NSC DS8923AN

DS8922/DS8922A/DS8923A TRI-STATE ®
RS-422 Dual Differential Line Driver and Receiver Pairs
General Description
The DS8922/22A and DS8923A are Dual Differential Line
Driver and Receiver pairs. These devices are designed specifically for applications meeting the ST506, ST412 and
ESDI Disk Drive Standards. In addition, the devices meet the
requirements of the EIA Standard RS-422.
These devices offer an input sensitivity of 200 mV over a
± 7V common mode operating range. Hysteresis is incorporated (typically 70 mV) to improve noise margin for slowly
changing input waveforms. An input fail-safe circuit is provided such that if the receiver inputs are open the output assumes the logical one state.
The DS8922A and DS8923A drivers are designed to provide
unipolar differential drive to twisted pair or parallel wire transmission lines. Complementary outputs are logically ANDed
and provide an output skew of 0.5 ns (typ.) with propagation
delays of 12 ns.
Both devices feature TRI-STATE outputs. The DS8922/22A
have independent control functions common to a driver and
receiver pair. The DS8923A has separate driver and receiver
control functions.
Power up/down circuitry is featured which will TRI-STATE
the outputs and prevent erroneous glitches on the transmission lines during system power up or power down operation.
The DS8922/22A and DS8923A are designed to be compatible with TTL and CMOS.
Features
n
n
n
n
n
n
n
n
n
n
12 ns typical propagation delay
Output skew — ± 0.5 ns typical
Meets the requirements of EIA Standard RS-422
Complementary Driver Outputs
High differential or common-mode input voltage ranges
of ± 7V
± 0.2V receiver sensitivity over the input voltage range
Receiver input fail-safe circuitry
Receiver input hysteresis — 70 mV typical
Glitch free power up/down
TRI-STATE outputs
Connection Diagrams
DS8922A Dual-In-Line
DS008511-1
Order Number DS8922M, DS8922N,
DS8922AM or DS8922AN
See NS Package Number M16A or N16E
TRI-STATE ® is a registered trademark of National Semiconductor Corp.
© 1998 National Semiconductor Corporation
DS008511
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DS8922/DS8922A/DS8923A TRI-STATE RS-422 Dual Differential Line Driver and Receiver Pairs
June 1998
Connection Diagrams
(Continued)
DS8923A Dual-In-Line
DS008511-2
Order Number DS8923AM, DS8923AN,
See NS Package Number M16A or N16E
Truth Tables
DS8922/22A
EN1
EN2
RO1
RO2
DO1
DO2
0
0
ACTIVE
ACTIVE
ACTIVE
ACTIVE
1
0
HI-Z
ACTIVE
HI-Z
ACTIVE
0
1
ACTIVE
HI-Z
ACTIVE
HI-Z
1
1
HI-Z
HI-Z
HI-Z
HI-Z
DS8923A
DEN
REN
RO1
RO2
DO1
DO2
0
0
ACTIVE
ACTIVE
ACTIVE
ACTIVE
1
0
ACTIVE
ACTIVE
HI-Z
HI-Z
0
1
HI-Z
HI-Z
ACTIVE
ACTIVE
1
1
HI-Z
HI-Z
HI-Z
HI-Z
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2
Absolute Maximum Ratings (Note 1)
N Package
1450 mW
Derate M Package 10.4 mW/˚C above +25˚C
Derate N Package 11.6 mW/˚C above +25˚C
Storage Temperature Range
−65˚C to +165˚C
Lead Temp. (Soldering, 4 seconds)
260˚C
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Supply Voltage
7V
Drive Input Voltage
−0.5V to +7V
Output Voltage
5.5V
Receiver Output Sink Current
50 mA
± 10V
Receiver Input Voltage
± 12V
Differential Input Voltage
Maximum Package Power Dissipation @ +25˚C
M Package
1300 mW
Recommended Operating
Conditions
Min
4.5
0
Supply Voltage
Temperature (TA)
Max
5.5
70
Units
V
˚C
DS8922/22A and DS8923A Electrical Characteristics(Notes 2, 3, 4)
Symbol
Conditions
Min
Typ
Max
Units
−200
± 35
+200
mV
RECEIVER
VTH
−7V ≤ VCM ≤ +7V
VHYST
15
70
4.0
6.0
IIN
−7V ≤ VCM ≤ +7V
V IN = −7V, +7V (Other Input = GND)
VIN = 10V
VOH
V
2.5
VOL
VIN = −10V
CC = MIN, IOH = − 400 µA
V CC = MAX, IOL = 8 mA
ISC
V
CC
VOH
V
CC
VOL
V
CC
IOFF
V
CC
RIN
= MAX, VOUT = 0V
−15
= MIN, IOH = −20 mA
= MIN, IOL = +20 mA
= 0V, VOUT = 5.5V
2.5
mV
kΩ
3.25
mA
−3.25
mA
0.5
V
−100
mA
V
DRIVER
V
|VT|–| VT |
VT
V
100
µA
0.4
V
2.0
V
|VOS– VOS |
ISC
0.5
V
CC
= MAX, VOUT = 0V
−30
0.4
V
−150
mA
DRIVER and RECEIVER
VOUT = 2.5V
VOUT = 0.4V
50
µA
VCC = MAX
−50
µA
VCC = MAX
ACTIVE
76
mA
TRI-STATE
78
mA
0.8
V
IOZ
TRI-STATE
Leakage
ICC
DRIVER and ENABLE INPUTS
VIH
2.0
V
VIL
IIL
V
CC
IIH
V
CC
II
V
CC
VCL
V
CC
= MAX, VIN = 0.4V
= MAX, VIN = 2.7V
= MAX, VIN = 7.0V
= MIN, IIN = −18 mA
−40
3
−200
µA
20
µA
100
µA
−1.5
V
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Receiver Switching Characteristics
(Figures 1, 2, 3)
Parameter
Conditions
Min
Typ
Max
Units
8922
8922A/23A
12
22.5
20
12
22.5
20
ns
0.5
5
3.5
ns
0.5
3.0
2.0
ns
TpZL
CL = 30 pF
CL = 15 pF S2 Open
CL = 15 pF S1 Open
CL = 30 pF S2 Open
TpZH
CL = 30 pF S1 Open
TpLH
TpHL
|TpLH–T pHL|
Skew (Channel to Channel)
TpLZ
TpHZ
CL = 30 pF
CL = 30 pF
CL = 30 pF
ns
15
ns
15
ns
20
ns
20
ns
Driver Switching Characteristics
Parameter
Conditions
Min
SINGLE ENDED CHARACTERISTICS (Figures 4, 5, 6, 8)
CL = 30 pF
TpLH
TpHL
TTLH
TTHL
|TpLH–T pHL|
Skew
Typ
Max
Units
8922
8922A/23A
12
15
15
CL = 30 pF
CL = 30 pF
CL = 30 pF
12
15
15
ns
5
10
10
ns
5
10
10
CL = 30 pF
CL = 30 pF (Note 5)
0.5
Skew (Channel to Channel)
ns
ns
ns
0.5
5
3.5
ns
0.5
3.0
2.0
ns
15
ns
15
ns
TpZL
CL = 30 pF
CL = 30 pF
CL = 30 pF
20
ns
TpZH
CL = 30 pF
20
ns
TpLZ
TpHZ
DIFFERENTIAL SWITCHING CHARACTERISTICS (Note 6), (Figure 4)
TpLH
CL = 30 pF
TpHL
|TpLH–T pHL|
CL = 30 pF
CL = 30 pF
12
15
15
12
15
15
ns
ns
0.5
6.0
2.75
ns
Note 1: “Absolute Maximum Ratings” are those values beyond which the safety of the device cannot be guaranteed. They are not meant to imply that the device
should be operated at these limits. The Table of “Electrical Characteristics” provides conditions for actual device operation.
Note 2: All currents into device pins are shown as positive values; all currents out of the device are shown as negative; all voltages are referenced to ground unless
otherwise specified. All values shown as max or min are classified on absolute value basis.
Note 3: All typical values are VCC = 5V, TA = 25˚C.
Note 4: Only one output at a time should be shorted.
Note 5:
Difference between complementary outputs at the 50% point.
Note 6: Differential Delays are defined as calculated results from single ended rise and fall time measurements. This approach in establishing AC performance
specifications has been taken due to limitations of available Automatic Test Equipment (ATE).
The calculated ATE results assume a linear transition between measurement points and are a result of the following equations:
Where:
Tcp = Crossing Point
Tra, Trb, Tfa and Tfb are time measurements with respect to the input.
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Switching Time Waveforms
DS008511-3
AC Test Circuits and Switching Waveforms
DS008511-4
FIGURE 1.
DS008511-5
FIGURE 2.
5
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AC Test Circuits and Switching Waveforms
(Continued)
DS008511-6
S1
S2
S3
TPLZ
Closed
Open
+2.5V
TPHZ
Open
Closed
−2.5V
TPZL
Closed
Open
+2.5V
TPZH
Open
Closed
−2.5V
FIGURE 3.
DS008511-7
FIGURE 4.
DS008511-8
FIGURE 5.
DS008511-9
FIGURE 6.
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AC Test Circuits and Switching Waveforms
(Continued)
DS008511-10
FIGURE 7.
DS008511-13
FIGURE 8.
Typical Performance Characteristics
(DS8923A)
Driver VOH vs IOH
vs Temperature
Driver VOH vs IOH vs VCC
DS008511-15
DS008511-14
Driver VOL vs IOL
vs Temperature
Driver VOL vs IOL vs VCC
DS008511-17
DS008511-16
7
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Typical Performance Characteristics
(DS8923A) (Continued)
Receiver VOH vs IOH
vs Temperature
Receiver VOH vs IOH vs VCC
DS008511-19
DS008511-18
Receiver VOL vs IOL
vs Temperature
Receiver VOL vs IOL vs VCC
DS008511-21
DS008511-20
Driver Differential Propagation
Delay vs Temperature
Driver Differential Propagation
Delay vs VCC
DS008511-22
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DS008511-23
8
Typical Performance Characteristics
(DS8923A) (Continued)
Receiver Propagation
Delay vs Temperature
Receiver Propagation
Delay vs VCC
DS008511-24
Driver VOD vs Temperature
DS008511-25
Driver VOD vs VCC
DS008511-26
Driver VOD vs RL
DS008511-27
Driver Differential Transition
Time vs Temperature
DS008511-28
DS008511-29
9
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Typical Performance Characteristics
(DS8923A) (Continued)
Driver Differential Transition
Time vs VCC
Supply Current vs
Temperature
DS008511-31
DS008511-30
Supply Current vs V
ICC vs Driver Switching Frequency
CC
DS008511-32
Driver Short Circuit Current
vs Temperature
DS008511-33
Driver Short Circuit
Current vs VCC
DS008511-34
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DS008511-35
10
Typical Performance Characteristics
(DS8923A) (Continued)
Receiver Short Circuit
Current vs Temperature
Receiver Short Circuit
Current vs VCC
DS008511-36
DS008511-37
Typical Applications
ESDI Application
DS008511-11
11
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Typical Applications
(Continued)
ST504 and ST412 Applications
DS008511-12
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Physical Dimensions
inches (millimeters) unless otherwise noted
SO Package (M)
Order Number DS8922M, DS8922AM, or DS8923AM
NS Package Number M16A
Molded Dual-In-Line Package (N)
Order Number DS8922N, DS8922AN, or DS8923AN
NS Package Number N16E
13
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DS8922/DS8922A/DS8923A TRI-STATE RS-422 Dual Differential Line Driver and Receiver Pairs
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2. A critical component in any component of a life support
1. Life support devices or systems are devices or sysdevice or system whose failure to perform can be reatems which, (a) are intended for surgical implant into
sonably expected to cause the failure of the life support
the body, or (b) support or sustain life, and whose faildevice or system, or to affect its safety or effectiveness.
ure to perform when properly used in accordance
with instructions for use provided in the labeling, can
be reasonably expected to result in a significant injury
to the user.
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