Maxim > Products > Automotive > MAX3222, MAX3232, MAX3237, ...
Maxim > Products > Interface > MAX3222, MAX3232, MAX3237, ...

MAX3222, MAX3232, MAX3237, MAX3241

3.0V to 5.5V, Low-Power, up to 1Mbps, True RS-232 Transceivers Using Four 0.1µF External Capacitors

 Overview   Design Resources   Ordering Info   Related Products   All   

Status Explanations for product status codes

Part Number Status
MAX3222 Active: In Production. But some versions of the family are Not Recommended for New Designs. See Ordering Information.
MAX3232 Active: In Production.
MAX3237 Active: In Production.
MAX3241 Active: In Production.


The MAX3222/MAX3232/MAX3237/MAX3241 transceivers have a proprietary low-dropout transmitter output stage enabling true RS-232 performance from a 3.0V to 5.5V supply with a dual charge pump. The devices require only four small 0.1µF external charge-pump capacitors. The MAX3222, MAX3232, and MAX3241 are guaranteed to run at data rates of 120kbps while maintaining RS-232 output levels. The MAX3237 is guaranteed to run at data rates of 250kbps in the normal operating mode and 1Mbps in the MegaBaud operating mode, while maintaining RS-232 output levels.

The MAX3222/MAX3232 have 2 receivers and 2 drivers. The MAX3222 features a 1µA shutdown mode that reduces power consumption and extends battery life in portable systems. Its receivers remain active in shutdown mode, allowing external devices such as modems to be monitored using only 1µA supply current. The MAX3222 and MAX3232 are pin, package, and functionally compatible with the industry-standard MAX242 and MAX232, respectively.

The MAX3241 is a complete serial port (3 drivers/5 receivers) designed for notebook and subnotebook computers. The MAX3237 (5 drivers/3 receivers) is ideal for fast modem applications. Both these devices feature a shutdown mode in which all receivers can remain active while using only 1µA supply current. Receivers R1 (MAX3237/MAX3241) and R2 (MAX3241) have extra outputs in addition to their standard outputs. These extra outputs are always active, allowing external devices such as a modem to be monitored without forward biasing the protection diodes in circuitry that may have VCC completely removed.

The MAX3222, MAX3237, and MAX3241 are available in space-saving TSSOP and SSOP packages.

Data Sheet

Download this datasheet in PDF formatDownload Rev 7 (PDF, 459.8kB)
Send this datasheet to any email addressEmail

My Maxim: Not Logged In
By logging in to My Maxim you can subscribe to alerts for this data sheet.

Login | Register
An evaluation board is available: MAXPMBAE

Key Features

  • For Smaller Packaging:
    • MAX3228E/MAX3229E: +2.5V to +5.5V RS-232 Transceivers in UCSP™
  • For Integrated ESD Protection:
    • MAX3222E/MAX3232E/MAX3237E/MAX3241E/MAX3246E: ±15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V, Up to 1Mbps, True RS-232 Transceivers
  • For Low-Voltage or Data Cable Applications:
    • MAX3380E/MAX3381E: +2.35V to +5.5V, 1µA, 2Tx/2Rx RS-232 Transceivers with ±15kV ESD-Protected I/O and Logic Pins


  • Battery-Powered Equipment
  • Handheld Equipment
  • High-Speed Modems
  • Notebook, Subnotebook, and Palmtop Computers
  • Peripherals
  • Printers

Key Specifications:

RS-232 Line Driver/Receivers
Part Number VSUPPLY
Tx Rx Data Rate
Internal Charge Pump Ext. Caps Cap. Value
Rx Active in Shutdn Budgetary
min typ nom See Notes
2 2 120 0.3 Yes 4 0.1 2 $2.39 @1k
MAX3232  2 2 120 0.3 - $2.56 @1k
MAX3237  5 3 1000 0.5 3 $2.23 @1k
MAX3241  3 5 120 0.3 5 $2.23 @1k
See All RS-232 Line Driver/Receivers (152)

Pricing 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 and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

  • MAX242 pinout (MAX3222)
  • Industry standard MAX232 pinout (MAX3232)
  • World's fastest RS-232 transceiver at 1Mbps (MAX3237)
  • Mouse driveability, two spare receivers active in shutdown (MAX3241)

  • Diagram

    MAX3222, MAX3232, MAX3237, MAX3241: Typical Operating Circuits
    Typical Operating Circuits

    More Information

    RS232 Resources

    Didn't Find What You Need?

    Information Index

    Document Ref.: 19-0273 Rev 7; 2007-03-30
    This page last modified: 2014-02-03