SLLS822B July   2007  – July 2021 TRSF3221E

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  ESD Ratings, IEC Specifications
    4. 6.4  Recommended Operating Conditions
    5. 6.5  Thermal Resistance Characteristics
    6. 6.6  Electrical Characteristics
    7. 6.7  Electrical Characteristics, Driver
    8. 6.8  Switching Characteristics, Driver
    9. 6.9  Electrical Characteristics, Receiver
    10. 6.10 Switching Characteristics, Receiver
    11. 6.11 Electrical Characteristics, Auto-Powerdown
    12. 6.12 Switching Characteristics, Auto-Powerdown
    13. 6.13 Typical Characteristics
  7. 7 Parameter Measurement Information
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
    4. 8.4 Device Functional Modes
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Typical Application
        1. 9.1.1.1 Design Requirements
        2. 9.1.1.2 Detailed Design Procedure
      2. 9.1.2 Application Performance Plot
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Receiving Notification of Documentation Updates
    2. 12.2 Support Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

8.3 Feature Description

The power block increases, inverts, and regulates voltage at V+ and V– pins using a charge pump that requires four external capacitors. Auto-power-down feature for driver is controlled by FORCEON and FORCEOFF inputs. Receiver is controlled by EN input. When MAX3221E is unpowered, it can be safely connected to an active remote RS-232 device.

The driver interfaces the standard logic level to RS232 voltage levels. The DIN input must be valid high or low.

The receiver interfaces RS-232 levels to standard logic levels. An open input results in a high output on ROUT. RIN input includes an internal standard RS-232 load. A logic high input on the EN pin shuts down the receiver output.