SNOSB87D March   2011  – May 2019 LM21215A

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
    1.     Efficiency at 2.5 V, 500 kHz
  3. 3 Description
    1.     Typical Application Circuit
      1.      Device Images
  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 Precision Enable
      2. 7.3.2 Input Voltage UVLO
      3. 7.3.3 Soft-Start Capability
      4. 7.3.4 PGOOD Indicator
      5. 7.3.5 Frequency Synchronization
      6. 7.3.6 Current Limit
      7. 7.3.7 Short Circuit Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Light-Load Operation
      2. 7.4.2 Overvoltage and Undervoltage Handling
      3. 7.4.3 Thermal Shutdown
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Typical Application 1
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Custom Design With WEBENCH® Tools
          2. 8.2.1.2.2 Output Voltage Setpoint
          3. 8.2.1.2.3 Precision Enable
          4. 8.2.1.2.4 Filter Inductor Selection
          5. 8.2.1.2.5 Output Capacitor Selection
          6. 8.2.1.2.6 Input Capacitor Selection
          7. 8.2.1.2.7 Control Loop Compensation
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Typical Application 2
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Compact PCB Layout for EMI Reduction
      2. 10.1.2 Thermal Design
      3. 10.1.3 Ground Plane Design
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
      2. 11.1.2 Development Support
        1. 11.1.2.1 Custom Design With WEBENCH® Tools
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

8.2.2.2 Detailed Design Procedure

Follow the detailed design procedure in Typical Application 1. The relevant power stage and small-signal components are listed in Table 3.

Table 3. Bill of Materials (VIN = 4 V to 5.5 V, VOUT = 0.9 V, IOUT = 8 A, FSW = 1 MHz)

REF DES DESCRIPTION VENDOR PART NUMBER QUANTITY
CF CAP, CERM, 1 µF, 10 V, ±10%, X7R, 0603 MuRata GRM188R71A105KA61D 1
CIN1, CO1, CO2 CAP, CERM, 100 µF, 6.3 V, ±20%, X5R, 1206 MuRata GRM31CR60J107ME39L 3
CC1 CAP, CERM, 1800 pF, 50 V, ±5%, C0G/NP0, 0603 MuRata GRM1885C1H182JA01D 1
CC2 CAP, CERM, 68 pF, 50 V, ±5%, C0G/NP0, 0603 TDK C1608C0G1H680J 1
CC3 CAP, CERM, 470 pF, 50 V, ±5%, C0G/NP0, 0603 TDK C1608C0G1H471J 1
CSS CAP, CERM, 0.033 µF, 16 V, ±10%, X7R, 0603 MuRata GRM188R71C333KA01D 1
LF Inductor, Shielded Core, 240 nH, 20 A, 1 mΩ, SMD Würth 744314024 1
RF RES, 1 Ω, 5%, 0.1 W, 0603 Vishay Dale CRCW06031R00JNEA 1
RC1 RES, 4.87 kΩ, 1%, 0.1 W, 0603 Vishay Dale CRCW06034K87FKEA 1
RC2 RES, 210 Ω, 1%, 0.1 W, 0603 Vishay Dale CRCW0603210RFKEA 1
REN1, RFB1, RPGOOD RES, 10 kΩ, 1%, 0.1 W, 0603 Vishay Dale CRCW060310K0FKEA 3
REN2 RES, 19.6 kΩ, 1%, 0.1 W, 0603 Vishay Dale CRCW060319K6FKEA 1
RFB2 RES, 20 kΩ, 1%, 0.1 W, 0603 Vishay Dale CRCW060320K0FKEA 1
U1 LM21215A Synchronous Buck Regulator TI LM21215AMH-1/NOPB 1