SLVSAC4B November   2010  – December 2015 TLV62065

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 Mode Selection
      2. 7.3.2 Enable
      3. 7.3.3 Undervoltage Lockout
      4. 7.3.4 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Soft-Start
      2. 7.4.2 Power-Save Mode
        1. 7.4.2.1 100% Duty Cycle Low Dropout Operation
      3. 7.4.3 Internal Current Limit / Fold-back Current Limit for Short-Circuit Protection
      4. 7.4.4 Output Capacitor Discharge
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Output Voltage Setting
        2. 8.2.2.2 Output Filter Design (Inductor and Output Capacitor)
          1. 8.2.2.2.1 Inductor Selection
          2. 8.2.2.2.2 Output Capacitor Selection
          3. 8.2.2.2.3 Input Capacitor Selection
        3. 8.2.2.3 Checking Loop Stability
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Community Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

10 Layout

10.1 Layout Guidelines

As for all switching power supplies, the layout is an important step in the design. Proper function of the device demands careful attention to PCB layout. Take care in board layout to get the specified performance. If the layout is not carefully done, the regulator could show poor line and/or load regulation, stability issues as well as EMI and thermal problems. It is critical to provide a low inductance, impedance ground path. Therefore, use wide and short traces for the main current paths. The input capacitor should be placed as close as possible to the IC pins as well as the inductor and output capacitor.

Connect the AGND and PGND pins of the device to the exposed thermal pad land of the PCB and use this pad as a star point. Use a common power PGND node and a different node for the signal AGND to minimize the effects of ground noise. The FB divider network should be connected right to the output capacitor and the FB line must be routed away from noisy components and traces (for example, SW line).

Due to the small package of this converter and the overall small solution size, the thermal performance of the PCB layout is important. For good thermal performance a four or more layer PCB design is recommended. The exposed thermal pad of the IC must be soldered on the power pad area on the PCB to achieve proper thermal connection. Additionally, for good thermal performance, the exposed thermal pad on the PCB needs to be connected to an inner GND plane with sufficient via connections. See the documentation of the evaluation kit.

10.2 Layout Example

TLV62065 pcb_layout_lvsac4.gif Figure 24. PCB Layout