DS36C280TN
NSC DS36C280TN, DS36C280TMX, DS36C280TM, DS36C280N, DS36C280MX Datasheet
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DS36C280
Slew Rate Controlled CMOS EIA-RS-485 Transceiver
General Description
The DS36C280 is a low power differential bus/line trans-
ceiver designed to meet the requirements of RS-485 Stan-
dard for multipoint data transmission. In addition, it is com-
patible with TIA/EIA-422-B.
The slew ratecontrol feature allows the user to set the driver
rise and fall times by using an external resistor. Controlled
edge rates can reduce switching EMI.
The CMOS design offers significant power savings over its
bipolar andALS counterparts without sacrificing ruggedness
against ESD damage. The device is ideal for use in battery
powered or power conscious applications. I
CC
is specified at
500 µA maximum.
The driver and receiver outputs feature TRI-STATE
®
capabil-
ity.The driver outputs operate over the entire common mode
range of −7V to +12V. Bus contention or fault situations are
handled by a thermal shutdown circuit, which forces the
driver outputs into the high impedance state.
The receiver incorporates a fail safe circuit which guarantees
a high output state when the inputs are left open (Note 1) .
Features
n 100
%
RS-485 compliant
— Guaranteed RS-485 device interoperation
n Low power CMOS design: I
CC
500 µA max
n Adjustable slew rate control
— Minimizes EMI affects
n Built-in power up/down glitch-free circuitry
— Permits live transceiver insertion/displacement
n DIP and SOIC packages available
n Industrial temperature range: −40˚C to +85˚C
n On-board thermal shutdown circuitry
— Prevents damage to the device in the event of
excessive power dissipation
n Wide common mode range: −7V to +12V
n Receiver open input fail-safe (Note 1)
n
1
⁄
4
unit load (DS36C280): ≥128 nodes
n
1
⁄
2
unit load (DS36C280T): ≥64 nodes
n ESD (human body model): ≥2kV
Connection and Logic Diagram Truth Table
DRIVER SECTION
DE/RE* DI DO/RI DO*/RI*
HHH L
HLL H
LXZ Z
RECEIVER SECTION
DE/RE* RI-RI* RO
L ≥+0.2V H
L ≤−0.2V L
HX Z
L OPEN (Note 1) H
Note 1: Non-terminated, Open Inputs only
TRI-STATE
®
is a registered trademark of National Semiconductor Corporation.
DS012052-1
Order Number DS36C280TM, DS36C280TN
DS36C280M and DS36C280N
See NS Package Number M08A or N08E
July 1998
DS36C280 Slew Rate Controlled CMOS EIA-RS-485 Transceiver
© 1999 National Semiconductor Corporation DS012052 www.national.com
Absolute Maximum Ratings (Note 2)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Supply Voltage (V
CC
) +12V
Input Voltage (DE/RE*, & DI) −0.5V to (V
CC
+0.5V)
Common Mode (V
CM
)
Driver Output/Receiver Input
±
15V
Input Voltage (DO/RI, DO*/RI*)
±
14V
Receiver Output Voltage −0.5V to (V
CC
+0.5V)
Maximum Package Power Dissipation
@
+25˚C
M Package 1190 mV, derate 9.5 mW/˚C above +25˚C
N Package 794 mV, derate 6.0 mW/˚C above +25˚C
Storage Temperature Range −65˚C to +150˚C
Lead Temperature +260˚C
(Soldering 4 sec.)
Recommended Operating
Conditions
Min Typ Max Units
Supply Voltage (V
CC
) +4.75 +5.0 +5.25 V
Bus Voltage −7 +12 V
Operating Free Air Temperature (T
A
)
DS36C280T −40 +25 +85 ˚C
DS36C280 0 +25 +70 ˚C
Electrical Characteristics (Notes 3, 4)
Over Supply Voltage and Operating Temperature ranges, unless otherwise specified
Symbol Parameter Conditions Reference Min Typ Max Units
DIFFERENTIAL DRIVER CHARACTERISTICS
V
OD1
Differential Output Voltage I
O
= 0 mA (No Load)
(422)
(485)
1.5 5.0 V
V
OD0
Output Voltage I
O
= 0 mA 0 5.0 V
V
OD0*
Output Voltage (Output to GND) 0 5.0 V
V
OD2
Differential Output Voltage
(Termination Load)
R
L
=50Ω (422)
Figure 1
2.0 2.8 V
R
L
=27Ω (485) 1.5 2.3 5.0 V
∆V
OD2
Balance of V
OD2
R
L
=27Ωor 50Ω (Note 5) −0.2 0.1 +0.2 V
|V
OD2
−V
OD2*
| (422, 485)
V
OD3
Differential Output Voltage
(Full Load)
R1=54Ω,R2=375Ω
Figure 2
1.5 2.0 5.0 V
V
TEST
= −7V to +12V
V
OC
Driver Common Mode
Output Voltage
R
L
=27Ω (485)
Figure 1
0 3.0 V
R
L
=50Ω (422) 0 3.0 V
∆V
OC
Balance of V
OC
R
L
=27Ωor (Note 5) −0.2 +0.2 V
|V
OC
−V
OC*
|R
L
=50Ω (422, 485)
I
OSD
Driver Output Short-Circuit
Current
V
O
= +12V (485)
Figure 4
200 +250 mA
V
O
= −7V (485) −190 −250 mA
RECEIVER CHARACTERISTICS
V
TH
Differential Input High
Threshold Voltage
V
O
=V
OH
,I
O
= −0.4 mA
(Note 6)
(422, 485)
+0.035 +0.2 V
−7V ≤ V
CM
≤ +12V
V
TL
Differential Input Low
Threshold Voltage
V
O
=V
OL
,I
O
= 0.4 mA −0.2 −0.035 V
−7V ≤ V
CM
≤ +12V
V
HST
Hysteresis V
CM
=0V 70 mV
R
IN
Input Resistance −7V ≤ V
CM
≤ +12V DS36C280T 24 68 kΩ
R
IN
Input Resistance −7V ≤ V
CM
≤ +12V DS36C280 48 68 kΩ
I
IN
Line Input Current
(Note 8)
Other Input = 0V DS36C280 V
IN
= +12V 0 0.19 0.25 mA
DE=V
IL
,RE*=V
IL
V
IN
= −7V 0 −0.1 −0.2 mA
V
CC
= 4.75 to 5.25 DS36C280T V
IN
= +12V 0 0.19 0.5 mA
or 0V V
IN
= −7V 0 −0.1 −0.4 mA
I
ING
Line Input Current
Glitch (Note 8)
Other Input = 0V DS36C280 V
IN
= +12V 0 0.19 0.25 mA
DE=V
IL
,RE*=V
IL
V
IN
= −7V 0 −0.1 −0.2 mA
V
CC
= +3.0V DS36C280T V
IN
= +12V 0 0.19 0.5 mA
or 0V T
A
= 25˚C V
IN
= −7V 0 −0.1 −0.4 mA
I
B
Input Balance Test RS = 500Ω (422) (Note 10)
±
400 mV
V
OH
High Level Output Voltage I
OH
= −4 mA, V
ID
= +0.2V RO
Figure 11
3.5 4.6 V
V
OL
Low Level Output Voltage I
OL
= +4 mA, V
ID
= −0.2V 0.3 0.5 V
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Electrical Characteristics (Notes 3, 4) (Continued)
Over Supply Voltage and Operating Temperature ranges, unless otherwise specified
Symbol Parameter Conditions Reference Min Typ Max Units
RECEIVER CHARACTERISTICS
I
OSR
Short Circuit Current V
O
= GND RO 7 35 85 mA
I
OZR
TRI-STATE Leakage
Current
V
O
= 0.4V to 2.4V
±
1µA
DEVICE CHARACTERISTICS
V
IH
High Level Input Voltage
DE/RE*,
DI
2.0 V
CC
V
V
IL
Low Level Input Voltage GND 0.8 V
I
IH
High Level Input Current V
IH
=V
CC
2µA
I
IL
Low Level Input Current V
CC
= 5.0V
V
IL
=0V
−2 µA
V
CC
= +3.0V −2 µA
SR=0V SR −1 mA
I
CCR
Power Supply Current
(No Load)
Driver OFF, Receiver ON
V
CC
200 500 µA
I
CCD
Driver ON, Receiver OFF 200 500 µA
Switching Characteristics (Notes 4, 9, 11)
Over Supply Voltage and Operating Temperature ranges, unless otherwise specified
Symbol Parameter Conditions Reference Min Typ Max Units
DRIVER CHARACTERISTICS
t
PHLD
Differential Propagation
Delay High to Low
R
L
=54Ω,C
L
= 100 pF
Figures 5, 6
10 399 1000 ns
t
PLHD
Differential Propagation
Delay Low to High
10 400 1000 ns
t
SKD
Differential Skew 0 1 10 ns
|t
PHLD
−t
PLHD
|
t
r
Rise Time SR = Open 2870 ns
t
f
Fall Time 3070 ns
t
r
Rise Time SR = 100 kΩ 1590 ns
t
f
Fall Time 1640 ns
t
r
Rise Time SR = Short 100 337 1000 ns
t
f
Fall Time 100 348 1000 ns
t
PHZ
Disable Time High to Z C
L
=15pF
Figures 7, 8
1100 2000 ns
t
PLZ
Disable Time Low to Z
Figures 9, 10
500 800 ns
t
PZH
Enable Time Z to High C
L
= 100 pF
Figures 7, 8
300 500 ns
t
PZL
Enable Time Z to Low
Figures 9, 10
300 500 ns
RECEIVER CHARACTERISTICS
t
PHL
Propagation Delay
High to Low
C
L
=15pF
Figures 12, 13
30 210 400 ns
t
PLH
Propagation Delay
Low to High
30 190 400 ns
t
SK
Skew, |t
PHL
−t
PLH
| 0 20 50 ns
t
PLZ
Output Disable Time C
L
=15pF
Figures 14, 15, 16
50 150 ns
t
PHZ
55 150 ns
t
PZL
Output Enable Time 40 150 ns
t
PZH
45 150 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 table of “Electrical Characteristics” specifies conditions of device operation.
Note 3: Current into device pins is definedas positive. Current out of device pins is defined as negative. All voltages are referenced to ground except V
OD1
and V
OD2
.
Note 4: All typicals are given for: V
CC
= +5.0V, T
A
= + 25˚C.
Note 5: Delta |V
OD2
| and Delta |V
OC
| are changes in magnitude of V
OD2
and V
OC
, respectively, that occur when input changes state.
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