SBVS252B October   2014  – February 2019 TPS735-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Typical Application
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin 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 Internal Current-Limit
      2. 7.3.2 Shutdown
      3. 7.3.3 Dropout Voltage
      4. 7.3.4 Startup and Noise Reduction Capacitor
      5. 7.3.5 Transient Response
      6. 7.3.6 Undervoltage Lockout (UVLO)
      7. 7.3.7 Minimum Load
    4. 7.4 Device Functional Modes
      1. 7.4.1 Normal Operation
      2. 7.4.2 Dropout Operation
      3. 7.4.3 Disabled
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
        1. 8.2.1.1 Input and Output Capacitor Requirements
        2. 8.2.1.2 Feedback Capacitor Requirements (TPS73501-Q1 only)
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Output Noise
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Board Layout Recommendations to Improve PSRR and Noise Performance
      2. 10.1.2 Thermal Protection
      3. 10.1.3 Package Mounting
      4. 10.1.4 Power Dissipation
      5. 10.1.5 Estimating Junction Temperature
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Device Nomenclature
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Community Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.4 Startup and Noise Reduction Capacitor

Fixed voltage versions of the TPS735-Q1 family of devices use a quick-start circuit to fast-charge the noise reduction capacitor, CNR, if present (see the Functional Block Diagram section). This architecture allows the combination of very-low output noise and fast startup times. The NR pin is high impedance so a low-leakage CNR capacitor must be used. Most ceramic capacitors are appropriate in this configuration. A high-quality, COG-type (NPO) dielectric ceramic capacitor is recommended for CNR when used in environments where abrupt changes in temperature can occur.

Note that for fastest start-up, apply VIN first, then drive the enable pin (EN) high. If the EN pin is tied to the IN pin, start-up is somewhat slower. Refer to the Typical Application section (see Figure 17 and Figure 18). The quick-start switch is closed for approximately 135 μs. To ensure that CNR is charged during the quick-start time, use a capacitor with a value of no more than 0.01 μF.