SBVS395 July   2022 TPS7A57

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Output Voltage Setting and Regulation
      2. 7.3.2 Low-Noise, Ultra-High Power-Supply Rejection Ratio (PSRR)
      3. 7.3.3 Programmable Soft-Start (NR/SS Pin)
      4. 7.3.4 Precision Enable and UVLO
      5. 7.3.5 Charge Pump Enable and BIAS Rail
      6. 7.3.6 Power-Good Pin (PG Pin)
      7. 7.3.7 Active Discharge
      8. 7.3.8 Thermal Shutdown Protection (TSD)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Normal Operation
      2. 7.4.2 Dropout Operation
      3. 7.4.3 Disabled
      4. 7.4.4 Current-Limit Operation
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1  Precision Enable (External UVLO)
      2. 8.1.2  Undervoltage Lockout (UVLO) Operation
        1. 8.1.2.1 IN Pin UVLO
        2. 8.1.2.2 BIAS UVLO
        3. 8.1.2.3 Typical UVLO Operation
        4. 8.1.2.4 UVLO(IN) and UVLO(BIAS) Interaction
      3. 8.1.3  Dropout Voltage (VDO)
      4. 8.1.4  Input and Output Capacitor Requirements (CIN and COUT)
      5. 8.1.5  Recommended Capacitor Types
      6. 8.1.6  Soft-Start, Noise Reduction (NR/SS Pin), and Power-Good (PG Pin)
      7. 8.1.7  Optimizing Noise and PSRR
      8. 8.1.8  Adjustable Operation
      9. 8.1.9  Load Transient Response
      10. 8.1.10 Current Limit and Foldback Behavior
      11. 8.1.11 Charge Pump Operation
      12. 8.1.12 Sequencing
      13. 8.1.13 Power-Good Functionality
      14. 8.1.14 Output Impedance
      15. 8.1.15 Paralleling for Higher Output Current and Lower Noise
      16. 8.1.16 Current Mode Margining
      17. 8.1.17 Voltage Mode Margining
      18. 8.1.18 Power Dissipation (PD)
      19. 8.1.19 Estimating Junction Temperature
      20. 8.1.20 TPS7A57EVM-081 Thermal Analysis
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  9. 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
  10. 10Mechanical, Packaging, and Orderable Information
    1. 10.1 Mechanical Data

Package Options

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

8.1.8 Adjustable Operation

As shown in Figure 8-8, the output voltage of the device can be set using a single external resistor (RREF).

GUID-20211102-SS0I-6Q48-PCBF-2GXSVHLCDCPF-low.gif Figure 8-8 Typical Circuit

Use Equation 5 to calculate the RREF value needed for the desirable output voltage.

Equation 17. VOUT = IREF(NOM) × RREF

Table 8-4 shows the recommended RREF resistor values to achieve several common rails using a standard 1%-tolerance resistor.

Table 8-4 Recommended RREF Values
TARGETED OUTPUT VOLTAGE (V) RREF (kΩ)(1) CALCULATED OUTPUT VOLTAGE (V)
0.5 10.0 0.500
0.6 12.1 0.605
0.7 14.0 0.700
0.8 16.2 0.810
0.9 18.2 0.910
1.0 20.0 1.000
1.2 24.3 1.215
1.5 30.1 1.505
2.5 49.9 2.495
3.0 60.4 3.020
3.3 66.5 3.325
3.6 71.5 3.575
4.7 95.3 4.765
5.0 100.0 5.000
(1) 1% resistors.