MAXIM MAX3222E, MAX3232E, MAX3237E, MAX3241E, MAX3246E Technical data

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

General Description

The MAX3222E/MAX3232E/MAX3237E/MAX3241E/
MAX3246E +3.0V-powered EIA/TIA-232 and V.28/V.24
communications interface devices feature low power con­sumption, high data-rate capabilities, and enhanced
electrostatic-discharge (ESD) protection. The enhanced
ESD structure protects all transmitter outputs and
receiver inputs to ±15kV using IEC 1000-4-2 Air-Gap
Discharge, ±8kV using IEC 1000-4-2 Contact Discharge
(±9kV for MAX3246E), and ±15kV using the Human Body
Model. The logic and receiver I/O pins of the MAX3237E
are protected to the above standards, while the transmit­ter output pins are protected to ±15kV using the Human
Body Model.

A proprietary low-dropout transmitter output stage delivers
true RS-232 performance from a +3.0V to +5.5V power
supply, using an internal dual charge pump. The charge
pump requires only four small 0.1µF capacitors for opera­tion from a +3.3V supply. Each device guarantees opera­tion at data rates of 250kbps while maintaining RS-232
output levels. The MAX3237E guarantees operation at
250kbps in the normal operating mode and 1Mbps in the
MegaBaud™ operating mode, while maintaining RS-232­compliant output levels.

The MAX3222E/MAX3232E have two receivers and two
transmitters. The MAX3222E features a 1µA shutdown
mode that reduces power consumption in battery-pow­ered portable systems. The MAX3222E receivers remain
active in shutdown mode, allowing monitoring of external
devices while consuming only 1µA of supply current. The
MAX3222E and MAX3232E are pin, package, and func­tionally compatible with the industry-standard MAX242
and MAX232, respectively.

The MAX3241E/MAX3246E are complete serial ports
(three drivers/five receivers) designed for notebook and
subnotebook computers. The MAX3237E (five drivers/
three receivers) is ideal for peripheral applications that
require fast data transfer. These devices feature a shut­down mode in which all receivers remain active, while
consuming only 1µA (MAX3241E/MAX3246E) or 10nA
(MAX3237E).

The MAX3222E, MAX3232E, and MAX3241E are avail­able in space-saving SO, SSOP, TQFN and TSSOP pack­ages. The MAX3237E is offered in an SSOP package.
The MAX3246E is offered in the ultra-small 6 x 6 UCSP™
package.

Next-Generation Device Features

♦♦

For Space-Constrained Applications

MAX3228E/MAX3229E: ±15kV ESD-Protected,
+2.5V to +5.5V, RS-232 Transceivers in UCSP

♦♦

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

Applications

Battery-Powered Equipment

Cell Phones Smart Phones

Cell-Phone Data Cables

Notebook, Subnotebook, and Palmtop Computers

Printers

xDSL Modems

MAX3222E/MAX3232E/MAX3237E/MAX3241E /MAX3246E

±15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,

Up to 1Mbps, True RS-232 Transceivers

________________________________________________________________

Maxim Integrated Products

1

19-1298; Rev 12; 12/10

Ordering Information

Ordering Information continued at end of data sheet.

+

Denotes a lead(Pb)-free/RoHS-compliant package.

*

Dice are tested at TA= +25°C, DC parameters only.

**

EP = Exposed pad.

/V denotes an automotive qualified part.

Pin Configurations, Selector Guide, and Typical Operating
Circuits appear at end of data sheet.

MegaBaud and UCSP are trademarks of Maxim Integrated
Products, Inc.

PART TEMP RANGE PIN-PACKAGE

MAX3222ECTP+ 0°C to +70°C

MAX3222ECUP+ 0°C to +70°C 20 TSSOP

MAX3222ECAP+ 0°C to +70°C 20 SSOP

MAX3222ECWN+ 0°C to +70°C 18 Wide SO

MAX3222ECPN+ 0°C to +70°C 18 Plast ic DIP

MAX3222EC/D+ 0°C to +70°C Dice*

MAX3222EETP+ -40°C to +85°C

MAX3222EEUP/V+ -40°C to +85°C 20 TSSOP

MAX3222EEUP+ -40°C to +85°C 20 TSSOP

MAX3222EEAP+ -40°C to +85°C 20 SSOP

MAX3222EEWN+ -40°C to +85°C 18 Wide SO

MAX3222EEPN+ -40°C to +85°C 18 Plast ic DIP

MAX3232ECAE+ 0°C to +70°C 16 SSOP

MAX3232ECWE+ 0°C to +70°C 16 Wide SO

MAX3232ECPE+ 0°C to +70°C 16 Plastic DIP

20 TQFN-EP**
(5mm x 5mm)

20 TQFN-EP**
(5mm x 5mm)

MAX3222E/MAX3232E/MAX3237E/MAX3241E /MAX3246E

±15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VCC= +3V to +5.5V, C1–C4 = 0.1µF, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.) (Notes 3, 4)

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, SHDN, MBAUD to GND ........................-0.3V to +6V

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

Output Voltages

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

R_OUT, R_OUTB (MAX3237E/MAX3241E)...-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

16-Pin Wide SO (derate 9.52mW/°C above +70°C) .....762mW

18-Pin Wide SO (derate 9.52mW/°C above +70°C) .....762mW

18-Pin PDIP (derate 11.11mW/°C above +70°C)..........889mW

20-Pin TQFN (derate 21.3mW/°C above +70°C) ........1702mW

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

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

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

28-Pin Wide SO (derate 12.50mW/°C above +70°C) .............1W

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

32-Pin TQFN (derate 33.3mW/°C above +70°C)...........2666mW

6 x 6 UCSP (derate 12.6mW/°C above +70°C) .............1010mW

Operating Temperature Ranges

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

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

Storage Temperature Range .............................-65°C to +150°C

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

Soldering Temperature (reflow) .......................................+260°C

Bump Reflow Temperature (Note 2)

Infrared, 15s..................................................................+200°C

Vapor Phase, 20s..........................................................+215°C

Note 1: V+ and V- can have maximum magnitudes of 7V, but their absolute difference cannot exceed 13V.
Note 2: This device is constructed using a unique set of packaging techniques that impose a limit on the thermal profile the device

can be exposed to during board-level solder attach and rework. This limit permits only the use of the solder profiles recom­mended in the industry-standard specification, JEDEC 020A, paragraph 7.6, Table 3 for IR/VPR and convection reflow.
Preheating is required. Hand or wave soldering is not allowed.

DC CHARACTERISTICS (VCC = +3.3V or +5V, TA = +25°C)

Supply Current SHDN = VCC, no load

Shutdown Supply Current

LOGI C I N PUT S

Input Logic Low T_IN, EN, SHDN, MBAUD 0.8 V

Input Logic High T_IN, EN, SHDN, MBAUD

Transm itter Input Hysteresis 0.5 V

Input Leakage Current

PARAMETER CONDITIONS MIN TYP MAX UNITS

SHDN = GND 1 10 μA
SHDN = R_IN = GND, T_IN = GND or V

T_IN, EN, SHDN

T_IN, SHDN, MBAUD MAX3237E (Note 5) 9 18

MAX3222E, MAX3232E,
MAX3241E, MAX3246E

MAX3237E 0.5 2.0

(MAX3237E) 10 300 nA

CC

VCC = +3.3V 2.0

= +5.0V 2.4

V

CC

MAX3222E, MAX3232E,
MAX3241E, MAX3246E

0.3 1

±0.01 ±1

mA

V

μA

MAX3222E/MAX3232E/MAX3237E/MAX3241E /MAX3246E

±15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,

Up to 1Mbps, True RS-232 Transceivers

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(VCC= +3V to +5.5V, C1–C4 = 0.1µF, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.) (Notes 3, 4)

PARAMETER CONDITIONS MIN TYP MAX UNITS

RECEIVER OUTPUTS

Output Leakage Current

Output-Voltage Low

Output-Voltage High I

RECEIVER INPUTS

Input Voltage Range -25 +25 V

Input Threshold Low TA = +25°C

Input Threshold High TA = +25°C

Input Hysteresis 0.5 V

Input Resistance TA = +25°C 3 5 7 k

TRANSMITTER OUTPUTS

Output Voltage Swing

Output Resistance VCC = 0V, transmitter output = ±2V 300 50k 

Output Short-Circuit Current ±60 mA

Output Leakage Current

MOUSE DRIVABILITY (MAX3241E)

Transm itter Output Voltage

ESD PROTECTION

R_IN, T_OUT

T_IN, R_IN, R_OUT, EN, SHDN,
MBAUD

R_OUT (MAX3222E/MAX3237E/MAX3241E/
MAX3246E), EN = V

I

OUT

MAX3246E), I

OUT

All transm itter output s loaded with 3 k to ground
(Note 6)

V

CC

disabled (MAX3222E/MAX3232E/MAX3241E/MAX3246E)

T1IN = T2IN = GND, T3IN = V
3k to GND, T1OUT and T2OUT loaded with 2.5mA
each

Human Body Model ±15

IEC 1000-4-2 Air-Gap Discharge (except MAX3237E) ±15

IEC 1000-4-2 Contact Discharge (except MAX3237E) ±8

IEC 1000-4-2 Contact Discharge (MAX3246E on ly) ±9

MAX3237E

= 1.6mA (MAX3222E/MAX3232E/MAX3241E/

= -1.0mA

= 0V or +3.0V to +5.5V, V

, receivers disab led

CC

= 1.0mA (MAX3237E)

OUT

VCC = +3.3V 0.6 1.1

= +5.0V 0.8 1.5

V

CC

VCC = +3.3V 1.5 2.4

= +5.0V 2.0 2.4

V

CC

= ±12V, transmitters

OUT

, T3OUT loaded with

CC

Human Body Model ±15

IEC 1000-4-2 Air-Gap Discharge ±15

IEC 1000-4-2 Contact Discharge ±8

±0.05 ±10 μA

0.4 V

V

-

CC

0.6

±5 ±5.4 V

±5 V

VCC -

0.1

±25 μA

V

V

V

kV

kV

MAX3222E/MAX3232E/MAX3237E/MAX3241E /MAX3246E

±15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers

4 _______________________________________________________________________________________

TIMING CHARACTERISTICS—MAX3237E

(VCC= +3V to +5.5V, C1–C4 = 0.1µF, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.) (Note 3)

Note 3: MAX3222E/MAX3232E/MAX3241E: C1–C4 = 0.1µF tested at +3.3V ±10%; C1 = 0.047µF, C2, C3, C4 = 0.33µF tested at +5.0V

±10%. MAX3237E: C1–C4 = 0.1µF tested at +3.3V ±5%, C1–C4 = 0.22µF tested at +3.3V ±10%; C1 = 0.047µF, C2, C3, C4 =

0.33µF tested at +5.0V ±10%. MAX3246E: C1-C4 = 0.22µF tested at +3.3V ±10%; C1 = 0.22µF, C2, C3, C4 = 0.54µF tested at
+5.0V ±10%.

Note 4: MAX3246E devices are production tested at +25°C. All limits are guaranteed by design over the operating temperature range.
Note 5: The MAX3237E logic inputs have an active positive feedback resistor. The input current goes to zero when the inputs are at

the supply rails.

Note 6: MAX3241EEUI is specified at T

A

= +25°C.

Note 7: Transmitter skew is measured at the transmitter zero crosspoints.

TIMING CHARACTERISTICS—MAX3222E/MAX3232E/MAX3241E/MAX3246E

(VCC= +3V to +5.5V, C1–C4 = 0.1µF, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.) (Notes 3, 4)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Maximum Data Rate

Receiver Propagation Delay

Receiver Output Enable Time Normal operation (except MAX3232E) 200 ns

Receiver Output Disable Time Normal operation (except MAX3232E) 200 ns

Transmitter Skew |t

Receiver Skew |t

PHL

PHL

Transition-Region Slew Rate

Receiver Propagation Delay R_IN to R_OUT, CL = 150pF

Receiver Output Enable Time Normal operation 2.6 µs

Receiver Output Disable Time Normal operation 2.4 µs

Transmitter Skew (Note 7)

Receiver Skew |t

PARAMETER CONDITIONS MIN TYP MAX UNITS

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

VCC = +3.0V to +4.5V, RL = 3kΩ, CL = 250pF,
one transmitter switching, MBAUD = V

V

CC

one transmitter switching, MBAUD = V

|t

PHL

|t

PHL

PHL

= 3kΩ,

R

L

C

= 1000pF,

L

one transmitter
switching T

TA = T
(MAX3222E/MAX3232E/
MAX3241E) (Note 6)

A

Receiver input to receiver output,

= 150pF

C

L

to T

MIN

MAX

250

= + 25°C ( M AX 3246E ) 250

0.15

0.15

kbps

µs

| (Note 7) 100 ns

|50ns

= + 3.3V , TA = + 25°C ,

V

C C

R

= 3kΩ to 7kΩ , m easur ed

L

fr om + 3.0V to - 3.0V or - 3.0V to

C

= 150pF

L

to 1000pF

6 30 V/µs

t

t

PHL

PLH

- t

- t

PLH

PLH

+ 3.0V , one tr ansm i tter sw i tchi ng

250

CC

= +4.5V to +5.5V, RL = 3kΩ, CL = 1000pF,

CC

t

PHL

t

PLH

- t

|, MBAUD = GND

PLH

- t

|, MBAUD = V

PLH

- t

|50ns

PLH

CC

1000Maximum Data Rate

1000

0.15

0.15

100 ns

kbps

µs

Transition-Region Slew Rate

VCC = +3.3V,
R

= 3kΩ to 7kΩ,

L

+3.0V to -3.0V or

-3.0V to +3.0V,
= +25°C

T

A

CL = 150pF
to 1000pF

C

= 150pF to 2500pF,

L

MBAUD = GND

MBAUD = GND 6 30

MBAUD = V

CC

24 150

430

V/µs

MAX3222E/MAX3232E/MAX3237E/MAX3241E /MAX3246E

±15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,

Up to 1Mbps, True RS-232 Transceivers

_______________________________________________________________________________________

5

__________________________________________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.)

MAX3222E/MAX3232E

TRANSMITTER OUTPUT VOLTAGE

vs. LOAD CAPACITANCE

6
5
4
3

T1 TRANSMITTING AT 250kbps

2

T2 TRANSMITTING AT 15.6kbps

1
0

-1

-2

-3

-4

TRANSMITTER OUTPUT VOLTAGE (V)

-5

-6
0 1000 2000 3000 4000 5000

LOAD CAPACITANCE (pF)

V

OUT+

16

14

MAX3237E toc01

12

10

8

6

SLEW RATE (V/μs)

4

V

OUT-

2

0

MAX3222E/MAX3232E

SLEW RATE vs. LOAD CAPACITANCE

-SLEW

+SLEW

FOR DATA RATES UP TO 250kbps

0 1000 2000 3000 4000 5000

LOAD CAPACITANCE (pF)

45

40

MAX3237E toc02

35

30

25

20

15

SUPPLY CURRENT (mA)

10

5

0

MAX3241E

TRANSMITTER OUTPUT VOLTAGE

vs. LOAD CAPACITANCE

6
5
4
3

1 TRANSMITTER AT 250kbps

2

2 TRANSMITTERS AT 15.6kbps

1
0

-1

-2

-3

-4

TRANSMITTER OUTPUT VOLTAGE (V)

-5

-6

0 1000 2000 3000 4000 5000

LOAD CAPACITANCE (pF)

MAX3237E

TRANSMITTER OUTPUT VOLTAGE

vs. LOAD CAPACITANCE (MBAUD = GND)

6
5
4

FOR DATA RATES UP TO 250kbps

3

1 TRANSMITTER AT 250kbps

2

4 TRANSMITTERS AT 15.6kbps
ALL TRANSMITTERS LOADED

1

WITH 3kΩ + C

0

-1

-2

-3

-4

TRANSMITTER OUTPUT VOLTAGE (V)

-5

-6
0

L

1000 1500500 2000 2500 3000

LOAD CAPACITANCE (pF)

SLEW RATE vs. LOAD CAPACITANCE

14

V

OUT+

V

OUT-

MAX3237E to04

12

10

8

6

SLEW RATE (V/μs)

4

2

0

0 1000 2000 3000 4000 5000

TRANSMITTER OUTPUT VOLTAGE

6

V

V

OUT+

OUT-

MAX3237E toc07

5
4
3
2
1
0

-1

-2

-3

-4

TRANSMITTER OUTPUT VOLTAGE (V)

-5

-6
0 1000 1500500 2000 2500 3000

MAX3241E

LOAD CAPACITANCE (pF)

MAX3237E

vs. LOAD CAPACITANCE

FOR DATA RATES UP TO 250kbps
1 TRANSMITTER 250kbps
4 TRANSMITTERS 15.6kbps
ALL TRANSMITTERS LOADED
WITH 3kΩ + C

L

LOAD CAPACITANCE (pF)

60

50

MAX3237E toc05

40

30

20

SUPPLY CURRENT (mA)

10

0

7.5

V

+

OUT

V

OUT-

5.0

MAX3246E toc07A

2.5

0

-2.5

-5.0

TRANSMITTER OUTPUT VOLTAGE (V)

-7.5

MAX3222E/MAX3232E

OPERATING SUPPLY CURRENT

vs. LOAD CAPACITANCE

T1 TRANSMITTING AT 250kbps
T2 TRANSMITTING AT 15.6kbps

250kbps

120kbps

20kbps

0 20001000 3000 4000 5000

LOAD CAPACITANCE (pF)

MAX3241E

OPERATING SUPPLY CURRENT

vs. LOAD CAPACITANCE

1 TRANSMITTER AT 250kbps
2 TRANSMITTERS AT 15.6kbps

250kbps

120kbps

20kbps

0 20001000 3000 4000 5000

LOAD CAPACITANCE (pF)

MAX3237E

TRANSMITTER OUTPUT VOLTAGE

vs. LOAD CAPACITANCE (MBAUD = V

2Mbps

1 TRANSMITTER AT FULL DATA RATE
4 TRANSMITTERS AT 1/16 DATA RATE

LOAD, EACH OUTPUT

3kΩ + C

L

2Mbps

0

500 1000 1500 2000

LOAD CAPACITANCE (pF)

CC

1Mbps

1.5Mbps

1.5Mbps

1Mbps

)

MAX3237E toc03

MAX3237E toc06

MAX3237E toc08

MAX3222E/MAX3232E/MAX3237E/MAX3241E /MAX3246E

±15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers

6 _______________________________________________________________________________________

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.)

SLEW RATE vs. LOAD CAPACITANCE

12

10

8

6

SLEW RATE (V/μs)

4

1 TRANSMITTER AT 250kbps
4 TRANSMITTERS AT 15.6kbps

2

ALL TRANSMITTERS LOADED
WITH 3kΩ + C

0

0

TRANSMITTER SKEW vs. LOAD CAPACITANCE

100

80

60

40

|t

- t

PLH

TRANSMITTER SKEW (ns)

1 TRANSMITTER AT 500kbps

20

4 TRANSMITTERS AT 1/16 DATA RATE
ALL TRANSMITTERS LOADED
WITH 3kΩ + C

0

0

TRANSMITTER OUTPUT VOLTAGE

7
6
5
4

1 TRANSMITTER AT 250kbps

3

2 TRANSMITTERS AT 15.6kbps

2
1
0

-1

-2

-3

TRANSMITTER OUTPUT VOLTAGE (V)

-4

-5

-6
0 5000

MAX3237E

(MBAUD = GND)

SR-

SR+

L

1000 1500500 2000 2500 3000

LOAD CAPACITANCE (pF)

MAX3237E

(MBAUD = V

|

PHL

L

1000 1500500 2000

LOAD CAPACITANCE (pF)

)

CC

MAX3246E

vs. LOAD CAPACITANCE

V

OUT+

V

OUT-

LOAD CAPACITANCE (pF)

MAX3237E

SUPPLY CURRENT vs. LOAD CAPACITANCE

WHEN TRANSMITTING DATA (MBAUD = GND)

50

40

30

20

SUPPLY CURRENT (mA)

1 TRANSMITTER AT 20kbps, 120kbps, 250kbps
4 TRANSMITTERS AT 15.6kbps

10

ALL TRANSMITTERS LOADED
WITH 3kΩ + C

0

0

MAX3237E toc09

SLEW RATE vs. LOAD CAPACITANCE

(MBAUD = V

70

60

50

40

30

SLEW RATE (V/μs)

20

1 TRANSMITTER AT FULL DATA RATE
4 TRANSMITTERS AT 1/16 DATA RATE

10

3kΩ + C

L

0

500 1000 1500 2000

0

-SLEW, 1Mbps

LOAD EACH OUTPUT

LOAD CAPACITANCE (pF)

)

CC

+SLEW, 1Mbps

-SLEW, 2Mbps
+SLEW, 2Mbps

MAX3237E toc10

MAX3237E

TRANSMITTER OUTPUT VOLTAGE

vs. SUPPLY VOLTAGE (MBAUD = GND)

6

MAX3237E toc12

5
4
3
2
1
0

-1

-2

-3

-4

TRANSMITTER OUTPUT VOLTAGE (V)

-5

-6

2.0 3.0 3.52.5 4.0 4.5 5.0

1 TRANSMITTER AT 250kbps
4 TRANSMITTERS AT 15.6kbps
ALL TRANSMITTERS LOADED
WITH 3kΩ + 1000pF

SUPPLY VOLTAGE (V)

V

+

OUT

V

MAX3237E toc13

OUT-

vs. SUPPLY VOLTAGE (MBAUD = GND)

50

40

30

20

1 TRANSMITTER AT 250kbps

SUPPLY CURRENT (mA)

4 TRANSMITTERS AT 15.6kbps

10

ALL TRANSMITTERS LOADED
WITH 3kΩ AND 1000pF

0

2.0

MAX3246E

SLEW RATE vs. LOAD CAPACITANCE

16

MAX3237E toc15

400030001000 2000

14

12

10

SLEW RATE (V/μs)

8

6

4

0

SR-

SR+

2000 30001000 4000 5000

LOAD CAPACITANCE (pF)

MAX3237E toc16

60

1 TRANSMITTER AT 250kbps

55

2 TRANSMITTERS AT 15.6kbps

50
45
40
35
30
25
20

SUPPLY CURRENT (mA)

15

10

5
0

0

MAX3237E

250kbps

L

1000 1500500 2000 2500 3000

LOAD CAPACITANCE (pF)

MAX3237E SUPPLY CURRENT

3.0 3.52.5 4.0 4.5 5.0

SUPPLY VOLTAGE (V)

MAX3246E

OPERATING SUPPLY CURRENT

vs. LOAD CAPACITANCE

250kbps

120kbps

20kbps

1000 2000 3000 4000 5000

LOAD CAPACITANCE (pF)

120kbps

20kbps

MAX3237E toc11

MAX3237E toc14

MAX3237E toc17

MAX3222E/MAX3232E/MAX3237E/MAX3241E /MAX3246E

±15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,

Up to 1Mbps, True RS-232 Transceivers

_______________________________________________________________________________________ 7

*

These pins have an active positive feedback resistor internal to the MAX3237E, allowing unused inputs to be left unconnected.

Pin Description

PIN

MAX3222E MAX3232E MAX3241E

SO/

TQFN

19 1 1 — — — 13* 23 22 B3 EN

1 2 2 16 1 2 28 28 28 F3 C1+

20 3 3 15 2 3 27 27 27 F1 V+

2 4 4 1 3 4 25 24 23 F4 C1-

3 5 5 2 4 5 1 1 29 E1 C2+

4 6 6 3 5 6 3 2 30 D1 C2-

DIP

TSSOP/

SSOP

TQFN

SO/DIP/

SSOP/
16-PIN

TSSOP

20-PIN

TSSOP

MAX3237E SSOP/

SO/

TSSOP

TQFN

MAX3246E

NAME FUNCTION

Receiver Enable. Active
low.

Positive Terminal of
Voltage-Doubler Charge­Pump Capacitor

+5.5V Generated by the
Charge Pump

Negative Terminal of
Voltage-Doubler Charge­Pump Capacitor

Positive Terminal of
Inverting Charge-Pump
Capacitor

Negative Terminal of
Inverting Charge-Pump
Capacitor

5 7 7 4 6 7 4 3 31 C1 V-

9,

6, 15

7, 14

8, 13

10, 11

8,

8, 17

15

9,

9, 16

14

10,

10, 15

13

11,

12, 13 8, 9 10, 11

12

5,

7, 14 8, 17

12

6,

8, 13 9, 16 8, 9, 11 4–8 1–5

11

10

7,

9, 12

12,

15

13,

14

5, 6, 7,

10, 12

18, 20,

21

17*, 19*,
22*, 23*,

24*

10,

11

15–19

12,
13,

14

6,
7,

8

13,
14,
15,

17, 18

10,
11,

12

F6, E6,

D6

A4, A5,
A6, B6,

C6

C2, B1,
A1, A2,

A3

E3, E2,

D2

T_OUT

R_IN

R_OUT

T_IN

-5.5V Generated by the
Charge Pump

RS-232 Transmitter
Outputs

RS-232 Receiver Inputs

TTL/CMOS Receiver
Outputs

TTL/CMOS Transmitter
Inputs