SNVS416C November   2005  – February 2016 LM27951

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 Charge Pump
      2. 7.3.2 Soft Start
      3. 7.3.3 Thermal Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Enable and PWM Pins
      2. 7.4.2 Adjusting LED Brightness (PWM Control)
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Maximum Output Current, Maximum LED Voltage, Minimum Input Voltage
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Setting LED Currents
        2. 8.2.2.2 Capacitor Selection
        3. 8.2.2.3 Parallel Dx Outputs for Increased Current Drive
        4. 8.2.2.4 Power Efficiency
        5. 8.2.2.5 Power Dissipation
      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 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

5 Pin Configuration and Functions

NHK Package
14-Pin WSON
Top View
LM27951 pinout_top_snvs416.gif
NHK Package
14-Pin WSON
Bottom View
LM27951 pinout_bottom_snvs416.gif

Pin Functions

PIN TYPE DESCRIPTION
NUMBER NAME
1 C2+ Power Flying capacitor C2 connection
2 VOUT Power Pre-regulated charge-pump output
3 C1+ Power Flying capacitor C1 connection
4 D4 Output Regulated current source output
5 D3 Output Regulated current source output
6 D2 Output Regulated current source output
7 D1 Output Regulated current source output
8 ISET Input Current set input. Placing a resistor (RSET) between this pin and GND sets the LED current for all the LEDs. LED current = 200 × (1.25 V / RSET).
9 EN Input Enable logic input pin. Logic low = shutdown; Logic high = enabled. There is a 150-kΩ (typical) resistor connected internally between the EN pin and GND.
10 PWM Input Current source modulation logic input pin. Logic low = Off; Logic high = On.
Applying a pulse width modulated (PWM) signal to this pin allows the regulated current sources to be modulated without shutting down the internal charge pump and the VOUT node.
11 VIN Input Input supply: 2.8 V to 5.5 V
12 C2- Power Flying capacitor C2 connection
13 GND Ground Power supply ground connection
14 C1- Power Flying capacitor C1 connection