MAX3224E/MAX3225E/
MAX3226E/MAX3227E/
E
L
AVAILAB
MAX3244E/MAX3245E
±15kV ESD-Protected, 1µA, 1Mbps, 3.0V to 5.5V,
RS-232 Transceivers with AutoShutdown Plus
________________General Description
The MAX3224E/MAX3225E/MAX3226E/MAX3227E/
MAX3244E/MAX3245E 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, ±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 receiver 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 highspeed applications such as communicating with ISDN
modems. The MAX3224E/MAX3226E/MAX3244E guarantee 250kbps operation. The 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 charge pump requires
only four small 0.1µF capacitors for operation from a
3.3V supply. The MAX3224E–MAX3227E feature a logiclevel output (READY)
that asserts when
the charge
Functional
Diagrams
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
Ordering Information
PART
TEMP RANGE
MAX3224ECTP+
0°C to +70°C
PIN-PACKAGE
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
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
Ordering Information continued at end of data sheet.
_____________________ Selector Guide
PART
NO. OF
GUARANTEED
READY
DRIVERS/
DATA RATE
OUTPUT
RECEIVERS
(bps)
AutoShutdown
Plus
MAX3224E
2/2
250k
✔
✔
MAX3225E
MAX3226E
MAX3227E
2/2
1/1
1/1
1M
250k
1M
✔
✔
✔
✔
✔
✔
MAX3244E
MAX3245E
3/5
3/5
250k
1M
—
—
✔
✔
Pin Configurations appear at end of data sheet.
Functional Diagrams continued at end of data sheet.
AutoShutdown Plus, MegaBaud, and UCSP are trademarks of
UCSP
a trademark
of Maxim
Integrated Products, Inc.
MaximisIntegrated
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.
19-1339; Rev 10; 3/11
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
VCC to GND ..............................................................-0.3V to +6V
20-Pin TQFN (derate 21.3mW/°C above +70°C) ....1702.1mW
V+ to GND (Note 1) ..................................................-0.3V to +7V
20-Pin Plastic DIP (derate 11.11mW/°C above +70°C) ...889mW
V- to GND (Note 1) ...................................................+0.3V to -7V
20-Pin SSOP (derate 8.00mW/°C above +70°C) .........640mW
V+ + ⏐V-⏐(Note 1) ................................................................+13V
20-Pin TSSOP (derate 10.9mW/°C above +70°C) .......879mW
Input Voltages
28-Pin Wide SO (derate 12.5mW/°C above +70°C)............1W
T_IN, FORCEON, FORCEOFF to GND ................ -0.3V to +6V
28-Pin SSOP (derate 9.52mW/°C above +70°C) .........762mW
R_IN to GND ....................................................................±25V
28-Pin TSSOP (derate 12.8mW/°C above +70°C) .......1026mW
Output Voltages
36-Pin TQFN (derate 26.3mW/°C above +70°C)...........2105mW
T_OUT to GND.............................................................±13.2V
Operating Temperature Ranges
R_OUT, INVALID, READY to GND .........-0.3V to (VCC + 0.3V)
MAX32_ _EC_ _ .................................................0°C to +70°C
Short-Circuit Duration
MAX32_ _EE_ _................................................-40°C to +85°C
T_OUT to GND .......................................................Continuous
MAX32_ _EAA_ ..............................................-40°C to +125°C
Continuous Power Dissipation (TA = +70°C)
Storage Temperature Range .............................-65°C to +160°C
16-Pin SSOP (derate 7.14mW/°C above +70°C) .........571mW
Lead Temperature (soldering, 10s) .................................+300°C
16-Pin TSSOP (derate 9.4mW/°C above +70°C) ......754.7mW
Soldering Temperature (reflow) .......................................+260°C
16-Pin TQFN (derate 20.8mW/°C above +70°C) ....1666.7mW
Note 1: V+ and V- can have maximum magnitudes of 7V, but their absolute difference cannot exceed 13V.
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.
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.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DC CHARACTERISTICS (VCC = 3.3V or 5.0V, TA = +25°C)
Supply Current,
AutoShutdown Plus
FORCEON = GND, FORCEOFF = VCC,
all R_IN idle, all T_IN idle
1
10
µA
Supply Current, Shutdown
FORCEOFF = GND
1
10
µA
Supply Current,
AutoShutdown Plus Disabled
FORCEON = FORCEOFF = VCC, no load
0.3
1
mA
0.8
V
LOGIC INPUTS AND RECEIVER OUTPUTS
Input Logic Threshold Low
T_IN, FORCEON, FORCEOFF
Input Logic Threshold High
T_IN, FORCEON,
FORCEOFF
VCC = 3.3V
2
VCC = 5.0V
2.4
Transmitter Input Hysteresis
V
0.5
V
T_IN, FORCEON, FORCEOFF
±0.01
±1
µA
Output Leakage Current
R_OUT (MAX3244E/MAX3245E), receivers
disabled
±0.05
±10
µA
Output Voltage Low
IOUT = 1.6mA
0.4
V
Output Voltage High
IOUT = -1.0mA
Input Leakage Current
VCC - 0.6 VCC - 0.1
V
RECEIVER INPUTS
Input Voltage Range
-25
Input Threshold Low
TA = +25°C
Input Threshold High
TA = +25°C
0.6
1.2
VCC = 5.0V
0.8
1.5
1.5
2.4
VCC = 5.0V
1.8
2.4
2
0.5
TA = +25°C
3
5
V
V
VCC = 3.3V
Input Hysteresis
Input Resistance
+25
VCC = 3.3V
V
V
7
kΩ
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.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
TRANSMITTER OUTPUTS
Output Voltage Swing
All transmitter outputs loaded with 3kΩ to
ground
±5
±5.4
V
Output Resistance
VCC = V+ = V- = 0V, transmitter outputs = ±2V
300
10M
Ω
Output Short-Circuit Current
VCC = 0V or 3V to 5.5V, VOUT = ±12V,
Transmitters disabled
Output Leakage Current
±60
mA
±25
µA
MOUSE DRIVEABILITY (MAX3244E/MAX3245E)
T1IN = T2IN = GND, T3IN = VCC,
T3OUT loaded with 3kΩ to GND,
T1OUT and T2OUT loaded with
2.5mA each
Transmitter Output Voltage
±5
V
ESD PROTECTION
IEC 1000-4-2 Air Discharge
R_IN, T_OUT
±15
IEC 1000-4-2 Contact Discharge
±8
Human Body Model
±15
kV
AutoShutdown Plus (FORCEON = GND, FORCEOFF = VCC)
Receiver Input Threshold to
INVALID Output High
Figure 4a
Receiver Input Threshold to
INVALID Output Low
Figure 4a
INVALID, READY
Output Voltage Low
(MAX3224E–MAX3227E)
IOUT = -1.6mA
INVALID, READY
Output Voltage High
(MAX3224E–MAX3227E)
IOUT = -1.0mA
Positive threshold
Negative threshold
2.7
-2.7
-0.3
V
+0.3
V
0.4
V
VCC - 0.6
V
Receiver Positive or Negative
Threshold to INVALID High
tINVH
VCC = 5V, Figure 4b
1
µs
Receiver Positive or Negative
Threshold to INVALID Low
tINVL
VCC = 5V, Figure 4b
30
µs
Receiver or Transmitter Edge to
Transmitters Enabled
tWU
VCC = 5V, Figure 5b (Note 2)
100
µs
Receiver or Transmitter Edge to
tAUTOSHDN VCC = 5V, Figure 5b (Note 2)
Transmitters Shutdown
Maxim Integrated
15
30
60
s
3
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.)
PARAMETER
SYMBOL
tPHL
tPLH
Receiver Output Enable Time
Receiver Output Disable Time
Transmitter Skew
Receiver Skew
MIN
RL = 3kΩ, CL = 1000pF,
one transmitter switching
Maximum Data Rate
Receiver Propagation Delay
CONDITIONS
⏐ tPHL - tPLH ⏐
⏐ tPHL - tPLH ⏐
MAX
250
UNITS
kbps
0.15
R_IN to R_OUT, CL = 150pF
µs
0.15
Normal operation (MAX3244E only)
200
ns
Normal operation (MAX3244E only)
200
ns
(Note 3)
100
ns
50
ns
VCC = 3.3V, TA = +25°C,
RL = 3kΩ to 7kΩ,
measured from +3V to -3V
or -3V to +3V, one transmitter switching
Transition-Region Slew Rate
TYP
CL = 150pF
to 1000pF
6
30
V/µs
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.)
PARAMETER
SYMBOL
Maximum Data Rate
Receiver Propagation Delay
tPHL
tPLH
CONDITIONS
MIN
RL = 3kΩ, CL = 1000pF,
one transmitter switching
250
VCC = 3.0V to 4.5V, RL = 3kΩ,
CL = 250pF, one transmitter switching
1000
VCC = 4.5V to 5.5V, RL = 3kΩ,
CL = 1000pF, one transmitter switching
1000
R_IN to R_OUT, CL = 150pF
TYP
MAX
kbps
0.15
µs
0.15
Receiver Output Enable Time
Normal operation (MAX3245E only)
200
ns
Receiver Output Disable Time
Normal operation (MAX3245E only)
200
ns
(Note 3)
25
ns
50
ns
Transmitter Skew
Receiver Skew
⏐ tPHL - tPLH ⏐
⏐ tPHL - tPLH ⏐
VCC = 3.3V, TA = +25°C,
RL = 3kΩ to 7kΩ, CL = 150pF to 1000pF,
Transition-Region Slew Rate
24
150
measured from +3V to -3V or -3V to +3V,
one transmitter switching
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.
4
UNITS
V/µs
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 3kΩ and CL, TA = +25°C, unless otherwise noted.)
12
-SLEW
10
+SLEW
8
6
40
4
-3
-4
-5
-6
VOUT3000
4000
5000
0
1000
2000
3000
4000
0
5000
4000
-SLEW
50
+SLEW
40
30
80
1 TRANSMITTER AT 1Mbps
1 TRANSMITTER AT 62.5kbps (MAX3225E)
1500
2000
2500
500
LOAD CAPACITANCE (pF)
MAX3225E/MAX3227E
TRANSMITTER SKEW
vs. LOAD CAPACITANCE
30
25
20
AVERAGE: 10 PARTS
15
2000
LOAD CAPACITANCE (pF)
Maxim Integrated
2500
3000
0
500
1000
1500
2000
MAX3224E–MAX3227E
READY TURN-ON TIME
vs. TEMPERATURE
MAX3224E–MAX3227E
READY TURN-OFF TIME
vs. TEMPERATURE
28
26
20
1Mbps
LOAD CAPACITANCE (pF)
30
0
30
2500
32
22
1.5Mbps
40
LOAD CAPACITANCE (pF)
34
5
1500
2000
36
24
1000
1500
38
10
500
1000
MAX3224-7/44/45E-08
1 TRANSMITTER AT 512kbps
1 TRANSMITTER AT 30kbps
(MAX3225E)
LOAD = 3kΩ + CL
READY TURN-ON TIME (μs)
MAX3224-7/44/45E-07
50
50
0
0
200
180
READY TURN-OFF TIME (ns)
1000
2Mbps
60
10
0
500
70
2500
MAX3224-7/44/45E-09
-7.5
1 TRANSMITTER AT FULL DATA RATE
1 TRANSMITTER AT 1/16 DATA RATE
(MAX3225E)
LOAD = 3kΩ + CL
90
20
10
MAX3224-7/44/45E-06
60
5000
100
SUPPLY CURRENT (mA)
70
SLEW RATE (V/μs)
1Mbps
MAX3224-7/44/45E-05
MAX3224-7/44/45E-04
80
-5.0
0
3000
MAX3225E/MAX3227E
OPERATING SUPPLY CURRENT
vs. LOAD CAPACITANCE
20
35
2000
MAX3225E/MAX3227E
SLEW RATE vs. LOAD CAPACITANCE
1 TRANSMITTER AT FULL DATA RATE
1 TRANSMITTER AT 1/16 DATA RATE
(MAX3225E)
LOAD = 3kΩ + CL
1.5Mbps 1Mbps
2Mbps
40
1000
MAX3225E/MAX3227E
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
1.5Mbps
45
T1 TRANSMITTING AT 250kbps
T2 (MAX3224E) TRANSMITTING AT 15.6kbps
LOAD CAPACITANCE (pF)
2.5
0
20kbps
15
LOAD CAPACITANCE (pF)
2Mbps
-2.5
20
LOAD CAPACITANCE (pF)
5.0
0
120kbps
25
0
0
2000
30
5
FOR DATA RATES UP TO 250kbps
1000
250kbps
35
10
2
7.5
TRANSMITTER SKEW (ns)
45
MAX3224-7/44/45E-03
14
SLEW RATE (V/μs)
T1 TRANSMITTING AT 250kbps
T2 (MAX3224E) TRANSMITTING AT 15.6kbps
0
TRANSMITTER OUTPUT VOLTAGE (V)
16
SUPPLY CURRENT (mA)
VOUT+
MAX3224-7/44/45E-02
6
5
4
3
2
1
0
-1
-2
MAX3224E/MAX3226E
OPERATING SUPPLY CURRENT
vs. LOAD CAPACITANCE
MAX3224E/MAX3226E
SLEW RATE vs. LOAD CAPACITANCE
MAX3224-7/44/45E-01
TRANSMITTER OUTPUT VOLTAGE (V)
MAX3224E/MAX3226E
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
160
140
120
100
80
60
40
20
0
-40
-20
0
20
40
60
TEMPERATURE (°C)
80
100
-40
-20
0
20
40
60
80
100
TEMPERATURE (°C)
5
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 3kΩ and CL, TA = +25°C, unless otherwise noted.)
10
8
6
4
1000
2000
3000
4000
0
1000
2000
3000
4000
0
1000
1.5Mbps
1Mbps
1 TRANSMITTER AT FULL DATA RATE
2 TRANSMITTERS AT 1/16 DATA RATE
-2.5
2Mbps
3000
4000
5000
1.5Mbps 1Mbps
MAX3224-7/44/45E-14
2Mbps
70
60
SLEW RATE (V/μs)
5.0
2.5
2000
LOAD CAPACITANCE (pF)
MAX3245E
SLEW RATE vs. LOAD CAPACITANCE
MAX3224-7/44/45E-13
50
40
30
20
-5.0
10
1 TRANSMITTER AT 1Mbps
2 TRANSMITTERS AT 62.5kbps
0
-7.5
400
800
1200
1600
800
1200
1600
LOAD CAPACITANCE (pF)
MAX3245E
OPERATING SUPPLY CURRENT
vs. LOAD CAPACITANCE
MAX3245E
TRANSMITTER SKEW
vs. LOAD CAPACITANCE
MAX3224-7/44/45E-15
90
80
2Mbps
60
400
LOAD CAPACITANCE (pF)
100
70
0
2000
1.5Mbps
50
40
30
1Mbps
50
45
40
TRANSMITTER SKEW (ns)
0
2000
MAX3224-7/44/45E-16
TRANSMITTER OUTPUT VOLTAGE (V)
20kbps
20
LOAD CAPACITANCE (pF)
7.5
SUPPLY CURRENT (mA)
30
5000
MAX3245E
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
35
30
25
20
15
10
20
1 TRANSMITTER AT FULL DATA RATE
2 TRANSMITTERS AT 1/16 DATA RATE
10
5
0
0
0
6
120kbps
0
5000
LOAD CAPACITANCE (pF)
0
250kbps
40
10
0
0
1 TRANSMITTER AT 250kbps
2 TRANSMITTERS AT 15.6kbps
50
2
VOUT-
MAX3224-7/44/45E-12
MAX3224-7/44/45E-11
1 TRANSMITTER AT 250kbps
2 TRANSMITTERS AT 15.6kbps
12
60
SUPPLY CURRENT (mA)
VOUT+
0
-1
-2
-3
-4
-5
-6
14
MAX3224-7/44/45E-10
6
5
4
3
2
1
MAX3244E
OPERATING SUPPLY CURRENT
vs. LOAD CAPACITANCE
MAX3244E
SLEW RATE vs. LOAD CAPACITANCE
SLEW RATE (V/μs)
TRANSMITTER OUTPUT VOLTAGE (V)
MAX3244E
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
400
800
1200
1600
2000
0
1000
2000
3000
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
PIN
MAX3224E
MAX3225E
TQFN
DIP/
SSOP/
TSSOP
MAX3226E
MAX3227E
TQFN
SSOP/
TSSOP
MAX3244E
MAX3245E
SO/ SSOP/ TSSOP
MAX3245E
TQFN
NAME
FUNCTION
Ready to Transmit Output,
active-high. READY is
enabled high when V- goes
below -4V and the device is
ready to transmit.
19
1
14
1
—
—
READY
1
2
16
2
28
31
C1+
20
3
15
3
27
30
V+
+5.5V generated by the
charge pump
2
4
1
4
24
26
C1-
Negative Terminal of VoltageDoubler 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
7, 14
9, 16
5
8
4-8
1-5
R_IN
15-19
15, 16, 17,
19, 20
R_OUT
TTL/CMOS Receiver Outputs
8, 13
10, 15
6
9
Positive Terminal of VoltageDoubler Charge-Pump
Capacitor
RS-232 Transmitter Outputs
RS-232 Receiver Inputs
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
7
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)
PIN
MAX3224E
MAX3225E
TQFN
DIP/
SSOP/
TSSOP
MAX3226E
MAX3227E
TQFN
SSOP/
TSSOP
MAX3244E
MAX3245E
SO/ SSOP/ TSSOP
NAME
FUNCTION
Force-On Input, Active High.
Drive high to override
AutoShutdown Plus, keeping
transmitters and receivers on
(FORCEOFF must be high)
(Table 1).
12
14
9
12
23
25
FORCEON
16
18
11
14
25
27
GND
Ground
17
19
12
15
26
29
VCC
+3.0V to +5.5V Single Supply
Voltage
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).
18
20
13
16
22
24
FORCEOFF
—
—
—
—
20
21
R2OUTB
—
—
—
—
—
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
8
MAX3245E
TQFN
TTL/CMOS Noninverting
Complementary Receiver
Outputs. Always active.
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
±15kV ESD-Protected, 1µA, 1Mbps 3.0V to 5.5V,
RS-232 Transceivers with AutoShutdown Plus
POWERMANAGEMENT
UNIT OR
KEYBOARD
CONTROLLER
VCC
FORCEOFF
FORCEON
INVALID
PROTECTION
DIODE
MAX3244E
MAX3245E
PREVIOUS
RS-232
VCC
I
Rx
5kΩ
UART
Tx
CPU
GND
I/O
CHIP
WITH
UART
SHDN = GND
RS-232
a)
OLDER RS-232: POWERED-DOWN UART DRAWS CURRENT FROM ACTIVE
RECEIVER OUTPUT IN SHUTDOWN.
VCC
TO
μP
LOGIC
TRANSITION
DETECTOR
Figure 1. Interface Under Control of PMU
I
PROTECTION
DIODE
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 3kΩ in parallel with
1000pF, providing compatibility with PC-to-PC communication 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 AutoShutdown 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 highimpedance 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
R2OUTB
VCC
Rx
UART
5kΩ
Tx
GND
b)
R2IN
R2OUT
THREE-STATED
T1IN
T1OUT
FORCEOFF = GND
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.
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.
Maxim Integrated
9
MAX3224E/MAX3225E/
MAX3226E/MAX3227E/MAX3244E/MAX3245E
±15kV ESD-Protected, 1µA, 1Mbps 3.0V to 5.5V,
RS-232 Transceivers with AutoShutdown Plus
Table 1. Output Control Truth Table
RECEIVER OR
TRANSMITTER
EDGE WITHIN
30s
T_OUT
R_OUT
(MAX3224E/
MAX3225E/
MAX3226E/
MAX3227E)
R_OUT
(MAX3244E/
MAX3245E)
R2OUTB
(MAX3244E/
MAX3245E)
FORCEON
FORCEOFF
VALID
RECEIVER
LEVEL
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 (AutoShutdown Plus)
0
1
X
No
High-Z
Active
Active
Active
Normal
Operation
INVALID*
1
Yes
X
Active
Active
Active
Active
Normal
Operation
INVALID*
1
X
Yes
Active
Active
Active
Active
Shutdown
INVALID*
1
No
No
High-Z
Active
Active
Active
Normal
Operation
(AutoShutdown)
INVALID*
INVALID**
Yes
X
Active
Active
Active
Active
Shutdown
(AutoShutdown)
INVALID*
INVALID**
No
X
High-Z
Active
High-Z
Active
OPERATION
STATUS
X = Don’t care
* INVALID connected to FORCEON
** INVALID connected to FORCEON and FORCEOFF
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 systems where V CC is set to ground in shutdown to
accommodate peripherals such as UARTs (Figure 2).
10
The MAX3224E–MAX3227E/MAX3244E/MAX3245E feature 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 receiver 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 transmitter 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
Maxim Integrated
MAX3224E/MAX3225E/
MAX3226E/MAX3227E/MAX3244E/MAX3245E
±15kV ESD-Protected, 1µA, 1Mbps 3.0V to 5.5V,
RS-232 Transceivers with AutoShutdown Plus
+0.3V
T_IN
R_IN
30μs
TIMER
R
-0.3V
INVALID
R_IN
EDGE
DETECT
S
30s
TIMER
EDGE
DETECT
INVALID ASSERTED IF ALL RECEIVER INPUTS ARE BETWEEN +0.3V AND -0.3V FOR
AT LEAST 30μs.
Figure 3a. INVALID Functional Diagram, INVALID Low
FORCEOFF
AUTOSHDN
R
FORCEON
Figure 3c. AutoShutdown Plus Logic
+2.7V
FORCEOFF
POWERDOWN*
FORCEON
30μs
TIMER
R
-2.7V
INVALID
INVALID DEASSERTED IF ANY RECEIVER INPUT HAS BEEN BETWEEN +2.7V AND -2.7V
FOR LESS THAN 30μs.
Figure 3b. INVALID Functional Diagram, INVALID High
Table 2. INVALID Truth Table
RS-232 SIGNAL
PRESENT AT ANY
RECEIVER INPUT
INVALID OUTPUT
Yes
High
No
Low
peripheral transmitters are turned off, and the UART driving 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 system 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 summarize 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.
Maxim Integrated
AUTOSHDN
* POWERDOWN IS ONLY AN INTERNAL SIGNAL.
IT CONTROLS THE OPERATIONAL STATUS OF
THE TRANSMITTERS AND THE POWER SUPPLIES.
Figure 3d. Power-Down Logic
When shut down, the device’s charge pumps turn off,
V+ is pulled to VCC, V- is pulled to ground, the transmitter 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.
INVALID HIGH
+2.7V
RECEIVER INPUT LEVELS
R_IN
INDETERMINATE
+0.3V
0
INVALID LOW
-0.3V
INDETERMINATE
-2.7V
INVALID HIGH
Figure 4a. Receiver Positive/Negative Thresholds for INVALID
11
MAX3224E/MAX3225E/
MAX3226E/MAX3227E/MAX3244E/MAX3245E
±15kV ESD-Protected, 1µA, 1Mbps 3.0V to 5.5V,
RS-232 Transceivers with AutoShutdown Plus
RECEIVER
INPUTS
INVALID
} REGION
TRANSMITTER
INPUTS
TRANSMITTER
OUTPUTS
INVALID
OUTPUT
VCC
tINVL
0
tINVH
tAUTOSHDN
tAUTOSHDN
tWU
tWU
*VCC
READY
0
V+
VCC
0
V-
*MAX3224E–MAX3227E
Figure 4b. AutoShutdown Plus, INVALID, and READY Timing Diagram
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.
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
POWERMANAGEMENT
UNIT
MASTER SHDN LINE
0.1μF
1MΩ
FORCEOFF FORCEON
MAX3224E
MAX3225E
MAX3226E
MAX3227E
MAX3244E
MAX3245E
±15kV ESD Protection
As with all Maxim devices, ESD-protection structures are
incorporated on all pins to protect against electrostatic
12
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
RC 1MΩ
CHARGE-CURRENT
LIMIT RESISTOR
HIGHVOLTAGE
DC
SOURCE
Cs
100pF
RC 50MΩ to 100MΩ
RD 1500Ω
DISCHARGE
RESISTANCE
CHARGE CURRENT
LIMIT RESISTOR
DEVICE
UNDER
TEST
STORAGE
CAPACITOR
Figure 6a. Human Body ESD Test Model
HIGHVOLTAGE
DC
SOURCE
Cs
150pF
RD 330Ω
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
DEVICE
UNDER
TEST
Figure 7a. IEC 1000-4-2 ESD Test Model
I
IP 100%
90%
Ir
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
100%
90%
AMPERES
I PEAK
36.8%
10%
0
0
tRL
TIME
tDL
CURRENT WAVEFORM
10%
Figure 6b. Human Body Current Waveform
t r = 0.7ns to 1ns
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.
Maxim Integrated
t
30ns
60ns
Figure 7b. IEC 1000-4-2 ESD Generator Current Waveform
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 discharged into a low impedance. This model consists of
a 100pF capacitor charged to the ESD voltage of interest, which is then discharged into the test device
through a 1.5kΩ resistor.
13
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 performance 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, without 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 withstand 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 resistance. Its objective is to emulate the stress caused by
contact that occurs with handling and assembly during
manufacturing. Of course, all pins require this protection 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
Table 3. Required Minimum Capacitance
Values
14
VCC
(V)
C1, CBYPASS
(µF)
C2, C3, C4
(µF)
3.0 to 3.6
0.22
0.22
3.15 to 3.6
0.1
0.1
4.5 to 5.5
0.047
0.33
3.0 to 5.5
0.22
1
5V/div
0
FORCEON = FORCEOFF
T1OUT
2V/div
0
5V/div
0
T2OUT
VCC = 3.3V
C1–C4 = 0.1μF
READY
5μs/div
Figure 8. Transmitter Outputs when Exiting Shutdown or
Powering Up
can be used. The charge pump requires 0.1µF capacitors for 3.3V operation. For other supply voltages, see
Table 3 for required capacitor values. Do not use values 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 capacitors with a larger nominal value. The capacitor’s equivalent 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 powersupply noise, use a capacitor of the same value as
charge-pump capacitor C1. Connect bypass capacitors 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 transmitter outputs are shown going to opposite RS-232 levels (one transmitter input is high, the other is low). Each
Maxim Integrated
MAX3224E/MAX3225E/
MAX3226E/MAX3227E/MAX3244E/MAX3245E
±15kV ESD-Protected, 1µA, 1Mbps 3.0V to 5.5V,
RS-232 Transceivers with AutoShutdown Plus
transmitter is loaded with 3kΩ in parallel with 1000pF.
The transmitter outputs display no ringing or undesirable transients as they come out of shutdown. Note that
the transmitters are enabled only when the magnitude
of V- exceeds approximately -3V.
5V/div
T1IN
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 loopback 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 driven 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.
5V/div
T1OUT
5V/div
R1OUT
VCC = 3.3V
2μs/div
Figure 10. MAX3224E/MAX3226E/MAX3244E Loopback Test
Result at 120kbps
T1IN
5V/div
T1OUT
5V/div
VCC
5V/div
R1OUT
CBYPASS
VCC = 3.3V
VCC
C1+
C1
C1C2+
C2
C2-
MAX3224E
MAX3225E
MAX3226E
MAX3227E
MAX3244E
MAX3245E
C4
5kΩ
FORCEON
GND
Figure 11. MAX3224E/MAX3226E/MAX3244E Loopback Test
Result at 250kbps
V-
R_ IN
R_ OUT
FORCEOFF
C3*
T_ OUT
T_ IN
VCC
2μs/div
V+
T1IN
5V/div
T1OUT
5V/div
1000pF
5V/div
R1OUT
VCC = 3.3V
200ns/div
*C3 CAN BE RETURNED TO VCC OR GND.
Figure 9. Loopback Test Circuit
Maxim Integrated
Figure 12. MAX3225E/MAX3227E/MAX3245E Loopback Test
Result at 1Mbps
15
MAX3224E/MAX3225E/
MAX3226E/MAX3227E/MAX3244E/MAX3245E
±15kV ESD-Protected, 1µA, 1Mbps 3.0V to 5.5V,
RS-232 Transceivers with AutoShutdown Plus
+3.3V
26
0.1μF
28
C1
0.1μF
24
1
C2
0.1μF
2
LOGIC
INPUTS
VCC
27
C1+
V+
C3
0.1μF
C1C2+
MAX3244E
MAX3245E
COMPUTER SERIAL PORT
3
V-
C4
0.1μF
C2-
14
T1IN
T1OUT
9
+V
13
T2IN
T2OUT
10
+V
12
T3IN
T3OUT
11
-V
20
R2OUTB
19
R1OUT
GND
R1IN
4
R2IN
5
R3IN
6
R4IN
7
R5IN
8
Tx
5kΩ
18
R2OUT
LOGIC
OUTPUTS
5kΩ
17
R3OUT
RS-232
INPUTS
5kΩ
16
R4OUT
5kΩ
15
23
VCC
TO POWERMANAGEMENT
UNIT
22
21
R5OUT
SERIAL
MOUSE
5kΩ
FORCEON
FORCEOFF
INVALID
GND
25
Figure 13a. Mouse Driver Test Circuit
16
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
TRANSMITTER OUTPUT VOLTAGE (V)
5
4
3
VOUT+
VCC = 3.0V
2
1
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.
MAX2343E-FIG15
6
VOUT+
0
-1
-2
VCC
-3
-4
VOUTVOUT-
-5
-6
0
1
2
3
4
5
6
7
8
9
10
Interconnection with 3V and 5V Logic
LOAD CURRENT PER TRANSMITTER (mA)
The MAX3224E–MAX3227E/MAX3244E/MAX3245E can
directly interface with various 5V logic families, including ACT and HCT CMOS. See Table 4 for more information on possible combinations of interconnections.
Figure 13b. MAX324_E Transmitter Output Voltage vs. Load
Current per Transmitter
Table 5 lists other Maxim ESD-powered transceivers.
Table 4. Logic Family Compatibility with Various Supply Voltages
SYSTEM
POWER-SUPPLY
VOLTAGE (V)
VCC SUPPLY
VOLTAGE
(V)
3.3
3.3
5
5
5
3.3
COMPATIBILITY
Compatible with all CMOS families
Compatible with all TTL and CMOS families
Compatible with ACT and HCT CMOS, and with AC, HC, or CD4000 CMOS
Table 5. ±15kV ESD-Protected, 3.0V to 5.5V Powered RS-232 Transceivers from Maxim
PART
SUPPLY
VOLTAGE
RANGE
(V)
MAX3241E
+3.0 to +5.5
3/5
300
—
—
±15
±8
±15
250
MAX3243E
+3.0 to +5.5
3/5
1
—
Yes
±15
±8
±15
250
MAX3244E
+3.0 to +5.5
3/5
1
Yes
—
±15
±8
±15
250
MAX3245E
+3.0 to +5.5
3/5
1
Yes
—
±15
±8
±15
1Mbps
MAX3232E
+3.0 to +5.5
2/2
300
—
—
±15
±8
±15
250
MAX3222E
+3.0 to +5.5
2/2
300
—
—
±15
±8
±15
250
MAX3223E
+3.0 to +5.5
2/2
1
—
Yes
±15
±8
±15
250
MAX3224E
+3.0 to +5.5
2/2
1
Yes
—
±15
±8
±15
250
MAX3225E
+3.0 to +5.5
2/2
1
Yes
—
±15
±8
±15
1Mbps
MAX3221E
+3.0 to +5.5
1/1
1
—
Yes
±15
±8
±15
250
MAX3226E
+3.0 to +5.5
1/1
1
Yes
—
±15
±8
±15
250
MAX3227E
+3.0 to +5.5
1/1
1
Yes
—
±15
±8
±15
1Mbps
Maxim Integrated
NO. SUPPLY
AutoAutoOF CURRENT Shutdown
Shutdown
Tx/Rx
Plus
(µA)
Human
Body
Model
(kV)
IEC 1000-4-2 IEC 1000-4-2
GUARANTEED
Contact
Air-Gap
DATA RATE
Discharge
Discharge
(kbps)
(kV)
(kV)
17
MAX3224E/MAX3225E/
MAX3226E/MAX3227E/MAX3244E/MAX3245E
±15kV ESD-Protected, 1µA, 1Mbps 3.0V to 5.5V,
RS-232 Transceivers with AutoShutdown Plus
___________________________________________________Typical Operating Circuits
+3.3V
+3.3V
15
0.1μF
CBYPASS
2 C1+
C1
0.1μF
4
5
C2
0.1μF
6
C1C2+
3
V+
MAX3226E*
MAX3227E
V-
9 R1OUT
C3
0.1μF
C1
0.1μF
C4
0.1μF
C2
0.1μF
7
C2-
11 T1IN
12
READY
AutoShutdown
Plus
24
1
2
27
V+
C3
0.1μF
C1C2+
MAX3244E***
MAX3245E
V-
3
C4
0.1μF
C2-
14 T1IN
T1OUT 9
R1IN 8
13 T2IN
T2OUT 10
12 T3IN
T3OUT 11
INVALID 10
FORCEOFF 16
FORCEON
28 C1+
VCC
T1OUT 13
5kΩ
1
26
CBYPASS
0.1μF
VCC
GND
TO POWERMANAGEMENT
UNIT
VCC
22 FORCEOFF
23 FORCEON
AutoShutdown
Plus
INVALID 21
20 R2OUTB
14
19 R1OUT
R1IN 4
18 R2OUT
R2IN
17 R3OUT
R3IN 6
16 R4OUT
R4IN 7
15 R5OUT
R5IN 8
+3.3V
CBYPASS
C1
0.1μF
2 C1+
4 C15
C2
0.1μF
TTL/CMOS
INPUTS
19
0.1μF
6
C2+
VCC
3
V+
MAX3224E**
MAX3225E
V-
C3
0.1μF
7
C4
0.1μF
C2-
13 T1IN
T1OUT 17
12 T2IN
T2OUT 8
RS-232
OUTPUTS
GND
R1IN 16
15 R1OUT
TTL/CMOS
OUTPUTS
RS-232
INPUTS
5kΩ
R2IN
10 R2OUT
5
25
9
5kΩ
1
14
READY
AutoShutdown
Plus
INVALID 11
FORCEOFF 20
FORCEON
GND
TO POWERMANAGEMENT
UNIT
VCC
*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.
18
18
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 Configurations
+
+
+
READY 1
READY 1
16 FORCEOFF
20 FORCEOFF
C2+ 1
28 C1+
C1+ 2
15 VCC
C1+ 2
19 VCC
C2- 2
27 V+
V+ 3
14 GND
V+ 3
18 GND
V- 3
26 VCC
17 T1OUT
R1IN 4
25 GND
16 R1IN
R2IN 5
15 R1OUT
R3IN 6
14 FORCEON
R4IN 7
22 FORCEOFF
8
13 T1IN
R5IN 8
21 INVALID
R2IN 9
12 T2IN
T1OUT 9
20 R2OUTB
11 INVALID
T2OUT 10
19 R1OUT
T3OUT 11
18 R2OUT
T3IN 12
17 R3OUT
V- 7
12 FORCEON
11 T1IN
C2- 6
V- 7
10 INVALID
T2OUT
9 R1OUT
R1IN 8
MAX3224E
MAX3225E
SSOP/TSSOP
R1IN
R1OUT
FORCEON
T1IN
TOP VIEW
T1OUT
R2OUT 10
15
14
13
12
11
DIP/SSOP/TSSOP
GND 16
10
T2IN
VCC 17
9
INVALID
8
R2OUT
7
R2IN
6
T2OUT
FORCEOFF 18
MAX3224E
MAX3225E
READY 19
24 C1-
MAX3244E
MAX3245E
23 FORCEON
T2IN 13
16 R4OUT
T1IN 14
15 R5OUT
SO/SSOP/TSSOP
TOP VIEW
C2+
N.C.
C1+
V+
VCC
N.C.
C2- 6
C1- 4
C2+ 5
N.C.
C2+ 5
13 T1OUT
VC2-
MAX3226E
MAX3227E
C1- 4
36 35 34 33 32 31 30 29 28
*EP
V+ 20
1
2
3
4
5
C1+
C1-
C2+
C2-
V-
+
12
11
10
FORCEON
T1OUT
VCC
TOP VIEW
GND
TQFN
+
20
GND
C1FORCEON
FORCEOFF
INVALID
N.C.
R2OUTB
R1OUT
19
R2OUT
R1IN
R2IN
1
27
2
26
R3IN
R4IN
R5IN
N.C.
3
25
T1OUT
T2OUT
T3OUT
7
4
24
5
23
MAX3245E
6
22
21
8
*EP
9
9
READY 14
7
INVALID
6
R1OUT
5
R1IN
MAX3226E
MAX3227E
V+ 15
C1+ 16
*EP
N.C.
T1IN
R3OUT
8
N.C.
FORCEOFF 13
T3IN
T2IN
T1IN
N.C.
R5OUT
R4OUT
10 11 12 13 14 15 16 17 18
TQFN
C2+
3
4
V-
2
C2-
1
C1-
+
TQFN
Maxim Integrated
*CONNECT EP TO GND.
19
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)
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
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.
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE
NO.
LAND
PATTERN NO.
16 SSOP
A16+2
21-0056
90-0106
MAX3226ECTE+
0°C to +70°C
16 TQFN-EP*
16 TSSOP
U16+1
21-0066
90-0117
MAX3226ECUE+
0°C to +70°C
16 TSSOP
16 TQFN-EP
T1655+2
21-0140
90-0072
MAX3226ECAE+
0°C to +70°C
16 SSOP
20 DIP
P20+3
21-0043
—
MAX3226EEAE+
-40°C to +85°C
16 SSOP
20 SSOP
A20+1
21-0056
90-0094
MAX3226EETE+
-40°C to +85°C
16 TQFN-EP*
20 TSSOP
U20+2
21-0066
90-0116
MAX3226EEUE+
-40°C to +85°C
16 TSSOP
20 TQFN-EP
T2055+5
21-0140
90-0010
MAX3226EAAE+
-40°C to +125°C
16 SSOP
28 Wide SO
W28+6
21-0042
90-0109
MAX3227ECAE+
0°C to +70°C
16 SSOP
28 SSOP
A28+1
21-0056
90-0095
MAX3227ECTE+
0°C to +70°C
16 TQFN-EP*
28 TSSOP
U28+2
21-0066
90-0171
MAX3227ECUE+
0°C to +70°C
16 TSSOP
T3666+3
21-0141
90-0050
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
MAX3244ECWI+
0°C to +70°C
28 Wide SO
MAX3244ECAI+
0°C to +70°C
28 SSOP
36 TQFN
16 SSOP
MAX3244ECUI+
0°C to +70°C
MAX3244EEWI+
-40°C to +85°C
28 Wide SO
28 TSSOP
MAX3244EEAI+
-40°C to +85°C
28 SSOP
MAX3244EEUI+
-40°C to +85°C
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*
28 TSSOP
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
/V denotes an automotive qualified part.
20
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
10
3/11
DESCRIPTION
Added an automotive qualified part to the Ordering Information; changed all the
parts listed in the Ordering Information to lead free
PAGES
CHANGED
1, 20
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.
Maxim Integrated 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-1000
© Maxim Integrated
21
The Maxim logo and Maxim Integrated are trademarks of Maxim Integrated Products, Inc.
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