SLUSF98 November   2024 TPSM84338

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1  Fixed Frequency Peak Current Mode
      2. 6.3.2  Mode Selection
      3. 6.3.3  Voltage Reference
      4. 6.3.4  Output Voltage Setting
      5. 6.3.5  Switching Frequency Selection, Synchronization
      6. 6.3.6  Phase Shift
      7. 6.3.7  Enable and Adjusting Undervoltage Lockout
      8. 6.3.8  External Soft Start and Prebiased Soft Start
      9. 6.3.9  Power Good
      10. 6.3.10 Minimum On Time, Minimum Off Time, and Frequency Foldback
      11. 6.3.11 Frequency Spread Spectrum
      12. 6.3.12 Overvoltage Protection
      13. 6.3.13 Overcurrent and Undervoltage Protection
      14. 6.3.14 Thermal Shutdown
    4. 6.4 Device Functional Modes
      1. 6.4.1 Modes Overview
      2. 6.4.2 Heavy Load Operation
      3. 6.4.3 Pulse Frequency Modulation
      4. 6.4.4 Forced Continuous Conduction Modulation
      5. 6.4.5 Dropout Operation
      6. 6.4.6 Minimum On-Time Operation
      7. 6.4.7 Shutdown Mode
  8. 7 Application and Implementation
    1. 7.1 Typical Application
      1. 7.1.1 Design Requirements
      2. 7.1.2 Detailed Design Procedure
        1. 7.1.2.1 Custom Design With WEBENCH® Tools
        2. 7.1.2.2 Output Voltage Resistors Selection
        3. 7.1.2.3 Choosing Switching Frequency
        4. 7.1.2.4 Soft-Start Capacitor Selection
        5. 7.1.2.5 Output Capacitor Selection
        6. 7.1.2.6 Input Capacitor Selection
        7. 7.1.2.7 Feedforward Capacitor CFF Selection
        8. 7.1.2.8 Maximum Ambient Temperature
      3. 7.1.3 Application Curves
    2. 7.2 Best Design Practices
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Third-Party Products Disclaimer
      2. 8.1.2 Development Support
        1. 8.1.2.1 Custom Design With WEBENCH® Tools
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

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

4 Pin Configuration and Functions

TPSM84338 9-Pin RCJ QFN-FCMOD, 3.3mm × 4.5mm Package (Top View)Figure 4-1 9-Pin RCJ QFN-FCMOD, 3.3mm × 4.5mm Package (Top View)
Table 4-1 Pin Functions
PINTYPE(1)DESCRIPTION
NAMENO.
EN1AEnable input to the converter. Driving EN high or leaving this pin floating enables the converter. An external resistor divider can be used to implement an adjustable VIN UVLO function.
FB2AOutput feedback input. Connect FB to the tap of an external resistor divider from the output to GND to set output voltage.
GND3GGround pin. Connected to the source of the low-side FET as well as the ground pin for the controller circuit. Connect to system ground and the ground side of CIN and COUT. The path to CIN must be as short as possible.
VOUT 4 P Output voltage. This pin is connected to the internal buck inductor. Connect the pin to the output load and connect external output capacitors between this pin and GND.
SW 5 P Switching node. Do not place any external component on this pin or connect to any signal. The amount of copper placed on this pin must be kept to a minimum to prevent issues with noise and EMI.
VIN6PSupply input pin to internal LDO and high-side FET. Input bypass capacitors must be directly connected to this pin and GND.
MODE7AMode selection pin in light load condition and Power-Good / Soft-Start function. See Mode Selection for details.
SS/PG8AThis pin can be a soft-start function or Power-Good function depending on the mode pin configuration. If the soft-start function is selected, an external capacitor connected from this pin to GND defines the rise time for the internal reference voltage. If Power-Good function is selected, this is an open drain power-good indicator, which is asserted low if output voltage is out of PG threshold, overvoltage, or if the device is under thermal shutdown, EN shutdown, or during soft start.
RT/SYNC 9 A Frequency select and external clock synchronization. A resistor to ground sets the switching frequency of the device. An external clock can also be applied to this pin to synchronize the switching frequency. See Section 6.3.5 for details.
(1) A = Analog, P = Power, G = Ground