19-0426; Rev 1; 2/03
±15kV ESD-Protected, Quad,
Low-Power RS-232 Line Receiver
_______________General Description
The MAX1489E quad, low-power line receiver is
designed for EIA/TIA-232, EIA/TIA-562, and CCITT V.28
communications in harsh environments. Each receiver
input is protected against ±15kV electrostatic dis-
charge (ESD) shocks. These inputs have a ±25V range
and feature hysteresis and time-domain filtering. The
outputs are TTL and CMOS compatible. The MAX1489E
has a 120kbps guaranteed data rate. Supply current is
typically 350µA.
The MAX1489E is pin compatible with the MC1489,
MC14C89, SN75189, SN75C189, DS1489, and
DS14C89. It is available in 14-pin plastic DIP and SO
packages.
____________________________Features
o
Enhanced ESD Protection:
±15kV—Human Body Model
±8kV—IEC1000-4-2, Contact Discharge
±15kV—IEC1000-4-2, Air-Gap Discharge
o
Latchup Free During an ESD Event
o
Low 350µA Supply Current
o
Input Hysteresis and Time-Domain Filtering
Eliminate the Need for External Filtering
o
Stable Input Thresholds
o
Pin Compatible with MC1489, MC14C89, SN75189,
SN75C189, DS1489, and DS14C89
MAX1489E
________________________Applications
PC Motherboards
Modems
Interfacing Data Terminal Equipment (DTE) with
Data Circuit-Terminating Equipment (DCE)
Equipment Meeting IEC1000-4-2 (formerly
IEC801-2) or ±15kV ESD Protection
______________Ordering Information
PART
MAX1489ECPD
MAX1489ECSD
MAX1489EC/D
MAX1489EEPD
MAX1489EESD
TEMP RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
14 Plastic DIP
14 SO
Dice*
14 Plastic DIP
14 SO
* Dice are specified at T
A
= +25°C.
__________Typical Operating Circuit
__________________Pin Configuration
1
⁄
4
MAX1488E
1
⁄
4
MAX1489E
TOP VIEW
INPUT A 1
TTL/CMOS
LOGIC
INTERCONNECTING
CABLE
TTL/CMOS
LOGIC
N.C. 2
OUTPUT A 3
INPUT B 4
N.C. 5
1
⁄
4
MAX1489E
SIGNAL GROUND
PC
MOTHERBOARD
(DTE)
MODEM
(DCE)
1
⁄
4
MAX1488E
OUTPUT B 6
GND 7
MAX1489E
14 V
CC
13 INPUT D
12 N.C.
11 OUTPUT D
10 INPUT C
9
8
N.C.
OUTPUT C
DIP/SO
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
±15kV ESD-Protected, Quad,
Low-Power RS-232 Line Receiver
MAX1489E
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (V
CC
).............................................................+7V
Input Voltage (V
IN
) ...............................................................±30V
Output Short-Circuit Current
(Shorted to GND or V
CC
) (Note 1) ............................Self Limiting
Continuous Power Dissipation (T
A
= +70°C)
Plastic DIP (derate 10.00mW/°C above +70°C) ..........800mW
SO (derate 8.7mW/°C above +70°C) ...........................695mW
Operating Temperature Ranges
MAX1489EC_D ...................................................0°C to +70°C
MAX1489EE_D ................................................-40°C to +85°C
Storage Temperature Range .............................-65°C to +160°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V
CC
= 5V ±10%, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V
CC
= 5V, T
A
= +25°C.)
PARAMETER
DC CHARACTERISTICS
Output Voltage High
Output Voltage Low
Output Short-Circuit Current
(Note 1)
Supply Current
Input Voltage Range
Input Voltage High
Input Voltage Low
Input Hysteresis
Input Resistance
TIMING CHARACTERISTICS
Output Propagation Delay,
Low to High
Output Propagation Delay,
High to Low
Output Propagation Delay Skew,
I
t
PLH
- t
PHL
I
Output Transition Time
Input Noise Rejection
Guaranteed Data Rate
ESD CHARACTERISTICS
Human Body Model
ESD Protection
IEC1000-4-2 (Contact Discharge)
IEC1000-4-2 (Air-Gap Discharge)
Note 1:
Only one output may be shorted at a time.
Note 2:
See Noise Pulse Rejection graph in
Typical Operating Characteristics
section.
±15
±8
±15
kV
t
PLH
t
PHL
t
SKEW
t
TR
t
N
DR
Figure 1
Figure 1
Figure 1
V
OUT
= 10% to 90%
Pulse amplitude = 5V (Note 2)
120
1.38
1.45
70
35
1.0
240
120
4.0
4.0
µs
µs
ns
ns
µs
kbps
V
OH
V
OL
I
OS
I
CC
V
IN
V
IH
V
IL
V
HYST
R
IN
3.0
-25
1.60
0.75
2.17
1.06
1.11
5.0
7.0
V
IN
≤
0.4V
I
OUT
= -20µA
I
OUT
= -3.2mA
3.5
2.5
-35
60
260
600
25
2.60
1.30
4.99
4.41
0.17
0.4
V
V
mA
µA
V
V
V
V
kΩ
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
V
IN
≥
2.4V, I
OUT
= 3.2mA
Shorted to GND
Shorted to V
CC
2
_______________________________________________________________________________________
±15kV ESD-Protected, Quad,
Low-Power RS-232 Line Receiver
__________________________________________Typical Operating Characteristics
(V
CC
= 5V, T
A
= +25°C, unless otherwise noted.)
MAX1489E
PROPAGATION DELAY vs. TEMPERATURE
MAX1489E-01
PROPAGATION DELAY SKEW
vs. TEMPERATURE
MAX1489E-02
NOISE PULSE REJECTION
V
IN
= (V
IL
+ V
IH
) ± PULSE AMP,
2
2
f = 300kHz
MAX1489E-03
2.2
800
PROPAGATION DELAY SKEW (ns)
8
INPUT PULSE AMPLITUDE (Vp-p)
PROPAGATION DELAY (µs)
1.8
600
6
1.4
t
PHL
t
PLH
400
V
CC
= 5.25V
200
V
CC
= 5V
V
CC
= 4.75V
4
1.0
2
0.6
-40
-15
10
35
60
85
TEMPERATURE (°C)
0
-40
-15
10
35
60
85
TEMPERATURE (°C)
0
0.7
1.1
1.5
1.9
2.3
2.7
INPUT PULSE WIDTH (µs)
_____________________Pin Description
3.0V
PIN
1, 4, 10,
13
2, 5, 9,
12
3, 6, 8,
11
7
14
NAME
INPUT_
N.C.
OUTPUT_
GND
V
CC
FUNCTION
Receiver Inputs
No Connect—not internally
connected
Receiver Outputs
Ground
S.G.
0V
1.5V
t
PHL
90%
t
PLH
V
OH
V
OUT
50%
50%
10%
Supply Voltage
V
OL
t
TR
V
CC
t
TR
SIGNAL
GENERATOR
(S.G.)
50pF
V
OUT
NOTE: S.G. SET TO f = 20kHz;
DUTY CYCLE = 50%;
t
R
, t
F
< 5.0ns
Figure 1. Timing Diagram
_______________________________________________________________________________________
3
±15kV ESD-Protected, Quad,
Low-Power RS-232 Line Receiver
MAX1489E
R
C
1MΩ
CHARGE-CURRENT
LIMIT RESISTOR
HIGH-
VOLTAGE
DC
SOURCE
R
D
1500Ω
DISCHARGE
RESISTANCE
DEVICE
UNDER
TEST
I
P
100%
90%
AMPERES
Cs
100pF
STORAGE
CAPACITOR
36.8%
10%
0
0
t
RL
TIME
t
DL
CURRENT WAVEFORM
Ir
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
Figure 2a. Human Body ESD Test Model
Figure 2b. Human Body Model Current Waveform
_______________Detailed Description
±15kV ESD Protection
As with all Maxim devices, ESD protection structures
are incorporated on all pins to protect against electro-
static discharges encountered during handling and
assembly. The MAX1489E receiver inputs have extra
protection against static electricity found in normal
operation. Maxim’s engineers developed state-of-the-
art structures to protect these pins against ESD of
±15kV without damage. After an ESD event, the
MAX1489E keeps working without latchup.
ESD protection can be tested in various ways; the
receiver inputs are characterized for protection to the
following:
1) ±15kV using the Human Body Model
2) ±8kV using the Contact Discharge method speci-
fied in IEC1000-4-2 (formerly IEC801-2)
3) ±15kV using the Air-Gap Discharge method speci-
fied in IEC1000-4-2 (formerly IEC801-2).
ESD Test Conditions
Contact Maxim for a reliability report that documents
test setup, methodology, and results.
Human Body Model
Figure 2a shows the Human Body Model, and Figure
2b shows the current waveform it generates when dis-
charged into a low impedance. This model consists of
a 100pF capacitor charged to the ESD voltage of inter-
est, which is then discharged into the test device
through a 1.5kΩ resistor.
IEC1000-4-2
The IEC100-4-2 standard covers ESD testing and per-
formance of finished equipment; it does not specifically
refer to integrated circuits. The MAX1489E helps you
design equipment that meets Level 4 (the highest level)
of IEC1000-4-2, without additional ESD protection com-
ponents.
The major difference between tests done using the
Human Body Model and IEC1000-4-2 is higher peak cur-
rent in IEC1000-4-2. Because series resistance is lower
in the IEC1000-4-2 ESD test model (Figure 3a), the ESD
withstand voltage measured to this standard is generally
lower than that measured using the Human Body Model.
Figure 3b shows the current waveform for the ±8kV
IEC1000-4-2 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.
4
_______________________________________________________________________________________
±15kV ESD-Protected, Quad,
Low-Power RS-232 Line Receiver
MAX1489E
R
C
50MΩ to 100MΩ R
D
330Ω
CHARGE-CURRENT
LIMIT RESISTOR
HIGH-
VOLTAGE
DC
SOURCE
DISCHARGE
RESISTANCE
DEVICE
UNDER
TEST
10%
t
r
= 0.7ns to 1ns
30ns
60ns
t
I
100%
90%
I
PEAK
Cs
150pF
STORAGE
CAPACITOR
Figure 3a. IEC1000-4-2 ESD Test Model
Figure 3b. IEC1000-4-2 ESD Generator Current Waveform
Machine Model
The Machine Model for ESD testing uses a 200pF stor-
age capacitor and zero-discharge resistance. Its objec-
tive is to mimic the stress caused by contact that
occurs with handling and assembly during manufactur-
ing. Of course, all pins (not just RS-232 inputs and out-
puts) require this protection during manufacturing.
Therefore, the Machine Model is less relevant to the I/O
ports than the Human Body Model and IEC1000-4-2.
__________ Applications Information
Use proper layout to ensure other devices on your
board are not damaged in an ESD strike. Currents as
high as 60A can instantaneously pass through the
ground pin, so it is important to minimize the ground-
lead return path to the power supply. A separate return
path to the power supply is recommended. Trace
widths should be greater than 40 mils. V
CC
must be
bypassed with 0.1µF capacitors as close to the part as
possible to ensure maximum ESD protection.
_______________________________________________________________________________________
5
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