General Description
The MAX3040–MAX3045 is a family of 5V quad RS-
485/RS-422 transmitters designed for digital data trans-
mission over twisted-pair balanced lines. All transmitter
outputs are protected to ±10kV using the Human Body
Model. In addition the MAX3040–MAX3045 withstand
±4kV per IEC 1000-4-4 Electrical Fast Transient/Burst
Stressing. The MAX3040/MAX3043 (250kbps) and the
MAX3041/MAX3044 (2.5Mbps) are slew-rate limited
transmitters that minimize EMI and reduce reflections
caused by improperly terminated cables, thus allowing
error-free transmission.
The MAX3040–MAX3045 feature a hot-swap capability
that eliminates false transitions on the data cable during
power-up or hot insertion. The MAX3042B/MAX3045B
are optimized for data transfer rates up to 20Mbps, the
MAX3041/MAX3044 for data rates up to 2.5Mbps, and
the MAX3040/MAX3043 for data rates up to 250kbps.
The MAX3040–MAX3045 offer optimum performance
when used with the MAX3093E or MAX3095 5V quad
differential line receivers or MAX3094E/MAX3096 3V
quad differential line receivers.
The MAX3040–MAX3045 are ESD-protected pin-compat-
ible, low-power upgrades to the industry-standard
‘SN75174 and ‘DS26LS31C. They are available in space-
saving TSSOP, narrow SO, and wide SO packages.
Applications
Telecommunications Equipment
Industrial Motor Control
Transmitter for ESD-Sensitive Applications
Hand-Held Equipment
Industrial PLCs
Networking
Features
♦ESD Protection: ±10kV—Human Body Model
♦Single +5V Operation
♦Guaranteed Device-to-Device Skew
(MAX3040/MAX3041/MAX3043/MAX3044)
♦Pin-Compatible with ‘SN75174, ‘26LS31C and
LTC487
♦Hot-Swappable for Telecom Applications
♦Up to 20Mbps Data Rate (MAX3042B/MAX3045B)
♦Slew-Rate Limited (Data Rates at 2.5Mbps and
250kbps)
♦2nA Low-Power Shutdown Mode
♦1mA Operating Supply Current
♦±4kV EFT Fast Transient Burst Immunity per IEC
1000-4-4
♦Level 2 Surge Immunity per IEC 1000-4-5,
Unshielded Cable Model
♦Ultra-Small 16-Pin TSSOP, 16-Pin Narrow SO, and
Wide 16-Pin SO
MAX3040–MAX3045
±10kV ESD-Protected, Quad 5V RS-485/RS-422
Transmitters
________________________________________________________________ Maxim Integrated Products 1
Pin Configurations
Selector Guide
Ordering Information
19-2143; Rev 1; 12/01
Ordering Information continued at end of data sheet.
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.
PART
TEMP RANGE
PIN-PACKAGE
DATA
RATE
MAX3040CUE
0°C to +70°C
16 TSSOP
250kbps
MAX3040CSE
0°C to +70°C
16 Narrow SO
250kbps
MAX3040CWE
0°C to +70°C
16 Wide SO
250kbps
MAX3040EUE
-40°C to +85°C
16 TSSOP
250kbps
MAX3040ESE
-40°C to +85°C
16 Narrow SO
250kbps
MAX3040EWE
-40°C to +85°C
16 Wide SO
250kbps
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
T1IN VCC
T4IN
Y4
Z4
EN34
Z3
Y3
T3IN
TOP VIEW
MAX3040
MAX3041
MAX3042B
16 TSSOP/SO
Y1
Z1
Y2
EN12
Z2
T2IN
GND
PART DATA RATE
(bps)
INDUSTRY STANDARD
PINOUT
MAX3040 250k 75174, 34C87, LTC487
MAX3041 2.5M 75174, 34C87, LTC487
MAX3042B 20M 75174, 34C87, LTC487
MAX3043 250k 26LS31
MAX3044 2.5M 26LS31
MAX3045B 20M 26LS31
Pin Configurations continued at end of data sheet.
MAX3040–MAX3045
±10kV ESD-Protected, Quad 5V RS-485/RS-422
Transmitters
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VCC = +5V ±5%, TA= TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA= +25°C.) (Note 1)
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.
All voltages referenced to ground (GND).
Supply Voltage (VCC).............................................................+7V
Control Input Voltage (EN, EN, EN_) .........-0.3V to (VCC + 0.3V)
Driver Input Voltage (T_IN).........................-0.3V to (VCC + 0.3V)
Driver Output Voltage (Y_, Z_)
(Driver Disabled) .............................................-7.5V to +12.5V
Driver Output Voltage (Y_, Z_)
(Driver Enabled) .................................................-7.5V to +10V
Continuous Power Dissipation (TA= +70°C)
16-Pin TSSOP (derate 9.4mW/°C above +70°C) ..........755mW
16-Pin Narrow SO (derate 8.70mW/°C above +70°C) ..696mW
16-Pin Wide SO (derate 9.52mW/°C above +70°C) .....762mW
Operating Temperature Range
MAX304_C_E .......................................................0°C to +70°C
MAX304_E_E ....................................................-40°C to +85°C
Maximum Junction Temperature .....................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
SYMBOL
MIN TYP MAX
UNITS
VCC / 2
±200
±25 ±250
±10
0.002
MAX3040–MAX3045
±10kV ESD-Protected, Quad 5V RS-485/RS-422
Transmitters
_______________________________________________________________________________________ 3
SWITCHING CHARACTERISTICS—MAX3040/MAX3043
(VCC = +5V ±5%, TA= TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA= +25°C.)
SYMBOL
MIN
TYP
MAX
UNITS
250
kbps
0.48
0.75
1.33
0.48
0.75
1.33
t
DSKEW
±350
t
SSKEW
±100
±100
t
ZH(SHDN)
t
ZL(SHDN)
500
500
SWITCHING CHARACTERISTICS—MAX3041/MAX3044
(VCC = +5V ±5%, TA= TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA= +25°C.)
SYMBOL
MIN
TYP
MAX
UNITS
Mbps
150
150
133
133
t
DSKEW
±52
t
SSKEW
±15
±15
400
MAX3040–MAX3045
±10kV ESD-Protected, Quad 5V RS-485/RS-422
Transmitters
4 _______________________________________________________________________________________
Note 1: All currents into the device are positive; all currents out of the device are negative. All voltages are referenced to device
ground unless otherwise noted.
Note 2: ∆VOD and ∆VOC are the changes in VOD and VOC, respectively, when the transmitter input changes state.
Note 3: This input current level is for the hot-swap enable (EN_, EN, EN) inputs and is present until the first transition only. After the
first transition the input reverts to a standard high-impedance CMOS input with input current IIN. For the first 20µs the input
current may be as high as 1mA. During this period the input is disabled.
Note 4: Maximum current level applies to peak current just prior to foldback-current limiting. Minimum current level applies during
current limiting.
SWITCHING CHARACTERISTICS—MAX3041/MAX3044 (continued)
(VCC = +5V ±5%, TA= TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA= +25°C.)
SWITCHING CHARACTERISTICS—MAX3042B/MAX3045B
(VCC = +5V ±5%, TA= TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA= +25°C.)
SYMBOL
MIN
TYP
MAX
UNITS
Mbps
t
DSKEW
t
SSKEW
Figures 2 and 3,
300
t
ZH(SHDN)
300
300
t
ZL(SHDN)
300
400
400
SYMBOL
MIN
TYP
MAX
UNITS
t
ZH(SHDN)
400
400
t
ZL(SHDN)
400
500
500
MAX3040 toc06
OUTPUT LOW VOLTAGE (V)
OUTPUT CURRENT (mA)
54-6 -5 -4 -2 -1 0 1 2-3 3
10
20
30
40
50
60
70
80
0
-7 6
OUTPUT CURRENT vs. TRANSMITTER
OUTPUT HIGH VOLTAGE
0.7
0.8
1.0
0.9
1.1
1.2
02010 30 40 50 60 70
SUPPLY CURRENT vs. TEMPERATURE
MAX3040 toc04
TEMPERATURE (°C)
SUPPLY CURRENT (mA)
VCC = 5.25V
VCC = 5V
VCC = 4.75V
NO LOAD
NO SWITCHING
100 1000
0
10
5
15
20
25
35
30
40
45
0.1 1 10
MAX3040/MAX3043
SUPPLY CURRENT vs. DATA RATE
MAX3040 toc01
DATA RATE (kbps)
SUPPLY CURRENT (mA)
NO LOAD
ALL FOUR TRANSMITTERS
SWITCHING
40
0
0.1 1 10 100 1000 10,000
MAX3041/MAX3044
SUPPLY CURRENT vs. DATA RATE
MAX3040 toc02
DATA RATE (kbps)
SUPPLY CURRENT (mA)
10
5
20
15
35
30
25
NO LOAD
ALL FOUR TRANSMITTERS
SWITCHING
MAX3042B/MAX3045B
SUPPLY CURRENT vs. DATA RATE
DATA RATE (kbps)
0.1 100 1000 10,0001 10 100,000
SUPPLY CURRENT (mA)
60
0
10
20
30
50
40
MAX3040 toc03
NO LOAD
ALL FOUR TRANSMITTERS
SWITCHING
0
20
10
40
30
60
50
70
0426810
OUTPUT CURRENT vs. TRANSMITTER
OUTPUT LOW VOLTAGE
MAX3040 toc06
OUTPUT LOW VOLTAGE (V)
OUTPUT CURRENT (mA)
MAX3040–MAX3045
±10kV ESD-Protected, Quad 5V RS-485/RS-422
Transmitters
_______________________________________________________________________________________ 5
Typical Operating Characteristics
(VCC = +5V, TA = +25°C, unless otherwise noted.)
0
20
10
40
30
60
50
70
021345
OUTPUT CURRENT
vs. DIFFERENTIAL OUTPUT VOLTAGE
MAX3040 toc07
DIFFERENTIAL OUTPUT VOLTAGE (V)
OUTPUT CURRENT (mA)
2.10
2.20
2.15
2.35
2.30
2.25
2.50
2.45
2.40
2.55
0203010 40 50 60 70
TRANSMITTER DIFFERENTIAL OUTPUT
VOLTAGE vs. TEMPERATURE
MAX3040 toc08
TEMPERATURE (°C)
DIFFERENTIAL OUTPUT VOLTAGE (V)
RDIFF = 54Ω
MAX3040–MAX3045
±10kV ESD-Protected, Quad 5V RS-485/RS-422
Transmitters
6 _______________________________________________________________________________________
Pin Description
NAME
MAX3040–MAX3045
±10kV ESD-Protected, Quad 5V RS-485/RS-422
Transmitters
_______________________________________________________________________________________ 7
Detailed Description
The MAX3040–MAX3045 are quad RS-485/RS-422 trans-
mitters. They operate from a single +5V power supply
and are designed to give optimum performance when
used with the MAX3093E/MAX3095 5V quad RS-485/
RS-422 receivers or MAX3094E/MAX3096 3V quad
RS-485/RS-422 receivers. The MAX3040–MAX3045 only
need 1mA of operating supply current and consume 2nA
when they enter a low-power shutdown mode. The
MAX3040–MAX3045 also feature a hot-swap capability
allowing line insertion without erroneous data transfer.
The MAX3042B/MAX3045B are capable of transferring
data up to 20Mbps, the MAX3041/MAX3044 for data
rates up to 2.5Mbps, and the MAX3040/MAX3043 for
data rates up to 250kbps. All transmitter outputs are pro-
tected to ±10kV using the Human Body Model.
±10kV ESD Protection
As with all Maxim devices, ESD-protection structures
are incorporated on all pins to protect against electro-
static discharges (ESD) encountered during handling
and assembly. The MAX3040–MAX3045 transmitter
outputs have extra protection against electrostatic dis-
charges found in normal operation. Maxim’s engineers
have developed state-of-the-art structures to protect
these pins against the application of ±10kV ESD
(Human Body Model), without damage.
ESD Test Conditions
ESD performance depends on a number of conditions.
Contact Maxim for a reliability report that documents
test setup, methodology, and results.
Human Body Model
Figure 6a shows the Human Body Model, and Figure
6b shows the current waveform it generates when dis-
charged into low impedance. This model consists of a
100pF capacitor charged to the ESD voltage of interest,
which is then discharged into the device through a
1.5kΩresistor.
R
R
VOD
VOC
Y
Z
Figure 1. Driver DC Test Circuit
DI
DE
5V
Y
Z
CDIFF
VOD RDIFF
Figure 2. Driver Timing Test Circuit
DI
3V
0
Z
Y
VO
0
-VO
VO
1.5V
tPLH
1/2 VO
10%
tR
90% 90%
tPHL
1.5V
1/2 VO
10%
tF
VDIFF = V (Y) - V (Z)
VDIFF
tSKEW = | tPLH - tPHL |
Figure 3. Driver Propagation Delays
OUTPUT NORMALLY LOW
OUTPUT NORMALLY HIGH
3V
0
Y, Z
VOL
Y, Z
0
1.5V 1.5V
VOL +0.5V
VOH -0.5V
2.5V
2.5V
tZL(SHDN), tZL tLZ
tZH(SHDN), tZH tHZ
DE
Figure 5. Driver Enable and Disable Times
OUTPUT
UNDER TEST
S1
S2
VCC
CL
RL
Figure 4. Driver Enable/Disable Timing Test Load
Machine Model
The Machine Model for ESD testing uses a 200pF stor-
age capacitor and zero-discharge resistance. It mimics
the stress caused by handling during manufacturing
and assembly. Of course, all pins (not just RS-485
inputs) require this protection during manufacturing.
Therefore, the Machine Model is less relevant to the I/O
ports than are the Human Body Model.
±4kV Electrical Fast Transient/Burst Testing
(IEC 1000-4-4)
IEC 1000-4-4 Electrical Fast Transient/Burst (EFT/B) is
an immunity test for the evaluation of electrical and
electronic systems during operating conditions. The
test was adapted for evaluation of integrated circuits
with power applied. Repetitive fast transients with
severe pulsed EMI were applied to signal and control
ports. Over 15,000 distinct discharges per minute are
sent to each interface port of the IC or equipment under
test (EUT) simultaneously with a minimum test duration
time of one minute. This simulates stress due to dis-
placement current from electrical transients on AC
mains, or other telecommunication lines in close prox-
imity. Short rise times and very specific repetition rates
are essential to the validity of the test.
Stress placed on the EUT is severe. In addition to the
controlled individual discharges placed on the EUT,
extraneous noise and ringing on the transmission line
can multiply the number of discharges as well as
increase the magnitude of each discharge. All cabling
was left unterminated to simulate worst-case reflections.
The MAX3040–MAX3045 were setup as specified in
IEC 1000-4-4 and the Typical Operating Circuit of this
data sheet. The amplitude, pulse rise time, pulse dura-
tion, pulse repetition period, burst duration, and burst
period (Figure 8) of the burst generator were all verified
with a digital oscilloscope according to the specifica-
tions in IEC 1000-4-4 sections 6.1.1 and 6.1.2. A simpli-
fied diagram of the EFT/B generator is shown in Figure
7. The burst stresses were applied to Y1–Y4 and Z1–Z4
simultaneously.
IEC 1000-4-4 provides several levels of test severity
(see Table 1). The MAX3040–MAX3045 pass the 4000V
stress, a special category “X” beyond the highest level
for severe (transient) industrial environments for
telecommunication lines.
MAX3040–MAX3045
±10kV ESD-Protected, Quad 5V RS-485/RS-422
Transmitters
8 _______________________________________________________________________________________
CHARGE-CURRENT
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
Cs
100pF
RC
1MΩ
RD
1.5kΩ
HIGH-
VOLTAGE
DC
SOURCE
DEVICE
UNDER
TEST
Figure 6a. Human Body ESD Test Model
IP 100%
90%
36.8%
tRL TIME
tDL
CURRENT WAVEFORM
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
Ir
10%
0
0
AMPERES
Figure 6b. Human Body Model Current Waveform
ON I/O,
SIGNAL, DATA
AND CONTROL
PORTS
EFT
LEVEL
PEAK
VOLTAGE
REPETITION
RATE (kHz)
INDUSTRIAL
ELECTRO-
MAGNETIC
ENVIROMENT
1 250 5 Well protected
2 500 5 Protected
3 1000 5 Typical
4 2000 5 Severe
X 4000 5
MAX3040–MAX3045
Table 1. Test Severity Levels for
Communication Lines
MAX3040–MAX3045
±10kV ESD-Protected, Quad 5V RS-485/RS-422
Transmitters
_______________________________________________________________________________________ 9
IEC 1000-4-4 Burst/Electrical Fast
Transient Test Levels
(For Communication Lines)
The stresses are applied while the MAX3040–MAX3045
are powered up. Test results are reported as:
1) Normal performance within the specification limits.
2) Temporary degradation or loss of function or perfor-
mance which is self-recoverable.
3) Temporary degradation, loss of function or perfor-
mance requiring operator intervention, such as sys-
tem reset.
4) Degradation or loss of function not recoverable due
to damage.
The MAX3040–MAX3045 meets classification 2 listed
above. Additionally, the MAX3040–MAX3045 will not
latchup during the IEC burst stress events.
Hot-Swap Capability
Hot-Swap Inputs
When circuit boards are plugged into a “hot” back-
plane, there can be disturbances to the differential sig-
nal levels that could be detected by receivers
connected to the transmission line. This erroneous data
could cause data errors to an RS-485/RS-422 system.
To avoid this, the MAX3040–MAX3045 have hot-swap
capable inputs.
When a circuit board is plugged into a “hot” backplane
there is an interval during which the processor is going
through its power-up sequence. During this time, the
processor’s output drivers are high impedance and will
be unable to drive the enable inputs of the
MAX3040–MAX3045 (EN, EN, EN_) to defined logic lev-
els. Leakage currents from these high impedance dri-
vers, of as much as 10µA, could cause the enable
inputs of the MAX3040–MAX3045 to drift high or low.
Additionally, parasitic capacitance of the circuit board
could cause capacitive coupling of the enable inputs to
either GND or VCC. These factors could cause the
enable inputs of the MAX3040–MAX3045 to drift to lev-
els that may enable the transmitter outputs (Y_ and Z_).
To avoid this problem, the hot-swap input provides a
method of holding the enable inputs of the
MAX3040–MAX3045 in the disabled state as VCC
ramps up. This hot-swap input is able to overcome the
leakage currents and parasitic capacitances that may
pull the enable inputs to the enabled state.
Hot-Swap Input Circuitry
In the MAX3040–MAX3045 the enable inputs feature
hot-swap capability. At the input there are two NMOS
devices, Q1 and Q2 (Figure 9). When VCC is ramping
up from 0, an internal 10µs timer turns on Q2 and sets
the SR latch, which also turns on Q1. Transistors Q2, a
700µA current sink, and Q1, an 85µA current sink, pull
EN to GND through a 5.6kΩresistor. Q2 is designed to
pull the EN input to the disabled state against an exter-
nal parasitic capacitance of up to 100pF that is trying to
enable the EN input. After 10µs, the timer turns Q2 off
and Q1 remains on, holding the EN input low against
three-state output leakages that might enable EN. Q1
remains on until an external source overcomes the
U = HIGH-VOLTAGE SOURCE
RC = CHARGING RESISTOR
CE = ENERGY STORAGE CAPACITOR
RS = PULSE DURATION SHAPING RESISTOR
RM = IMPEDANCE MATCHING RESISTOR
CD = DC BLOCKING CAPACITOR
SPARK GAP
U
RC
RS
RMCD
CE
50Ω
COAXIAL
OUTPUT
Figure 7. Simplified Circuit Diagram of a Fast Transient/Burst
Generator
REPETITION PERIOD (DEPENDS ON THE TEST VOLTAGE LEVER,
IN CONFORMITY WITH THE VALUES INDICATED IN 6.1.2).
BURST
BURST DURATION
BURST PERIOD 300ms
PULSE
15ms
Figure 8. General Graph of a Fast Transient Burst
MAX3040–MAX3045
required input current. At this time the SR latch resets
and Q1 turns off. When Q1 turns off, EN reverts to a
standard, high-impedance CMOS input. Whenever VCC
drops below 1V, the hot-swap input is reset.
The EN12 and EN34 input structures are identical to the
EN input. For the EN input, there is a complimentary cir-
cuit employing two PMOS devices pulling the EN input
to VCC.
Hot-Swap Line Transient
The circuit of Figure 10 shows a typical offset termina-
tion used to guarantee a greater than 200mV offset
when a line is not driven. The 50pF represents the mini-
mum parasitic capacitance which would exist in a typi-
cal application. In most cases, more capacitance exists
in the system and will reduce the magnitude of the
glitch. During a “hot-swap” event when the driver is
connected to the line and is powered up, the driver
must not cause the differential signal to drop below
200mV. Figures 11 and 12 show the results of the
MAX3040–MAX3045 during power-up for two different
VCC ramp rates (0.1V/µs and 1V/µs). The photos show
the VCC ramp, the single-ended signal on each side of
the 100Ωtermination, the differential signal across the
termination, and shows the hot-swap line transient
stays above the 200mV RS-485 specification.
Operation of Enable Pins
The MAX3040–MAX3045 family has two enable-func-
tional versions:
The MAX3040/MAX3041/MAX3042B have two transmit-
ter enable inputs EN12 and EN34. EN12 controls the
transmitters 1 and 2, and EN34 controls transmitters 3
and 4. EN12 and EN34 are active-high and the part will
enter the low-power shutdown mode when both are
pulled low. The transmitter outputs are high impedance
when disabled (Table 2).
The MAX3043/MAX3044/MAX3045B have two transmit-
ter enable inputs EN and EN, which are active-high and
active-low, respectively. When EN is logic high or EN is
logic low all transmitters are active. When EN is pulled
low and EN is driven high, all transmitters are disabled
and the part enters the low-power shutdown mode. The
transmitter outputs are high impedance when disabled
(Table 3).
Applications Information
Typical Applications
The MAX3040–MAX3045 offer optimum performance
when used with the MAX3093E/MAX3095 5V quad
receivers or MAX3094E/MAX3096 3V quad differential
line receivers. Figure 13 shows a typical RS-485 con-
nection for transmitting and receiving data and Figure
14 shows a typical multi-point connection.
±10kV ESD-Protected, Quad 5V RS-485/RS-422
Transmitters
10 ______________________________________________________________________________________
VCC
TIMER
TIMER
EN
EN
(HOT SWAP)
10µs
85µA
Q1 Q2
5.6kΩ
700µA
Figure 9. Simplified Structure of the Driver Enable Pin (EN)
MAX3040–MAX3045
±10kV ESD-Protected, Quad 5V RS-485/RS-422
Transmitters
______________________________________________________________________________________ 11
VCC
2V/div
Y-Z
(20mV/div)
238mV
Y
200mV/div
Z
200mV/div
Figure 11. Differential Power-Up Glitch (0.1V/µs)
VCC
2V/div
Y-Z
(5mV/div)
238mV
Y
50mV/div
Z
50mV/div
1µs/div
Figure 12. Differential Power-Up Glitch (1V/µs)
TIN
(VCC OR GND)
VCC 5V
1kΩ
1kΩ
0.1kΩ50pF
Y
Z
Figure 10. Differential Power-Up Glitch (Hot Swap)
OUTPUTS
INPUT EN_
Y_ Z_
HH H L
LH L H
X L High-Z High-Z
H = Logic High X = Don’t Care
L = Logic Low High-Z = High Impedance
Table 2. Function Table for MAX3040/
MAX3041/MAX3042B
(Each Pair of Transmitters)
OUTPUTS
INPUT EN EN
YZ
HHX HL
LHX LH
HXL HL
LXL LH
X L H High-Z
High-Z
H = Logic High X = Don’t Care
L = Logic Low High-Z = High Impedance
Table 3. Function Table for MAX3043/
MAX3044/MAX3045B
(All Transmitters)
MAX3040–MAX3045
±10kV ESD-Protected, Quad 5V RS-485/RS-422
Transmitters
12 ______________________________________________________________________________________
Typical Multiple-Point Connection
Figure 14 shows a typical multiple-point connection for
the MAX3040–MAX3045 with the MAX3095. Because of
the high frequencies and the distances involved, high
attention must be paid to transmission-line effects while
using termination resistors. A terminating resistor (RT)
is simply a resistor that should be placed at the
extreme ends of the cable to match the characteristic
impedance of the cable. When the termination resis-
tance is not the same value as the characteristic
impedance of the cable, reflections will occur as the
signal is traveling down the cable. Although some
reflections are inevitable due to the cable and resistor
tolerances, large mismatches can cause significant
reflections resulting in errors in the data. With this in
mind, it is very important to match the terminating resis-
tance and the characteristic impedance as closely as
possible. As a general rule in a multi-drop system, termi-
nation resistors should always be placed at both ends of
the cable.
MAX3095MAX3043–MAX3045
RT
T1IN
T2IN
GND
VCC
R1OUT
R1
D1
EN
EN
G
G
RT R2OUT
R2
D2
T3IN RT R3OUT
R3
D3
T4IN RT R4OUT
R4
D4
GND
VCC
Figure 13. Typical Connection of a Quad Transmitter and a Quad Receiver as a Pair
MAX3040–MAX3045
±10kV ESD-Protected, Quad 5V RS-485/RS-422
Transmitters
______________________________________________________________________________________ 13
Pin Configurations (continued)
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
T1IN VCC
T4IN
Y4
Z4
EN
Z3
Y3
T3IN
TOP VIEW
MAX3043
MAX3044
MAX3045B
16 TSSOP/SO
Y1
Z1
Y2
EN
Z2
T2IN
GND
RT RT
1/4 MAX3040–MAX30451/4 MAX3040–MAX3045
1/4 MAX3040–MAX3045
1/4 MAX3095 1/4 MAX3095
1/4 MAX3095
1/4 MAX3040–MAX3045
1/4 MAX3095
UP TO 32 RS-485
UNIT LOADS
Figure 12. Typical Connection for Multiple-Point RS-485 Bus
Chip Information
TRANSISTOR COUNT: 545
PROCESS: CMOS
PART
TEMP RANGE
PIN-PACKAGE
DATA
RATE
MAX3045BCUE
0°C to +70°C
16 TSSOP
20Mbps
MAX3045BCSE
0°C to +70°C
16 Narrow SO
20Mbps
MAX3045BCWE
0°C to +70°C
16 Wide SO
20Mbps
MAX3045BEUE
-40°C to +85°C
16 TSSOP
20Mbps
MAX3045BESE
-40°C to +85°C
16 Narrow SO
20Mbps
MAX3045BEWE
-40°C to +85°C
16 Wide SO
20Mbps
Ordering Information (continued)
PART
TEMP RANGE
PIN-PACKAGE
DATA
RATE
MAX3041CUE
0°C to +70°C
16 TSSOP
2.5Mbps
MAX3041CSE
0°C to +70°C
16 Narrow SO
2.5Mbps
MAX3041CWE
0°C to +70°C
16 Wide SO
2.5Mbps
MAX3041EUE
-40°C to +85°C
16 TSSOP
2.5Mbps
MAX3041ESE
-40°C to +85°C
16 Narrow SO
2.5Mbps
MAX3041EWE
-40°C to +85°C
16 Wide SO
2.5Mbps
MAX3042BCUE
0°C to +70°C
16 TSSOP
20Mbps
MAX3042BCSE
0°C to +70°C
16 Narrow SO
20Mbps
MAX3042BCWE
0°C to +70°C
16 Wide SO
20Mbps
MAX3042BEUE
-40°C to +85°C
16 TSSOP
20Mbps
MAX3042BESE
-40°C to +85°C
16 Narrow SO
20Mbps
MAX3042BEWE
-40°C to +85°C
16 Wide SO
20Mbps
MAX3043CUE
0°C to +70°C
16 TSSOP
250kbps
MAX3043CSE
0°C to +70°C
16 Narrow SO
250kbps
MAX3043EWE
0°C to +70°C
16 Wide SO
250kbps
MAX3043EUE
-40°C to +85°C
16 TSSOP
250kbps
MAX3043ESE
-40°C to +85°C
16 Narrow SO
250kbps
MAX3043EWE
-40°C to +85°C
16 Wide SO
250kbps
MAX3044CUE
0°C to +70°C
16 TSSOP
2.5Mbps
MAX3044CSE
0°C to +70°C
16 Narrow SO
2.5Mbps
MAX3044CWE
0°C to +70°C
16 Wide SO
2.5Mbps
MAX3044EUE
-40°C to +85°C
16 TSSOP
2.5Mbps
MAX3044ESE
-40°C to +85°C
16 Narrow SO
2.5Mbps
MAX3044EWE
-40°C to +85°C
16 Wide SO
2.5Mbps
MAX3040–MAX3045
±10kV ESD-Protected, Quad 5V RS-485/422
Transmitters
14 ______________________________________________________________________________________
PART TEMP.
RANGE
PIN-PACKAGE
DATA
RATE
MAX3044CUE
0°C to +70°C
16 TSSOP
2.5Mbps
MAX3044CSE
0°C to +70°C
16 Narrow SO
2.5Mbps
MAX3044CWE
0°C to +70°C
16 Wide SO
2.5Mbps
MAX3044EUE
-40°C to +85°C
16 TSSOP
2.5Mbps
MAX3044ESE
-40°C to +85°C
16 Narrow SO
2.5Mbps
MAX3044EWE
-40°C to +85°C
16 Wide SO
2.5Mbps
MAX3045BCUE
0°C to +70°C
16 TSSOP
20Mbps
MAX3045BCSE
0°C to +70°C
16 Narrow SO
20Mbps
MAX3045BCWE
0°C to +70°C
16 Wide SO
20Mbps
MAX3045BEUE
-40°C to +85°C
16 TSSOP
20Mbps
MAX3045BESE
-40°C to +85°C
16 Narrow SO
20Mbps
MAX3045BEWE
-40°C to +85°C
16 Wide SO
20Mbps
Ordering Information (continued)
PART TEMP.
RANGE
PIN-PACKAGE
DATA
RATE
MAX3041CUE
0°C to +70°C
16 TSSOP
2.5Mbps
MAX3041CSE
0°C to +70°C
16 Narrow SO
2.5Mbps
MAX3041CWE
0°C to +70°C
16 Wide SO
2.5Mbps
MAX3041EUE
-40°C to +85°C
16 TSSOP
2.5Mbps
MAX3041ESE
-40°C to +85°C
16 Narrow SO
2.5Mbps
MAX3041EWE
-40°C to +85°C
16 Wide SO
2.5Mbps
MAX3042BCUE
0°C to +70°C
16 TSSOP
20Mbps
MAX3042BCSE
0°C to +70°C
16 Narrow SO
20Mbps
MAX3042BCWE
0°C to +70°C
16 Wide SO
20Mbps
MAX3042BEUE
-40°C to +85°C
16 TSSOP
20Mbps
MAX3042BESE
-40°C to +85°C
16 Narrow SO
20Mbps
MAX3042BEWE
-40°C to +85°C
16 Wide SO
20Mbps
MAX3043CUE
0°C to +70°C
16 TSSOP
250kbps
MAX3043CSE
0°C to +70°C
16 Narrow SO
250kbps
MAX3043EWE
0°C to +70°C
16 Wide SO
250kbps
MAX3043EUE
-40°C to +85°C
16 TSSOP
250kbps
MAX3043ESE
-40°C to +85°C
16 Narrow SO
250kbps
MAX3043EWE
-40°C to +85°C
16 Wide SO
250kbps
Pin Configurations (continued)
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
T1IN VCC
T4IN
Y4
Z4
EN
Z3
Y3
T3IN
TOP VIEW
MAX3043
MAX3044
MAX3045B
16 TSSOP/SO
Y1
Z1
Y2
EN
Z2
T2IN
GND
MAX3040–MAX3045
±10kV ESD-Protected, Quad 5V RS-485/RS-422
Transmitters
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.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 15
© 2001 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
Package Information (continued)
SOICW.EPS