MAX3158EPI [MAXIM]
High CMRR RS-485 Transceiver with 【60V Isolation; 高共模抑制比RS - 485收发器，具有± 60V隔离
| 型号： | MAX3158EPI |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | High CMRR RS-485 Transceiver with 【60V Isolation |
| 文件： | 总14页 (文件大小：305K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
19-2778; Rev 0; 2/03
High CMRR RS-485 Transceiver
with ±±60 ꢀsolation
General Description
Features
The MAX3158 is a high CMRR RS-485/RS-422 data-com-
munications interface providing ±±60 isoꢀation in a
hybrid microcircuit. A singꢀe +50 suppꢀy on the ꢀogic side
powers both sides of the interface, with externaꢀ 1660
capacitors transferring power from the ꢀogic side to the
isoꢀated side. Each MAX3158 contains one transmitter
and one receiver and is guaranteed to operate at data
rates up to 256kbps. Drivers are short-circuit current ꢀim-
ited and protected against excessive power dissipation
by thermaꢀ shutdown circuitry that pꢀaces the driver out-
puts into a high-impedance state. The receiver input has
a faiꢀ-safe feature that guarantees a ꢀogic-high receiver
output if the inputs are open, shorted, or connected to a
terminated transmission ꢀine with aꢀꢀ drivers disabꢀed.
ꢀ ±±60V IsolateVꢀlalV ꢁatꢂrlꢃt
ꢀ +50VSiꢁgotVSuppoy
ꢀ Lsw-CsIaVRtpolꢃtmtꢁaVrsꢂVOpas- Isolate
TꢂlꢁIꢃtivtꢂI
ꢀ TꢂutVFlio-SlrtVRtꢃtivtꢂVWhiotVMliꢁaliꢁiꢁg
E A/T A-485VCsmpoilꢁꢃt
ꢀ Piꢁ-StotꢃalbotVFuoo/Hlor-ꢀupotxVOptꢂlaisꢁ
ꢀ PhlItVCsꢁaꢂsoIVasVCsꢂꢂtꢃaVrsꢂVTwiIate-Pliꢂ
RtvtꢂIlo
ꢀ 25µAVLsw-PswtꢂVShuaeswꢁVMset
ꢀ ThtꢂmloVShuaeswꢁVrsꢂVꢀꢂivtꢂVOvtꢂosleVPꢂsatꢃaisꢁ
ꢀ 28-PiꢁVSSOPVPlꢃklgt
The MAX3158 typicaꢀꢀy draws 25mA of suppꢀy current
when unꢀoaded or when fuꢀꢀy ꢀoaded with the driver dis-
abꢀed. Suppꢀy current drops to 25µA when the device is
pꢀaced in shutdown mode. The device is pin seꢀectabꢀe
between haꢀf- and fuꢀꢀ-dupꢀex mode and aꢀso features
an independentꢀy programmabꢀe receiver and transmit-
ter output phase through separate pins. The MAX3158
is a ꢀow-cost repꢀacement for opto-isoꢀated trans-
ceivers. For fuꢀꢀy isoꢀated RS-485/RS-422 transceivers,
refer to the MAX1486 famiꢀy data sheet.
ꢀ Sotw-Rlat-LimiateVRteuꢃteVEM
Ordering ꢀnformation
PART
TEMPVRANGE
6°C to +76°C
6°C to +76°C
-46°C to +85°C
-46°C to +85°C
P N-PACKAGE
28 SSOP
MAX3158CAI
MAX3158CPI
MAX3158EAI
MAX3158EPI
28 PDIP
________________________Applications
28 SSOP
Industriaꢀ Controꢀs
Teꢀecommunications
28 PDIP
Leveꢀ Transꢀators
Locaꢀ Area Networks
Pin Configurations appear at end of data sheet.
Typical Operating Circuit
V
CC
0.1µF
V
ISOVCC
CC
C3
1µF
H/F
TXP
A
RXP
B
Y
RS-485
NODE
RT = 100Ω
MICRO
DE
DI
Z
MAX3158
YR
ZR
AR
BR
RE
RO
RG
GND
C1LO C1HI C2LO C2HI ISOCOM
60V
C4
10nF
C1
C2
GND OFFSET
0.047µF 0.047µF
REMOTE GND
________________________________________________________________ Maxim Integrated Products
1
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.
High CMRR RS-485 Transceiver
with ±±60 ꢀsolation
ABSOLUTEVMAX MUMVRAT NGS
(Aꢀꢀ voꢀtages referenced to GND, unꢀess otherwise noted.)
Suppꢀy 0oꢀtage (0 ).............................................................+70
CC
Charge-Pump Capacitance Low
(C1LO, C2LO) .........................................-6.30 to (0
Charge-Pump Capacitance High (C1HI, C2HI) Reꢀative
to Cabꢀe Ground (ISOCOM) .............-6.30 to (ISO0CC + 6.30)
Continuous Power Dissipation (T = +76°C)
Cabꢀe Ground (ISOCOM) ....................................................±750
Isoꢀated Suppꢀy ISO0CC Reꢀative to Cabꢀe Ground
(ISOCOM) ...........................................................................+70
Digitaꢀ Input, Output 0oꢀtage
+ 6.30)
CC
A
(DI, DE, RE, TXP, RXP, RO).....................-6.30 to (0
Digitaꢀ Inputs (H/F) Reꢀative to Cabꢀe Ground
(ISOCOM) .........................................-6.30 to (ISO0CC + 6.30)
Driver Output 0oꢀtage (ꢂ, ꢃ) Reꢀative to Cabꢀe Ground
(ISOCOM)............................................................-80 to +12.50
Receiver Input 0oꢀtage (A, ꢄ) Reꢀative to Cabꢀe Ground
(ISOCOM)............................................................-80 to +12.50
Termination Connections (ꢂR, ꢃR, AR, ꢄR) Reꢀative to Cabꢀe
Ground (ISOCOM)...............................................-80 to +12.50
+ 6.30)
28-Pin SSOP (derate 16.8mW/°C above +76°C) ..........8±6mW
28-Pin PDIP (derate 14.3mW/°C above +76°C)..........1143mW
Operating Temperature Ranges
MAX3158C_I .......................................................6°C to +76°C
MAX3158E_I ....................................................-46°C to +85°C
Junction Temperature......................................................+156°C
Storage Temperature Range ............................-±5°C to +1±6°C
Lead Temperature (soꢀdering, 16s) ................................+366°C
CC
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.
ELECTR CALVCHARACTER ST CS
CC
(0
= +50 ±5ꢁ, ꢂR = ꢃR = AR = ꢄR = ISOCOM, C1 = C2 = 6.647µF, C3 = C4 = 1µF, T = T
to T
, unꢀess otherwise noted.
MAX
A
MIN
Typicaꢀ vaꢀues are at 0 = +50 and T = +25°C.) (Note 1)
CC
A
PARAMETER
SYMBOL
CONꢀ T ONS
M N
TYP
MAX
UN TS
ꢀR 0ER
Differential Driver Output,
No Load
V
V
Figure 1, R = 10MΩ
6
V
V
OD1
OD2
Figure 1, R = 50Ω (RS-422)
Figure 1, R = 27Ω (RS-485)
2.0
1.5
Differential Driver Output,
Loaded
Change in Magnitude of
Differential Output Voltage
(Note 2)
∆V
Figure 1, R = 50Ω or R = 27Ω
0.2
3.5
0.2
V
V
V
V
OD
Figure 1, R = 50Ω or R = 27Ω,
Driver Common-Mode Voltage
V
OC
V
relative to ISOCOM
OC
Change in Magnitude of
Common-Mode Voltage
(Note 2)
∆V
Figure 1, R = 50Ω or R = 27Ω
OC
DE, DI, RE, TXP, RXP, relative to GND,
H/F relative to ISOCOM
Input High Voltage
V
2.0
IH
DE, DI, RE, TXP, RXP, relative to GND,
H/F relative to ISOCOM
Input Low Voltage
DI Input Hysteresis
V
0.8
V
IL
V
100
mV
HYS
2
_______________________________________________________________________________________
High CMRR RS-485 Transceiver
with ±±60 ꢀsolation
ELECTR CALVCHARACTER ST CSV(ꢃsꢁaiꢁute)
CC
(V
= +5V 5ꢀ, YR = ꢁR = ꢂR = ꢃR = ISOCOM, C1 = C2 = 0.047ꢄF, C3 = C4 = 1ꢄF, T = T
to T
, unless otherwise noted.
MꢂX
ꢂ
MIN
Typical values are at V = +5V and T = +25°C.) (Note 1)
CC
ꢂ
PARAMETER
SYMBOL
CONꢀ T ONS
M N
TYP
MAX
2
UN TS
I
I
DE, DI, RE
H/F, TXP, RXP internal pulldown
DE = GND, V = GND or 5.25V, -7V ≤ (V
IN1
IN2
Input Current
ꢄꢂ
10
40
-
-
-
-
CC
IN
IN
IN
IN
-5.0
+8.0
+1.0
+8.0
+1.0
V
) ≤ +12V, ꢂR = ꢃR = ISOCOM
ISOCOM
Input Current (ꢂ and ꢃ)
I
mꢂ
IN3
DE = GND, V
V
= GND or 5.25V, -7V ≤ (V
CC
-0.58
-5.0
) ≤ +12V, ꢂR open, ꢃR open
ISOCOM
DE = GND, V
V
= GND or 5.25V, -7V ≤ (V
CC
) ≤ +12V, YR = ꢁR = ISOCOM
ISOCOM
Output Leakage (Y and ꢁ)
Full Duplex
I
O
mꢂ
mꢂ
mV
DE = GND, V
V
= GND or 5.25V, -7V ≤ (V
CC
-0.58
-250
) ≤ +12V, YR open, ꢁR open
ISOCOM
I
I
V
V
- 7V ≤ V
- 7V ≤ V
≤ V
≤ V
OSD1
ISOCOM
ISOCOM
OUT
OUT
ISOVCC
ISOCOM
Driver Short-Circuit Output
Current (Note 3)
+ 12V
250
-50
OSD2
RECE 0ER
Receiver Differential Threshold
Voltage
V
-7V ≤ V
- V
≤ +12V
-200
-125
25
TH
CM
ISOCOM
Receiver Input Hysteresis
∆V
mV
V
TH
Receiver Output High Voltage
Receiver Output Low Voltage
V
I
I
= -4mꢂ, V = -50mV
V
- 1.5
CC
OH
O
O
ID
V
V
= 4mꢂ, V = -200mV
0.4
1
OL
ID
Three-State Output Current at
Receiver
I
0.4V ≤ V ≤ 2.4V
ꢄꢂ
kΩ
mꢂ
OꢁR
O
-7V ≤ V
ISOCOM
- V
≤ +12V, ꢂR = ꢃR =
≤ +12V, ꢂR open,
CM
ISOCOM
ISOCOM
1.5
Receiver Input Resistance
R
IN
-7V ≤ V
ꢃR open
- V
CM
12
7
Receiver Output Short-Circuit
Current
I
0V ≤ V
≤ V
100
OSR
RO
CC
SUPPLYVCURRENT
Supply Current
I
No load, RE = DE = DI = GND or V
25
25
85
mꢂ
ꢄꢂ
CC
CC
DE = GND, RE = V , V
= GND
60
CC ISOCOM
Supply Current in Shutdown
Mode
I
SHDN
DE = GND, RE = V , V
=
60V
650
CC ISOCOM
DE = GND, RE = V
| ISOCOM leakage | ≤ 650ꢄꢂ
,
CC
Maximum Ground Differential
∆V
60
V
GND
_______________________________________________________________________________________
3
High CMRR RS-485 Transceiver
with ±±60 ꢀsolation
SW TCH NGVCHARACTER ST CS
CC
(V = +5V 5ꢀ, YR = ꢁR = ꢂR = ꢃR = ISOCOM, C1 = C2 = 0.047ꢄF, C3 = C4 = 1ꢄF. Typical values are at V = +5V and T = +25°C.)
CC
ꢂ
PARAMETER
SYMBOL
CONꢀ T ONS
M N
TYP
MAX UN TS
Figures 3 and 5, R
= 54 ,
= 54 ,
= 54 ,
= 54 ,
DIFF
t
400
1400
2000
ns
DPLH
DPHL
C
= C = 100pF
L2
L1
Driver Input to Output
Figures 3 and 5, R
DIFF
t
400
1400
1200
2000
C
= C = 100pF
L2
L1
Driver Output Skew
Figures 3 and 5, R
DIFF
t
250
ns
ns
DSKEW
t
- t
C
= C = 100pF
L1 L2
DPLH DPHL
Figures 3 and 5, R
DIFF
Driver Rise or Fall Time
t
, t
200
250
2200
DR DF
C
= C =100pF
L2
L1
Maximum Data Rate
f
kbps
ns
MꢂX
Driver Enable to Output High
Driver Enable to Output Low
Driver Disable Time from Low
Driver Disable Time from High
t
Figures 4 and 6, C = 100pF, S2 closed
3500
3500
300
DꢁH
L
t
t
Figures 4 and 6, C = 100pF, S1 closed
ns
DꢁL
DLꢁ
DHꢁ
L
Figures 4 and 6, C = 15pF, S1 closed
ns
L
t
Figures 4 and 6, C = 15pF, S2 closed
300
ns
L
t
t
,
RPLH
Receiver Input to Output
Figures 7 and 9; V
Figures 7 and 9; V
2.0V
2.0V
440
20
600
ns
ns
ID
ID
RPHL
Differential Receiver Skew
t
RSKEW
t
- t
RPLH RPHL
Receiver Enable to Output Low
Receiver Enable to Output High
Receiver Disable Time from Low
Receiver Disable Time from High
Time to Shutdown
t
Figures 2 and 8, C = 100pF, S1 closed
20
20
50
50
ns
ns
ns
ns
ns
RꢁL
L
t
Figures 2 and 8, C = 100pF, S2 closed
L
RꢁH
t
Figures 2 and 8, C = 100pF, S1 closed
200
200
200
500
500
700
RLꢁ
L
t
Figures 2 and 8, C = 100pF, S2 closed
L
RHꢁ
t
(Note 4)
50
SHDN
Driver Enable from Shutdown to
Output High
t
DꢁH
(SHDN)
Figures 4 and 6, C = 15pF, S2closed
0.2
0.2
0.2
0.2
1.3
1
1
1
1
ms
ms
L
Driver Enable from Shutdown to
Output Low
t
DꢁL
(SHDN)
Figures 4 and 6, C = 15pF, S1 closed
L
Receiver Enable from Shutdown
to Output High
t
RꢁH
(SHDN)
Figures 2 and 8, C = 100pF, S2 closed
ms
L
Receiver Enable from Shutdown
to Output Low
t
RꢁL
(SHDN)
Figures 2 and 8, C = 100pF, S1 closed
ms
L
Charge-Pump Oscillating
Frequency
f
MHz
OSC
NsatV1: ꢂll currents into the device are positive; all currents out of the device are negative. ꢂll voltages are referred to device
ground unless otherwise noted.
NsatV2: ∆V
and ∆V
are the changes in V
NsatV3: Current level applies to peak current just prior to foldback-current limiting.
and V , respectively, when the DI input changes state.
OD
OC
OD OC
NsatV4: The device is put into shutdown by bringing RE high and DE low. If the enable inputs are in this state for less than 50ns,
the device is guaranteed not to enter shutdown. If the enable inputs are in this state for at least 700ns, the device is guaran-
teed to have entered shutdown.
4
_______________________________________________________________________________________
High CMRR RS-485 Transceiver
with ±±60 ꢀsolation
Typical Operating Characteristics
(V = +5V, YR = ꢁR = ꢂR = ꢃR = ISOCOM, C1 = C2 = 0.047ꢄF, C3 = 1ꢄF, C4 = 10nF, T = +25°C, unless otherwise noted.)
CC
ꢂ
SHUTDOWN SUPPLY CURRENT
vs. TEMPERATURE
RECEIVER OUTPUT CURRENT
vs. RECEIVER OUTPUT LOW VOLTAGE
SUPPLY CURRENT vs. TEMPERATURE
160
300
200
100
45
40
35
30
25
20
15
10
5
V
= -50V
140
120
100
80
ISOCOM
R = 54Ω
L
0
-100
-200
-300
V
= 0V
ISOCOM
60
40
V
= +50V
ISOCOM
NO LOAD
20
0
0
-40 -30-20 -10 0 10 20 30 40 50 60 70 80 90
-40 -30-20 -10 0 10 20 30 40 50 60 70 80 90
0
1
2
3
4
5
6
TEMPERATURE (°C)
TEMPERATURE (°C)
OUTPUT LOW VOLTAGE (V)
RECEIVER OUTPUT CURRENT
vs. RECEIVER OUTPUT HIGH VOLTAGE
RECEIVER OUTPUT LOW VOLTAGE
vs. TEMPERATURE
RECEIVER OUTPUT HIGH VOLTAGE
vs. TEMPERATURE
20
18
16
14
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0
4.40
4.35
4.30
4.25
I
= -8mA
RO
I
= 8mA
RO
12
10
8
4.20
4.15
4.10
6
4.05
4.00
3.95
4
2
0
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
OUTPUT HIGH VOLTAGE (V)
-40 -20
0
20
40
60
80 100
-40 -20
0
20
40
60
80 100
TEMPERATURE (°C)
TEMPERATURE (°C)
DRIVER OUTPUT CURRENT
vs. DRIVER OUTPUT LOW VOLTAGE
DRIVER OUTPUT CURRENT
vs. DRIVER OUTPUT HIGH VOLTAGE
DRIVER OUTPUT CURRENT
vs. DIFFERENTIAL OUTPUT VOLTAGE
160
140
120
100
80
0
-10
-20
-30
-40
-50
100
10
1
-60
-70
-80
-90
60
40
0.1
-100
-110
-120
20
0
0.01
0
2
4
6
8
10
12
14
-8
-6
-4
-2
0
2
4
6
0
1
2
3
4
5
6
OUTPUT VOLTAGE (V)
OUTPUT HIGH VOLTAGE (V)
DIFFERENTIAL OUTPUT VOLTAGE (V)
_______________________________________________________________________________________
5
High CMRR RS-485 Transceiver
with ±±60 ꢀsolation
Typical Operating Characteristics (continued)
(V = +5V, YR = ꢁR = ꢂR = ꢃR = ISOCOM, C1 = C2 = 0.047ꢄF, C3 = 1ꢄF, C4 = 10nF, T = +25°C, unless otherwise noted.)
CC
ꢂ
DRIVER DIFFERENTIAL OUTPUT
VOLTAGE vs. TEMPERATURE
RECEIVER PROPAGATION DELAY
vs. TEMPERATURE
DRIVER PROPAGATION DELAY
vs. TEMPERATURE
1.98
1.96
1.94
1.92
1.90
1.88
1.86
1.84
1.82
1.80
490
480
470
460
1.52
1.50
1.48
1.46
1.44
1.42
1.40
1.38
1.36
R = 54Ω
L
R = 54Ω
L
450
440
430
420
410
1.34
1.32
-40
-20
0
20
40
60
80
-40
-20
0
20
40
60
80
-40
-20
0
20
40
60
80
TEMPERATURE (°C)
TEMPERATURE (°C)
TEMPERATURE (°C)
DRIVER ENABLE TIME
vs. TEMPERATURE
DRIVER DISABLE TIME
vs. TEMPERATURE
RECEIVER PROPAGATION DELAY
MAX3158 toc15
1.500
1.475
1.450
1.425
1.400
1.375
1.350
1.325
1.300
250
200
V
- V
B
A
0V
5V/div
150
100
50
0V
R
O
0
-40 -20
0
20
40
60
80 100
-40 -20
0
20
40
60
80 100
2µs/div
TEMPERATURE (°C)
TEMPERATURE (°C)
POWER-UP DELAY
(V = 0V)
POWER-UP DELAY
(V
= -50V)
DRIVER PROPAGATION DELAY
ISOCOM
ISOCOM
MAX3158 toc17
MAX3158 toc18
MAX3158 toc16
DE
5V/div
0V
DE
10V/div
DI
0V
2V/div
0V
VY
5V/div
-50V
VY
VY - VZ
10V/div
R
= 54Ω
DIFF
CL1 = CL2 = 100pF
100µs/div
2µs/div
40µs/div
±
_______________________________________________________________________________________
High CMRR RS-485 Transceiver
with ±±60 ꢀsolation
Typical Operating Characteristics (continued)
(V = +5V, YR = ꢁR = ꢂR = ꢃR = ISOCOM, C1 = C2 = 0.047ꢄF, C3 = 1ꢄF, C4 = 10nF, T = +25°C, unless otherwise noted.)
CC
ꢂ
POWER-UP DELAY
(V = +50V)
MAXIMUM COMMON-MODE VOLTAGE TO
GROUND vs. COMMON-MODE FREQUENCY
ISOCOM
MAX3158 toc19
70
60
50
40
30
20
10
0
MAXIMUM COMMON-MODE
VOLTAGE TO ISOCOM
DE
5V/div
0V
COMMON-MODE VOLTAGE TO
ISOCOM = 7V PEAK
+50V
VY
10V/div
100µs/div
0.1
1
10
COMMON-MODE FREQUENCY (kHz)
Test Circuits and Timing Diagrams
Y
3V
DE
C
L1
R
R
Y
Z
R
DIFF
DI
V
V
ID
OD
V
OC
C
L2
Z
Figure 1. Driver DC Test Load
Figure 3. Driver Timing Test Circuit
1kΩ
TEST POINT
RECEIVER
V
V
CC
CC
OUTPUT
S1
S2
S1
500Ω
C
L
OUTPUT
UNDER TEST
1kΩ
100pF
C
L
S2
Figure 4. Driver Enable/Disable Timing Test Load
Figure 2. Receiver Enable/Disable Timing Test Load
_______________________________________________________________________________________
7
High CMRR RS-485 Transceiver
with ±±60 ꢀsolation
Test Circuits and Timing Diagrams (continued)
3V
0V
3V
0V
DI
1.5V
1.5V
RE
1.5V
1.5V
t
t
DPHL
DPLH
1/2 V
O
t
t
, t
RLZ
RZL(SHDN) RZL
Z
V
RO
CC
0V
V
O
1.5V
V
V
+ 0.5V
- 0.5V
OUTPUT NORMALLY LOW
OUTPUT NORMALLY HIGH
OL
Y
1/2 V
O
V
= V (Y) - V (Z)
DIFF
V
O
0V
O
V
DIFF
90%
90%
RO
1.5V
OH
10%
10%
-V
t
DR
t
DF
t
, t
t
RHZ
RZH(SHDN) RZH
t
t
- t
DSKEW = | DPLH DPHL |
Figure 5. Driver Propagation Delays
Figure 8. Receiver Enable and Disable Times
3V
DE
1.5V
1.5V
0V
t
t
, t
DLZ
DZL(SHDN) DZL
Y, Z
B
RECEIVER
OUTPUT
2.3V
V
V
+ 0.5V
- 0.5V
OUTPUT NORMALLY LOW
OUTPUT NORMALLY HIGH
OL
V
R
ID
V
ATE
OL
A
Y, Z
0V
2.3V
OH
t
, t
t
DHZ
DZH(SHDN) DZH
Figure 6. Driver Enable and Disable Times
Figure 9. Receiver Propagation Delay Test Circuit
V
OH
RO
1.5V
1.5V
V
OUTPUT
OL
t
t
RPLH
RPHL
A
B
1V
-1V
INPUT
t
t
- t
RSKEW = | RPLH RPHL |
Figure 7. Receiver Propagation Delays
8
_______________________________________________________________________________________
High CMRR RS-485 Transceiver
with ±±60 ꢀsolation
Pin Description
P N
NAME
FUNCT ON
SSOP
Pꢀ P
Receiver Output. When RE is low and ꢂ - ꢃ > -50mV, RO will be high; if ꢂ - ꢃ ≤ -200mV,
RO will be low.
1
2
RO
2
3
3
4
RE
Receiver Output Enable. Drive RE low to enable RO.
DE
Driver Output Enable. Drive DE high to enable driver outputs.
Driver Input. With DE high, a low on DI forces the noninverting output low and the inverting
output high; with DI high, outputs reverse.
4
5
5
6
DI
C1LO
Connect to the negative terminal of C1 (0.047ꢄF, 100V).
6, 7,
12, 22,
23
1, 12,
14, 15,
28
N.C.
No Connection. Not internally connected.
8
9
7
8
C1HI
Connect to the positive terminal of C1 (0.047ꢄF, 100V).
Internally generated power-supply voltage, referenced to the cable ground (ISOCOM).
Connect a 1ꢄF capacitor to ISOCOM.
ISOVCC
Half/Full-Duplex Selector Pin. Leave open, or connect to ISOCOM to select Full Duplex,
or connect to ISOVCC to select Half Duplex.
10
11
13
9
H/F
ꢁR
YR
Connect to ISOCOM for a 1.5kΩ input impedance on ꢁ. Leave open for a 12kΩ input
impedance on ꢁ.
10
11
Connect to ISOCOM for a 1.5kΩ input impedance on Y. Leave open for a 12kΩ input
impedance on Y.
14
15
16
17
18
13
16
17
18
19
ISOCOM
Cable Ground
ꢁ
Y
ꢃ
ꢂ
Inverting Driver Output (and Inverting Receiver Input in Half-Duplex Mode)
Noninverting Driver Output (and Noninverting Receiver Input in Half-Duplex Mode)
Inverting Receiver Input in Full-Duplex Mode
Noninverting Receiver Input in Full-Duplex Mode
Connect to ISOCOM for a 1.5kΩ input impedance on ꢃ. Leave open for a 12kΩ input
impedance on ꢃ.
19
20
20
21
ꢃR
ꢂR
Connect to ISOCOM for a 1.5kΩ input impedance on ꢂ. Leave open for a 12kΩ input
impedance on ꢂ.
21
24
25
22
23
24
C2HI
C2LO
GND
Connect to the positive terminal of C2 (0.047ꢄF, 100V).
Connect to the negative terminal of C2 (0.047ꢄF, 100V).
Ground
Transmitter Phase. Leave open, or connect to GND for normal transmitter polarity, or connect
26
25
TXP
RXP
to V
to invert the transmitter polarity.
CC
Receiver Phase. Leave open, or connect to GND for normal receiver polarity, or connect to
to invert the receiver polarity.
27
28
26
27
V
CC
V
+4.75V to +5.25V Positive Supply. Connect a 0.1ꢄF capacitor to GND.
CC
_______________________________________________________________________________________
9
High CMRR RS-485 Transceiver
with ±±60 ꢀsolation
connect it to V . To invert the receiver phase, drive
CC
Detailed Description
RXP high or connect it to V . Note that the receiver
CC
The MꢂX3158 is a high CMRR RS-485/RS-422 data-
communications interface providing 60V isolation in a
hybrid microcircuit. ꢂ single +5V supply on the logic
side powers both sides of the interface, with external
100V capacitors transferring power from the logic side
to the isolated side (see Block Diagram). The MꢂX3158
typically draws 25mꢂ of supply current when unloaded
or when fully loaded with the driver disabled. Supply
current drops to 25ꢄꢂ when the device is placed in
shutdown mode (see Low-Power Shutdown Mode sec-
tion). The MꢂX3158 transceiver for RS-485/RS-422
communication contains one driver and one receiver.
threshold is positive when RXP is high.
The MꢂX3158 can operate in full- or half-duplex mode.
Connect H/F to ISOCOM for full-duplex mode, and con-
nect it to ISOVCC for half-duplex operation. In half-
duplex mode, the receiver inputs are switched to the
driver outputs, connecting outputs Y and ꢁ to inputs ꢂ
and ꢃ, respectively. In half-duplex mode, the internal
full-duplex receiver input resistors are still connected to
pins ꢂ and ꢃ.
Low-Power Shutdown Mode
The low-power shutdown mode is initiated by bringing
both RE high and DE low. In shutdown, this device typi-
cally draws only 25ꢄꢂ of supply current, and no power
is transferred across the isolation capacitors in this
mode. RE and DE may be driven simultaneously; the
parts are guaranteed not to enter shutdown if RE is
high and DE is low for less than 50ns. If the inputs are
in this state for at least 700ns, the parts are guaranteed
This device features fail-safe circuitry, which guaran-
tees a logic-high receiver output when the receiver
inputs are open or shorted, or when they are connected
to a terminated transmission line with all drivers dis-
abled (see Fail-Safe section). The MꢂX3158 is selec-
table between half- and full-duplex communication by
connecting a selector pin to ISOVCC or ISOCOM,
respectively. Drivers are output short-circuit current lim-
ited. Thermal shutdown circuitry protects drivers
against excessive power dissipation. When activated,
the thermal shutdown circuitry places the driver outputs
into a high-impedance state. The device also features
independently programmable receiver and transmitter
output phase through separate pins. The MꢂX3158 is a
low-cost replacement for opto-isolated transceivers.
to enter shutdown. Enable times t_
and t_ in the
ꢁL
ꢁH
Switching Characteristics table assume the part was
not in a low-power shutdown state. Enable times
t_ꢁH
and t_
assume the parts were shut
(SHDN)
(SHDN)
ꢁL
down. It takes drivers and receivers longer to become
enabled from low-power shutdown mode t_
,
ꢁH(SHDN)
t_
than from driver/receiver-disable mode
ꢁL(SHDN)
(t_ , t_ ).
ꢁH
ꢁL
Fail-Safe
The MꢂX3158 gulꢂlꢁattI a logic-high receiver output
when the receiver inputs are shorted or open, or when
they are connected to a terminated transmission line with
all drivers disabled. The receiver threshold is fixed
between -50mV and -200mV. If the differential receiver
input voltage (ꢂ - ꢃ) is greater than or equal to -50mV,
RO is logic high. If ꢂ - ꢃ is less than or equal to -200mV,
RO is logic low. In the case of a terminated bus with all
transmitters disabled, the receiver’s differential input volt-
age is pulled to 0V by the termination. With the receiver
thresholds of the MꢂX3158, this results in a logic high
with a 50mV minimum noise margin. Unlike competitor’s
fail-safe devices, the -50mV to -200mV threshold com-
plies with the 200mV EIꢂ/TIꢂ-485 standard.
Driver Output Protection
Two mechanisms prevent excessive output current and
power dissipation caused by faults or by bus con-
tention. The first, a foldback current limit on the output
stage, provides immediate protection against short cir-
cuits over the whole common-mode voltage range (see
Typical Operating Characteristics). The second, a ther-
mal shutdown circuit, forces the driver outputs into a
high-impedance state if the die temperature becomes
excessive—typically around +150°C.
Applications ꢀnformation
Capacitor and Grounding Resistor
Selection
The value for the charge-pump capacitors C1 and C2
should be between 47nF and 100nF. Smaller values will
result in insufficient supply voltage on the isolated side.
Larger values are allowed but will not result in better
charge-pump capacity. The values for C1 and C2, as
well as that of C4, determine the maximum frequency
and amplitude of the voltage difference (under operat-
ing conditions) between the local and isolated ground.
ꢃesides the capacitor values, this maximum frequency
MAX3158 Programming
The MꢂX3158 has several programmable operating
modes. Occasionally, twisted-pair lines are reversed.
The MꢂX3158 has two pins that invert the phase of the
driver and the receiver to correct for this problem. For
normal operation, drive TXP and RXP low, connect
them to ground, or leave them unconnected (internal
pulldown). To invert the driver phase, drive TXP high or
16 ______________________________________________________________________________________
High CMRR RS-485 Transceiver
with ±±60 ꢀsolation
Block Diagram
Y
Z
DI
TXP
YR
ZR
DE
RO
A
B
RE
RXP
AR
BR
MAX3158
H/F
V
CC
ISOVCC
POWER
OSC
GND
C1L C2L
C1H C2H
ISOCOM
and amplitude are also determined by the resistance
between the remote ground and the ISOCOM pin. The
receiver input resistors will cause the isolated common
voltage to go to the mean voltage of the receiver inputs,
which will be a direct function of the remote ground
potential. The receiver input resistance and the capaci-
tors C1, C2, and C4 set up a time constant that limits
how fast the ISOCOM pin can follow variations in the
remote ground voltage. Connecting YR and ꢁR in half-
duplex operation, or ꢂR and ꢃR in full-duplex operation,
to ISOCOM results in a relatively low input impedance of
the MꢂX3158 receiver inputs (2kΩ). This allows for a
60Hz sine wave with a 60V maximum amplitude (see
Typical Operating Characteristics). If YR, ꢁR, ꢂR, and
ꢃR are left open, the receiver input impedance is 12kΩ
allowing up to 32 transceivers on the bus. To guarantee
the same low time constant under those conditions, use
a shielded cable with a 1kΩ resistor connected between
the shield and ISOCOM. Using a lower value for this
resistor is not recommended because this could trigger
a holding current in the internal ESD protection device if
the 75V isolation limit is exceeded.
ꢂ single point hard-ground connection for the shield is
recommended.
Communication Between
Two MAX3158s
If two MꢂX3158 devices are used to communicate with
each other, one of the devices must have ISOCOM
connected to local ground. Failure to do so will result in
floating ISOCOM pins, with both devices trying to adapt
to the isolated ground of the other.
Chip ꢀnformation
TRꢂNSISTOR COUNT: 1309
______________________________________________________________________________________ 11
High CMRR RS-485 Transceiver
with ±±60 ꢀsolation
Pin Configurations
TOP VIEW
RO
RE
1
2
3
4
5
6
7
8
9
28 V
CC
N.C.
RO
1
2
28 N.C.
27 RXP
26 TXP
25 GND
24 C2LO
23 N.C.
22 N.C.
21 C2HI
20 AR
V
27
CC
DE
RE
3
26 RXP
25 TXP
DI
DE
4
C1LO
N.C.
N.C.
C1HI
ISOVCC
GND
DI
5
24
MAX3158
MAX3158
C1LO
C1HI
ISOVCC
H/F
6
23 C2LO
C2HI
AR
BR
A
7
22
21
20
19
18
17
16
15
8
9
H/F 10
ZR 11
19 BR
10
11
12
13
14
ZR
18
17
16
15
A
B
Y
Z
B
YR
N.C.
N.C. 12
Y
YR 13
Z
ISOCOM
N.C.
ISOCOM 14
N.C.
28VSSOP
28VPꢀ P
12 ______________________________________________________________________________________
High CMRR RS-485 Transceiver
with ±±60 ꢀsolation
Package ꢀnformation
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.mlxim-iꢃ.ꢃsm/plꢃklgtI.)
2
1
INCHES
MILLIMETERS
MAX
MAX
1.99
0.21
0.38
0.20
DIM
A
MIN
0.068
MIN
1.73
0.05
0.25
0.09
INCHES
MAX
MILLIMETERS
MAX
6.33
6.33
7.33
MIN
MIN
6.07
6.07
7.07
8.07
N
0.078
14L
16L
20L
D
D
D
D
D
A1
B
0.239 0.249
0.239 0.249
0.278 0.289
0.317 0.328
0.002 0.008
0.010 0.015
0.004 0.008
C
8.33 24L
E
H
SEE VARIATIONS
0.205 0.212 5.20
0.0256 BSC
D
0.397 0.407 10.07 10.33
28L
E
5.38
e
0.65 BSC
H
0.301 0.311 7.65
0.025 0.037 0.63
7.90
0.95
8∞
L
0∞
8∞
0∞
N
A
C
B
L
e
A1
D
NOTES:
1. D&E DO NOT INCLUDE MOLD FLASH.
2. MOLD FLASH OR PROTRUSIONS NOT TO EXCEED .15 MM (.006").
3. CONTROLLING DIMENSION: MILLIMETERS.
4. MEETS JEDEC MO150.
PROPRIETARY INFORMATION
TITLE:
PACKAGE OUTLINE, SSOP, 5.3 MM
APPROVAL
DOCUMENT CONTROL NO.
REV.
5. LEADS TO BE COPLANAR WITHIN 0.10 MM.
1
21-0056
C
1
______________________________________________________________________________________ 13
High CMRR RS-485 Transceiver
with ±±60 ꢀsolation
Package ꢀnformation (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.mlxim-iꢃ.ꢃsm/plꢃklgtI.)
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 ꢀntegrated Products, 126 San Gabriel Drive, Sunnyvale, CA 9468± 468-737-7±66
© 2003 Maxim Integrated Products
Printed USꢂ
is a registered trademark of Maxim Integrated Products.
相关型号：
MAX3160E
+5kV ESD-Protected, +3.0V to +5.5V, 10nA, RS-232/RS-485/RS-422 Multiprotocol Transceivers
MAXIM
MAX3160ECAP
+5kV ESD-Protected, +3.0V to +5.5V, 10nA, RS-232/RS-485/RS-422 Multiprotocol Transceivers
MAXIM
MAX3160ECAP+T
Line Transceiver, 1 Func, 1 Driver, 1 Rcvr, CMOS, PDSO20, 5.30 MM, MO-150, SSOP-20
MAXIM
MAX3160ECAP-T
Line Transceiver, 1 Func, 1 Driver, 1 Rcvr, CMOS, PDSO20, 5.30 MM, MO-150, SSOP-20
MAXIM
©2020 ICPDF网 联系我们和版权申明