ENGLISH 简体中文 日本語 한국어  

MAX1940
Triple USB Switch with Autoreset and Fault Blanking


  QuickView     Technical Documents     Ordering Info     More Information     All  
Description
FULL DATA SHEET (PDF, 332kB)
Download this datasheet in PDF formatDownload   Send this datasheet to any email addressE-Mail


The MAX1940 triple current-limited switch with auto-reset supplies a guaranteed 500mA load per channel in accordance with USB specifications. The MAX1940 operates from a 4V to 5.5V input supply and consumes only 60µA of quiescent current when operating and only 3µA in standby. Selectable active-high/active-low control logic and independent shutdown controls for each channel provide additional flexibility. An autoreset feature latches the switch off in the event of a short circuit, saving system power. The switch reactivates upon removal of the shorted condition.

The MAX1940 provides several safety features to protect the USB port. Built-in thermal-overload protection turns off the switch when the die temperature exceeds +160°C. Accurate internal current-limiting circuitry protects the input supply against both overload and short-circuit conditions. Independent open-drain fault signals (active-low FAULTA, active-low FAULTB, and active-low FAULTC) notify the microprocessor when a thermal-overload, current-limit, undervoltage lockout (UVLO), or short-circuit fault occurs. A 20ms fault-blanking feature enables the circuit to ignore momentary faults, such as those caused when hot-swapping a capacitive load, preventing false alarms to the host system. The fault-blanking feature also prevents fault signals from being issued when the device powers up the load.

The MAX1940 is available in a space-saving 16-pin QSOP package and operates over the extended (-40°C to +85°C) temperature range.

Key Features   Applications/Uses
  • Triple USB Switch in Tiny 16-Pin QSOP Package
  • Autoreset Feature Saves System Power
  • Guaranteed 500mA Load Current per Channel
  • Built-In 20ms Fault-Blanking Circuitry
  • Active-High/Active-Low Control Logic
  • Fully Compliant to USB Specifications
  • 4V to 5.5V Input Voltage Range
  • Independent Shutdown Control
  • Independent Fault Indicator Outputs
  • Thermal-Overload Protection
  • 3µA Standby Current
  • UL Certification Pending

     
  • Computers: Desktop, Workstation, Server
  • Docking Stations
  • Notebook Computers
  • PDAs and Palmtop Computers
  • USB Hubs
  • USB Ports

    Key Specifications:   USB Power Switches
    Part Number Functions Number of Switches Max. Load Current (A) RON (typ) (Ω) Fault Indicator Fault Blanking Timeout (ms) Switch Op. Voltage Range (V) RoHS Available Package Smallest Available Package (max w/pins) (mm2) Operating Temp. Range (°C) Price**
    MAX1940 
    Active High/Active Low Control Logic
    3 0.5 0.085 Yes 20 4.0 to 5.5 Yes QSOP/16 31 -40 to +85 $1.25 @ 1k
    See All USB Power Switches (28)
    Notes:
    **This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

    Diagram
    MAX1940: Typical Operating Circuit
    Typical Operating Circuit

    Didn't Find What You Need?
  • Next Day Product Selection Assistance from Applications Engineers
  • Parametric Search
  • Applications Help
  •  QuickView   Technical Documents   Ordering Info   More Information  
     Description 
     Key Features 
     Applications/Uses 
     Key Specifications 
     Diagram 

     Data Sheet 
     Application Notes 
     Design Guides 
     Engineering Journals 
     Reliability Reports 
     Software/Models 
     Evaluation Kits 

     Price and Availability 
     Samples 
     Buy Online 
     Package Information 
     Lead-Free Information 

     Related Products 
     Notes and Comments 
     Evaluation Kits 

    Document Ref.: 19-2497; Rev 0; 2002-08-23
    This page last modified: 2007-07-16



          Privacy Policy    Legal Notices

          Copyright © 2008 by Maxim Integrated Products, Dallas Semiconductor


    ">