Maxim MAX3033EEUE ±15kv esd-protected, 3.3v quad rs-422 transmitter Datasheet

19-2671; Rev 0; 10/02
±15kV ESD-Protected, 3.3V Quad
RS-422 Transmitters
Features
♦ Meet TIA/EIA-422-B (RS-422) and ITU-T V.11
Recommendation
♦ ±15kV ESD Protection on Tx Outputs
♦ Hot-Swap Functionality
♦ Guaranteed 20Mbps Data Rate (MAX3030E,
MAX3032E)
♦ Slew-Rate-Controlled 2Mbps Data Rate
(MAX3031E, MAX3033E)
♦ Available in 16-Pin TSSOP and Narrow SO
Packages
♦ Low-Power Design (<330µW, VCC = 3.3V Static)
♦ +3.3V Operation
♦ Industry-Standard Pinout
♦ Thermal Shutdown
Applications
Ordering Information
Telecom Backplanes
PART
TEMP RANGE
PIN-PACKAGE
0°C to +70°C
16 SO (Narrow)
MAX3030ECUE
0°C to +70°C
16 TSSOP
MAX3030EESE
-40°C to +85°C
16 SO (Narrow)
MAX3030EEUE
-40°C to +85°C
16 TSSOP
MAX3031ECSE
0°C to +70°C
16 SO (Narrow)
MAX3031ECUE
0°C to +70°C
16 TSSOP
MAX3031EESE
-40°C to +85°C
MAX3031EEUE
-40°C to +85°C
MAX3032ECSE
0°C to +70°C
16 SO (Narrow)
MAX3032ECUE
0°C to +70°C
16 TSSOP
14 DO4+
MAX3032EESE
-40°C to +85°C
13 DO4-
MAX3032EEUE
-40°C to +85°C
12 EN3&4
MAX3033ECSE
0°C to +70°C
16 SO (Narrow)
16 TSSOP
V.11/X.21 Interface
MAX3030ECSE
Industrial PLCs
Motor Control
Pin Configurations
TOP VIEW
DI1 1
16 VCC
DI1 1
16 VCC
DO1+ 2
15 DI4
DO1+ 2
15 DI4
DO1- 3
EN 4
DO2- 5
MAX3030E/
MAX3031E
14 DO4+
DO1- 3
13 DO4-
EN1&2 4
MAX3032E/
MAX3033E
16 SO (Narrow)
16 TSSOP
16 SO (Narrow)
16 TSSOP
12 EN
DO2- 5
DO2+ 6
11 DO3-
DO2+ 6
11 DO3-
MAX3033ECUE
0°C to +70°C
DI2 7
10 DO3+
DI2 7
10 DO3+
MAX3033EESE
-40°C to +85°C
16 SO (Narrow)
MAX3033EEUE
-40°C to +85°C
16 TSSOP
GND 8
9
TSSOP/SO
DI3
GND 8
9
DI3
TSSOP/SO
________________________________________________________________ Maxim Integrated Products
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.
1
MAX3030E–MAX3033E
General Description
The MAX3030E–MAX3033E family of quad RS-422
transmitters send digital data transmission signals over
twisted-pair balanced lines in accordance with TIA/EIA422-B and ITU-T V.11 standards. All transmitter outputs
are protected to ±15kV using the Human Body Model.
The MAX3030E–MAX3033E are available with either a
2Mbps or 20Mbps guaranteed baud rate. The 2Mbps
baud rate transmitters feature slew-rate-limiting to minimize EMI and reduce reflections caused by improperly
terminated cables.
The 20Mbps baud rate transmitters feature low-static
current consumption (ICC < 100µA), making them ideal
for battery-powered and power-conscious applications.
They have a maximum propagation delay of 16ns and a
part-to-part skew less than 5ns, making these devices
ideal for driving parallel data. The MAX3030E–
MAX3033E feature hot-swap capability that eliminates
false transitions on the data cable during power-up or
hot insertion.
The MAX3030E–MAX3033E are low-power, ESD-protected, pin-compatible upgrades to the industry-standard 26LS31 and SN75174. They are available in
space-saving 16-pin TSSOP and SO packages.
MAX3030E–MAX3033E
±15kV ESD-Protected, 3.3V Quad
RS-422 Transmitters
ABSOLUTE MAXIMUM RATINGS
(All Voltages Are Referenced to Device Ground, Unless
Otherwise Noted)
VCC ........................................................................................+6V
EN1&2, EN3&4, EN, EN............................................-0.3V to +6V
DI_ ............................................................................-0.3V to +6V
DO_+, DO_- (normal condition) .................-0.3V to (VCC + 0.3V)
DO_+, DO_- (power-off or three-state condition).....-0.3V to +6V
Driver Output Current per Pin.........................................±150mA
Continuous Power Dissipation (TA = +70°C)
16-Pin SO (derate 8.70mW/°C above +70°C)..............696mW
16-Pin TSSOP (derate 9.40mW/°C above +70°C) .......755mW
Operating Temperature Ranges
MAX303_EC_ ......................................................0°C to +70°C
MAX303_EE_ ...................................................-40°C to +85°C
Junction Temperature ......................................................+150°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.
DC ELECTRICAL CHARACTERISTICS
(3V ≤ VCC ≤ 3.6V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +3.3V and TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DRIVER OUTPUT: DO_+, DO_VOD1
RL = 100Ω, Figure 1
VOD2
RL = ∞, Figure 1
3.6
VOD3
RL = 3.9kΩ (for compliance with V.11),
Figure 1
3.6
Change in Differential Output
Voltage
∆VOD
RL = 100Ω (Note 2)
Driver Common-Mode Output
Voltage
VOC
RL = 100Ω, Figure 1
Change in Common-Mode
Voltage
∆VOC
RL = 100Ω (Note 2)
Differential Driver Output
Three-State Leakage Current
IOZ
VOUT = VCC or GND, driver disabled
Output Leakage Current
IOFF
VCC = 0V, VOUT = 3V or 6V
Driver Output Short-Circuit
Current
ISC
VOUT = 0V, VIN = VCC or GND
(Note 3)
2.0
-0.4
-0.4
V
+0.4
V
3
V
+0.4
V
±10
µA
20
µA
-150
mA
INPUTS: EN, EN, EN1&2, EN3&4
Input High Voltage
VIH
Input Low Voltage
VIL
Input Current
Hot-Swap Driver Input Current
2.0
V
ILEAK
IHOTSWAP
EN, EN, EN1&2, EN3&4 (Note 4)
0.4
V
±2
µA
±200
µA
100
µA
SUPPLY CURRENT
Supply Current
ICC
No load
THERMAL PROTECTION
Thermal-Shutdown Threshold
TSH
Thermal-Shutdown Hysteresis
ESD Protection DO_
2
Human Body Model
160
°C
10
°C
±15
kV
_______________________________________________________________________________________
±15kV ESD-Protected, 3.3V Quad
RS-422 Transmitters
(3V ≤ VCC ≤ 3.6V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +3.3V and TA = +25°C.)
PARAMETER
SYMBOL
Driver Propagation Delay
Low to High
tDPLH
Driver Propagation Delay
High to Low
tDPHL
CONDITIONS
MIN
TYP
MAX
UNITS
8
16
ns
RL = 100Ω, CL = 50pF (10% to 90%),
Figures 2, 3
10
ns
RL = 100Ω, CL = 50pF, VCC = 3.3V
±2
ns
RL = 100Ω, CL = 50pF, VCC = 3.3V,
∆TMAX = +5°C
5
ns
RL = 100Ω, CL = 50pF, Figures 2, 3
Differential Transition Time, Low
to High
tR
Differential Transition Time, High
to Low
tF
Differential Skew (Same Channel)
|tDPLH - tDPHL|
tSK1
Skew Driver to Driver
(Same Device)
tSK2
Skew Part to Part
tSK3
Maximum Data Rate
20
Mbps
Driver Enable to Output High
tDZH
S2 closed, RL = 500Ω, CL = 50pF,
Figures 4, 5
50
ns
Driver Enable to Output Low
tDZL
S1 closed, RL = 500Ω, CL = 50pF,
Figures 4, 5
50
ns
Driver Disable Time from Low
tDLZ
S1 closed, RL = 500Ω, CL = 50pF,
Figures 4, 5
50
ns
Driver Disable Time from High
tDHZ
S2 closed, RL = 500Ω, CL = 50pF,
Figures 4, 5
50
ns
TYP
MAX
UNITS
40
70
ns
50
ns
±10
ns
SWITCHING CHARACTERISTICS—MAX3031E, MAX3033E
(3V ≤ VCC ≤ 3.6V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +3.3V and TA = +25°C.)
PARAMETER
SYMBOL
Driver Propagation Delay
Low to High
tDPLH
Driver Propagation Delay
High to Low
tDPHL
Differential Transition Time,
Low to High
Differential Transition Time,
High to Low
CONDITIONS
MIN
RL = 100Ω, CL = 50pF, Figures 2, 3
tR
RL = 100Ω, CL = 50pF (10% to 90%),
Figures 2, 3
15
tF
Differential Skew (Same Channel)
|tDPLH - tDPHL|
tSK1
Skew Driver to Driver
(Same Device)
tSK2
RL = 100Ω, CL = 50pF, VCC = 3.3V
_______________________________________________________________________________________
3
MAX3030E–MAX3033E
SWITCHING CHARACTERISTICS—MAX3030E, MAX3032E
SWITCHING CHARACTERISTICS—MAX3031E, MAX3033E (continued)
(3V ≤ VCC ≤ 3.6V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +3.3V and TA = +25°C.)
PARAMETER
SYMBOL
Skew Part to Part
CONDITIONS
MIN
TYP
RL = 100Ω, CL = 50pF, VCC = 3.3V,
∆TMAX = +5°C
tSK3
Maximum Data Rate
MAX
UNITS
18
ns
2
Mbps
Driver Enable to Output High
tDZH
S2 closed, RL = 500Ω, CL = 50pF,
Figures 4, 5
100
ns
Driver Enable to Output Low
tDZL
S1 closed, RL = 500Ω, CL = 50pF,
Figures 4, 5
100
ns
Driver Disable Time from Low
tDLZ
S1 closed, RL = 500Ω, CL = 50pF,
Figures 4, 5
150
ns
Driver Disable Time from High
tDHZ
S2 closed, RL = 500Ω, CL = 50pF,
Figures 4, 5
150
ns
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 DI changes state.
Note 3: Only one output shorted at a time.
Note 4: This input current 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 ILEAK.
Typical Operating Characteristics
(VCC = +3.3V and TA = +25°C, unless otherwise noted.)
TA = 0°C
2
TA = +25°C
TA = +85°C
1
OUTPUT CURRENT
vs. TRANSMITTER OUTPUT HIGH VOLTAGE
MAX3030E toc02
150
150
125
OUTPUT CURRENT (mA)
OUTPUT CURRENT (mA)
3
100
50
100
75
50
25
0
0
0
30
60
90
OUTPUT CURRENT (mA)
4
200
MAX3030E toc01
4
OUTPUT CURRENT
vs. TRANSMITTER OUTPUT LOW VOLTAGE
MAX3030E toc03
DIFFERENTIAL OUTPUT VOLTAGE
vs. OUTPUT CURRENT
DIFFERENTIAL OUTPUT VOLTAGE (V)
MAX3030E–MAX3033E
±15kV ESD-Protected, 3.3V Quad
RS-422 Transmitters
120
0
0
1
2
3
OUTPUT LOW VOLTAGE (V)
4
0
1
2
3
OUTPUT HIGH VOLTAGE (V)
_______________________________________________________________________________________
4
±15kV ESD-Protected, 3.3V Quad
RS-422 Transmitters
60
TA = +25°C
40
TA = 0°C
20
2.0
15
10
2
3
4
NO RESISTIVE LOAD, CL = 200pF,
ALL FOUR
TRANSMITTERS
SWITCHING
1.5
1.0
0.5
0
0
1
0
0.1k
1k
10k
100k
1M
10M
100M
0.1k
1k
10k
100k
1M
SUPPLY VOLTAGE (V)
DATA RATE (bps)
DATA RATE (bps)
MAX3030E/MAX3032E
SUPPLY CURRENT vs. DATA RATE
MAX3031E/MAX3033E
SUPPLY CURRENT vs. DATA RATE
MAX3030E
DRIVER PROPAGATION DELAY
(LOW TO HIGH)
SUPPLY CURRENT (mA)
ALL FOUR TRANSMITTERS
LOADED AND SWITCHING
RL = 100Ω, CL = 200pF
110
100
10M
MAX3030E toc09
MAX3030E toc08
100
MAX3030E toc07
130
SUPPLY CURRENT (mA)
20
5
0
120
NO RESISTIVE LOAD, CL = 200pF,
ALL FOUR
TRANSMITTERS
SWITCHING
SUPPLY CURRENT (mA)
25
SUPPLY CURRENT (mA)
TA = +85°C
2.5
MAX3030E toc05
DRIVERS ENABLED
SUPPLY CURRENT (µA)
30
MAX3030E toc04
100
80
MAX3031E/MAX3033E
SUPPLY CURRENT vs. DATA RATE
MAX3030E/MAX3032E
SUPPLY CURRENT vs. DATA RATE
MAX3030E toc06
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
MAX3030E–MAX3033E
Typical Operating Characteristics (continued)
(VCC = +3.3V and TA = +25°C, unless otherwise noted.)
ALL FOUR TRANSMITTERS
LOADED AND SWITCHING
RL = 100Ω, CL = 200pF
DI_
1V/div
97
DIFFERENTIAL
OUTPUT
2V/div
94
91
90
80
88
0.1k
1k
10k
100k
1M
10M
100M
0.1k
1k
10k
100k
1M
DATA RATE (bps)
DATA RATE (bps)
MAX3030E
DRIVER PROPAGATION DELAY
(HIGH TO LOW)
MAX3031E
DRIVER PROPAGATION DELAY
(LOW TO HIGH)
MAX3030E toc10
10M
10ns/div
MAX3031E
DRIVER PROPAGATION DELAY
(HIGH TO LOW)
MAX3030E toc11
MAX3030E toc12
DI_
1V/div
DIFFERENTIAL
OUTPUT
2V/div
DIFFERENTIAL
OUTPUT
2V/div
DIFFERENTIAL
OUTPUT
2V/div
DI_
1V/div
DI_
1V/div
10ns/div
20ns/div
20ns/div
_______________________________________________________________________________________
5
MAX3030E–MAX3033E
±15kV ESD-Protected, 3.3V Quad
RS-422 Transmitters
Typical Operating Characteristics (continued)
(VCC = +3.3V and TA = +25°C, unless otherwise noted.)
ENABLE RESPONSE TIME
MAX3033E EYE DIAGRAM
MAX3030E toc13
MAX3030E toc14
ENABLE
1V/div
DO_+
1V/div
DIFFERENTIAL
OUTPUT
2V/div
DO_1V/div
20ns/div
100ns/div
Pin Description
PIN
MAX3030E/
MAX3031E
MAX3032E/
MAX3033E
1, 7, 9, 15
1, 7, 9, 15
2, 6, 10, 14
2, 6, 10, 14
3, 5, 11, 13
3, 5, 11, 13
FUNCTION
DI1, DI2,
DI3, DI4
Transmitter Inputs. When the corresponding transmitter is enabled, a low on DI_ forces
the noninverting output low and inverting output high. Similarly, a high on DI_ forces
noninverting output high and inverting output low.
DO1+, DO2+,
Noninverting RS-422 Outputs
DO3+, DO4+
DO1-, DO2-,
DO3-, DO4-
Inverting RS-422 Outputs
Transmitter Enable Input: Active HIGH. Drive EN HIGH to enable all transmitters. When
EN is HIGH, drive EN LOW to disable (three-state) all the transmitters. The transmitter
outputs are high impedance when disabled. EN is hot-swap protected (see the Hot
Swap section).
4
—
EN
8
8
GND
12
—
EN
Transmitter Enable Input: Active LOW. Drive EN LOW to enable all transmitters. When
EN is LOW, drive EN HIGH to disable all the transmitters. The transmitter outputs are
high impedance when disabled. EN is hot-swap protected (see the Hot Swap section).
EN1&2
Transmitter Enable Input for Channels 1 and 2. Drive EN1&2 HIGH to enable the
corresponding transmitters. Drive EN1&2 LOW to disable the corresponding
transmitters. The transmitter outputs are high impedance when disabled. EN1&2 is hotswap protected (see the Hot Swap section).
Transmitter Enable Input for Channels 3 and 4. Drive EN3&4 HIGH to enable the
corresponding transmitters. Drive EN3&4 LOW to disable the corresponding
transmitters. The transmitter outputs are high impedance when disabled. EN3&4 is hotswap protected (see the Hot Swap section).
—
6
NAME
4
—
12
EN3&4
16
16
VCC
Ground
Positive Supply; +3V ≤ VCC ≤ +3.6V. Bypass VCC to GND with a 0.1µF capacitor.
_______________________________________________________________________________________
±15kV ESD-Protected, 3.3V Quad
RS-422 Transmitters
CL
DI_+
DO_+
RL
2
VOD
RL
VOD
DI_
VOC
CL
RL
2
DI_-
DO_CL
Figure 1. Differential Driver DC Test Circuit
Figure 2. Differential Driver Propagation Delay and Transition
Time Test Circuit
3V
DI
1.5V
1.5V
0V
tDPHL
tDPLH
1/2 VO
DO_VO
DO_+
S1
RL
OUTPUT
UNDER TEST
CL
1/2 VO
VO
VDIFF 0V
-VO
VCC
S2
VDIFF = V (DO_+) - V (DO_-)
10%
90%
90%
10%
tF
tR
ENABLE SIGNAL IS ONE OF THE POSSIBLE
ENABLE CONFIGURATIONS (SEE TRUTH TABLE).
tSKEW = |tDPLH - tDPHL|
Figure 3. Differential Driver Propagation Delay and Transition
Waveform
Figure 4. Driver Enable/Disable Delays Test Circuit
3V
EN
1.5V
1.5V
0V
tDZL
tDLZ
VOL
1.5V OUTPUT NORMALLY LOW
VOH
OUTPUT NORMALLY HIGH
VOL + 0.3V
DI
GND
1.5V
DO_+
VCC
DO_-
A
A
VOH - 0.3V
0V
tDZH
tDHZ
ENABLE SIGNAL IS ONE OF THE POSSIBLE
ENABLE CONFIGURATIONS (SEE TRUTH TABLE).
Figure 5. Driver Enable/Disable Waveform
Figure 6. Short-Circuit Measurements
_______________________________________________________________________________________
7
MAX3030E–MAX3033E
Test Circuits and Timing Diagrams
MAX3030E–MAX3033E
±15kV ESD-Protected, 3.3V Quad
RS-422 Transmitters
Test Circuits and
Timing Diagrams (continued)
VCC
GND
DO_+
DI
DO_-
transmitter outputs of this product family are characterized for protection to ±15kV using the Human Body
Model. Other ESD test methodologies include
IEC10004-2 Contact Discharge and IEC1000-4-2 AirGap Discharge (formerly IEC801-2).
A
A
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 7. Power-Off Measurements
Detailed Description
The MAX3030E–MAX3033E are high-speed quad RS422 transmitters designed for digital data transmission
over balanced lines. They are designed to meet the
requirements of TIA/EIA-422-B and ITU-T V.11. The
MAX3030E–MAX3033E are available in two pinouts to
be compatible with both the 26LS31 and SN75174
industry-standard devices. Both are offered in 20Mbps
and 2Mbps baud rate. All versions feature a low-static
current consumption (ICC < 100µA) that makes them
ideal for battery-powered and power-conscious applications. The 20Mbps version has a maximum propagation delay of 16ns and a part-to-part skew less than
5ns, allowing these devices to drive parallel data. The
2Mbps version is slew-rate-limited to reduce EMI and
reduce reflections caused by improperly terminated
cables.
Outputs have enhanced ESD protection providing
±15kV tolerance. All parts feature hot-swap capability
that eliminates false transitions on the data cable during power-up or hot insertion.
±15kV ESD Protection
As with all Maxim devices, ESD-protection structures
are incorporated on all pins to protect against electrostatic discharges encountered during handling and
assembly. The driver outputs and receiver inputs have
extra protection against static electricity. Maxim’s engineers developed state-of-the-art structures to protect
these pins against ESD of ±15kV without damage. The
ESD structures withstand high ESD in all states: normal
operation and power-down. After an ESD event, the
MAX3030E–MAX3033E keep working without latchup.
ESD protection can be tested in various ways; the
8
Figure 8 shows the Human Body Model, and Figure 9
shows the current waveform it generates when discharged into 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.
RC
1MΩ
CHARGE-CURRENTLIMIT RESISTOR
HIGHVOLTAGE
DC
SOURCE
Cs
100pF
RD
1.5kΩ
DISCHARGE
RESISTANCE
DEVICE
UNDER
TEST
STORAGE
CAPACITOR
Figure 8. Human Body ESD Test Model
IP 100%
90%
Ir
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
AMPS
36.8%
10%
0
0
tRL
TIME
tDL
CURRENT WAVEFORM
Figure 9. Human Body Current Waveform
_______________________________________________________________________________________
±15kV ESD-Protected, 3.3V Quad
RS-422 Transmitters
MAX3030E–MAX3033E
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 inputs and outputs.
Therefore, after PC board assembly, the Machine
Model is less relevant to I/O ports.
VCC
6µs
TIMER
TIMER
Hot Swap
When circuit boards are plugged into a “hot” backplane, there can be disturbances to the differential signal levels that could be detected by receivers
connected to the transmission line. This erroneous data
could cause data errors to an RS-422 system. To avoid
this, the MAX3030E–MAX3033E 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 are
unable to drive the enable inputs of the MAX3030E–
MAX3033E (EN, EN, EN_) to defined logic levels.
Leakage currents from these high-impedance drivers,
of as much as 10µA, could cause the enable inputs of
the MAX3030E–MAX3033E to drift high or low.
Additionally, parasitic capacitance of the circuit board
could cause capacitive coupling of the enable inputs to
either GND or V CC . These factors could cause the
enable inputs of the MAX3030E–MAX3033E to drift to
levels that may enable the transmitter outputs. To avoid
this problem, the hot-swap input provides a method of
holding the enable inputs of the MAX3030E–MAX3033E
in the disabled state as VCC ramps up. This hot-swap
input is able to overcome the leakage currents and parasitic capacitances that can pull the enable inputs to
the enabled state.
Hot-Swap Input Circuitry
In the MAX3030E–MAX3033E, the enable inputs feature
hot-swap capability. At the input there are two NMOS
devices, M1 and M2 (Figure 10). When VCC is ramping
up from zero, an internal 6µs timer turns on M2 and sets
the SR latch, which also turns on M1. Transistors M2, a
2mA current sink, and M1, a 100µA current sink, pull EN
to GND through a 5.6kΩ resistor. M2 is designed to pull
the EN input to the disabled state against an external
parasitic capacitance of up to 100pF that is trying to
enable the EN input. After 6µs, the timer turns M2 off and
M1 remains on, holding the EN input low against threestate output leakages that might enable EN. M1 remains
on until an external source overcomes the required input
5.6kΩ
DE
(HOT SWAP)
EN
100µA
2mA
M1
M2
Figure 10. Simplified Structure of the Driver Enable Pin (EN)
3.3V
VCC
1kΩ
DO_+
DI_
(VCC OR GND)
0.1kΩ
50pF
DO_1kΩ
Figure 11. Differential Power-Up Glitch (Hot Swap)
current. At this time the SR latch resets and M1 turns off.
When M1 turns off, EN reverts to a standard, highimpedance CMOS input. Whenever VCC drops below
1V, the hot-swap input is reset. The EN1&2 and EN3&4
input structures are identical to the EN input. For the EN
input, there is a complementary circuit employing two
PMOS devices pulling the EN input to VCC.
Hot-Swap Line Transient
The circuit of Figure 11 shows a typical offset termination used to guarantee a greater than 200mV offset
when a line is not driven. The 50pF capacitor repre-
_______________________________________________________________________________________
9
MAX3030E–MAX3033E
±15kV ESD-Protected, 3.3V Quad
RS-422 Transmitters
sents the minimum parasitic capacitance that would
exist in a typical application. In most cases, more
capacitance exists in the system and reduces 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 12 and 13).
Operation of Enable Pins
The MAX3032E/MAX3033E are compatible with the
SN75174. EN1&2 controls transmitters 1 and 2, and EN
3&4 controls transmitters 3 and 4 (dual enable).
Typical Applications
The MAX3030E–MAX3033E offer optimum performance
when used with the MAX3094E/MAX3096 3.3V quad
differential line receivers. Figure 14 shows a typical RS422 connection for transmitting and receiving data.
The MAX3030E–MAX3033E family has two enable-functional versions.
The MAX3030E/MAX3031E are compatible with
26LS31, where the two enable signals control all four
transmitters (global enable).
VCC
1V/div
VCC
1V/div
DO_+ - DO_-
DO_+ - DO_-
DO_+
DO_+
DO_-
DO_1.0µs/div
4µs/div
Figure 12. Differential Power-Up Glitch (0.1V/µs)
Figure 13. Differential Power-Up Glitch (1V/µs)
Table 1. MAX3030E/MAX3031E Transmitter Controls
EN
EN
0
0
Active
Active
Active
Active
0
1
High-Z
High-Z
High-Z
High-Z
All transmitters disabled
1
0
Active
Active
Active
Active
All transmitters active
1
1
Active
Active
Active
Active
All transmitters active
TX1
TX2
TX3
TX4
MODE
All transmitters active
Table 2. MAX3032E/MAX3033E Transmitter Controls
10
EN1&2
EN3&4
TX1
TX2
TX3
TX4
0
0
0
1
1
1
MODE
High-Z
High-Z
High-Z
High-Z
All transmitters disabled
High-Z
High-Z
Active
Active
Tx 3 and 4 active
0
Active
Active
High-Z
High-Z
Tx 1 and 2 active
1
Active
Active
Active
Active
All transmitters active
______________________________________________________________________________________
±15kV ESD-Protected, 3.3V Quad
RS-422 Transmitters
MAX3094
DI1
D1
RT
R1
R1OUT
DI2
D2
RT
R2
R2OUT
DI3
D3
RT
R3
R3OUT
DI4
D4
RT
R4
R4OUT
EN
G
EN
G
VCC
MAX3030E–MAX3033E
MAX3030E/MAX3031E
GND
VCC
GND
Figure 14. Typical Connection of a Quad Transmitter and Quad Receiver as a Pair
______________________________________________________________________________________
11
MAX3030E–MAX3033E
±15kV ESD-Protected, 3.3V Quad
RS-422 Transmitters
VCC
VCC
GND
GND
EN1&2
EN
EN
EN3&4
DO1+
DI1
DO1-
DO1+
DI1
DO1-
DO2+
DI2
DO2-
DO2+
DI2
DO2-
DO3+
DI3
DO3-
DO3+
DI3
DO3-
DO4+
DI4
DO4-
DO4+
DI4
DO4-
MAX3030E/MAX3031E
MAX3032E/MAX3033E
Figure 15. MAX3030E/MAX3031E Functional Diagram
Figure 16. MAX3032E/MAX3033E Functional Diagram
Chip Information
TRANSISTOR COUNT: 1050
PROCESS: BiCMOS
12
______________________________________________________________________________________
±15kV ESD-Protected, 3.3V Quad
RS-422 Transmitters
N
E
H
INCHES
MILLIMETERS
MAX
MIN
0.069
0.053
0.010
0.004
0.014
0.019
0.007
0.010
0.050 BSC
0.150
0.157
0.228
0.244
0.016
0.050
MAX
MIN
1.35
1.75
0.10
0.25
0.35
0.49
0.19
0.25
1.27 BSC
3.80
4.00
5.80
6.20
0.40
SOICN .EPS
DIM
A
A1
B
C
e
E
H
L
1.27
VARIATIONS:
1
INCHES
TOP VIEW
DIM
D
D
D
MIN
0.189
0.337
0.386
MAX
0.197
0.344
0.394
MILLIMETERS
MIN
4.80
8.55
9.80
MAX
5.00
8.75
10.00
N MS012
8
AA
14
AB
16
AC
D
A
B
e
C
0 -8
A1
L
FRONT VIEW
SIDE VIEW
PROPRIETARY INFORMATION
TITLE:
PACKAGE OUTLINE, .150" SOIC
APPROVAL
DOCUMENT CONTROL NO.
21-0041
REV.
B
1
1
______________________________________________________________________________________
13
MAX3030E–MAX3033E
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
TSSOP4.40mm.EPS
MAX3030E–MAX3033E
±15kV ESD-Protected, 3.3V Quad
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.
14 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2002 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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