SLLS723D April   2006  – February 2024 MAX232E

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1  Absolute Maximum Ratings
    2. 5.2  ESD Ratings
    3. 5.3  Recommended Operating Conditions
    4. 5.4  Thermal Information
    5. 5.5  Electrical Characteristics
    6. 5.6  Electrical Characteristics: Driver
    7. 5.7  Electrical Characteristics: Receiver
    8. 5.8  Switching Characteristics: Driver
    9. 5.9  Switching Characteristics: Receiver
    10. 5.10 Typical Characteristics
  7.   17
  8. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Power
      2. 6.3.2 RS-232 Driver
      3. 6.3.3 RS-232 Receiver
    4. 6.4 Device Functional Modes
      1. 6.4.1 VCC Powered by 5V
      2. 6.4.2 VCC Unpowered
      3. 6.4.3 Truth Tables
  9. 7 Applications and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
      3. 7.2.3 Application Curve
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  10. 8 Device and Documentation Support
    1. 8.1 Receiving Notification of Documentation Updates
    2. 8.2 Support Resources
    3. 8.3 Trademarks
    4. 8.4 Electrostatic Discharge Caution
    5. 8.5 Glossary
  11. 9 Revision History
  12. 10Mechanical, Packaging, and Orderable Information

Package Options

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

7.2.2 Detailed Design Procedure

The capacitor type used for C1–C4 is not critical for proper operation. The MAX232E requires 1µF capacitors, although capacitors up to 10µF can be used without harm. Ceramic dielectrics are suggested for capacitors. When using the minimum recommended capacitor values, make sure the capacitance value does not degrade excessively as the operating temperature varies. If in doubt, use capacitors with a larger (for example, 2×) nominal value. The capacitors' effective series resistance (ESR), which usually rises at low temperatures, influences the amount of ripple on V+ and V–.

Use larger capacitors (up to 10µF) to reduce the output impedance at VS+ and VS–.

Bypass VCC to ground with at least 1 µF. In applications sensitive to power-supply noise generated by the charge pumps, decouple VCC to ground with a capacitor the same size as (or larger than) the charge-pump capacitors (C1–C4).