General Description
The MAX3188E/MAX3189E single RS-232 transmitters
in a SOT23-6 package are for space- and cost-con-
strained applications requiring minimal RS-232 commu-
nications. These devices consume only 150A of
supply current from 4.5V to 6V supplies. They fea-
ture a shutdown input that reduces current consump-
tion to only 1A and forces the transmitter output into a
high-impedance state. RS-232 data transmission is guar-
anteed up to 250kbps with the MAX3188E and up to
1Mbps with the MAX3189E.
The MAX3188E/MAX3189E are EIA/TIA-232 transmitters
that convert CMOS/TTL logic levels to RS-232-compliant
signals. The transmitter output is protected to 15kV
using the IEC 1000-4-2 Air-Gap Discharge method, to
8kV using the IEC 1000-4-2 Contact Discharge
method, and to 15kV per the Human Body Model,
ensuring strict compliance with international standards.
The MAX3188E/MAX3189E transmitters have a standard
inverting output.
Applications
Diagnostic Ports
Telecommunications
Networking Equipment
Set-Top Boxes
Digital Cameras
Hand-Held Equipment
Features
o Small 6-Pin SOT23 Package
o ESD-Protected RS-232 Output
15kV per Human Body Model
8kV per IEC 1000-4-2, Contact Discharge
15kV per IEC 1000-4-2, Air-Gap Discharge
o 150A Operating Supply Current
o Shutdown Reduces Supply Current to 1A
o Guaranteed Data Rate
1Mbps (MAX3189E)
250kbps (MAX3188E)
o Three-State RS-232 Transmitter Output
o No External Components
MAX3188E/MAX3189E
15kV ESD-Protected, 1Mbps, 1A
RS-232 Transmitters in SOT23-6
________________________________________________________________ Maxim Integrated Products
1
GND
TOUT
TIN
1
6
V
CC
5
VEE
SHDN
MAX3188E
MAX3189E
SOT23-6
TOP VIEW
2
3
4
SHDN
V
CC
V
EE
TIN
GND
TOUT
MAX3188E
MAX3189E
1
6
3
2
4
5
C
BYPASS1
0.1
F
C
BYPASS2
0.1
F
-5.4V
+5.4V
CAPACITORS MAY BE
POLARIZED OR UNPOLARIZED.
Typical Operating Circuit
19-1604; Rev 0; 1/00
Pin Configuration
Ordering Information
AAHE
AAHD
TOP
MARK
6 SOT23-6
6 SOT23-6
PIN-
PACKAGE
TEMP. RANGE
-40C to +85C
-40C to +85C
MAX3189EEUT-T
MAX3188EEUT-T
PART
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.
MAX3188E/MAX3189E
15kV ESD-Protected, 1Mbps, 1A
RS-232 Transmitters in SOT23-6
2
_______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(V
CC
= +4.5V to +6V, V
EE
= -4.5V to -6V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V
CC
= +5.4V, V
EE
= -5.4V,
and T
A
= +25C.) (Note 2)
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.
Note 1: V
CC
and V
EE
can have maximum magnitudes of 7V, but their absolute difference cannot exceed 13V.
V
CC
to GND (Note 1) ................................................-0.3V to +7V
V
EE
to GND (Note 1).................................................+0.3V to -7V
V
CC
to V
EE
(Note 1) .............................................................+13V
TIN, SHDN to GND ...................................................-0.3V to +7V
TOUT to GND (SHDN = GND)..........................................13.2V
TOUT to GND (SHDN = V
CC
) ................................................7V
Output Short-Circuit Duration.....................................Continuous
Continuous Power Dissipation (T
A
= +70C)
6-Pin SOT23 (derate 8.7mW/C above +70C)..........691mW
Operating Temperature Range ...........................-40C to +85C
Junction Temperature ......................................................+150C
Storage Temperature Range .............................-65C to +150C
Lead Temperature (soldering, 10s) .................................+300C
MAX3188E
MAX3189E
MAX3188E
MAX3189E
MAX3188E
R
L
= 3k
to 7k,
C
L
= 150pF to 1000pF,
measured from -3V
to +3V or +3V to -3V,
V
CC
= 5.4V, V
EE
=
-5.4V, T
A
= +25C
|t
PHL
- t
PLH
|, Figure 1
R
L
= 3k
,
C
L
= 1000pF
V
CC
= V
EE
= 0, V
TOUT
= 2V
V
CC
= 5.4V, V
EE
= -5.4V, R
L
= 3k
V
SHDN
= 5V
V
SHDN
= 5V
V
SHDN
= 0
V
CC
= 4.5V, V
EE
= -4.5V, R
L
= 3k
CONDITIONS
24
150
V/s
6
30
Transition-Region Slew Rate
25
MAX3189E
ns
100
t
TS
Transmitter Skew
1
Mbps
0.25
Maximum Data Rate
A
25
I
TOUT
Output Leakage Current
mA
35
60
Output Short-Circuit Current
300
R
TOUT
Output Resistance
5
V
3.7
V
TOUT
Output Voltage Swing
V
-6
-4.5
V
EE
Negative Supply Voltage
V
4.5
6
V
CC
Positive Supply Voltage
mV
100
TIN Input Hysteresis
A
0.01
1
Input Leakage
V
2.0
V
IH
Input Logic Threshold High
V
0.8
V
IL
Input Logic Threshold Low
A
170
I
CC
Positive Supply Current
A
45
I
EE
Negative Supply Current
A
0.2
1
Shutdown Supply Current
UNITS
MIN
TYP
MAX
SYMBOL
PARAMETER
s
2
t
EN
Transmitter Enable Time
V
OUT
= 12V; V
CC
= V
EE
= 0 or V
CC
= 5.4V,
V
EE
= -5.4V; SHDN = 0
DC CHARACTERISTICS
INPUT LOGIC (TIN, SHDN)
TRANSMITTER OUTPUTS
TIMING CHARACTERISTICS
MAX3188E/MAX3189E
15kV ESD-Protected, 1Mbps, 1A
RS-232 Transmitters in SOT23-6
_______________________________________________________________________________________
3
0
1.5
1.0
0.5
2.0
2.5
3.0
0
400
300
100 200
500 600 700 800 900 1000
SUPPLY CURRENT vs. TRANSMITTER
FREQUENCY (C
L
= 150pF)
MAX3188E/9E toc01
TRANSMITTER FREQUENCY (kHz)
SUPPLY CURRENT (mA)
I
CC
(MAX3189E)
I
EE
(MAX3189E)
I
EE
(MAX3188E)
I
CC
(MAX3188E)
0
6
4
2
8
10
12
0
400
300
100 200
500 600 700 800 900 1000
SUPPLY CURRENT vs. TRANSMITTER
FREQUENCY (C
L
= 1000pF)
MAX3188E/9E toc02
TRANSMITTER FREQUENCY (kHz)
SUPPLY CURRENT (mA)
I
CC
= I
EE
MAX3189E
MAX3188E
0
1
2
3
4
5
6
7
8
0
500
1000
1500
2000
2500
MAX3188E
SUPPLY CURRENT vs.
OUTPUT CAPACITANCE
MAX3188E/9E toc03
OUTPUT CAPACITANCE (pF)
SUPPLY CURRENT (mA)
250kbps
120kbps
20kbps
0
4
2
8
6
12
10
14
0
1000
500
1500
2000
2500
MAX3189E
SUPPLY CURRENT vs.
OUTPUT CAPACITANCE
MAX3188E/9E toc04
OUTPUT CAPACITANCE (pF)
SUPPLY CURRENT (mA)
250kbps
120kbps
20kbps
1Mbps
0
4
2
8
6
12
10
14
0
1000
500
1500
2000
2500
MAX3188E
SLEW RATE vs. OUTPUT CAPACITANCE
MAX3188E/9E toc05
OUTPUT CAPACITANCE (pF)
SLEW RATE (V/
s)
-SLEW
+SLEW
0
20
10
50
40
30
80
70
60
90
0
1000
500
1500
2000
2500
MAX3189E
SLEW RATE vs. OUTPUT CAPACITANCE
MAX3188E/9E toc06
OUTPUT CAPACITANCE (pF)
SLEW RATE (V/
s)
-SLEW
+SLEW
Typical Operating Characteristics
(V
CC
= +5.4V, V
EE
= -5.4V, R
L
= 3k
, T
A
= +25C, unless otherwise noted.)
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +4.5V to +6V, V
EE
= -4.5V to -6V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V
CC
= +5.4V, V
EE
= -5.4V,
and T
A
= +25C.) (Note 2)
Note 2: All devices are 100% tested at T
A
= +25C. All limits over temperature are guaranteed by design.
PARAMETER
SYMBOL
MIN
TYP
MAX
UNITS
15
8
TOUT
15
kV
CONDITIONS
Human Body Model
IEC 1000-4-2 Contact Discharge
IEC 1000-4-2 Air-Gap Discharge
ESD PROTECTION
Detailed Description
The MAX3188E/MAX3189E are EIA/TIA-232 transmitters
that convert CMOS/TTL logic levels to RS-232 signals.
They operate on 4.5V to 6V supplies and feature
enhanced electrostatic discharge protection (see ESD
Protection). The MAX3188E guarantees a 250kbps data
rate, and the MAX3189E guarantees a 1Mbps data rate
with worst-case loads of 3k
in parallel with 1000pF.
The MAX3188E/MAX3189E invert the TOUT signal relative
to TIN (standard RS-232). The transmitter input does
not have a pull-up resistor and should be connected to
GND if unused.
Shutdown
The MAX3188E/MAX3189E feature a shutdown input.
Drive SHDN low to reduce the supply current to 1A
(max). Shutdown also forces TOUT into a high-imped-
ance state, allowing the signal line to be safely con-
trolled by other transmitters. Drive SHDN high for
normal operation.
ESD Protection
As with all Maxim devices, ESD protection structures are
incorporated on all pins to protect against ESD encoun-
tered during handling and assembly. The MAX3188E/
MAX3189Es' transmitter output has extra protection
against static electricity. Maxim has developed state-of-
the-art structures enabling this pin to withstand ESD up
MAX3188E/MAX3189E
15kV ESD-Protected, 1Mbps, 1A
RS-232 Transmitters in SOT23-6
4
_______________________________________________________________________________________
Pin Description
50%
50%
50%
50%
t
PLH
t
PHL
+5V
-5V
TOUT
TIN
V
IH
V
IL
Figure 1. Transmitter Propagation-Delay Timing
SHDN
TOUT
0
-5V
+5V
0
+2V
1
s/div
MAX3188E
TRANSMITTER OUTPUT
SHUTDOWN WAVEFORM
MAX3188E/9E toc07
C
L
= 150pF
SHDN
TOUT
0
-5V
+5V
0
+2V
1
s/div
MAX3189E
TRANSMITTER OUTPUT
SHUTDOWN WAVEFORM
MAX3188E/9E toc08
C
L
= 150pF
Typical Operating Characteristics (continued)
(V
CC
= +5.4V, V
EE
= -5.4V, R
L
= 3k
, T
A
= +25C, unless otherwise noted.)
NAME
FUNCTION
1
SHDN
Active-Low Shutdown. Pull low to
reduce the supply current and to force
TOUT into a high-impedance state.
2
GND
Ground
PIN
3
TIN
TTL/CMOS Transmitter Input
4
TOUT
RS-232 Transmitter Output
6
V
CC
Positive Supply Voltage
5
V
EE
Negative Supply Voltage
to 15kV without damage or latch-up. The MAX3188E/
MAX3189E's transmitter output is characterized for pro-
tection to the following limits:
15kV using the Human Body Model
8kV using the Contact Discharge method specified
in IEC 1000-4-2
15kV using the Air-Gap Discharge method specified
in IEC 1000-4-2
Human Body Model
Figure 2 shows the Human Body Model, and Figure 3
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 interest,
and then discharged into the test device through a
1.5k
resistor.
IEC 1000-4-2
The IEC 1000-4-2 standard covers ESD testing and
performance of finished equipment; it does not specifi-
cally refer to ICs. The MAX3188E/MAX3189E enable
the design of equipment that meets the highest level
(Level 4) 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, the ESD withstand voltage measured to this
standard is generally lower than that measured using
the Human Body. Figure 4 shows the IEC 1000-4-2
model, and Figure 5 shows the current waveform for
the 8kV IEC 1000-4-2 Level 4 ESD Contact Discharge
test. The Air-Gap test involves approaching the device
with a charged probe. The Contact Discharge method
connects the probe to the device before the probe is
energized.
Power-Supply Decoupling
In most circumstances, 0.1F bypass capacitors are
adequate for power-supply decoupling. Connect the
bypass capacitors as close to the IC as possible.
MAX3188E/MAX3189E
15kV ESD-Protected, 1Mbps, 1A
RS-232 Transmitters in SOT23-6
_______________________________________________________________________________________
5
CHARGE-CURRENT
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
Cs
100pF
R
C
1M
R
D
1500
HIGH-
VOLTAGE
DC
SOURCE
DEVICE
UNDER
TEST
Figure 2. Human Body ESD Test Model
I
P
100%
90%
36.8%
t
RI
TIME
t
DL
CURRENT WAVEFORM
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
Ir
10%
0
0
AMPERES
Figure 3. Human Body Model Current Waveform
CHARGE-CURRENT
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
Cs
150pF
R
C
50M
TO 100M
R
D
330
HIGH-
VOLTAGE
DC
SOURCE
DEVICE
UNDER
TEST
Figure 4. IEC 1000-4-2 ESD Test Model
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