MAX3225ECAP+T - Maxim Integrated

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 MAX3224E/MAX3225E/MAX3226E/MAX3227E/

MAX3244E/MAX3245E are 3V-powered EIA/TIA-232

and V.28/V.24 communications interfaces with automat-

ic shutdown/wakeup features, high data-rate capabili-

ties, and enhanced electrostatic discharge (ESD)

protection. All transmitter outputs and receiver inputs

are protected to ±15kV using IEC 1000-4-2 Air-Gap

Discharge, ±8kV using IEC 1000-4-2 Contact Discharge,

and ±15kV using the Human Body Model.

All devices achieve a 1µA supply current using Maxim’s

revolutionary AutoShutdown Plus™ feature. These

devices automatically enter a low-power shutdown

mode when the RS-232 cable is disconnected or the

transmitters of the connected peripherals are inactive,

and the UART driving the transmitter inputs is inactive

for more than 30 seconds. They turn on again when

they sense a valid transition at any transmitter or receiv-

er input. AutoShutdown Plus saves power without

changes to the existing BIOS or operating system.

The MAX3225E/MAX3227E/MAX3245E also feature

MegaBaud™ operation, guaranteeing 1Mbps for high-

speed applications such as communicating with ISDN

modems. The MAX3224E/MAX3226E/MAX3244E guar-

antee 250kbps operation. The transceivers have a pro-

prietary low-dropout transmitter output stage enabling

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. The MAX3224E–MAX3227E feature a logic-

level output (READY) that asserts when the charge

pump is regulating and the device is ready to begin

transmitting.

All devices are available in a space-saving TQFN,

SSOP, and TSSOP (MAX3224E/MAX3225E/MAX3244E/

MAX3245E) packages.

________________________Applications

Notebook, Subnotebook, and Palmtop Computers

Cellular Phones

Battery-Powered Equipment

Hand-Held 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/MAX3241E/MAX3246E:

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

+5.5V, Up to 1Mbps, True RS-232 Transceivers

(MAX3246E Available 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

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

RS-232 Transceivers with AutoShutdown Plus

19-1339; Rev 10; 3/11

PART

MAX3224E

MAX3225E

MAX3226E

1/1

2/2

NO. OF

DRIVERS/

RECEIVERS

READY

OUTPUT

✔

Auto-

Shutdown

Plus

✔

250k

GUARANTEED

DATA RATE

(bps)

MAX3227E

MAX3244E

MAX3245E

3/5

1/1 ✔

—

✔

250k

Ordering Information continued at end of data sheet.

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

EP = Exposed pad.

AutoShutdown Plus, MegaBaud, and UCSP are trademarks of

Maxim Integrated Products, Inc.

_____________________ Selector Guide

Ordering Information

PART TEMP RANGE PIN-PACKAGE

MAX3224ECTP+ 0°C to +70°C 20 TQFN-EP*

MAX3224ECUP+ 0°C to +70°C 20 TSSOP

MAX3224ECAP+ 0°C to +70°C 20 SSOP

MAX3224ECPP+ 0°C to +70°C 20 Plastic DIP

MAX3224EETP+ -40°C to +85°C 20 TQFN-EP*

MAX3224EEUP+ -40°C to +85°C 20 TSSOP

MAX3224EEAP+ -40°C to +85°C 20 SSOP

MAX3224EEPP+ -40°C to +85°C 20 Plastic DIP

MAX3224EAAP+ -40°C to +125°C 20 SSOP

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/

MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VCC = +3V to +5.5V, C1–C4 = 0.1µF, tested at 3.3V ±10%; C1= 0.047µF, C2–C4 = 0.33µF, tested at 5.0V ±10%; TA= TMIN to TMAX,

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.

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

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

Output Voltages

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

R_OUT, INVALID, READY to GND .........-0.3V to (VCC + 0.3V)

Short-Circuit Duration

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

Continuous Power Dissipation (TA= +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 TQFN (derate 21.3mW/°C above +70°C) ....1702.1mW

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

28-Pin Wide SO (derate 12.5mW/°C above +70°C)............1W

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

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

36-Pin TQFN (derate 26.3mW/°C above +70°C)...........2105mW

Operating Temperature Ranges

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

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

MAX32_ _EAA_..............................................-40°C to +125°C

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

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

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

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

VCC = 5.0V

FORCEON = GND, FORCEOFF = VCC,

all R_IN idle, all T_IN idle

TA= +25°C

VCC = 3.3V

T_IN, FORCEON,

FORCEOFF

CONDITIONS

kΩ357Input Resistance

V0.5Input Hysteresis

1.8 2.4 V

1.5 2.4

Input Threshold High

0.8 1.5 V

0.6 1.2

Input Threshold Low

V-25 +25Input Voltage Range

VCC - 0.6 VCC - 0.1

Output Voltage High

V0.4Output Voltage Low

µA110Supply Current, Shutdown

µA110

Supply Current,

AutoShutdown Plus

µA±0.05 ±10Output Leakage Current

µA±0.01 ±1

Transmitter Input Hysteresis V0.5

2.4

Input Logic Threshold High

mA0.3 1

Supply Current,

AutoShutdown Plus Disabled

V0.8Input Logic Threshold Low

UNITSMIN TYP MAXSYMBOLPARAMETER

FORCEOFF = GND

TA= +25°C

VCC = 5.0V

VCC = 3.3V

TA= +25°C

R_OUT (MAX3244E/MAX3245E), receivers

disabled

T_IN, FORCEON, FORCEOFF

VCC = 5.0V

FORCEON = FORCEOFF = VCC, no load

T_IN, FORCEON, FORCEOFF

IOUT = -1.0mA

VCC = 3.3V

IOUT = 1.6mA

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

LOGIC INPUTS AND RECEIVER OUTPUTS

RECEIVER INPUTS

Input Leakage Current

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

ELECTRICAL CHARACTERISTICS (continued)

(VCC = +3V to +5.5V, C1–C4 = 0.1µF, tested at 3.3V ±10%; C1= 0.047µF, C2–C4 = 0.33µF, tested at 5.0V ±10%; TA= TMIN to TMAX,

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

CONDITIONS

Ω300 10MOutput Resistance

V±5 ±5.4Output Voltage Swing

UNITSMIN TYP MAXSYMBOLPARAMETER

Figure 4a

T1IN = T2IN = GND, T3IN = VCC,

T3OUT loaded with 3kΩto GND,

T1OUT and T2OUT loaded with

2.5mA each

s15 30 60t

AUTOSHDN

Receiver or Transmitter Edge to

Transmitters Shutdown

µs100tWU

Receiver or Transmitter Edge to

Transmitters Enabled

µs30tINVL

Receiver Positive or Negative

Threshold to INVALID Low

µs1tINVH

Receiver Positive or Negative

Threshold to INVALID High

VCC - 0.6

INVALID, READY

Output Voltage High

(MAX3224E–MAX3227E)

V0.4

INVALID, READY

Output Voltage Low

(MAX3224E–MAX3227E)

V-0.3 +0.3

Receiver Input Threshold to

INVALID Output Low

-2.7 V

2.7

Receiver Input Threshold to

INVALID Output High

±15

±8R_IN, T_OUT kV

±15

V±5Transmitter Output Voltage

µA±25Output Leakage Current

±60 mAOutput Short-Circuit Current

VCC = V+ = V- = 0V, transmitter outputs = ±2V

All transmitter outputs loaded with 3kΩto

ground

VCC = 5V, Figure 5b (Note 2)

VCC = 5V, Figure 4b

IOUT = -1.0mA

IOUT = -1.6mA

Figure 4a

Negative threshold

Positive threshold

Human Body Model

VCC = 0V or 3V to 5.5V, VOUT = ±12V,

Transmitters disabled

IEC 1000-4-2 Contact Discharge

IEC 1000-4-2 Air Discharge

TRANSMITTER OUTPUTS

MOUSE DRIVEABILITY (MAX3244E/MAX3245E)

ESD PROTECTION

AutoShutdown Plus (FORCEON = GND, FORCEOFF = VCC)

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

TIMING CHARACTERISTICS—MAX3224E/MAX3226E/MAX3244E

(VCC = +3V to +5.5V, C1–C4 = 0.1µF, tested at 3.3V ±10%; C1= 0.047µF, C2–C4 = 0.33µF, tested at 5.0V ±10%; TA= TMIN to TMAX,

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

TIMING CHARACTERISTICS—MAX3225E/MAX3227E/MAX3245E

(VCC = +3V to +5.5V, C1–C4 = 0.1µF, tested at 3.3V ±10%; C1= 0.047µF, C2–C4 = 0.33µF, tested at 5.0V ±10%; TA= TMIN to TMAX,

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

Note 2: A transmitter/receiver edge is defined as a transition through the transmitter/receiver input logic thresholds.

Note 3: Transmitter skew is measured at the transmitter zero cross points.

CL= 150pF

to 1000pF

R_IN to R_OUT, CL= 150pF

RL= 3kΩ, CL= 1000pF,

one transmitter switching

VCC = 3.3V, TA= +25°C,

RL= 3kΩto 7kΩ,

measured from +3V to -3V

or -3V to +3V, one trans-

mitter switching

Normal operation (MAX3244E only)

(Note 3)

CONDITIONS

0.15tPLH

µs

0.15tPHL

kbps250Maximum Data Rate

Receiver Propagation Delay

V/µs630Transition-Region Slew Rate

ns200Receiver Output Enable Time

ns200Receiver Output Disable Time

ns100

⏐tPHL - tPLH ⏐

Transmitter Skew

ns50

⏐tPHL - tPLH ⏐

Receiver Skew

UNITSMIN TYP MAXSYMBOLPARAMETER

VCC = 4.5V to 5.5V, RL= 3kΩ,

CL= 1000pF, one transmitter switching

VCC = 3.0V to 4.5V, RL= 3kΩ,

CL= 250pF, one transmitter switching

RL= 3kΩ, CL= 1000pF,

one transmitter switching

VCC = 3.3V, TA= +25°C,

RL= 3kΩto 7kΩ, CL= 150pF to 1000pF,

measured from +3V to -3V or -3V to +3V,

one transmitter switching

(Note 3)

R_IN to R_OUT, CL= 150pF

Normal operation (MAX3245E only)

CONDITIONS

1000

1000 kbps

250

Maximum Data Rate

V/µs24 150Transition-Region Slew Rate

ns50

⏐tPHL - tPLH ⏐

Receiver Skew

ns25

⏐tPHL - tPLH ⏐

Transmitter Skew

µs

0.15tPHL

Receiver Propagation Delay 0.15tPLH

ns200Receiver Output Enable Time

ns200Receiver Output Disable Time

UNITSMIN TYP MAXSYMBOLPARAMETER

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

__________________________________________Typical Operating Characteristics

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

-6

-5

-4

-3

-2

-1

0 1000 2000 3000 4000 5000

MAX3224E/MAX3226E

TRANSMITTER OUTPUT VOLTAGE

vs. LOAD CAPACITANCE

MAX3224-7/44/45E-01

LOAD CAPACITANCE (pF)

TRANSMITTER OUTPUT VOLTAGE (V)

T1 TRANSMITTING AT 250kbps

T2 (MAX3224E) TRANSMITTING AT 15.6kbps

VOUT+

VOUT-

0 1000 2000 3000 4000 5000

MAX3224E/MAX3226E

SLEW RATE vs. LOAD CAPACITANCE

MAX3224-7/44/45E-02

LOAD CAPACITANCE (pF)

SLEW RATE (V/μs)

-SLEW

+SLEW

FOR DATA RATES UP TO 250kbps

0 20001000 3000 4000 5000

MAX3224E/MAX3226E

OPERATING SUPPLY CURRENT

vs. LOAD CAPACITANCE

MAX3224-7/44/45E-03

LOAD CAPACITANCE (pF)

SUPPLY CURRENT (mA)

250kbps

120kbps

20kbps

T1 TRANSMITTING AT 250kbps

T2 (MAX3224E) TRANSMITTING AT 15.6kbps

-7.5

-2.5

-5.0

2.5

5.0

7.5

0 1000500 1500 2000 2500

MAX3225E/MAX3227E

TRANSMITTER OUTPUT VOLTAGE

vs. LOAD CAPACITANCE

MAX3224-7/44/45E-04

LOAD CAPACITANCE (pF)

TRANSMITTER OUTPUT VOLTAGE (V)

2Mbps

1.5Mbps

1Mbps

1 TRANSMITTER AT FULL DATA RATE

1 TRANSMITTER AT 1/16 DATA RATE

(MAX3225E)

LOAD = 3kΩ + CL

0 1000500 1500 2000 2500 3000

MAX3225E/MAX3227E

TRANSMITTER SKEW

vs. LOAD CAPACITANCE

MAX3224-7/44/45E-07

LOAD CAPACITANCE (pF)

TRANSMITTER SKEW (ns)

AVERAGE: 10 PARTS

1 TRANSMITTER AT 512kbps

1 TRANSMITTER AT 30kbps

(MAX3225E)

LOAD = 3kΩ + CL

0 500 1000 1500 2000 2500

MAX3225E/MAX3227E

SLEW RATE vs. LOAD CAPACITANCE

MAX3224-7/44/45E-05

LOAD CAPACITANCE (pF)

SLEW RATE (V/μs)

1 TRANSMITTER AT 1Mbps

1 TRANSMITTER AT 62.5kbps (MAX3225E)

-SLEW

+SLEW

100

0 500 1000 1500 2000 2500

MAX3225E/MAX3227E

OPERATING SUPPLY CURRENT

vs. LOAD CAPACITANCE

MAX3224-7/44/45E-06

LOAD CAPACITANCE (pF)

SUPPLY CURRENT (mA)

2Mbps

1.5Mbps

1Mbps

1 TRANSMITTER AT FULL DATA RATE

1 TRANSMITTER AT 1/16 DATA RATE

(MAX3225E)

LOAD = 3kΩ + CL

-40 0 20-20 40 60 80 100

MAX3224E–MAX3227E

READY TURN-ON TIME

vs. TEMPERATURE

MAX3224-7/44/45E-08

TEMPERATURE (°C)

READY TURN-ON TIME (μs)

200

180

160

140

120

100

-40 0 20-20 40 60 80 100

MAX3224E–MAX3227E

READY TURN-OFF TIME

vs. TEMPERATURE

MAX3224-7/44/45E-09

TEMPERATURE (°C)

READY TURN-OFF TIME (ns)

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

_____________________________Typical Operating Characteristics (continued)

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

-6

-5

-4

-3

-2

-1

0 1000 2000 3000 4000 5000

MAX3244E

TRANSMITTER OUTPUT VOLTAGE

vs. LOAD CAPACITANCE

MAX3224-7/44/45E-10

LOAD CAPACITANCE (pF)

TRANSMITTER OUTPUT VOLTAGE (V)

1 TRANSMITTER AT 250kbps

2 TRANSMITTERS AT 15.6kbps

VOUT+

VOUT-

0 1000 2000 3000 4000 5000

MAX3244E

SLEW RATE vs. LOAD CAPACITANCE

MAX3224-7/44/45E-11

LOAD CAPACITANCE (pF)

SLEW RATE (V/μs)

0 20001000 3000 4000 5000

MAX3244E

OPERATING SUPPLY CURRENT

vs. LOAD CAPACITANCE

MAX3224-7/44/45E-12

LOAD CAPACITANCE (pF)

SUPPLY CURRENT (mA)

250kbps

120kbps

20kbps

1 TRANSMITTER AT 250kbps

2 TRANSMITTERS AT 15.6kbps

-7.5

-2.5

-5.0

2.5

5.0

7.5

0 800400 1200 1600 2000

MAX3245E

TRANSMITTER OUTPUT VOLTAGE

vs. LOAD CAPACITANCE

MAX3224-7/44/45E-13

LOAD CAPACITANCE (pF)

TRANSMITTER OUTPUT VOLTAGE (V)

2Mbps

1.5Mbps

1Mbps

1 TRANSMITTER AT FULL DATA RATE

2 TRANSMITTERS AT 1/16 DATA RATE

100

0400 800 1200 1600 2000

MAX3245E

OPERATING SUPPLY CURRENT

vs. LOAD CAPACITANCE

MAX3224-7/44/45E-15

SUPPLY CURRENT (mA)

2Mbps

1.5Mbps

1Mbps

1 TRANSMITTER AT FULL DATA RATE

2 TRANSMITTERS AT 1/16 DATA RATE

0 400 800 1200 1600 2000

MAX3245E

SLEW RATE vs. LOAD CAPACITANCE

MAX3224-7/44/45E-14

LOAD CAPACITANCE (pF)

SLEW RATE (V/μs)

1 TRANSMITTER AT 1Mbps

2 TRANSMITTERS AT 62.5kbps

0 1000 2000 3000

MAX3245E

TRANSMITTER SKEW

vs. LOAD CAPACITANCE

MAX3224-7/44/45E-16

TRANSMITTER SKEW (ns)

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

______________________________________________________________ Pin Description

MAX3224E

MAX3225E

MAX3226E

MAX3227E

TQFN

DIP/

SSOP/

TSSOP

TQFN SSOP/

TSSOP

MAX3244E

MAX3245E

SO/ SSOP/ TSSOP

MAX3245E

TQFN

NAME FUNCTION

19 1 14 1 — — READY

Ready to Transmit Output,

active-high. READY is

enabled high when V- goes

below -4V and the device is

ready to transmit.

1 2 16 2 28 31 C1+

Positive Terminal of Voltage-

Doubler Charge-Pump

Capacitor

20 3 15 3 27 30 V+

+5.5V generated by the

charge pump

2 4 1 4 24 26 C1-

Negative Terminal of Voltage-

Doubler Charge-Pump

Capacitor

3 5 2 5 1 33 C2+

Positive Terminal of Inverting

Charge-Pump Capacitor

4 6 3 6 2 34 C2-

Negative Terminal of

Inverting Charge-Pump

Capacitor

5 7 4 7 3 35 V-

-5.5V Generated by the

Charge Pump

6, 15 8, 17 10 13 9, 10, 11 7, 8, 9 T_OUT RS-232 Transmitter Outputs

7, 14 9, 16 5 8 4-8 1-5 R_IN RS-232 Receiver Inputs

8, 13 10, 15 6 9 15-19 15, 16, 17,

19, 20 R_OUT TTL/CMOS Receiver Outputs

9 11 7 10 21 23 INVALID

Valid Signal Detector Output,

active low. A logic high

indicates that a valid RS-232

level is present on a receiver

input.

10, 11 12, 13 8 11 12-14 11, 12, 13 T_IN TTL/CMOS Transmitter Inputs

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

Pin Description (continued)

MAX3224E

MAX3225E

MAX3226E

MAX3227E

TQFN

DIP/

SSOP/

TSSOP

TQFN SSOP/

TSSOP

MAX3244E

MAX3245E

SO/ SSOP/ TSSOP

MAX3245E

TQFN

NAME FUNCTION

12 14 9 12 23 25 FORCEON

Force-On Input, Active High.

Drive high to override

AutoShutdown Plus, keeping

transmitters and receivers on

(FORCEOFF must be high)

(Table 1).

16 18 11 14 25 27 GND Ground

17 19 12 15 26 29 VCC +3.0V to +5.5V Single Supply

Voltage

18 20 13 16 22 24 FORCEOFF

Force-Off Input, Active Low.

Drive low to shut down

transmitters, receivers

(except R2OUTB), and

charge pump. This overrides

AutoShutdown Plus and

FORCEON (Table 1).

— — — — 20 21 R2OUTB

TTL/CMOS Noninverting

Complementary Receiver

Outputs. Always active.

— — — — —

6, 10, 14,

18, 22, 28,

32, 36

N.C. No Connection. Not internally

connected.

— — — — — — EP

Exposed Pad. Solder the

exposed pad to the ground

plane or leave unconnected.

_______________Detailed Description

Dual Charge-Pump Voltage Converter

The MAX3224E–MAX3227E/MAX3244E/MAX3245E’s

internal power supply consists of a regulated dual

charge pump that provides output voltages of +5.5V

(doubling charge pump) and -5.5V (inverting charge

pump), over the +3.0V to +5.5V range. The charge

pump operates in discontinuous mode: if the output

voltages are less than 5.5V, the charge pump is

enabled; if the output voltages exceed 5.5V, the

charge-pump is disabled. Each charge pump requires

a flying capacitor (C1, C2) and a reservoir capacitor

(C3, C4) to generate the V+ and V- supplies.

The READY output (MAX3224E–MAX3227E) is low

when the charge pumps are disabled in shutdown

mode. The READY signal asserts high when V- goes

below -4V.

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

RS-232 Transmitters

The transmitters are inverting level translators that

convert CMOS-logic levels to 5.0V EIA/TIA-232 levels.

The MAX3224E/MAX3226E/MAX3244E guarantee a

250kbps data rate (1Mbps, for the MAX3225E/MAX3227E/

MAX3245E) with worst-case loads of 3kΩin parallel with

1000pF, providing compatibility with PC-to-PC com-

munication software (such as LapLink®). Transmitters

can be paralleled to drive multiple receivers. Figure 1

shows a complete system connection.

When FORCEOFF is driven to ground or when the Auto-

Shutdown Plus circuitry senses that all receiver and

transmitter inputs are inactive for more than 30s, the

transmitters are disabled and the outputs go into a high-

impedance state. When powered off or shut down, the

outputs can be driven to ±12V. The transmitter inputs

do not have pullup resistors. Connect unused inputs to

GND or VCC.

MAX3244E

MAX3245E

I/O

CHIP

WITH

UART

CPU

RS-232

POWER-

MANAGEMENT

UNIT OR

KEYBOARD

CONTROLLER

FORCEOFF

FORCEON

INVALID

Figure 1. Interface Under Control of PMU

MAX3244E

MAX3245E

T1OUT

R2OUTB

5kΩ

UART

VCC

T1IN

THREE-STATED

LOGIC

TRANSITION

DETECTOR

R2IN

PROTECTION

DIODE

R2OUT

FORCEOFF = GND

VCC

μP

RS-232

UART

SHDN = GND

VCC

GND

5kΩ

a) OLDER RS-232: POWERED-DOWN UART DRAWS CURRENT FROM ACTIVE

RECEIVER OUTPUT IN SHUTDOWN.

b) NEW MAX3244E/MAX3245E: IN SHUTDOWN, R2OUTB IS USED TO MONITOR

EXTERNAL DEVICES AND R2OUT IS THREE STATED, ELIMINATING A CURRENT

PATH THROUGH THE UART'S PROTECTION DIODE.

GND

PROTECTION

DIODE

Figure 2. The MAX3244E/MAX3245E detect RS-232 activity

when the UART and interface are shut down.

LapLink is a registered trademark of Laplink Software, Inc.

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

RS-232 Transceivers with AutoShutdown Plus

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

RS-232 Receivers

The receivers convert RS-232 signals to CMOS-logic

output levels. The MAX3224E–MAX3227E feature

inverting outputs that always remain active (Table 1).

The MAX3244E/MAX3245E have inverting three-state

outputs that are high impedance when shut down

(FORCEOFF = GND) (Table 1).

The MAX3244E/MAX3245E feature an extra, always

active, noninverting output, R2OUTB. R2OUTB output

monitors receiver activity while the other receivers are

high impedance, allowing ring indicator applications to

be monitored without forward biasing other devices

connected to the receiver outputs. This is ideal for sys-

tems where VCC is set to ground in shutdown to

accommodate peripherals such as UARTs (Figure 2).

The MAX3224E–MAX3227E/MAX3244E/MAX3245E fea-

ture an INVALID output that is enabled low when no

valid RS-232 voltage levels have been detected on all

receiver inputs. Because INVALID indicates the receiv-

er input’s condition, it is independent of FORCEON and

FORCEOFF states (Figures 3 and 4).

AutoShutdown Plus Mode

The MAX3224E–MAX3227E/MAX3244E/MAX3245E

achieve a 1µA supply current with Maxim’s AutoShutdown

Plus feature, which operates when FORCEOFF is high

and a FORCEON is low. When these devices do not

sense a valid signal transition on any receiver and trans-

mitter input for 30s, the on-board charge pumps are

shut down, reducing supply current to 1µA. This occurs

if the RS-232 cable is disconnected or if the connected

Table 1. Output Control Truth Table

OPERATION

STATUS FORCEON FORCEOFF

VALID

RECEIVER

LEVEL

RECEIVER OR

TRANSMITTER

EDGE WITHIN

30s

T_OUT

R_OUT

(MAX3224E/

MAX3225E/

MAX3226E/

MAX3227E)

R_OUT

(MAX3244E/

MAX3245E)

R2OUTB

(MAX3244E/

MAX3245E)

Shutdown

(Forced Off) X 0 X X High-Z Active High-Z Active

Normal

Operation

(Forced On)

1 1 X X Active Active Active Active

Normal

Operation

(AutoShutdown

Plus)

0 1 X Yes Active Active Active Active

Shutdown (Auto-

Shutdown Plus) 0 1 X No High-Z Active Active Active

Normal

Operation INVALID*1Yes XActive Active Active Active

Normal

Operation INVALID*1 X Yes Active Active Active Active

Shutdown INVALID*1No No High-Z Active Active Active

Normal

Operation

(AutoShutdown)

INVALID*INVALID** Yes XActive Active Active Active

Shutdown

(AutoShutdown) INVALID*INVALID** No XHigh-Z Active High-Z Active

X = Don’t care

INVALID connected to FORCEON

INVALID connected to FORCEON and FORCEOFF

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

peripheral transmitters are turned off, and the UART dri-

ving the transmitter inputs is inactive. The system turns

on again when a valid transition is applied to any

RS-232 receiver or transmitter input. As a result, the sys-

tem saves power without changes to the existing BIOS

or operating system.

Figures 3a and 3b depict valid and invalid RS-232

receiver voltage levels. INVALID indicates the receiver

input’s condition, and is independent of FORCEON and

FORCEOFF states. Figure 3 and Tables 1 and 2 sum-

marize the operating modes of the MAX3224E–

MAX3227E/MAX3244E/MAX3245E. FORCEON and

FORCEOFF override AutoShutdown Plus circuitry.

When neither control is asserted, the IC selects

between these states automatically based on the last

receiver or transmitter input edge received.

When shut down, the device’s charge pumps turn off,

V+ is pulled to VCC, V- is pulled to ground, the transmit-

ter outputs are high impedance, and READY

(MAX3224E–MAX3227E) is driven low. The time

required to exit shutdown is typically 100µs (Figure 8).

By connecting FORCEON to INVALID, the MAX3224E–

MAX3227E/MAX3244E/MAX3245E shut down when no

valid receiver level and no receiver or transmitter edge is

detected for 30s, and wake up when a valid receiver

level or receiver or transmitter edge is detected.

+0.3V

-0.3V

INVALID

R_IN

INVALID ASSERTED IF ALL RECEIVER INPUTS ARE BETWEEN +0.3V AND -0.3V FOR

AT LEAST 30μs.

30μs

TIMER

+2.7V

-2.7V

INVALID

R_IN

INVALID DEASSERTED IF ANY RECEIVER INPUT HAS BEEN BETWEEN +2.7V AND -2.7V

FOR LESS THAN 30μs.

30μs

TIMER

AUTOSHDN

R_IN

T_IN

30s

TIMER

EDGE

DETECT

EDGE

DETECT

FORCEOFF

FORCEON

Figure 3a. INVALID Functional Diagram, INVALID Low

Figure 3b. INVALID Functional Diagram, INVALID High

Figure 3c. AutoShutdown Plus Logic

POWERDOWN*

AUTOSHDN

FORCEOFF

FORCEON

* POWERDOWN IS ONLY AN INTERNAL SIGNAL.

IT CONTROLS THE OPERATIONAL STATUS OF

THE TRANSMITTERS AND THE POWER SUPPLIES.

Figure 3d. Power-Down Logic

RECEIVER INPUT LEVELS

-2.7V

-0.3V

+2.7V

+0.3V

INDETERMINATE

INVALID HIGH

INVALID LOW

INVALID HIGH

INDETERMINATE

Figure 4a. Receiver Positive/Negative Thresholds for INVALID

RS-232 SIGNAL

PRESENT AT ANY

RECEIVER INPUT

INVALID OUTPUT

Yes High

No Low

Table 2. INVALID Truth Table

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

By connecting FORCEON and FORCEOFF to INVALID,

the MAX3224E–MAX3227E/MAX3244E/MAX3245E shut

down when no valid receiver level is detected and

wake up when a valid receiver level is detected (same

functionality as AutoShutdown feature on MAX3221E/

MAX3223E/MAX3243E).

A mouse or other system with AutoShutdown Plus may

need time to wake up. Figure 5 shows a circuit that

forces the transmitters on for 100ms, allowing enough

time for the other system to realize that the MAX3244E/

MAX3245E is awake. If the other system outputs valid

RS-232 signal transitions within that time, the RS-232

ports on both systems remain enabled.

Software-Controlled Shutdown

If direct software control is desired, use INVALID to

indicate DTR or ring indicator signal. Tie FORCEOFF

and FORCEON together to bypass the AutoShutdown

Plus so the line acts like a SHDN input.

±15kV ESD Protection

As with all Maxim devices, ESD-protection structures are

incorporated on all pins to protect against electrostatic

discharges encountered during handling and assembly.

The driver outputs and receiver inputs of the

MAX3224E–MAX3227E/MAX3244E/MAX3245E have extra

protection against static electricity. Maxim’s engineers

have developed state-of-the-art structures to protect

VCC

V+

V-

VCC

INVALID

OUTPUT

READY

TRANSMITTER

INPUTS

RECEIVER

INPUTS }INVALID

REGION

*MAX3224E–MAX3227E

TRANSMITTER

OUTPUTS

*VCC

tAUTOSHDN tWU tWU

tINVL tINVH tAUTOSHDN

Figure 4b. AutoShutdown Plus, INVALID, and READY Timing Diagram

FORCEON

MASTER SHDN LINE

0.1μF1MΩ

FORCEOFF

MAX3224E

MAX3225E

MAX3226E

MAX3227E

MAX3244E

MAX3245E

POWER-

MANAGEMENT

UNIT

Figure 5. AutoShutdown Plus Initial Turn-On to Wake Up a

Mouse or Another System

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

these pins against ESD of ±15kV without damage. The

ESD structures withstand high ESD in all states: normal

operation, shutdown, and powered down. After an ESD

event, Maxim’s E versions keep working without

latchup, whereas competing RS-232 products can

latch and must be powered down to remove latchup.

ESD protection can be tested in various ways; the

transmitter outputs and receiver inputs of this product

family are characterized for protection to the following

limits:

1) ±15kV using the Human Body Model

2) ±8kV using the Contact-Discharge Method specified

in IEC 1000-4-2

3) ±15kV using IEC 1000-4-2’s Air-Gap Method.

ESD Test Conditions

ESD performance depends on a variety of conditions.

Contact Maxim for a reliability report that documents

test setup, test methodology, and test results.

Human Body Model

Figure 6a shows the Human Body Model and Figure 6b

shows the current waveform it generates when dis-

charged into a low impedance. This model consists of

a 100pF capacitor charged to the ESD voltage of inter-

est, which is then discharged into the test device

through a 1.5kΩresistor.

IP 100%

90%

36.8%

tRL TIME

tDL

CURRENT WAVEFORM

PEAK-TO-PEAK RINGING

(NOT DRAWN TO SCALE)

10%

AMPERES

Figure 6b. Human Body Current Waveform

tr = 0.7ns to 1ns

30ns

60ns

100%

90%

10%

IPEAK

Figure 7b. IEC 1000-4-2 ESD Generator Current Waveform

CHARGE-CURRENT

LIMIT RESISTOR

DISCHARGE

RESISTANCE

STORAGE

CAPACITOR

100pF

RC 1MΩRD 1500Ω

HIGH-

VOLTAGE

SOURCE

DEVICE

UNDER

TEST

Figure 6a. Human Body ESD Test Model Figure 7a. IEC 1000-4-2 ESD Test Model

CHARGE CURRENT

LIMIT RESISTOR

DISCHARGE

RESISTANCE

STORAGE

CAPACITOR

150pF

RC 50MΩ to 100MΩRD 330Ω

HIGH-

VOLTAGE

SOURCE

DEVICE

UNDER

TEST

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

IEC 1000-4-2

The IEC 1000-4-2 standard covers ESD testing and per-

formance of finished equipment; it does not specifically

refer to integrated circuits. The MAX3224E–MAX3227E,

MAX3244E/MAX3245E help you design equipment that

meets Level 4 (the highest level) of IEC 1000-4-2, with-

out the need for additional ESD-protection components.

The major difference between tests done using the

Human Body Model and IEC 1000-4-2 is higher peak

current in IEC 1000-4-2, because series resistance is

lower in the IEC 1000-4-2 model. Hence, the ESD with-

stand voltage measured to IEC 1000-4-2 is generally

lower than that measured using the Human Body

Model. Figure 7a shows the IEC 1000-4-2 model and

Figure 7b shows the current waveform for the 8kV, IEC

1000-4-2, Level 4, ESD Contact-Discharge Method.

The Air-Gap Method involves approaching the device

with a charged probe. The Contact-Discharge Method

connects the probe to the device before the probe is

energized.

Machine Model

The Machine Model for ESD tests all pins using a

200pF storage capacitor and zero discharge resis-

tance. Its objective is to emulate the stress caused by

contact that occurs with handling and assembly during

manufacturing. Of course, all pins require this protec-

tion during manufacturing, not just RS-232 inputs and

outputs. Therefore, after PC board assembly, the

Machine Model is less relevant to I/O ports.

__________Applications Information

Capacitor Selection

The capacitor type used for C1–C4 is not critical for

proper operation; polarized or nonpolarized capacitors

can be used. The charge pump requires 0.1µF capaci-

tors for 3.3V operation. For other supply voltages, see

Table 3 for required capacitor values. Do not use val-

ues smaller than those listed in Table 3. Increasing the

capacitor values (e.g., by a factor of 2) reduces ripple

on the transmitter outputs and slightly reduces power

consumption. C2, C3, and C4 can be increased without

changing C1’s value. However, do not increase C1

without also increasing the values of C2, C3, C4,

and CBYPASS, to maintain the proper ratios (C1 to

the other capacitors).

When using the minimum required capacitor values,

make sure the capacitor value does not degrade

excessively with temperature. If in doubt, use capaci-

tors with a larger nominal value. The capacitor’s equiv-

alent series resistance (ESR), which usually rises at low

temperatures, influences the amount of ripple on V+

and V-.

Power-Supply Decoupling

In most circumstances, a 0.1µF VCC bypass capacitor

is adequate. In applications that are sensitive to power-

supply noise, use a capacitor of the same value as

charge-pump capacitor C1. Connect bypass capaci-

tors as close to the IC as possible.

Transmitter Outputs

when Exiting Shutdown

Figure 8 shows two transmitter outputs when exiting

shutdown mode. As they become active, the two trans-

mitter outputs are shown going to opposite RS-232 lev-

els (one transmitter input is high, the other is low). Each

VCC

(V)

C2, C3, C4

(µF)

3.0 to 3.6 0.22

3.15 to 3.6 0.1

C1, CBYPASS

(µF)

0.22

0.1

4.5 to 5.5 0.33

3.0 to 5.5 1

0.047

0.22

Table 3. Required Minimum Capacitance

Values

5μs/div

T1OUT

FORCEON = FORCEOFF

T2OUT

READY

5V/div

2V/div

5V/div

VCC = 3.3V

C1–C4 = 0.1μF

Figure 8. Transmitter Outputs when Exiting Shutdown or

Powering Up

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

transmitter is loaded with 3kΩin parallel with 1000pF.

The transmitter outputs display no ringing or undesir-

able transients as they come out of shutdown. Note that

the transmitters are enabled only when the magnitude

of V- exceeds approximately -3V.

High Data Rates

The MAX3224E/MAX3226E/MAX3244E maintain the

RS-232 ±5.0V minimum transmitter output voltage even

at high data rates. Figure 9 shows a transmitter loop-

back test circuit. Figure 10 shows a loopback test result

at 120kbps, and Figure 11 shows the same test at

250kbps. For Figure 10, all transmitters were driven

simultaneously at 120kbps into RS-232 loads in parallel

with 1000pF. For Figure 11, a single transmitter was dri-

ven at 250kbps, and all transmitters were loaded with

an RS-232 receiver in parallel with 250pF.

The MAX3225E/MAX3227E/MAX3245E maintain the

RS-232 ±5.0V minimum transmitter output voltage at

data rates up to 1Mbps (MegaBaud). Figure 12 shows

a loopback test result with a single transmitter driven at

1Mbps and all transmitters loaded with an RS-232

receiver in parallel with 250pF.

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

RS-232 Transceivers with AutoShutdown Plus

MAX3224E

MAX3225E

MAX3226E

MAX3227E

MAX3244E

MAX3245E

5kΩ

R_ IN

R_ OUT

FORCEON

C2-

C2+

C1-

C1+

V-

V+

VCC

C3*

CBYPASS

VCC

FORCEOFF

*C3 CAN BE RETURNED TO VCC OR GND.

T_ OUT

T_ IN

GND

VCC

1000pF

Figure 9. Loopback Test Circuit

Figure 10. MAX3224E/MAX3226E/MAX3244E Loopback Test

Result at 120kbps

2μs/div

T1IN

T1OUT

R1OUT

5V/div

VCC = 3.3V

Figure 11. MAX3224E/MAX3226E/MAX3244E Loopback Test

Result at 250kbps

2μs/div

T1IN

T1OUT

R1OUT

5V/div

VCC = 3.3V

Figure 12. MAX3225E/MAX3227E/MAX3245E Loopback Test

Result at 1Mbps

200ns/div

T1IN

T1OUT

R1OUT

5V/div

VCC = 3.3V

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

Figure 13a. Mouse Driver Test Circuit

COMPUTER SERIAL PORT

-V

GND

SERIAL

MOUSE

MAX3244E

MAX3245E

FORCEOFF

R5OUT

R4OUT

R3OUT

R2OUT

R1OUT

R2OUTB

LOGIC

OUTPUTS

5kΩ

R5IN 8

R4IN 7

R3IN 6

R2IN 5

R1IN 4

RS-232

INPUTS

GND

LOGIC

INPUTS

T3IN

T2IN

T1IN

C2-

C2+

C1-

C1+

T3OUT 11

T2OUT 10

T1OUT 9

V-

V+

VCC

0.1μF

0.1μF 26

0.1μF

FORCEON

INVALID

TO POWER-

MANAGEMENT

UNIT

+3.3V

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

Mouse Driveability

The MAX3244E/MAX3245E are specifically designed to

power serial mice while operating from low-voltage

power supplies. They have been tested with leading

mouse brands from manufacturers such as Microsoft

and Logitech. The MAX3244E/MAX3245E successfully

drove all serial mice tested and met their respective

current and voltage requirements. The MAX3244E/

MAX3245E dual charge pump ensures the transmitters

supply at least ±5V during worst-case conditions.

Figure 13b shows the transmitter output voltages under

increasing load current. Figure 13a shows a typical

mouse connection.

Interconnection with 3V and 5V Logic

The MAX3224E–MAX3227E/MAX3244E/MAX3245E can

directly interface with various 5V logic families, includ-

ing ACT and HCT CMOS. See Table 4 for more informa-

tion on possible combinations of interconnections.

Table 5 lists other Maxim ESD-powered transceivers.

SYSTEM

POWER-SUPPLY

VOLTAGE (V)

COMPATIBILITY

3.3 Compatible with all CMOS families

5Compatible with all TTL and CMOS families

VCC SUPPLY

VOLTAGE

(V)

3.3

5Compatible with ACT and HCT CMOS, and with AC, HC, or CD4000 CMOS3.3

PART

SUPPLY

VOLTAGE

RANGE

(V)

NO.

Tx/Rx

GUARANTEED

DATA RATE

(kbps)

MAX3241E +3.0 to +5.5 3/5 250

MAX3243E +3.0 to +5.5 3/5 250

MAX3244E +3.0 to +5.5 3/5 250

MAX3245E +3.0 to +5.5 3/5 1Mbps

MAX3232E +3.0 to +5.5 2/2 250

MAX3222E +3.0 to +5.5 2/2 250

MAX3223E +3.0 to +5.5 2/2 250

MAX3224E +3.0 to +5.5 2/2 250

MAX3225E +3.0 to +5.5 2/2 1Mbps

MAX3221E +3.0 to +5.5 1/1 250

MAX3227E +3.0 to +5.5 1/1 1Mbps

MAX3226E +3.0 to +5.5 1/1 250

SUPPLY

CURRENT

(µA)

300

Auto-

Shutdown

Plus

—

Yes

—

Yes

—

Yes

Auto-

Shutdown

—

Yes

—

Yes

—

Yes

—

Human

Body

Model

(kV)

±15

IEC 1000-4-2

Contact

Discharge

(kV)

±8

IEC 1000-4-2

Air-Gap

Discharge

(kV)

±15

Figure 13b. MAX324_E Transmitter Output Voltage vs. Load

Current per Transmitter

-6

-5

-4

-3

-2

-1

012345678910

MAX2343E-FIG15

LOAD CURRENT PER TRANSMITTER (mA)

TRANSMITTER OUTPUT VOLTAGE (V)

VOUT+

VOUT-

VOUT+

VOUT-

VCC

VCC = 3.0V

Table 5. ±15kV ESD-Protected, 3.0V to 5.5V Powered RS-232 Transceivers from Maxim

Table 4. Logic Family Compatibility with Various Supply Voltages

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

MAX3244E***

MAX3245E

FORCEON

R5OUT

R4OUT

R3OUT

R2OUT

R1OUT

R2OUTB

FORCEOFF

R5IN 8

R4IN 7

R3IN 6

R2IN 5

R1IN 4

GND

T3IN

T2IN

T1IN

C2-

C2+

C1-

C1+

T3OUT 11

T2OUT 10

T1OUT 9

V- 3

V+ 27

VCC

0.1μF

CBYPASS

0.1μF

+3.3V

INVALID 21

MAX3226E*

MAX3227E

FORCEON

READY AutoShutdown

Plus

R1OUT9

FORCEOFF 16

INVALID 10

GND

T1IN

C2-

C2+

C1-

C1+

R1IN 8

T1OUT 13

V- 7

V+ 3

VCC

0.1μF

0.1μF 15

0.1μF

CBYPASS

+3.3V

TO POWER-

MANAGEMENT

UNIT

5kΩ

MAX3224E**

MAX3225E

FORCEON

READY

R2OUT10

R1OUT15

FORCEOFF 20

INVALID 11

R2IN 9

GND

RS-232

OUTPUTS

TTL/CMOS

INPUTS T2IN

T1IN

C2-

C2+

C1-

C1+

R1IN 16

T2OUT 8

T1OUT 17

V- 7

V+ 3

VCC

0.1μF

0.1μF 19

0.1μF

+3.3V

RS-232

INPUTS

TO POWER-

MANAGEMENT

UNIT

TTL/CMOS

OUTPUTS 5kΩ

5kΩ

AutoShutdown

Plus

AutoShutdown

Plus

*MAX3226E/MAX3227E PIN OUT REFERS TO SSOP/TSSOP PACKAGES.

**MAX3224E/MAX3225E PIN OUT REFERS TO DIP/ SSOP/TSSOP PACKAGES.

***MAX3244E/MAX3245E PIN OUT REFERS TO SO/SSOP/TSSOP PACKAGES.

___________________________________________________Typical Operating Circuits

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

READY

C1+

V+

C1-

C2+

C2-

V-

R1IN

FORCEOFF

VCC

GND

T1OUT

FORCEON

T1IN

INVALID

R1OUT

MAX3226E

MAX3227E

SSOP/TSSOP

C1+

V+

VCC

GND

C1-

FORCEON

FORCEOFF

INVALID

R2OUTB

R1OUT

R2OUT

R3OUT

R4OUT

R5OUT

C2+

C2-

V-

R1IN

R2IN

R3IN

R4IN

R5IN

T1OUT

T2OUT

T3OUT

T3IN

T2IN

T1IN

SO/SSOP/TSSOP

MAX3244E

MAX3245E

FORCEOFF

VCC

GND

T1OUT

C1-

V+

C1+

READY

R1IN

R1OUT

FORCEON

T1IN

T2OUT

V-

C2-

C2+

T2IN

INVALIDR2OUT

R2IN

DIP/SSOP/TSSOP

MAX3224E

MAX3225E

GND

C1-

FORCEOFF

INVALID

R1OUT

R2OUT

N.C.

R2OUTB

FORCEON

R3IN

R4IN

R5IN

T1OUT

T2OUT

T3OUT

R1IN 1

10 11 12 13 14 15 16 17 18

N.C.

R5OUT

R4OUT

N.C.

T1IN

T2IN

T3IN

N.C.

V-

C2-

C2+

N.C.

C1+

V+

VCC

N.C.

TQFN

MAX3245E

TOP VIEW

*EP

N.C.

R3OUT

R2IN

36 35 34 33 32 31 30 29 28

C2+

V-

C1-

GND

FORCEON

VCC

READY

12 11 9

V+

C1+

T1IN

INVALID

R1OUT

R1IN

MAX3226E

MAX3227E

C2- T1OUT

*EP

*CONNECT EP TO GND.

TQFN

TOP VIEW

MAX3224E

MAX3225E

TQFN

TOP VIEW

C1-

C2-

V-

C1+

R1IN

FORCEON

T1IN

T1OUT

FORCEOFF

15 14 12 11

READY

V+

INVALID

R2OUT

R2IN

T2OUT

C2+ R1OUT

VCC

16 10 T2IN

GND

*EP

FORCEOFF

___________________________________________________________ Pin Configurations

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

Ordering Information (continued) Chip Information

PROCESS: BICMOS

Package Information

For the latest package outline information and land patterns

(footprints), go to www.maxim-ic.com/packages. Note that a

“+”, “#”, or “-” in the package code indicates RoHS status only.

Package drawings may show a different suffix character, but the

drawing pertains to the package regardless of RoHS status.

PART TEMP RANGE PIN-PACKAGE

MAX3225ECUP+ 0°C to +70°C 20 TSSOP

MAX3225ECTP+ 0°C to +70°C 20 TQFN-EP*

MAX3225ECAP+ 0°C to +70°C 20 SSOP

MAX3225ECPP+ 0°C to +70°C 20 Plastic DIP

MAX3225EETP+ -40°C to +85°C 20 TQFN -EP*

MAX3225EEUP+ -40°C to +85°C 20 TSSOP

MAX3225EEAP+ -40°C to +85°C 20 SSOP

MAX3225EEPP+ -40°C to +85°C 20 Plastic DIP

MAX3225EAAP+ -40°C to +125°C 20 SSOP

MAX3226ECTE+ 0°C to +70°C 16 TQFN-EP*

MAX3226ECUE+ 0°C to +70°C 16 TSSOP

MAX3226ECAE+ 0°C to +70°C 16 SSOP

MAX3226EEAE+ -40°C to +85°C 16 SSOP

MAX3226EETE+ -40°C to +85°C 16 TQFN-EP*

MAX3226EEUE+ -40°C to +85°C 16 TSSOP

MAX3226EAAE+ -40°C to +125°C 16 SSOP

MAX3227ECAE+ 0°C to +70°C 16 SSOP

MAX3227ECTE+ 0°C to +70°C 16 TQFN-EP*

MAX3227ECUE+ 0°C to +70°C 16 TSSOP

MAX3227EEAE+ -40°C to +85°C 16 SSOP

MAX3227EEAE/V+ -40°C to +85°C 16 SSOP

MAX3227EETE+ -40°C to +85°C 16 TQFN-EP*

MAX3227EEUE+ -40°C to +85°C 16 TSSOP

MAX3227EAAE+ -40°C to +125°C 16 SSOP

MAX3244ECWI+ 0°C to +70°C 28 Wide SO

MAX3244ECAI+ 0°C to +70°C 28 SSOP

MAX3244ECUI+ 0°C to +70°C 28 TSSOP

MAX3244EEWI+ -40°C to +85°C 28 Wide SO

MAX3244EEAI+ -40°C to +85°C 28 SSOP

MAX3244EEUI+ -40°C to +85°C 28 TSSOP

MAX3245ECWI+ 0°C to +70°C 28 Wide SO

MAX3245ECAI+ 0°C to +70°C 28 SSOP

MAX3245ECTX+ 0°C to +70°C 36 TQFN- EP*

MAX3245EEAI+ -40°C to +85°C 28 SSOP

MAX3245EEWI+ -40°C to +85°C 28 WIDE SO

MAX3245EEUI+ -40°C to +85°C 28 TSSOP

MAX3245EETX+ -40°C to +85°C 36 TQFN- EP*

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

EP = Exposed pad.

/V denotes an automotive qualified part.

PACKAGE

TYPE

PACKAGE

CODE

OUTLINE

NO.

LAND

PATTERN NO.

16 SSOP A16+2 21-0056 90-0106

16 TSSOP U16+1 21-0066 90-0117

16 TQFN-EP T1655+2 21-0140 90-0072

20 DIP P20+3 21-0043 —

20 SSOP A20+1 21-0056 90-0094

20 TSSOP U20+2 21-0066 90-0116

20 TQFN-EP T2055+5 21-0140 90-0010

28 Wide SO W28+6 21-0042 90-0109

28 SSOP A28+1 21-0056 90-0095

28 TSSOP U28+2 21-0066 90-0171

36 TQFN T3666+3 21-0141 90-0050

Maxim Integrated

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

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

RS-232 Transceivers with AutoShutdown Plus

Revision History

REVISION

NUMBER

REVISION

DATE DESCRIPTION PAGES

CHANGED

10 3/11

Added an automotive qualified part to the Ordering Information; changed all the

parts listed in the Ordering Information to lead free 1, 20

MAX3224E/MAX3225E/

MAX3226E/MAX3227E/MAX3244E/MAX3245E

Maxim Integrated 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-1000

Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied.

Maxim reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical

Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.

Mouser Electronics

Authorized Distributor

Click to View Pricing, Inventory, Delivery & Lifecycle Information:

Maxim Integrated:

MAX3224ECAP+ MAX3224EEAP+ MAX3225ECAP+ MAX3225EEAP+ MAX3225EEUP+ MAX3226ECAE+

MAX3226EEAE+ MAX3226EETE+ MAX3227ECAE+ MAX3227EEAE+ MAX3227EEUE+ MAX3244ECAI+

MAX3244EEAI+ MAX3245ECAI+ MAX3245EEAI+ MAX3227EEAE/V+ MAX3227EETE+G071 MAX3245EETX+G071

MAX3245EETX+TG071 MAX3227EETE+TG071 MAX3227EEAE/V+T MAX3224ECAP+T MAX3224ECPP+

MAX3224ECUP+ MAX3224ECUP+T MAX3224EEAP+T MAX3224EEPP+ MAX3224EETP+ MAX3224EETP+T

MAX3224EEUP+ MAX3224EEUP+T MAX3225ECAP+T MAX3225ECTP+ MAX3225ECTP+T MAX3225ECUP+

MAX3225ECUP+T MAX3225EEAP+T MAX3225EEPP+ MAX3225EETP+ MAX3225EETP+T MAX3225EEUP+T

MAX3226ECAE+T MAX3226ECTE+ MAX3226ECTE+T MAX3226ECUE+ MAX3226ECUE+T MAX3226EEAE+T

MAX3226EETE+T MAX3226EEUE+ MAX3226EEUE+T MAX3227ECTE+ MAX3227ECTE+T MAX3227ECUE+

MAX3227ECUE+T MAX3227EEAE+T MAX3227EETE+ MAX3227EETE+T MAX3227EEUE+T MAX3244ECUI+

MAX3244ECUI+T MAX3244ECWI+ MAX3244ECWI+T MAX3244EEAI+T MAX3244EEUI+ MAX3244EEUI+T

MAX3244EEWI+ MAX3244EEWI+T MAX3245ECAI+T MAX3245ECTX+ MAX3245ECTX+T MAX3245ECUI+

MAX3245ECUI+T MAX3245ECWI+ MAX3245ECWI+T MAX3245EEAI+T MAX3245EETX+ MAX3245EETX+T

MAX3245EEUI+ MAX3245EEUI+T MAX3245EEWI+ MAX3245EEWI+T MAX3244ECAI+T MAX3227ECAE+T

MAX3224EAAP/GG8-T MAX3225EAAP+ MAX3227EAAE MAX3225EAAP MAX3227EAAE+ MAX3226EAAE+

MAX3226EAAE MAX3225ECPP