Electronic Design

  
Reprints     Printer-Friendly    Email this Article    RSS        Font Size     What's This?


[TechView: Analog & Power]
Efficient PWM Controller IC Bound For Notebook Computers

Roger Allan  |   ED Online ID #8020  |   May 24, 2004


Designers of notebooks and other battery-powered applications on the hunt for ways to simplify design, reduce component count, and lower overall cost should look at a novel pulse-width-modulated (PWM) controller. Among other features, the advanced multi-output voltage SC1404 offers 95% efficiency.

The SC1404 accepts inputs from 6 to 30 V dc. Its two synchronous PWM switching power-supply controllers are preset to generate independent 3.3-V and 5-V supplies. The IC also supplies a 12-V, 200-mA linear regulated output to accommodate the power requirements of many legacy notebook and embedded PC designs.

The two PWM controllers switch out-of-phase to provide ripple cancellation at the input supply, drastically reducing input capacitance filtering requirements. The IC's control loop can also be externally compensated, reducing the amount of output capacitance requirements.

Semtech's proprietary Virtual Current Sense technology provides peak current-mode control. This control is based on a synthetically generated current sense signal that's an order of magnitude larger than the signal generated by conventional current-sensing means.

Quiescent power consumption is 6 mW, standby current is 250 µA, and total supply current in shutdown is 4 µA. The user can select 200-kHz operation (for best efficiency) or 300-kHz operation (for minimal ripple, fast transient response, and/or small output filter component size).

Line and load regulation is 0.08%/V and −0.6%/V, respectively. Other features include overcurrent, overvoltage, and overtemperature protection as well as undervoltage lockout. A 5-V linear regulator can deliver up to 50 mA in standby.

In 1000-unit lots, the SC1404 is priced at $4.05 each for a TSSOP-28 package and $3.95 each for a SSOP-28 package.

Semtech Corp.

www.semtech.com
(805) 498-2111

See associated figure


Reprints   Printer-Friendly  Email this Article  RSS    Font Size   What's This?


  • Engineers Rely On Internet For Product Info
  • Rochester Electronics Establishes New Design and Technology Group
  • Custom Sources Light Way To 22-nm IC Lithography
  • In EDA, A Year Of Mergers, Failed And Otherwise
  • Software Turns Scopes Into Vector RF Signal Analyzers
  • Couple’s $15 Million Gift Advances Rice Engineering Education
  • November 7, 2008
  • Startup Sets Sail For Speedier Spice Simulation
    1) Ten Top Design Skills For Tough Times
    (2496 views today)
    2) Build A Smart Battery Charger Using A Single-Transistor Circuit
    (313 views today)
    3) Energy Harvester Perpetually Powers WIreless Sensors
    (273 views today)
    4) Ultracapacitors Branch Out Into Wider Markets
    (243 views today)
    5) Easily Convert Decimal Numbers To Their Binary And BCD Formats
    (162 views today)
    ALL TOP 20



    POST YOUR COMMENTS HERE
    Name:

    Email:
    Your Comments:

    Enter the text from the image below


    Please refresh the page if you have trouble reading this text.

    Search Electronic Design
         
      
     
    Email Newsletter
    Sponsored By:
    The Find Power Products monthly newsletter brings you the most important new developments within the world of power design. The newsletter includes exerpts from industry leader Sam Davis's exclusive blog, as well as overviews of the latest new products.

    Enter Email to Subscribe
      
    Web Seminar
    Sponsored By:
    Title: Exploring How Good GUIs Drive Adoption in the Digital Power Management Space
    Speakers: Don Tuite Deepak Savadaatt
    Date: 10/24/07
    Register: 

    Electronic Design Europe Electronic Design China EEPN Power Electronics Auto Electronics Microwaves & RF
    Mobile Dev & Design Schematics Find Power Products Military Electronics EE Events Related Resources