SBVS361A April   2020  – November 2020 TPS7B84-Q1

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  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. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagrams
    3. 7.3 Feature Description
      1. 7.3.1 Enable (EN)
      2. 7.3.2 Undervoltage Lockout
      3. 7.3.3 Thermal Shutdown
      4. 7.3.4 Current Limit
    4. 7.4 Device Functional Modes
      1. 7.4.1 Device Functional Mode Comparison
      2. 7.4.2 Normal Operation
      3. 7.4.3 Dropout Operation
      4. 7.4.4 Disabled
  8. Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Input and Output Capacitor Selection
      2. 8.1.2 Adjustable Device Feedback Resistor Selection
      3. 8.1.3 Feed-Forward Capacitor (CFF)
      4. 8.1.4 Dropout Voltage
      5. 8.1.5 Reverse Current
      6. 8.1.6 Power Dissipation (PD)
        1. 8.1.6.1 Thermal Performance Versus Copper Area
        2. 8.1.6.2 Power Dissipation vs Ambient Temperature
      7. 8.1.7 Estimating Junction Temperature
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Input Capacitor
        2. 8.2.2.2 Output Capacitor
      3. 8.2.3 Application Curves
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Package Mounting
      2. 10.1.2 Board Layout Recommendations to Improve PSRR and Noise Performance
    2. 10.2 Layout Examples
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Device Nomenclature
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • DCY|4
  • DRB|8
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Board Layout Recommendations to Improve PSRR and Noise Performance

As depicted in Figure 10-1 and Figure 10-2, place the input and output capacitors close to the device for the layout of the TPS7B84-Q1. In order to enhance the thermal performance, place as many vias as possible around the device. These vias improve the heat transfer between the different GND planes in the PCB.

To improve ac performance such as PSRR, output noise, and transient response, TI recommends a board design with separate ground planes for IN and OUT, with each ground plane connected only at the GND pin of the device. In addition, the ground connection for the output capacitor must connect directly to the GND pin of the device.

Minimize equivalent series inductance (ESL) and ESR in order to maximize performance and ensure stability. Place each capacitor as close as possible to the device and on the same side of the PCB as the regulator itself.

Do not place any of the capacitors on the opposite side of the PCB from where the regulator is installed. TI strongly discourages the use of vias and long traces to connect the capacitors because these can negatively impact system performance and may even cause instability.

If possible, and to ensure the maximum performance specified in this document, use the same layout pattern used for the TPS7B84-Q1 evaluation board, available at www.ti.com.