8 to Figure 7-11 to see how CFLY selection affects overall charge pump efficiency.