MAXIM MAX3221E, MAX3223E, MAX3243E User Guide

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 data­rate capabilities, and enhanced electrostatic discharge
(ESD) protection. All transmitter outputs and receiver
inputs are protected to ±15kV using IEC 1000-4-2 Air­Gap Discharge, to ±8kV using IEC 1000-4-2 Contact
Discharge, and to ±15kV using the Human Body Model.

The MAX3221E/MAX3223E/MAX3243E achieve a
1µA supply current with Maxim’s revolutionary
AutoShutdown™ feature. They save power without
changes to the existing BIOS or operating system by enter­ing 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 trans­mitter 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 0.1µF capaci­tors for operation from a +3.3V supply. Each device is
guaranteed to run at data rates of 250kbps while main­taining 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 avail­able in space-saving TQFN, SSOP, and TSSOP pack­ages.

Applications

Notebook, Subnotebook, and Palmtop Computers
Cellular Phones
Battery-Powered Equipment
Handheld Equipment
Peripherals
Printers

Next Generation Device Features

♦ 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)

♦ For Data Cable Applications:

MAX3380E/MAX3381E: +2.35V to +5.5V, 1µA,
2Tx/2Rx RS-232 Transceivers with ±15kV ESD­Protected I/O and Logic Pins

MAX3221E/MAX3223E/MAX3243E

†

±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps,

RS-232 Transceivers with AutoShutdown

________________________________________________________________ Maxim Integrated Products 1

19-1283; Rev 6; 9/05

PART

MAX3221ECUE

MAX3221EEAE

-40°C to +85°C

0°C to +70°C

TEMP

RANGE

PIN­PACKAGE

16 TSSOP

16 SSOP

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 paddle.

Ordering Information continued at end of data sheet.

MAX3223EEPP

-40°C to +85°C

20 Plastic DIP

MAX3223EEAP

-40°C to +85°C

20 SSOP

MAX3221EETE

MAX3223ECAP

0°C to +70°C

-40°C to +85°C

16 Thin QFN-EP
(5mm x 5mm)

20 SSOP

Ordering Information

Selector Guide

MAX3223ECUP

0°C to +70°C

20 TSSOP

MAX3223EEUP

-40°C to +85°C

20 TSSOP

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

PKG
CODE

—

—

—

—

—

T1655-2

—

—

MAX3221ECAE

0°C to +70°C

16 SSOP —

MAX3221ECTE

0°C to +70°C

16 Thin QFN-EP
(5mm x 5mm)

T1655-2

MAX3221EEUE

-40°C to +85°C

16 TSSOP —

MAX3223ECPP

0°C to +70°C

20 Plastic DIP —

MAX3223ECTP

0°C to +70°C

20 Thin QFN-EP*
(5mm x 5mm)

T2055-5

MAX3223EETP

-40°C to +85°C

20 Thin QFN-EP*
(5mm x 5mm)

T2055-5

PART

NO. OF

DRIVERS/

VCC

(V)

AutoShutdown

MAX3221E 1/1

✔

MAX3223E 2/2

✔

MAX3243E 3/5

✔

RANGE

RECEIVERS

+3.0 to +5.5

+3.0 to +5.5

+3.0 to +5.5

MAX3221E/MAX3223E/MAX3243E

±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps,
RS-232 Transceivers with AutoShutdown

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VCC= +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.

VCCto GND..............................................................-0.3V to +6V

V+ to GND (Note 1) ..................................................-0.3V to +7V

V- to GND (Note 1) ...................................................+0.3V to -7V

V+ + |V-| (Note 1) .................................................................+13V

Input Voltages

T_IN,

EN, FORCEON, FORCEOFF to GND ............-0.3V to +6V

R_IN to GND ......................................................................±25V

Output Voltages

T_OUT to GND................................................................±13.2V

R_OUT, R2OUTB, INVALID to GND.........-0.3V to (V

CC

+ 0.3V)

Short-Circuit Duration

T_OUT to GND .........................................................Continuous

Continuous Power Dissipation (T

A

= +70°C)

16-Pin SSOP (derate 7.14mW/°C above +70°C) ...........571mW

16-Pin TSSOP (derate 9.4mW/°C above +70°C) ........754.7mW

16-Pin TQFN (derate 20.8mW/°C above +70°C) ......1666.7mW

20-Pin Plastic DIP (derate 11.11mW/°C above +70°C)....889mW

20-Pin SSOP (derate 8.00mW/°C above +70°C) ...........640mW

20-Pin TSSOP (derate 10.9mW/°C above +70°C) .........879mW

20-Pin TQFN (derate 21.3mW/°C above +70°C) ......1702.1mW

28-Pin SSOP (derate 9.52mW/°C above +70°C)............762mW

28-Pin TSSOP (derate 12.8mW/°C above +70°C) .......1026mW

Operating Temperature Ranges

MAX32_ _EC_ _ ....................................................0°C to +70°C

MAX32_ _EE_ _..................................................-40°C to +85°C

Storage Temperature Range .............................-65°C to +160°C

Lead Temperature (soldering, 10s) .................................+300°C

Note 1: V+ and V- can have maximum magnitudes of 7V, but their absolute difference cannot exceed 13V.

VCC= 5.0V

RECEIVER OUTPUTS

AutoShutdown (FORCEON = GND, FORCEOFF = VCC)

LOGIC INPUTS

DC CHARACTERISTICS (VCC= 3.3V or 5.0V, TA= +25°C)

R_OUT receivers disabledOutput Leakage Current ±0.05 ±10 µA

Negative threshold

Positive threshold

Figure 5a

VCC= 3.3V

T_IN, EN, FORCEON,

FORCEOFF

CONDITIONS

I

OUT

= -1.0mA

I

OUT

= 1.6mA

Figure 5a

I

OUT

= -1.0mA

I

OUT

= 1.6mA

T_IN, EN, FORCEON, FORCEOFF

FORCEON = FORCEOFF = VCC,
no load

FORCEOFF = GND, all R_IN = GND

FORCEON = GND,
FORCEOFF = V

CC,

all R_IN open

VCC- 0.6 V

INVALID Output Voltage High

-0.3 0.3 V

Receiver Input Threshold to
INVALID Output Low

0.4 V

INVALID Output Voltage Low

-2.7

V

Receiver Input Threshold to
INVALID Output High

2.7

0.3 1 mA

Supply Current,
AutoShutdown Disabled

1.0 10 µASupply Current, Shutdown

Supply Current, AutoShutdown

2.0

PARAMETER MIN TYP MAX UNITS

Input Logic Threshold Low 0.8 V

1.0 10 µA

Input Logic Threshold High

2.4

V

Output Voltage Low 0.4 V

Output Voltage High VCC- 0.6 VCC- 0.1 V

SYMBOL

Transmitter Input Hysteresis 0.5 V

T_IN, EN, FORCEON, FORCEOFF

Input Leakage Current ±0.01 ±1 µA

kV

MAX3221E/MAX3223E/MAX3243E

±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps,

RS-232 Transceivers with AutoShutdown

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(VCC= +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

PARAMETER MIN TYP MAX UNITS

±25

Output Short-Circuit Current ±60 mA

Output Resistance 300 10M Ω

Output Leakage Current µA

Input Threshold Low

0.6 1.2
V

±5 ±5.4Output Voltage Swing V

CONDITIONS

VCC= V+ = V- = 0, T

OUT

= ±2V

V

OUT

= ±12V, VCC= 0 or 3V to

5.5V, transmitters disabled

All transmitter outputs loaded with
3kΩ to ground

Receiver Positive or Negative
Threshold to INVALID High

1 µsVCC= 5V, Figure 5b

Input Hysteresis 0.5 V

Input Threshold High V

Input Resistance 35 7kΩ

0.8 1.5

1.8 2.4

1.5 2.4

TA= +25°C

TA= +25°C

±5.0Transmitter Output Voltage V

T1IN = T2IN = GND, T3IN = VCC,
T3OUT loaded with 3kΩ to GND,
T1OUT and T2OUT loaded with

2.5mA each

t

INVH

SYMBOL

VCC= 3.3V

VCC= 5.0V

VCC= 3.3V

VCC= 5.0V

±15IEC 1000-4-2 Air-Gap Discharge

Receiver Positive or Negative
Threshold to INVALID Low

30 µsVCC= 5V, Figure 5bt

INVL

Input Voltage Range -25 25 V

Receiver or Transmitter Edge to
Transmitters Enabled

100 µsVCC= 5V, Figure 5bt

WU

Input Voltage Range -25 25 V

±8IEC 1000-4-2 Contact Discharge

R_IN, T_OUT

±15Human Body Model

kV

RECEIVER INPUTS

TRANSMITTER OUTPUTS

MOUSE DRIVEABILITY (MAX3243E)

ESD PROTECTION

Typical Operating Characteristics

(VCC= +3.3V, 250kbps data rate, 0.1µF capacitors, all transmitters loaded with 3kΩ and CL, TA = +25°C, unless otherwise noted.)

-6

-5

-4

-3

-2

-1

0

1

2

3

4

5

6

010002000 3000 4000 5000

MAX3221E/MAX3223E

TRANSMITTER OUTPUT VOLTAGE

vs. LOAD CAPACITANCE

MAX3221E-01

LOAD CAPACITANCE (pF)

TRANSMITTER OUTPUT VOLTAGE (V)

V

OUT+

T1 TRANSMITTING AT 250kbps
T2 (MAX3223E) TRANSMITTING AT 15.6kbps

V

OUT-

0

2

4

6

8

10

12

14

16

0 1000 2000 3000 4000 5000

MAX3221E/MAX3223E

SLEW RATE vs. LOAD CAPACITANCE

MAX3221-TOC2

LOAD CAPACITANCE (pF)

SLEW RATE (V/µs)

-SLEW

+SLEW

FOR DATA RATES UP TO 250kbps

MAX3221E/MAX3223E/MAX3243E

±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps,
RS-232 Transceivers with AutoShutdown

4 _______________________________________________________________________________________

TIMING CHARACTERISTICS—MAX3221E/MAX3223E/MAX3243E

(VCC= +3.0V to +5.5V, C1–C4 = 0.1µF (Note 2), TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

Note 2: C1–C4 = 0.1µF, tested at 3.3V ±10%. C1 = 0.047µF, C2–C4 = 0.33µF, tested at 5.0V ±10%.
Note 3: Transmitter skew is measured at the transmitter zero cross points.

t

PLH

RL= 3kΩ, CL= 1000pF,
one transmitter switching

t

PHL

SYMBOL



t

PHL

- t

PLH





t

PHL

- t

PLH



Receiver Output Disable Time ns

CONDITIONS

µs

0.15

Receiver Propagation Delay

CL= 150pF to
1000pF

kbps

UNITSMIN TYP MAXPARAMETER

(Note 3)

ns50Receiver Skew

ns100Transmitter Skew

VCC= 3.3V,
RL= 3kΩ to 7kΩ,
TA= +25°C,
measured from +3V
to -3V or

-3V to +3V, one
transmitter switching

V/µsTransition-Region Slew Rate 630

CL= 150pF

250

0.15

Maximum Data Rate

nsNormal operationReceiver Output Enable Time

200Normal operation

200

MAX3221E/MAX3223E/MAX3243E

±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps,

RS-232 Transceivers with AutoShutdown

_______________________________________________________________________________________ 5

Typical Operating Characteristics (continued)

(VCC= +3.3V, 250kbps data rate, 0.1µF capacitors, all transmitters loaded with 3kΩ and CL, TA= +25°C, unless otherwise noted.)

-6

-5

-4

-3

-2

-1

0

1

2

3

4

5

6

0

MAX3243E

TRANSMITTER OUTPUT VOLTAGE

vs. LOAD CAPACITANCE

MAX3224E-04

LOAD CAPACITANCE (pF)

TRANSMITTER OUTPUT VOLTAGE (V)

2000 30001000 4000 5000

1 TRANSMITTER AT 250kbps
2 TRANSMITTERS AT 15.6kbps

V

OUT+

V

OUT-

0

4

2

8

6

12

10

14

0 1000 2000 3000 4000 5000

MAX3243E

SLEW RATE vs. LOAD CAPACITANCE

MAX3243E-05

LOAD CAPACITANCE (pF)

SLEW RATE (V/µs)

0

30

20

10

40

50

60

0 20001000 3000 4000 5000

MAX3243E

OPERATING SUPPLY CURRENT

vs. LOAD CAPACITANCE

MAX3243E-06

LOAD CAPACITANCE (pF)

SUPPLY CURRENT (mA)

250kbps

120kbps

20kbps

T1 TRANSMITTING AT 250kbps
T2 (MAX3223E) TRANSMITTING AT 15.6kbps

0

5

10

15

20

25

30

35

40

45

020001000 3000 4000 5000

MAX3221E/MAX3223E

OPERATING SUPPLY CURRENT

vs. LOAD CAPACITANCE

MAX3224E-03

LOAD CAPACITANCE (pF)

SUPPLY CURRENT (mA)

250kbps

120kbps

20kbps

T1 TRANSMITTING AT 250kbps
T2 (MAX3223E) TRANSMITTING AT 15.6kbps

MAX3221E/MAX3223E/MAX3243E

±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps,
RS-232 Transceivers with AutoShutdown

6 _______________________________________________________________________________________

Pin Description

PIN

MAX3221E MAX3223E MAX3243E

TQFN

DIP/

SO/

NAME

FUNCTION

14 1 19 1 — 22 EN

Recei ver E nab l e C ontr ol . D r i ve l ow for nor m al op er ati on.
D r i ve hi g h to for ce the r ecei ver outp uts ( R_O U T) i nto a hi g h-
i m p ed ance state.

16 2 1 2 28 28 C1+

Positive terminal of the voltage doubler Charge-Pump
Capacitor

15 3 20 3 27 27 V+ +5.5V generated by the charge pump

14242423C1-

Negative terminal of the voltage doubler Charge-Pump
Capacitor

25

351

29 C2+ Positive terminal of inverting Charge-Pump Capacitor

36

462

30 C2- Negative terminal of inverting Charge-Pump Capacitor

47

573

31 V- -5.5V generated by the charge pump

58

4-8 1-5 R_IN RS-232 Receiver Inputs

69

13, 14,
15, 17,18R_OUT TTL/CMOS Receiver Outputs

71091121 —

Output of the Valid Signal Detector. INVALID is enabled
high if a valid RS-232 level is present on any receiver
input.

811

12, 13,1410, 11,

12

T_IN TTL/CMOS Transmitter Inputs

912121423—

Drive high to override automatic circuitry keeping
transmitters and charge pump on (FORCEOFF must be
high) (Table 1).

10 13

T_OUT RS-232 Transmitter Outputs

————2019

TTL/CMOS Noninverting Complementary Receiver
Output. Always active.

11 14 16 18 25 24 GND Ground

12 15 17 19 26 26 V

CC

+3.0V to +5.5V Supply Voltage

13 16 18 20 22 —

Force- Off Inp ut, acti ve l ow. D ri ve l ow to shut d ow n tr ansm itters,
r ecei ver s (M AX 3243E, excep t R2OU TB), and on- b oar d char ge
p ump . Thi s overr i d es all autom ati c ci r cui try and FORC E ON
( Tab l e 1) .

—————21SHDN Shutdown Control, Active Low

SSOP/

TSSOP

TQFN

7, 14 9, 16

8, 13 10, 15 15-19

10, 11 12, 13

6, 15 8, 17 9, 10, 11 6, 7, 8

SSOP/

TSSOP

SSOP/

TSSOP

THIN

QFN

INVALID

FORCEON

R2OUTB

FORCEOFF