NSC DS96172CN

DS96172/DS96174
RS-485/RS-422 Quad Differential Line Drivers
General Description
Features
The DS96172 and DS96174 are high speed quad differential
line drivers designed to meet EIA Standard RS-485. The devices have TRI-STATE ® outputs and are optimized for balanced multipoint data bus transmission at rates up to
10 Mbps. The drivers have wide positive and negative common mode range for multipoint applications in noisy environments. Positive and negative current-limiting is provided
which protects the drivers from line fault conditions over a
+12V to −7.0V common mode range. A thermal shutdown
feature is also provided and occurs at junction temperature
of approximately 160˚C. The DS96172 features an active
high and active low Enable, common to all four drivers. The
DS96174 features separate active high Enables for each
driver pair. Compatible RS-485 receivers, transceivers, and
repeaters are also offered to provide optimum bus performance. The respective device types are DS96173,
DS96175, DS96176 AND DS96177.
n
n
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n
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n
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Meets EIA Standard RS-485 and RS-422A
Monotonic differential output switching
Transmission rate to 10 Mbs
TRI-STATE outputs
Designed for multipoint bus transmission
Common mode output voltage range: −7V to +12V
Operates from single +5V supply
Thermal shutdown protection
DS96172/DS96174 are lead and function compatible
with the SN75172/75174 or the AM26LS31/MC3487
respectively
Connection Diagrams
16-Lead DIP
DS96172
16-Lead DIP
DS96174
DS009626-1
Top View
DS009626-2
Top View
Order Number DS96172CN or DS96174CN
See NS Package Number N16E
TRI-STATE ® is a registered trademark of National Semiconductor Corporation.
© 1998 National Semiconductor Corporation
DS009626
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DS96172/DS96174 RS-485/RS-422 Quad Differential Line Drivers
June 1998
Absolute Maximum Ratings (Note 2)
N-Molded Package
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Storage Temperature Range
Molded DIP
Operating Temperature Range
Lead Temperature
Molded DIP (soldering, 10
sec.)
Supply Voltage
Enable Input Voltage
Maximum Power Dissipation
(Note 1)
1.98W
Recommended Operating
Conditions
−65˚C to +150˚C
0˚C to +70˚C
Supply Voltage (VCC)
Common Mode Output
Voltage (VOC)
Output Current HIGH (IOH)
Output Current LOW (IOL)
Operating Temperature (TA)
265˚C
7V
5.5V
Min
4.75
Typ
5
Max
5.25
Units
V
25
+12
−60
60
70
V
mA
mA
˚C
−7
0
Note 1: Derate molded DIP package 16mW/˚C above 25˚C.
25˚C
Electrical Characteristics (Notes 3, 4)
over recommended temperature and supply voltage ranges, unless otherwise specified
Symbol
Parameter
VIH
Input Voltage HIGH
VIL
Input Voltage LOW
Conditions
Min
Typ
Max
Units
0.8
V
2
V
VOH
Output Voltage HIGH
IOH = −20 mA
3.1
V
VOL
Output Voltage LOW
IOL = 20 mA
0.8
V
VIC
Input Clamp Voltage
II = −18 mA
|VOD1|
Differential Output Voltage
IO = 0 mA
|VOD2|
Differential Output Voltage
∆|VOD|
Change in Magnitude of Differential
−1.5
V
6
V
RL = 54Ω, Figure 1
1.5
2
V
RL = 100Ω, Figure 1
2
2.3
V
RL = 54Ω or 100Ω, Figure 1
± 0.2
V
Output Voltage (Note 5)
VOC
Common Mode Output Voltage (Note 6)
∆|VOC|
Change in Magnitude of Common Mode
RL = 54Ω, Figure 1
3
V
± 0.2
V
± 100
± 200
µA
Output Voltage (Note 5)
IO
Output Current with Power Off
VCC = 0V, VO = −7.0V to 12V
IOZ
High Impedance State Output Current
VO = −7.0V to 12V
IIH
Input Current HIGH
VI = 2.7V
20
µA
IIL
Input Current LOW
VI = 0.5V
−100
µA
IOS
Short Circuit Output Current
VO = −7.0V
−250
(Note 7)
VO = 0V
−150
VO = VCC
150
± 50
VO = 12V
ICC
Supply Current (All Drivers)
No Load
µA
mA
250
Outputs Enabled
50
70
Output Disabled
50
60
mA
Switching Characteristics
VCC = 5V, TA = 25˚C
Symbol
Parameter
tDD
Differential Output Delay Time
tTD
Differential Output Transition Time
tPLH
Propagation Delay Time,
Conditions
RL = 60Ω, Figure 2
RL = 27Ω, Figure 3
Min
Typ
Max
Units
15
25
ns
15
25
ns
12
20
ns
12
20
ns
Low-to-High Level Output
tPHL
Propagation Delay Time,
High-to-Low Level Output
tPZH
Output Enable Time to High Level
RL = 110Ω, Figure 4
30
45
ns
tPZL
Output Enable Time to Low Level
RL = 110Ω, Figure 5
30
45
ns
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2
Switching Characteristics
(Continued)
VCC = 5V, TA = 25˚C
Typ
Max
Units
tPHZ
Symbol
Output Disable Time from High Level
Parameter
RL = 110Ω, Figure 4
Conditions
Min
25
35
ns
tPLZ
Output Disable Time from Low Level
RL = 110Ω, Figure 5
30
45
ns
Note 2: “Absolute Maximum Ratings” are those values beyond which the safety of the device cannot be guaranteed. They are not meant to imply that the devices
should be operated at these limits. The tables of “Electrical Characteristics” provide conditions for actual device operation.
Note 3: Unless otherwise specified min/max limits apply across the 0˚C to +70˚C range for the DS96172/DS96174. All typicals are given for VCC = 5V and TA = 25˚C.
Note 4: All currents into the device pins are positive; all currents out of the device pins are negative. All voltages are referenced to ground unless otherwise specified.
Note 5: ∆ |VOD| and ∆|VOC| are the changes in magnitude of VOD and VOC respectively, that occur when the input is changed from a high level to a low level.
Note 6: In EIA Standards RS-422A and RS-485, VOC, which is the average of the two output voltages with respect to ground, is called output offset voltage, VOS.
Note 7: Only one output at a time should be shorted.
Parameter Measurement Information
DS009626-4
FIGURE 1. Differential and Common Mode Output Voltage
DS009626-5
DS009626-6
FIGURE 2. Differential Output Delay and Transition Times
DS009626-7
DS009626-8
FIGURE 3. Propagation Delay Times
3
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Parameter Measurement Information
(Continued)
DS009626-10
DS009626-9
FIGURE 4. tPZH and tPHZ
DS009626-12
DS009626-11
FIGURE 5. tPZL and tPLZ
Note 8: The input pulse is supplied by a generator having the following characteristics: PRR = 1.0 MHz, duty cycle = 50%, tr ≤ 5.0 ns, tf ≤ 5.0 ns, ZO = 50Ω.
Note 9: CL includes probe and jig capacitance.
Note 10: DS96172 with active high and active low Enables is shown here. DS96174 has active high Enable only.
Note 11: To test the active low Enable E of DS96172, ground E and apply an inverted waveform to E . DS96174 has active high Enable only.
Function Tables
DS96174
DS96172
Input
Enables
Outputs
Input
Enable
Outputs
A
E
E
Y
Z
H
H
X
H
L
H
H
H
L
L
H
X
L
H
L
H
L
H
H
X
L
H
L
X
L
Z
Z
L
X
L
L
H
X
L
H
Z
Z
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Y
H = High Level
X = Immaterial
L = Low Level
Z = High Impedance (off)
4
Z
Typical Application
DS009626-13
Note: The line length should be terminated at both ends in its characteristic impedance.
Stub lengths off the main line should be kept as short as possible.
FIGURE 6.
5
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DS96172/DS96174 RS-485/RS-422 Quad Differential Line Drivers
Physical Dimensions
inches (millimeters) unless otherwise noted
Molded Dual-In-Line Package (N)
Order Number DS96172CN or DS96174CN
NS Package Number N16E
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