SNVS723G October   2011  – July 2018 LMZ10500

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
    1.     Device Images
      1.      Typical Efficiency at VIN = 3.6 V
      2.      Radiated EMI (CISPR22) VIN = 5 V, VOUT = 1.8 V, IOUT = 650 mA
  4. Revision History
  5. Pin Configuration and Functions
    1.     Pin 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 System Characteristics
    7. 6.7 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Current Limit
      2. 7.3.2 Start-up Behavior and Soft Start
      3. 7.3.3 Output Short Circuit Protection
      4. 7.3.4 Thermal Overload Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Circuit Operation
      2. 7.4.2 Input Undervoltage Detection
      3. 7.4.3 Shutdown Mode
      4. 7.4.4 EN Pin Operation
      5. 7.4.5 Internal Synchronous Rectification
      6. 7.4.6 High Duty Cycle Operation
  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 Custom Design With WEBENCH® Tools
        2. 8.2.2.2 Setting the Output Voltage
          1. 8.2.2.2.1 RT and RB Selection for Fixed VOUT
          2. 8.2.2.2.2 Output Voltage Accuracy Optimization
        3. 8.2.2.3 Dynamic Output Voltage Scaling
        4. 8.2.2.4 Integrated Inductor
        5. 8.2.2.5 Input and Output Capacitor Selection
      3. 8.2.3 Application Curves
        1. 8.2.3.1 VOUT = 1.2 V
        2. 8.2.3.2 VOUT = 1.8 V
        3. 8.2.3.3 VOUT = 2.5 V
        4. 8.2.3.4 VOUT = 3.3 V
  9. Power Supply Recommendations
    1. 9.1 Voltage Range
    2. 9.2 Current Capability
    3. 9.3 Input Connection
      1. 9.3.1 Voltage Drops
      2. 9.3.2 Stability
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Package Considerations
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Custom Design With WEBENCH® Tools
    2. 11.2 Documentation Support
    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

Refer to the PDF data sheet for device specific package drawings

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

RT and RB Selection for Fixed VOUT

The parameters affecting the output voltage setting are the RT, RB, and the product of the VREF voltage × GAIN. The VREF voltage is typically 2.35 V. Since VCON is derived from VREF via RT and RB,

Equation 2. VCON = VREF × RB/ (RB + RT)

After substitution,

Equation 3. VOUT = VREF × GAIN × RB/ (RB + RT)
Equation 4. RT = ( GAIN × VREF / VOUT – 1 ) x RB

The ideal product of GAIN × VREF = 5.875 V.

Choose RT to be between 80 kΩ and 300 kΩ. Then, RB can be calculated using Equation 5.

Equation 5. RB = ( VOUT / (5.875V – VOUT) ) x RT

Note that the resistance of RT should be ≥ 80 kΩ. This ensures that the VREF output current loading is not exceeded and the reference voltage is maintained. The current loading on VREF should not be greater than 30 µA.