MAX3222E [MAXIM]
【15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V, Up to 1Mbps, True RS-232 Transceivers; ± 15kV ESD保护，低至10nA的， 3.0V至5.5V ，最高可达1Mbps，真RS- 232收发器
| 型号： | MAX3222E |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | 【15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V, Up to 1Mbps, True RS-232 Transceivers |
| 文件： | 总20页 (文件大小：299K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
19-1298; Rev 3a; 1/00
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
________________General Description
____________________________Features
o ESD Protection for RS-232 I/O Pins
(MAX3222E/MAX3232E/MAX3241E)
15kV—Human Body Model
The MAX3222E/MAX3232E/MAX3237E/MAX3241E are
3V-powered EIA/TIA-232 and V.28/V.24 communications
interfaces with low power requirements, high data-
rate capabilities, and enhanced electrostatic discharge
(ESD) protection. All transmitter outputs and receiver
inputs are protected to 1ꢀ5V using IEꢁ 1ꢂꢂꢂ-4-2 Air-
Gap Discharge, 85V using IEꢁ 1ꢂꢂꢂ-4-2 ꢁontact Dis-
charge, and 1ꢀ5V using the ꢃuman ꢄodꢅ Model. The
MAX3237E’s logic and receiver I/O pins are protected to
the above standards, while the transmitter output pins are
protected to 1ꢀ5V using the ꢃuman ꢄodꢅ Model.
8kV—IEC 1000-4-2, Contact Discharge
15kV—IEC 1000-4-2, Air-Gap Discharge
o ESD Protection for All Logic and Receiver I/O
Pins (MAX3237E)
15kV—Human Body Model
8kV—IEC 1000-4-2, Contact Discharge
15kV—IEC 1000-4-2, Air-Gap Discharge
o ESD Protection for Transmitter Output Pins
(MAX3237E)
15kV—Human Body Model
o Guaranteed Data Rate
250kbps (MAX3222E/MAX3232E/MAX3241E
and MAX3237E, normal operation)
1Mbps (MAX3237E, MegaBaud operation)
o Latchup Free
o Low-Power Shutdown with Receivers Active
1µA (MAX3222E/MAX3241E)
The transceivers have a proprietarꢅ low-dropout transmit-
ter output stage, delivering true RS-232 performance from
a +3.ꢂV to +ꢀ.ꢀV supplꢅ with a dual charge pump. The
charge pump requires onlꢅ four small ꢂ.1µF capacitors
for operation from a +3.3V supplꢅ. Each device is guaran-
teed to run at data rates of 2ꢀꢂ5bps while maintaining RS-
232 output levels. The MAX3237E is guaranteed to run at
data rates of 2ꢀꢂ5bps in the normal operating mode and
1Mbps in the Megaꢄaud™ operating mode while main-
taining RS-232-compliant output levels.
The MAX3222E/MAX3232E have two receivers and two
drivers. The MAX3222E features a 1µA shutdown mode
that reduces power consumption and extends batterꢅ
life in portable sꢅstems. Its receivers can remain active
in shutdown mode, allowing external devices such as
modems to be monitored using onlꢅ 1µA supplꢅ current.
ꢄoth the MAX3222E and MAX3232E are pin, pac5age,
and functionallꢅ compatible with the industrꢅ-standard
MAX242 and MAX232, respectivelꢅ.
The MAX3241E is a complete serial port (three drivers/five
receivers) designed for noteboo5 and subnoteboo5 com-
puters. The MAX3237E (five drivers/three receivers) is ideal
for peripheral applications that require fast data transfer.
ꢄoth devices feature a shutdown mode in which all
receivers can remain active while using a supplꢅ cur-
rent of onlꢅ 1µA (MAX3241E) or 1ꢂnA (MAX3237E). The
MAX3237E/MAX3241E have additional receiver outputs
that alwaꢅs remain active.
The MAX3222E and MAX3232E are available in space-
saving SO, SSOP, and TSSOP pac5ages. The MAX3241E
is available in SO and SSOP pac5ages. The MAX3237E is
available in an SSOP pac5age.
10nA (MAX3237E)
o Flow-Through Pinout (MAX3237E)
o Guaranteed Mouse Driveability (MAX3241E)
o Meets EIA/TIA-232 Specifications Down to 3.0V
_______________Ordering Information
PART
TEMP. RANGE
ꢂ°ꢁ to +7ꢂ°ꢁ
ꢂ°ꢁ to +7ꢂ°ꢁ
PIN-PACKAGE
2ꢂ TSSOP
MAX3222EꢁUP
MAX3222EꢁAP
2ꢂ SSOP
Ordering Information continued at end of data sheet.
___________________________Selector Guide
NO. OF
DRIVERS/
RECEIVERS SHUTDOWN
LOW-
POWER
GUARANTEED
DATA RATE
(kbps)
PART
✔
MAX3222E
MAX3232E
2/2
2ꢀꢂ
2ꢀꢂ
2/2
—
MAX3237E
(Normal)
✔
ꢀ/3
2ꢀꢂ
MAX3237E
(Megaꢄaud)
________________________Applications
✔
✔
ꢀ/3
3/ꢀ
1M
Noteboo5s, Subnoteboo5s,
and Palmtop ꢁomputers
Smart Phones
XDSL Modems
MAX3241E
2ꢀꢂ
ꢄatterꢅ-Powered Equipment Printers
Pin Configurations appear at end of data sheet.
Typical Operating Circuits appear at end of data sheet.
ꢁell-Phone Data ꢁables
ꢁell Phones
MegaBaud is a trademark of Maxim Integrated Products.
†
Covered by U.S. Patent numbers 4,636,930; 4,679,134; 4,777,577; 4,797,899; 4,809,152; 4,897,774; 4,999,761; and other patents pending.
________________________________________________________________ Maxim Integrated Products
1
For free samples and the latest literature, visit www.maxim-ic.com or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
ABSOLUTE MAXIMUM RATINGS
ꢁꢁ
V
to GND..............................................................-ꢂ.3V to +6V
16-Pin Wide SO (derate 9.ꢀ2mW/°ꢁ above +7ꢂ°ꢁ) .....762mW
18-Pin Wide SO (derate 9.ꢀ2mW/°ꢁ above +7ꢂ°ꢁ) .....762mW
18-Pin PDIP (derate 11.11mW/°ꢁ above +7ꢂ°ꢁ)..........889mW
2ꢂ-Pin TSSOP (derate 7.ꢂmW/°ꢁ above +7ꢂ°ꢁ) ..........ꢀꢀ9mW
2ꢂ-Pin SSOP (derate 8.ꢂꢂmW/°ꢁ above +7ꢂ°ꢁ) ..........64ꢂmW
28-Pin SSOP (derate 9.ꢀ2mW/°ꢁ above +7ꢂ°ꢁ) ..........762mW
28-Pin Wide SO (derate 12.ꢀꢂmW/°ꢁ above +7ꢂ°ꢁ).............1W
Operating Temperature Ranges
V+ to GND (Note 1)..................................................-ꢂ.3V to +7V
V- to GND (Note 1) ...................................................+ꢂ.3V to -7V
V+ + |V-| (Note 1).................................................................+13V
Input Voltages
T_IN, EN, SHDN, MꢄAUD to GND ........................-ꢂ.3V to +6V
R_IN to GND ..................................................................... 2ꢀV
Output Voltages
T_OUT to GND............................................................... 13.2V
MAX32_ _Eꢁ_ _ ...................................................ꢂ°ꢁ to +7ꢂ°ꢁ
MAX32_ _EE_ _.................................................-4ꢂ°ꢁ to +8ꢀ°ꢁ
Storage Temperature Range.............................-6ꢀ°ꢁ to +1ꢀꢂ°ꢁ
Lead Temperature (soldering, 1ꢂs) .................................+3ꢂꢂ°ꢁ
R_OUT, R_OUTꢄ (MAX3241E)................-ꢂ.3V to (V
+ ꢂ.3V)
ꢁꢁ
Short-ꢁircuit Duration, T_OUT to GND.......................ꢁontinuous
ꢁontinuous Power Dissipation (T = +7ꢂ°ꢁ)
A
16-Pin SSOP (derate 7.14mW/°ꢁ above +7ꢂ°ꢁ) ..........ꢀ71mW
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
(V
= +3.ꢂV to +ꢀ.ꢀV, ꢁ1–ꢁ4 = ꢂ.1µF, T = T
A
to T
, unless otherwise noted. Tꢅpical values are at T = +2ꢀ°ꢁ.) (Note 2)
MAX A
ꢁꢁ
MIN
PARAMETER
CONDITIONS
= +3.3V or +ꢀ.ꢂV, T = +2ꢀ°ꢁ)
MIN
TYP
MAX
UNITS
DC CHARACTERISTICS (V
ꢁꢁ
A
MAX3222E, MAX3232E,
MAX3241E
ꢂ.3
1
Supplꢅ ꢁurrent
mA
SHDN = V , no load
ꢁꢁ
MAX3237E
ꢂ.ꢀ
1
2.ꢂ
1ꢂ
µA
nA
SHDN = GND
Shutdown Supplꢅ ꢁurrent
1ꢂ
3ꢂꢂ
SHDN = R_IN = GND, T_IN = GND or V (MAX3237E)
ꢁꢁ
LOGIC INPUTS
Input Logic Low
ꢂ.8
V
V
V
T_IN, EN, SHDN, MꢄAUD
V
V
= 3.3V
= ꢀ.ꢂV
2.ꢂ
2.4
ꢁꢁ
Input Logic ꢃigh
T_IN, EN, SHDN, MꢄAUD
ꢁꢁ
Transmitter Input ꢃꢅsteresis
ꢂ.ꢀ
ꢂ.ꢂ1
9
MAX3222E, MAX3232E,
MAX3241E
1
T_IN, EN, SHDN
Input Lea5age ꢁurrent
µA
MAX3237E (Note 3)
18
T_IN, SHDN, MꢄAUD
RECEIVER OUTPUTS
R_OUT (MAX3222E/MAX3237E/MAX3241E), EN = V
receivers disabled
,
ꢁꢁ
Output Lea5age ꢁurrent
ꢂ.ꢂꢀ
1ꢂ
µA
V
I
I
= 1.6mA (MAX3222E/MAX3232E/MAX3241E)
= 1.ꢂmA (MAX3237E)
ꢂ.4
ꢂ.4
OUT
Output Voltage Low
Output Voltage ꢃigh
OUT
V
ꢂ.6
-
V
ꢁꢁ
-
ꢁꢁ
I
= -1.ꢂmA
V
OUT
ꢂ.1
RECEIVER INPUTS
Input Voltage Range
-2ꢀ
ꢂ.6
ꢂ.8
+2ꢀ
V
V
V
V
= 3.3V
= ꢀ.ꢂV
1.1
1.ꢀ
ꢁꢁ
Input Threshold Low
T = +2ꢀ°ꢁ
A
ꢁꢁ
2
_______________________________________________________________________________________
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
ELECTRICAL CHARACTERISTICS (continued)
(V
= +3.ꢂV to +ꢀ.ꢀV, ꢁ1–ꢁ4 = ꢂ.1µF, T = T
A
to T
, unless otherwise noted. Tꢅpical values are at T = +2ꢀ°ꢁ.) (Note 2)
MAX A
ꢁꢁ
MIN
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
RECEIVER INPUTS
V
V
= 3.3V
= ꢀ.ꢂV
1.ꢀ
2.ꢂ
ꢂ.ꢀ
ꢀ
2.4
2.4
ꢁꢁ
Input Threshold ꢃigh
T = +2ꢀ°ꢁ
V
A
ꢁꢁ
Input ꢃꢅsteresis
V
Input Resistance
T = +2ꢀ°ꢁ
A
3
7
5Ω
TRANSMITTER OUTPUTS
Output Voltage Swing
Output Resistance
All transmitter outputs loaded with 35Ω to ground
ꢀ
ꢀ.4
V
Ω
V
ꢁꢁ
= ꢂ, transmitter output = 2V
3ꢂꢂ
ꢀꢂ5
Output Short-ꢁircuit ꢁurrent
6ꢂ
2ꢀ
mA
V
= ꢂ or 3V to ꢀ.ꢀV, V
= 12V, transmitters disabled
ꢁꢁ
OUT
Output Lea5age ꢁurrent
µA
V
(MAX3222E/MAX3232E/MAX3241E)
MOUSE DRIVEABILITY (MAX3241E)
T1IN = T2IN = GND, T3IN = V , T3OUT loaded with 35Ω
to GND, T1OUT and T2OUT loaded with 2.ꢀmA each
ꢁꢁ
Transmitter Output Voltage
ꢀ
ESD PROTECTION
ꢃuman ꢄodꢅ Model
1ꢀ
1ꢀ
8
R_IN, T_OUT
IEꢁ 1ꢂꢂꢂ-4-2 Air-Gap Discharge (except MAX3237E)
IEꢁ 1ꢂꢂꢂ-4-2 ꢁontact Discharge (except MAX3237E)
ꢃuman ꢄodꢅ Model
5V
5V
1ꢀ
1ꢀ
8
T_IN, R_IN, R_OUT, EN, SHDN,
MꢄAUD
MAX3237E
IEꢁ 1ꢂꢂꢂ-4-2 Air-Gap Discharge
IEꢁ 1ꢂꢂꢂ-4-2 ꢁontact Discharge
TIMING CHARACTERISTICS—MAX3222E/MAX3232E/MAX3241E
(V
= +3.ꢂV to +ꢀ.ꢀV, ꢁ1–ꢁ4 = ꢂ.1µF, T = T
to T
, unless otherwise noted. Tꢅpical values are at T = +2ꢀ°ꢁ.) (Note 2)
MAX A
ꢁꢁ
A
MIN
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
R = 35Ω, ꢁ = 1ꢂꢂꢂpF,
L
L
Maximum Data Rate
2ꢀꢂ
5bps
one transmitter switching
t
t
ꢂ.1ꢀ
ꢂ.1ꢀ
2ꢂꢂ
2ꢂꢂ
1ꢂꢂ
ꢀꢂ
PꢃL
Receiver input to receiver output,
ꢁ = 1ꢀꢂpF
L
Receiver Propagation Delaꢅ
µs
PLꢃ
Receiver Output Enable Time
Receiver Output Disable Time
Transmitter S5ew
Normal operation (except MAX3232E)
Normal operation (except MAX3232E)
(Note 4)
ns
ns
ns
ns
t
t
- t
PꢃL PLꢃ
Receiver S5ew
- t
PꢃL PLꢃ
V
= 3.3V,
= +2ꢀ°ꢁ,
ꢁꢁ
ꢁ = 1ꢀꢂpF to
L
1ꢂꢂꢂpF
6
4
3ꢂ
3ꢂ
T
A
Transition-Region Slew Rate
R = 35Ω to 75Ω,
measured from +3V
to -3V or -3V to +3V
V/µs
L
ꢁ = 1ꢀꢂpF to
L
2ꢀꢂꢂpF
Note 2: MAX3222E/MAX3232E/MAX3241E: ꢁ1–ꢁ4 = ꢂ.1µF tested at 3.3V 1ꢂ0% ꢁ1 = ꢂ.ꢂ47µF, ꢁ2–ꢁ4 = ꢂ.33µF tested at ꢀ.ꢂV
1ꢂ0. MAX3237E: ꢁ1–ꢁ4 = ꢂ.1µF, tested at 3.3V ꢀ0% ꢁ1–ꢁ4 = ꢂ.22µF tested at 3.3V 1ꢂ0% ꢁ1 = ꢂ.ꢂ47µF, ꢁ2–ꢁ4 =
ꢂ.33µF tested at ꢀ.ꢂV 1ꢂ0.
Note 3: The MAX3237E logic inputs have an active positive feedbac5 resistor. The input current goes to zero when the inputs are at
the supplꢅ rails.
Note 4: Transmitter s5ew is measured at the transmitter zero crosspoints.
_______________________________________________________________________________________
3
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
TIMING CHARACTERISTICS—MAX3237E
(V
= +3.ꢂV to +ꢀ.ꢀV, ꢁ1–ꢁ4 = ꢂ.1µF, T = T
A
to T
, unless otherwise noted. Tꢅpical values are at T = +2ꢀ°ꢁ.) (Note 2)
MAX A
ꢁꢁ
MIN
PARAMETER
CONDITIONS
R = 35Ω, ꢁ = 1ꢂꢂꢂpF, one transmitter switching,
MIN
TYP
MAX
UNITS
L
L
2ꢀꢂ
MꢄAUD = GND
V
= 3.ꢂV to 4.ꢀV, R = 35Ω, ꢁ = 2ꢀꢂpF,
ꢁꢁ
L
L
Maximum Data Rate
1ꢂꢂꢂ
1ꢂꢂꢂ
5bps
one transmitter switching, MꢄAUD = V
ꢁꢁ
V
= 4.ꢀV to ꢀ.ꢀV, R = 35Ω, ꢁ = 1ꢂꢂꢂpF,
L L
ꢁꢁ
one transmitter switching, MꢄAUD = V
ꢁꢁ
t
t
ꢂ.1ꢀ
ꢂ.1ꢀ
2.6
PꢃL
Receiver Propagation Delaꢅ
R_IN to R_OUT, ꢁ = 1ꢀꢂpF
µs
L
PLꢃ
Receiver Output Enable Time Normal operation
Receiver Output Disable Time Normal operation
µs
µs
ns
ns
ns
2.4
1ꢂꢂ
1ꢂꢂ
ꢀꢂ
| t
| t
| t
- tPLꢃ |, MꢄAUD = GND
PꢃL
PꢃL
Transmitter S5ew
Receiver S5ew
- tPLꢃ |, MꢄAUD = V
ꢁꢁ
- t
|
PꢃL PLꢃ
MꢄAUD =
GND
6
3ꢂ
ꢁ = 1ꢀꢂpF
L
V
= 3.3V, R = 35Ω to
L
to 1ꢂꢂꢂpF
ꢁꢁ
MꢄAUD =
24
1ꢀꢂ
Transition-Region Slew Rate
75Ω, +3V to -3V or -3V to
+3V, T = +2ꢀ°ꢁ
V/µs
V
ꢁꢁ
A
ꢁ = 1ꢀꢂpF to 2ꢀꢂꢂpF,
L
MꢄAUD = GND
4
3ꢂ
__________________________________________Typical Operating Characteristics
(V
= +3.3V, 2ꢀꢂ5bps data rate, ꢂ.1µF capacitors, all transmitters loaded with 35Ω and ꢁ , T = +2ꢀ°ꢁ, unless otherwise noted.)
ꢁꢁ
L
A
MAX3222E/MAX3232E
OPERATING SUPPLY CURRENT
vs. LOAD CAPACITANCE
MAX3222E/MAX3232E
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
MAX3222E/MAX3232E
SLEW RATE vs. LOAD CAPACITANCE
16
14
12
10
8
45
40
35
30
25
20
6
5
4
3
2
1
0
T1 TRANSMITTING AT 250kbps
T2 TRANSMITTING AT 15.6kbps
V
OUT+
-SLEW
+SLEW
250kbps
120kbps
T1 TRANSMITTING AT 250kbps
T2 TRANSMITTING AT 15.6kbps
-1
-2
-3
-4
-5
-6
20kbps
6
15
10
5
4
V
2
OUT-
FOR DATA RATES UP TO 250kbps
0
0
0
1000
2000
3000
4000
5000
0
1000
2000
3000
4000
5000
0
1000
2000
3000
4000
5000
LOAD CAPACITANCE (pF)
LOAD CAPACITANCE (pF)
LOAD CAPACITANCE (pF)
4
_______________________________________________________________________________________
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
Typical Operating Characteristics (continued)
(V
= +3.3V, 2ꢀꢂ5bps data rate, ꢂ.1µF capacitors, all transmitters loaded with 35Ω and ꢁ , T = +2ꢀ°ꢁ, unless otherwise noted.)
ꢁꢁ
L
A
MAX3241E
OPERATING SUPPLY CURRENT
vs. LOAD CAPACITANCE
MAX3241E
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
MAX3241E
SLEW RATE vs. LOAD CAPACITANCE
14
12
10
8
60
50
40
30
20
10
0
6
5
1 TRANSMITTER AT 250kbps
2 TRANSMITTERS AT 15.6kbps
V
OUT+
4
250kbps
3
1 TRANSMITTER AT 250kbps
2 TRANSMITTERS AT 15.6kbps
2
120kbps
1
0
6
20kbps
-1
-2
-3
-4
-5
-6
4
2
V
OUT-
0
0
1000
2000
3000
4000
5000
0
1000
2000
3000
4000
5000
0
1000
2000
3000
4000
5000
LOAD CAPACITANCE (pF)
LOAD CAPACITANCE (pF)
LOAD CAPACITANCE (pF)
MAX3237E
SLEW RATE vs. LOAD CAPACITANCE
(MBAUD = GND)
MAX3237E
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE (MBAUD = V
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
)
CC
7.5
12
6
5
1Mbps
V
+
5.0
2.5
0
10
8
OUT
4
2Mbps
1.5Mbps
SR-
SR+
3
2
1 TRANSMITTER AT FULL DATA RATE
FOR DATA RATES UP TO 250kbps
1 TRANSMITTER 250kbps
1
4 TRANSMITTERS AT 1/16 DATA RATE
6
4
3kΩ + C LOAD, EACH OUTPUT
L
4 TRANSMITTERS 15.6kbps
ALL TRANSMITTERS LOADED
0
-1
-2
-3
-4
-5
-6
WITH 3kΩ + C
-2.5
-5.0
-7.5
L
1 TRANSMITTER AT 250kbps
4 TRANSMITTERS 15.6kbps
ALL TRANSMITTERS LOADED
1.5Mbps
1Mbps
2Mbps
2
0
WITH 3kΩ + C
V
L
OUT-
0
500
1000
1500
2000
0
500
1000 1500 2000 2500 3000
LOAD CAPACITANCE (pF)
0
500 1000 1500 2000 2500 300
LOAD CAPACITANCE (pF)
LOAD CAPACITANCE (pF)
MAX3237E
MAX3237E
MAX3237E
SUPPLY CURRENT vs. LOAD CAPACITANCE
WHEN TRANSMITTING DATA (MBAUD = GND)
TRANSMITTER SKEW vs. LOAD CAPACITANCE
(MBAUD = V
SLEW RATE vs. LOAD CAPACITANCE
(MBAUD = V
)
)
CC
CC
50
100
80
60
40
20
0
70
60
50
40
30
20
250kbps
120kbps
40
30
20
10
0
-SLEW, 1Mbps
+SLEW, 1Mbps
-SLEW, 2Mbps
+SLEW, 2Mbps
20kbps
1 TRANSMITTER AT 20kbps, 120kbps, 250kbps
4 TRANSMITTERS AT 15.6kbps
ALL TRANSMITTERS LOADED
|tPLH - t
|
PHL
1 TRANSMITTER AT FULL DATA RATE
4 TRANSMITTERS AT 1/16 DATA RATE
3kΩ + C LOAD EACH OUTPUT
1 TRANSMITTER AT 500kbps
4 TRANSMITTERS AT 1/16 DATA RATE
ALL TRANSMITTERS LOADED
10
0
WITH 3kΩ + C
L
L
WITH 3kΩ + C
L
0
500
1000
1500
2000
0
500
1000 1500 2000 2500 3000
0
500
1000
1500
2000
LOAD CAPACITANCE (pF)
LOAD CAPACITANCE (pF)
LOAD CAPACITANCE (pF)
_______________________________________________________________________________________
5
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
Typical Operating Characteristics (continued)
(V
= +3.3V, 2ꢀꢂ5bps data rate, ꢂ.1µF capacitors, all transmitters loaded with 35Ω and ꢁ , T = +2ꢀ°ꢁ, unless otherwise noted.)
ꢁꢁ
L
A
MAX3237E
TRANSMITTER OUTPUT VOLTAGE vs.
SUPPLY VOLTAGE (MBAUD = GND)
MAX3237E
SUPPLY CURRENT vs.
SUPPLY VOLTAGE (MBAUD = GND)
50
40
30
6
5
V
+
OUT
4
3
2
1 TRANSMITTER 250kbps
4 TRANSMITTERS 15.6kbps
ALL TRANSMITTERS LOADED
WITH 3kΩ +1000pF
1
0
-1
-2
-3
-4
-5
-6
20
1 TRANSMITTER AT 250kbps
4 TRANSMITTERS AT 15.6kbps
ALL TRANSMITTERS LOADED
WITH 3kΩ AND 1000pF
10
0
V
OUT-
4.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
2.0
2.5
3.0
3.5
4.0
5.0
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
______________________________________________________________Pin Description
PIN
MAX3222E
MAX3232E
NAME
FUNCTION
MAX3237E
MAX3241E
TSSOP/
TSSOP/
SO/DIP
SO/DIP
SSOP
SSOP
1
2
3
4
1
—
1
—
13*
28
27
2ꢀ
23
28
27
24
Receiver Enable. Active low.
EN
ꢁ1+
V+
Positive Terminal of Voltage-Doubler
ꢁharge-Pump ꢁapacitor
2
3
4
2
3
4
2
+ꢀ.ꢀV Generated bꢅ the ꢁharge Pump
Negative Terminal of Voltage-Doubler
ꢁharge-Pump ꢁapacitor
3
ꢁ1-
Positive Terminal of Inverting ꢁharge-
Pump ꢁapacitor
ꢀ
ꢀ
4
ꢀ
1
1
ꢁ2+
Negative Terminal of Inverting
ꢁharge-Pump ꢁapacitor
6
7
6
7
ꢀ
6
6
7
3
4
2
3
ꢁ2-
V-
-ꢀ.ꢀV Generated bꢅ the ꢁharge Pump
RS-232 Transmitter Outputs
ꢀ, 6, 7,
1ꢂ, 12
8, 1ꢀ
8, 17
7, 14
8, 17
9, 1ꢂ, 11
T_OUT
9, 14
9, 16
8, 13
9, 12
9, 16
8, 9, 11
4–8
R_IN
RS-232 Receiver Inputs
1ꢂ, 13
1ꢂ, 1ꢀ
12, 1ꢀ
18, 2ꢂ, 21
1ꢀ–19
R_OUT
TTL/ꢁMOS Receiver Outputs
17*, 19*, 22*,
23*, 24*
11, 12
16
12, 13
18
1ꢂ, 11
1ꢀ
13, 14
18
12, 13, 14
2ꢀ
T_IN
GND
TTL/ꢁMOS Transmitter Inputs
Ground
2
6
_______________________________________________________________________________________
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
_________________________________________________Pin Description (continued)
PIN
MAX3222E
MAX3232E
NAME
FUNCTION
MAX3237E
MAX3241E
TSSOP/
TSSOP/
SO/DIP
SO/DIP
SSOP
SSOP
17
18
19
16
—
19
26
26
22
V
+3.ꢂV to +ꢀ.ꢀV Supplꢅ Voltage
Shutdown ꢁontrol. Active low.
ꢁꢁ
2ꢂ
—
14*
SHDN
1, 1ꢂ, 11,
2ꢂ
—
—
—
11, 14
—
—
—
—
—
1ꢀ*
16
—
—
N.ꢁ.
No ꢁonnection
Megaꢄaud ꢁontrol Input. ꢁonnect to
GND for normal operation% connect to
—
—
MꢄAUD
R_OUTꢄ
V
ꢁꢁ
for 1Mbps transmission rates.
Noninverting ꢁomplementarꢅ
Receiver Outputs. Alwaꢅs active.
—
2ꢂ, 21
*These pins have an active positive feedback resistor internal to the MAX3237E, allowing unused inputs to be left unconnected.
ance state when the device is in shutdown mode (SHDN =
_______________Detailed Description
GND). The MAX3222E/MAX3232E/MAX3237E/MAX3241E
Dual Charge-Pump Voltage Converter
The MAX3222E/MAX3232E/MAX3237E/MAX3241E’s
internal power supplꢅ consists of a regulated dual
charge pump that provides output voltages of +ꢀ.ꢀV
(doubling charge pump) and -ꢀ.ꢀV (inverting charge
permit the outputs to be driven up to 12V in shutdown.
The MAX3222E/MAX3232E/MAX3241E transmitter
inputs do not have pull-up resistors. ꢁonnect unused
inputs to GND or Vꢁꢁ. The MAX3237E transmitter
inputs have a 4ꢂꢂ5Ω active positive feedbac5 resistor,
allowing unused inputs to be left unconnected.
pump), over the 3.ꢂV to ꢀ.ꢀV V
range. The charge
ꢁꢁ
pump operates in discontinuous mode% if the output
voltages are less than ꢀ.ꢀV, the charge pump is
enabled, and if the output voltages exceed ꢀ.ꢀV, the
charge pump is disabled. Each charge pump requires
a flꢅing capacitor (ꢁ1, ꢁ2) and a reservoir capacitor
(ꢁ3, ꢁ4) to generate the V+ and V- supplies (Figure 1).
MAX3237E MegaBaud Operation
For higher-speed serial communications, the MAX3237E
features Megaꢄaud operation. In Megaꢄaud operating
mode (MꢄAUD = V ), the MAX3237E transmitters
ꢁꢁ
guarantee a 1Mbps data rate with worst-case loads of
35Ω in parallel with 2ꢀꢂpF for 3.ꢂV < V
< 4.ꢀV. For ꢀV
ꢁꢁ
RS-232 Transmitters
The transmitters are inverting level translators that con-
vert TTL/ꢁMOS-logic levels to ꢀ.ꢂV EIA/TIA-232-com-
pliant levels.
1ꢂ0 operation, the MAX3237E transmitters guarantee a
1Mbps data rate into worst-case loads of 35Ω in parallel
with 1ꢂꢂꢂpF.
RS-232 Receivers
The receivers convert RS-232 signals to ꢁMOS-logic
output levels. The MAX3222E/MAX3237E/MAX3241E
receivers have inverting three-state outputs. Drive EN
high to place the receiver(s) into a high-impedance
state. Receivers can be either active or inactive in shut-
down (Table 1).
The MAX3222E/MAX3232E/MAX3237E/MAX3241E
transmitters guarantee a 2ꢀꢂ5bps data rate with worst-
case loads of 35Ω in parallel with 1ꢂꢂꢂpF, providing
compatibilitꢅ with Pꢁ-to-Pꢁ communication software
(such as LapLin5™). Transmitters can be paralleled to
drive multiple receivers or mice.
The MAX3222E/MAX3237E/MAX3241E’s transmitters are
disabled and the outputs are forced into a high-imped-
LapLink is a trademark of Traveling Software.
_______________________________________________________________________________________
7
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
V
V
CC
CC
0.1µF
0.1µF
V
V
CC
CC
C1+
C1+
V+
V-
V+
V-
C1
C2
C1
C2
C3
C4
C3
C4
C1-
C2+
C1-
C2+
MAX3222E
MAX3232E
MAX3237E
MAX3241E
MAX3222E
MAX3232E
MAX3237E
MAX3241E
C2-
C2-
T_ OUT
R_ IN
T_ OUT
R_ IN
T_ IN
T_ IN
R_ OUT
R_ OUT
5k
5k
2500pF
150pF
3k
7k
GND
GND
MINIMUM SLEW-RATE TEST CIRCUIT
MAXIMUM SLEW-RATE TEST CIRCUIT
Figure 1. Slew-Rate Test Circuits
The complementarꢅ outputs on the MAX3237E/MAX3241E
(R_OUTꢄ) are alwaꢅs active, regardless of the state of EN
or SHDN. This allows the device to be used for ring indica-
tor applications without forward biasing other devices con-
nected to the receiver outputs. This is ideal for sꢅstems
down mode is not used. SHDN has no effect on R_OUT
or R_OUTꢄ (MAX3237E/MAX3241E).
15kV ESD Protection
As with all Maxim devices, ESD-protection structures
are incorporated to protect against electrostatic
discharges encountered during handling and assem-
blꢅ. The driver outputs and receiver inputs of the
where V
drops to ꢂ in shutdown to accommodate
ꢁꢁ
peripherals such as UARTs (Figure 2).
MAX3222E/MAX3237E/MAX3241E
Shutdown Mode
Supplꢅ current falls to less than 1µA in shutdown mode
(SHDN = low). The MAX3237E’s supplꢅ current falls to
1ꢂnA (tꢅp) when all receiver inputs are in the invalid
range (-ꢂ.3V < R_IN < +ꢂ.3). When shut down, the
device’s charge pumps are shut off, V+ is pulled down
Table 1. MAX3222E/MAX3237E/MAX3241E
Shutdown and Enable Control Truth Table
R_OUTB
T_OUT
R_OUT
(MAX3237E/
MAX3241E)
SHDN
EN
to V , V- is pulled to ground, and the transmitter
ꢁꢁ
ꢂ
ꢂ
1
1
ꢂ
1
ꢂ
1
ꢃigh-Z
ꢃigh-Z
Active
Active
Active
ꢃigh-Z
Active
ꢃigh-Z
Active
Active
Active
Active
outputs are disabled (high impedance). The time
required to recover from shutdown is tꢅpicallꢅ 1ꢂꢂµs,
as shown in Figure 3. ꢁonnect SHDN to V
if the shut-
ꢁꢁ
8
______________________________________________________________________________________
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
MAX3222E/MAX3232E/MAX3237E/MAX3241E have
extra protection against static electricitꢅ. Maxim’s engi-
neers have developed state-of-the-art structures to pro-
tect these pins against ESD of 1ꢀ5V 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 5eep wor5ing without
latchup, whereas competing RS-232 products can
latch and must be powered down to remove latchup.
Furthermore, the MAX3237E logic I/O pins also have
1ꢀ5V ESD protection. Protecting the logic I/O pins to
1ꢀ5V ma5es the MAX3237E ideal for data cable appli-
cations.
ESD protection can be tested in various waꢅs% the
transmitter outputs and receiver inputs for the
MAX3222E/MAX3232E/MAX3241E are characterized
for protection to the following limits:
V
CC
•
•
1ꢀ5V using the ꢃuman ꢄodꢅ Model
85V using the ꢁontact Discharge method specified
in IEꢁ 1ꢂꢂꢂ-4-2
PREVIOUS
RS-232
V
CC
PROTECTION
DIODE
•
1ꢀ5V using IEꢁ 1ꢂꢂꢂ-4-2’s Air-Gap Discharge
method
Rx
5k
For the MAX3237E, all logic and RS-232 I/O pins are
characterized for protection to 1ꢀ5V per the ꢃuman
ꢄodꢅ Model.
UART
Tx
GND
SHDN = GND
ESD Test Conditions
ESD performance depends on a varietꢅ of conditions.
ꢁontact Maxim for a reliabilitꢅ report that documents
test setup, test methodologꢅ, and test results.
a) OLDER RS-232: POWERED-DOWN UART DRAWS CURRENT FROM
ACTIVE RECEIVER OUTPUT IN SHUTDOWN.
Human Body Model
Figure 4a shows the ꢃuman ꢄodꢅ Model, and Figure
4b shows the current waveform it generates when dis-
charged into a low impedance. This model consists of
a 1ꢂꢂpF capacitor charged to the ESD voltage of inter-
est, which is then discharged into the test device
through a 1.ꢀ5Ω resistor.
V
CC
TO
µP
LOGIC
TRANSITION
DETECTOR
MAX3237E/MAX3241E
R1OUTB
V
CC
PROTECTION
5V/div
0
SHDN
DIODE
R1IN
Rx
R1OUT
THREE-STATED
T2OUT
EN = V
CC
5k
UART
2V/div
0
T1OUT
T1IN
Tx
GND
SHDN = GND
T1OUT
V
= 3.3V
CC
b) NEW MAX3237E/MAX3241E: EN SHUTS DOWN RECEIVER OUTPUTS
C1–C4 = 0.1µF
(EXCEPT FOR B OUTPUTS), SO NO CURRENT FLOWS TO UART IN SHUTDOWN.
B OUTPUTS INDICATE RECEIVER ACTIVITY DURING SHUTDOWN WITH EN HIGH.
40µs/div
Figure 2. Detection of RS-232 Activity when the UART and
Interface are Shut Down; Comparison of MAX3237E/
MAX3241E (b) with Previous Transceivers (a)
Figure 3. Transmitter Outputs Recovering from Shutdown or
Powering Up
_______________________________________________________________________________________
9
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
IEC 1000-4-2
The IEꢁ 1ꢂꢂꢂ-4-2 standard covers ESD testing and per-
formance of finished equipment% it does not specificallꢅ
refer to integrated circuits. The MAX3222E/MAX3232E/
MAX3237E/MAX3241E help ꢅou design equipment that
meets Level 4 (the highest level) of IEꢁ 1ꢂꢂꢂ-4-2, without
the need for additional ESD-protection components.
The Air-Gap Discharge test involves approaching the
device with a charged probe. The ꢁontact 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
2ꢂꢂpF storage capacitor and zero discharge resis-
tance. Its objective is to emulate the stress caused bꢅ
contact that occurs with handling and assemblꢅ during
manufacturing. All pins require this protection during
manufacturing, not just RS-232 inputs and outputs.
Therefore, after Pꢁ board assemblꢅ, the Machine
Model is less relevant to I/O ports.
The major difference between tests done using the
ꢃuman ꢄodꢅ Model and IEꢁ 1ꢂꢂꢂ-4-2 is higher pea5
current in IEꢁ 1ꢂꢂꢂ-4-2 because series resistance is
lower in the IEꢁ 1ꢂꢂꢂ-4-2 model. ꢃence, the ESD with-
stand voltage measured to IEꢁ 1ꢂꢂꢂ-4-2 is generallꢅ
lower than that measured using the ꢃuman ꢄodꢅ
Model. Figure ꢀa shows the IEꢁ 1ꢂꢂꢂ-4-2 model, and
Figure ꢀb shows the current waveform for the 85V IEꢁ
1ꢂꢂꢂ-4-2 Level 4 ESD ꢁontact Discharge test.
R
R
C
D
1MΩ
1500Ω
I 100%
P
90%
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
I
r
DISCHARGE
RESISTANCE
CHARGE-CURRENT
LIMIT RESISTOR
AMPERES
HIGH-
VOLTAGE
DC
DEVICE
UNDER
TEST
C
STORAGE
CAPACITOR
s
36.8%
100pF
SOURCE
10%
0
TIME
0
t
RL
t
DL
CURRENT WAVEFORM
Figure 4a. Human Body ESD Test Model
Figure 4b. Human Body Model Current Waveform
I
100%
R
R
D
330Ω
C
90%
50MΩ to 100MΩ
DISCHARGE
RESISTANCE
CHARGE-CURRENT
LIMIT RESISTOR
HIGH-
VOLTAGE
DC
DEVICE
UNDER
TEST
C
s
150pF
STORAGE
CAPACITOR
SOURCE
10%
t
t = 0.7ns to 1ns
r
30ns
60ns
Figure 5b. IEC 1000-4-2 ESD Generator Current Waveform
10 ______________________________________________________________________________________
Figure 5a. IEC 1000-4-2 ESD Test Model
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
6
Table 2. Required Minimum Capacitor
Values
5
V
4
3
OUT+
V
= 3.0V
CC
V
(V)
C1
(µF)
C2, C3, C4
(µF)
CC
2
V
V
1
OUT+
OUT-
MAX3222E/MAX3232E/MAX3241E
0
3.ꢂ to 3.6
4.ꢀ to ꢀ.ꢀ
3.ꢂ to ꢀ.ꢀ
MAX3237E
3.ꢂ to 3.6
3.1ꢀ to 3.6
4.ꢀ to ꢀ.ꢀ
3.ꢂ to ꢀ.ꢀ
ꢂ.1
ꢂ.ꢂ47
ꢂ.1
ꢂ.1
-1
-2
-3
-4
-5
-6
ꢂ.33
ꢂ.47
V
CC
1
V
OUT-
9
ꢂ.22
ꢂ.1
ꢂ.22
ꢂ.1
0
2
3
4
5
6
7
8
10
LOAD CURRENT PER TRANSMITTER (mA)
ꢂ.ꢂ47
ꢂ.22
ꢂ.33
1.ꢂ
Figure 6a. MAX3241E Transmitter Output Voltage vs. Load
Current per Transmitter
Transmitter Outputs when
Recovering from Shutdown
___________Applications Information
Capacitor Selection
The capacitor tꢅpe used for ꢁ1–ꢁ4 is not critical for
proper operation% polarized or nonpolarized capacitors
can be used. The charge pump requires ꢂ.1µF capaci-
tors for 3.3V operation. For other supplꢅ voltages, see
Table 2 for required capacitor values. Do not use val-
ues smaller than those listed in Table 2. Increasing the
capacitor values (e.g., bꢅ a factor of 2) reduces ripple
on the transmitter outputs and slightlꢅ reduces power
consumption. ꢁ2, ꢁ3, and ꢁ4 can be increased without
changing ꢁ1’s value. However, do not increase C1
without also increasing the values of C2, C3, C4,
Figure 3 shows two transmitter outputs when recover-
ing from shutdown mode. As theꢅ become active, the
two transmitter outputs are shown going to opposite
RS-232 levels (one transmitter input is high, the other is
low). Each transmitter is loaded with 35Ω in parallel with
2ꢀꢂꢂpF. The transmitter outputs displaꢅ no ringing or
undesirable transients as theꢅ come out of shutdown.
Note that the transmitters are enabled onlꢅ when the
magnitude of V- exceeds approximatelꢅ -3V.
Mouse Driveability
The MAX3241E has been specificallꢅ designed to
power serial mice while operating from low-voltage
power supplies. It has been tested with leading mouse
brands from manufacturers such as Microsoft and
Logitech. The MAX3241E successfullꢅ drove all serial
mice tested and met their respective current and volt-
age requirements. Figure 6a shows the transmitter out-
put voltages under increasing load current at 3.ꢂV.
Figure 6b shows a tꢅpical mouse connection using the
MAX3241E.
and C
to maintain the proper ratios (C1 to
BYPASS
the other capacitors).
When using the minimum required capacitor values,
ma5e sure the capacitor value does not degrade
excessivelꢅ with temperature. If in doubt, use capaci-
tors with a larger nominal value. The capacitor’s equiv-
alent series resistance (ESR), which usuallꢅ rises at low
temperatures, influences the amount of ripple on V+
and V-.
High Data Rates
The MAX3222E/MAX3232E/MAX3237E/MAX3241E
maintain the RS-232 ꢀ.ꢂV minimum transmitter output
voltage even at high data rates. Figure 7 shows a trans-
mitter loopbac5 test circuit. Figure 8 shows a loopbac5
test result at 12ꢂ5bps, and Figure 9 shows the same test
at 2ꢀꢂ5bps. For Figure 8, all transmitters were driven
simultaneouslꢅ at 12ꢂ5bps into RS-232 loads in parallel
with 1ꢂꢂꢂpF. For Figure 9, a single transmitter was driv-
en at 2ꢀꢂ5bps, and all transmitters were loaded with an
RS-232 receiver in parallel with 1ꢂꢂꢂpF.
Power-Supply Decoupling
In most circumstances, a ꢂ.1µF V
bꢅpass capacitor
ꢁꢁ
is adequate. In applications that are sensitive to power-
supplꢅ noise, use a capacitor of the same value as
charge-pump capacitor ꢁ1. ꢁonnect bꢅpass capaci-
tors as close to the Iꢁ as possible.
Operation Down to 2.7V
Transmitter outputs will meet EIA/TIA-ꢀ62 levels of
3.7V with supplꢅ voltages as low as 2.7V.
______________________________________________________________________________________ 11
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
V
= 3V
CC
to 5.5V
C
BYPASS
26
27
3
28
V
CC
C1+
C1-
V+
V-
C1
C2
C3
C4
24
COMPUTER SERIAL PORT
1
2
C2+
MAX3241E
C2-
9
T1IN
14
T1OUT
T2OUT
T3OUT
+V
+V
T2IN
10
11
13
T3IN
12
21
V
CC
-V
R1OUTB
GND
Tx
20
19
R2OUTB
R1OUT
R1IN
R2IN
R3IN
R4IN
4
5
6
5k
18
17
16
R2OUT
R3OUT
5k
5k
5k
5k
7
R4OUT
R5OUT
EN
MOUSE
15
23
R5IN
8
22
SHDN
V
CC
GND
25
Figure 6b. Mouse Driver Test Circuit
The MAX3237E maintains the RS-232 ꢀ.ꢂV minimum
transmitter output voltage at data rates up to 1Mbps.
Figure 1ꢂ shows a loopbac5 test result at 1Mbps with
Interconnection with 3V and 5V Logic
The MAX3222E/MAX3232E/MAX3237E/MAX3241E can
directlꢅ interface with various ꢀV logic families, includ-
ing AꢁT and ꢃꢁT ꢁMOS. See Table 3 for more infor-
mation on possible combinations of interconnections.
MꢄAUD = V . For Figure 1ꢂ, all transmitters were
ꢁꢁ
loaded with an RS-232 receiver in parallel with 2ꢀꢂpF.
12 ______________________________________________________________________________________
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
Table 3. Logic-Family Compatibility with
Various Supply Voltages
5V/div
5V/div
5V/div
T1IN
SYSTEM
POWER-SUPPLY
VOLTAGE
(V)
V
CC
SUPPLY
VOLTAGE
(V)
COMPATIBILITY
ꢁompatible with all
ꢁMOS families
T1OUT
R1OUT
3.3
ꢀ
3.3
ꢀ
ꢁompatible with all
TTL and ꢁMOS fami-
lies
V
= 3.3V
CC
C1–C4 = 0.1µF
ꢁompatible with AꢁT
and ꢃꢁT ꢁMOS, and
with Aꢁ, ꢃꢁ, or
2µs/div
ꢀ
3.3
Figure 8. MAX3241E Loopback Test Result at 120kbps
ꢁD4ꢂꢂꢂ ꢁMOS
5V/div
T1IN
T1OUT
R1OUT
V
CC
0.1µF
5V/div
5V/div
V
CC
C1+
V+
C3
C1
C1-
C2+
V
= 3.3V, C1–C4 = 0.1µF
CC
MAX3222E
MAX3232E
MAX3237E
MAX3241E
V-
C4
C2
2µs/div
C2-
Figure 9. MAX3241E Loopback Test Result at 250kbps
T_ OUT
R_ IN
T_ IN
R_ OUT
+5V
5k
T_IN
1000pF
0
+5V
GND
0
-5V
+5V
0
T_OUT
5kΩ + 250pF
V
= 3.3V
CC
C1–C4 = 0.1µF
R_OUT
Figure 7. Loopback Test Circuit
400ns/div
Figure 10. MAX3237E Loopback Test Result at 1000kbps
(MBAUD = V
)
CC
______________________________________________________________________________________ 13
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
Pin Configurations
TOP VIEW
N.C.
C1+
V+
1
2
N.C.
EN
C1+
V+
20
19
18
17
16
15
14
13
12
11
1
2
3
4
5
6
7
8
9
SHDN
18
17
16
15
14
13
12
11
EN
C1+
V+
1
2
SHDN
20
19
18
17
16
15
14
13
12
11
V
CC
V
CC
V
CC
GND
3
GND
GND
3
T1OUT
R1IN
C1-
4
T1OUT
R1IN
C1-
T1OUT
R1IN
R1OUT
N.C.
C1-
4
MAX3232E
MAX3222E
MAX3222E
C2+
C2-
5
C2+
C2-
C2+
C2-
5
R1OUT
T1IN
6
R1OUT
T1IN
6
V-
7
V-
V-
7
T2OUT
T2IN
8
T2IN
T2OUT
R2IN
T2OUT
T1IN
8
R2OUT
N.C.
R2IN
N.C.
9
10 R2OUT
T2IN
R2IN
9
R2OUT
10
N.C.
10
SO/DIP
TSSOP
TSSOP/SSOP
1
2
3
4
5
6
7
8
C1+
V+
V
CC
16
15
14
28
27
26
28
27
26
25
24
23
22
1
2
1
2
3
4
5
6
7
8
9
C2+
C2-
C2+
GND
C1+
V+
C1+
V+
GND
C1-
T1OUT
V
C2-
V-
3
CC
V
CC
MAX3232E
C2+
C2-
13 R1IN
12 R1OUT
11 T1IN
V-
25 C1-
4
R1IN
R2IN
R3IN
R4IN
R5IN
T1OUT
GND
C1-
T1IN
T1OUT
T2OUT
T3OUT
5
24
23
MAX3237E
MAX3241E
V-
6
T2IN
EN
10
9
T2OUT
R2IN
T2IN
7
22 T3IN
21
SHDN
R2OUT
21 R1OUTB
8
R1IN
R2IN
R1OUT
R2OUTB
R1OUT
9
20
19
20
19
R2OUT
T4IN
SSOP/SO/DIP
10
11
12
13
14
T2OUT 10
T4OUT
R3IN
18 R3OUT
T5IN
T3OUT
T3IN
18 R2OUT
17 R3OUT
16 R4OUT
11
12
13
14
17
T5OUT
EN
16 R1OUTB
T2IN
15
15
T1IN
MBAUD
R5OUT
SHDN
SSOP
SSOP/SO
14 ______________________________________________________________________________________
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
__________________________________________________Typical Operating Circuits
+3.3V
+3.3V
17
16
C
C
BYPASS
BYPASS
V
V
CC
CC
3
7
2
4
5
6
2
6
1
3
4
5
C1+
C1+
V+
V+
C1
0.1µF
C1
0.1µF
C3*
C3*
0.1µF
0.1µF
C1-
C2+
C1-
C2+
MAX3222E
MAX3232E
V-
V-
C2
0.1µF
C2
0.1µF
C4
0.1µF
C4
0.1µF
C2-
C2-
12
T1OUT
T1IN
15
8
11
T1OUT
T1IN
14
7
TTL/CMOS
INPUTS
RS-232
TTL/CMOS
INPUTS
RS-232
OUTPUTS
OUTPUTS
T2IN
T2OUT
R1IN
11
T2IN
T2OUT
R1IN
10
14
9
13 R1OUT
10 R2OUT
13
8
12 R1OUT
TTL/CMOS
OUTPUTS
TTL/CMOS
OUTPUTS
RS-232
INPUTS
5k
RS-232
INPUTS
5k
R2IN
9
R2OUT
R2IN
5k
5k
EN
1
18
SHDN
GND
16
GND
15
*C3 CAN BE RETURNED TO EITHER V OR GROUND.
CC
NOTE: PIN NUMBERS REFER TO SO/DIP PACKAGES.
SEE TABLE 2 FOR CAPACITOR SELECTION.
______________________________________________________________________________________ 15
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
_____________________________________Typical Operating Circuits (continued)
+3.3V
+3.3V
C
C
BYPASS
28
BYPASS
28
26
26
V
V
CC
CC
27
4
27
3
C1+
C1+
V+
V-
V+
C1
C3*
0.1µF
0.1µF
C3*
0.1µF
25
1
24
1
C1-
C2+
C1-
C2+
0.1µF
MAX3237E
MAX3241E
V-
C2
0.1µF
C4
0.1µF
0.1µF
0.1µF
3
2
C2-
C2-
T1IN
T1IN
T1OUT
T2OUT
T3OUT
5
6
7
T1OUT
9
24
14
13
T1
T2
T2IN
T3IN
T2IN
T2OUT 10
23
22
TTL/CMOS
INPUTS
RS-232
OUTPUTS
T3IN
12
21
11
T3OUT
R1IN
RS-232
OUTPUTS
LOGIC
T3
T4
T5
INPUTS
R1OUTB
T4IN
T5IN
T4OUT 10
19
17
R2OUTB
R1OUT
20
19
12
T5OUT
R1IN
4
5
R1OUTB
R1OUT
16
21
5k
R2OUT
R3OUT
R4OUT
R2IN
R3IN
R4IN
R5IN
18
17
16
8
9
R1
R2
R3
5k
5k
TTL/CMOS
OUTPUTS
5k
6
7
8
RS-232
INPUTS
RS-232
INPUTS
R2OUT
R3OUT
R2IN
R3IN
20
18
LOGIC
OUTPUTS
5k
5k
11
5k
5k
R5OUT
EN
15
23
15
14
MBAUD
SHDN
EN
13
22
SHDN
GND
2
GND
25
*C3 CAN BE RETURNED TO EITHER V OR GROUND.
CC
16 ______________________________________________________________________________________
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
__Ordering Information (continued)
___________________Chip Information
TRANSISTOR ꢁOUNTS:
PART
TEMP. RANGE
ꢂ°ꢁ to +7ꢂ°ꢁ
ꢂ°ꢁ to +7ꢂ°ꢁ
ꢂ°ꢁ to +7ꢂ°ꢁ
-4ꢂ°ꢁ to +8ꢀ°ꢁ
-4ꢂ°ꢁ to +8ꢀ°ꢁ
-4ꢂ°ꢁ to +8ꢀ°ꢁ
-4ꢂ°ꢁ to +8ꢀ°ꢁ
ꢂ°ꢁ to +7ꢂ°ꢁ
ꢂ°ꢁ to +7ꢂ°ꢁ
ꢂ°ꢁ to +7ꢂ°ꢁ
ꢂ°ꢁ to +7ꢂ°ꢁ
-4ꢂ°ꢁ to +8ꢀ°ꢁ
-4ꢂ°ꢁ to +8ꢀ°ꢁ
-4ꢂ°ꢁ to +8ꢀ°ꢁ
-4ꢂ°ꢁ to +8ꢀ°ꢁ
-ꢂ°ꢁ to +7ꢂ°ꢁ
-4ꢂ°ꢁ to +8ꢀ°ꢁ
ꢂ°ꢁ to +7ꢂ°ꢁ
ꢂ°ꢁ to +7ꢂ°ꢁ
-4ꢂ°ꢁ to +8ꢀ°ꢁ
-4ꢂ°ꢁ to +8ꢀ°ꢁ
PIN-PACKAGE
18 Wide SO
18 Plastic DIP
Dice*
MAX3222E/MAX3232E: 1129
MAX3237E: 211ꢂ
MAX3222EꢁWN
MAX3222EꢁPN
MAX3222Eꢁ/D
MAX3222EEUP
MAX3222EEAP
MAX3222EEWN
MAX3222EEPN
MAX3232EꢁUP
MAX3232EꢁAE
MAX3232EꢁWE
MAX3232EꢁPE
MAX3232EEUP
MAX3232EEAE
MAX3232EEWE
MAX3232EEPE
MAX3237EꢁAI
MAX3237EEAI
MAX3241EꢁAI
MAX3241EꢁWI
MAX3241EEAI
MAX3241EEWI
MAX3241E: 133ꢀ
2ꢂ TSSOP
2ꢂ SSOP
18 Wide SO
18 Plastic DIP
2ꢂ TSSOP
16 SSOP
16 Wide SO
16 Plastic DIP
2ꢂ TSSOP
16 SSOP
16 Wide SO
16 Plastic DIP
28 SSOP
28 SSOP
28 SSOP
28 Wide SO
28 SSOP
28 Wide SO
*Dice are tested at T = +25°C, DC parameters only.
A
______________________________________________________________________________________ 17
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
________________________________________________________Package Information
18 ______________________________________________________________________________________
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
___________________________________________Package Information (continued)
______________________________________________________________________________________ 19
15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V,
Up to 1Mbps, True RS-232 Transceivers
NOTES
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.
20 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2000 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
相关型号：
MAX3222E-MAX3246E
【15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V, Up to 1Mbps, True RS-232 Transceivers
MAXIM
MAX3222EAP
3.0V to 5.5V, Low-Power, up to 1Mbps, True RS-232 Transceivers Using Four 0.1レF External Capacitors
MAXIM
MAX3222EC/D
【15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V, Up to 1Mbps, True RS-232 Transceivers
MAXIM
MAX3222EC/D+
±15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V, Up to 1Mbps, True RS-232 Transceivers
MAXIM
MAX3222ECAP+
±15kV ESD-Protected, Down to 10nA, 3.0V to 5.5V, Up to 1Mbps, True RS-232 Transceivers
MAXIM
©2020 ICPDF网 联系我们和版权申明