AVAILABLE
Functional Diagrams
Pin Configurations appear at end of data sheet.
Functional Diagrams continued at end of data sheet.
UCSP is a trademark of Maxim Integrated Products, Inc.
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.
General Description
The MAX3221E/MAX3223E/MAX3243E are 3V-powered
EIA/TIA-232 and V.28/V.24 communications interfaces
with automatic shutdown/wakeup features, high data-
rate capabilities, and enhanced electrostatic discharge
(ESD) protection. All transmitter outputs and receiver
inputs are protected to ±15kV using IEC 1000-4-2 Air-
Gap Discharge, to ±8kV using IEC 1000-4-2 Contact
Discharge, and to ±15kV using the Human Body Model.
The MAX3221E/MAX3223E/MAX3243E achieve a
1A supply current with Maxim’s revolutionary
AutoShutdown feature. They save power without
changes to the existing BIOS or operating system by enter-
ing low-power shutdown mode when the RS-232 cable is
disconnected, or when the transmitters of the connected
peripherals are off.
The transceivers have a proprietary low-dropout trans-
mitter output stage, delivering true RS-232 performance
from a +3.0V to +5.5V supply with a dual charge pump.
The charge pump requires only four small 0.1F capaci-
tors for operation from a +3.3V supply. Each device is
guaranteed to run at data rates of 250kbps while main-
taining RS-232 output levels.
The MAX3221E contains just one driver and one receiver,
making it the smallest single-supply RS-232 transceiver.
The MAX3223E has two drivers and two receivers. The
MAX3243E is a complete 3-driver/5-receiver serial port
ideal for notebook or subnotebook computers. It also
includes two noninverting receiver outputs that are always
active, allowing external devices to be monitored without
forward biasing the protection diodes in circuitry that may
be powered down.
The MAX3221E, MAX3223E, and MAX3243E are avail-
able in space-saving TQFN, SSOP, and TSSOP pack-
ages.
Applications
Notebook, Subnotebook, and Palmtop Computers
Cellular Phones
Battery-Powered Equipment
Handheld Equipment
Peripherals
Printers
Next Generation Device Features
o For Space-Constrained Applications:
MAX3228E/MAX3229E: ±15kV ESD-Protected, +2.5V
to +5.5V RS-232 Transceivers in UCSP
MAX3222E/MAX3232E/MAX3237E/MAX3241E/
MAX3246E: ±15kV ESD-Protected Down to 10nA,
+3.0V to +5.5V, Up to 1Mbps, True RS-232
Transceivers (MAX3246E Available in a UCSP
Package)
o For Data Cable Applications:
MAX3380E/MAX3381E: +2.35V to +5.5V, 1A,
2Tx/2Rx RS-232 Transceivers with ±15kV ESD-
Protected I/O and Logic Pins
±15kV ESD-Protected, 1A, 3.0V to 5.5V, 250kbps,
RS-232 Transceivers with AutoShutdown
AutoShutdown and UCSP are trademarks of Maxim Integrated Products, Inc.
Covered by U.S. Patent numbers 4,636,930; 4,679,134; 4,777,577; 4,797,899; 4,809,152; 4,897,774; 4,999,761; 5,649,210; and other patents pending.
Pin Configurations appear at end of data sheet.
Typical Operating Circuits appear at end of data sheet.
*Exposed pad.
+
Denotes a lead(Pb)-free/RoHS-compliant package.
/V
denotes an automotive qualified part.
Ordering Information continued at end of data sheet.
Ordering Information
Selector Guide
PART
NO. OF
DRIVERS/
RECEIVERS
VCC
RANGE
(V)
AutoShutdown
MAX3221E
1/1
+3.0 to +5.5
MAX3223E
2/2
+3.0 to +5.5
MAX3243E
3/5
+3.0 to +5.5
PART
TEMP RANGE
PIN-PACKAGE
MAX3221ECTE+
0°C to +70°C
16 TQFN-EP*
MAX3221ECUE+
0°C to +70°C
16 TSSOP
MAX3221ECAE+
0°C to +70°C
16 SSOP
MAX3221EEAE+
-40°C to +85°C
16 SSOP
MAX3221EETE+
-40°C to +85°C
16 TQFN-EP*
MAX3221EEUE+
-40°C to +85°C
16 TSSOP
MAX3223ECPP+
0°C to +70°C
20 PDIP
MAX3223ECAP+
0°C to +70°C
20 SSOP
MAX3223ECUP+
0°C to +70°C
20 TSSOP
MAX3223ECTP+
0°C to +70°C
20 TQFN-EP*
MAX3223EEPP+
-40°C to +85°C
20 PDIP
MAX3223EEAP+
-40°C to +85°C
20 SSOP
MAX3223EEUP+
-40°C to +85°C
20 TSSOP
MAX3223EETP+
-40°C to +85°C
20 TQFN-EP*
MAX3223EEUP/V+
-40°C to +85°C
20 TSSOP
19-1283; Rev 7; 8/11
MAX3221E/
MAX3223E/MAX3243E