LTC2876/LTC2877
±60V Rugged PROFIBUS
RS485 Transceivers
FeaTures
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DescripTion
The
LTC
®
2876
and LTC2877 are PROFIBUS RS485
transceivers designed to meet the test specifications for
PROFIBUS-DP masters and PROFIBUS-DP slaves, fully
compatible with IEC 61158-2, type 3: medium attachment
unit (MAU). With operation up to 20Mbps, the LTC2876/
LTC2877 supports all PROFIBUS data rates up to 12Mbps.
The LTC2876 and LTC2877 are exceptionally robust, toler-
ating ±60V faults on the bus pins and protected to ±52kV
ESD. These devices are suitable for harsh environments
or where 24V power might be inadvertently connected.
Extended ±25V input common mode range and full fail-
safe operation improve data communication reliability in
noisy systems.
The LTC2876 and LTC2877 meet PROFIBUS and RS485
specifications with a supply voltage of 4.5V to 5.5V but
can operate down to 3V with reduced supply current.
Product Selection Guide
PART NUMBER
LTC2876
LTC2877
LOGIC SUPPLY PIN
NO
YES
PACKAGE
DFN-8, MSOP-8
DFN-10, MSOP-10
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PROFIBUS IEC 61158-2 Compliant
Protected from Overvoltage Line Faults to ±60V
±52kV ESD Interface Pins, ±15kV All Other Pins
±2kV (Level 4) IEC61000-4-4 Fast Transient Burst
±25V Working Common Mode Range
20Mbps Maximum Baud Rate
1.65V to 5.5V Logic Supply Pin for Flexible Digital
Interfacing (LTC2877)
5V Supply Can Operate Down to 3V for Low Power,
Low Swing Applications
Fully Balanced Differential Receiver Thresholds with
240mV Hysteresis for Superior Noise Tolerance and
Low Duty Cycle Distortion
Receiver Failsafe for Open, Shorted and Terminated
Conditions
Wide Operating Temperature Range: –40°C to 125°C
Available in Small DFN and MSOP Packages
applicaTions
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PROFIBUS-DP
Industrial Communication Networks
RS485 and RS422 Systems
3V Low Voltage Differential Signaling
L,
LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
Typical applicaTion
1.8V
5V
5V
1µF
390
PB
µC
SENSOR
RE
DI
DE
GND
PA
PA
390
Z
O
= 150Ω
PB
220
390
B´
220
A´
390
B´– A´
2V/DIV
0.1µF
V
L
RO
LTC2877
V
CC
Eye Diagram of 12Mbps Signal at
the Near and Far End of a 100m
PROFIBUS Cable Driven by the
LTC2877 Using 2
8
–1 PRBS Pattern
PB–PA
2V/DIV
PROFIBUS
CABLE
NEAR END
FAR END
28767 TA01a
20ns/DIV
28767 TA01b
28767fa
For more information
www.linear.com/LTC2876
1
LTC2876/LTC2877
absoluTe MaxiMuM raTings
(Notes 1, 2)
Supply Voltages (V
CC
, V
L
) ............................ –0.3V to 6V
Logic Input Voltages (RE, DE, DI) ................ –0.3V to 6V
Line Interface I/O (PA, PB) .......................... –60V to 60V
Line Interface I/O Difference (PB–PA) ..... –120V to 120V
Receiver Output (RO)
LTC2876 ......................................–0.3V to V
CC
+ 0.3V
LTC2877 ....................................... –0.3V to V
L
+ 0.3V
Operating Ambient Temperature Range (Note 3)
LTC287xC ................................................ 0°C to 70°C
LTC287xI..............................................–40°C to 85°C
LTC287xH .......................................... –40°C to 125°C
Storage Temperature Range .................. –65°C to 150°C
Lead Temperature (Soldering, 10sec).................... 300°C
pin conFiguraTion
LTC2876
TOP VIEW
RO
RE
DE
DI
1
2
3
4
9
GND
8 V
CC
7 PA
6 PB
5 GND
LTC2876
TOP VIEW
RO
RE
DE
DI
1
2
3
4
9
GND
8
7
6
5
V
CC
PA
PB
GND
MS8E PACKAGE
8-LEAD PLASTIC MSOP
T
JMAX
= 150°C,
θ
JA
= 40°C/W,
θ
JC
= 10°C/W
EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB
DD PACKAGE
8-LEAD (3mm
×
3mm) PLASTIC DFN
T
JMAX
= 150°C,
θ
JA
= 43°C/W,
θ
JC
= 5.5°C/W
EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB
LTC2877
TOP VIEW
RO
RE
DE
DI
V
L
1
2
3
4
5
11
GND
10 V
CC
9 PA
8 PB
7 NC
6 GND
LTC2877
TOP VIEW
RO
RE
DE
DI
V
L
1
2
3
4
5
11
GND
10
9
8
7
6
V
CC
PA
PB
NC
GND
DD PACKAGE
10-LEAD (3mm
×
3mm) PLASTIC DFN
T
JMAX
= 150°C,
θ
JA
= 43°C/W,
θ
JC
= 5.5°C/W
EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB
MSE PACKAGE
10-LEAD PLASTIC MSOP
T
JMAX
= 150°C,
θ
JA
= 40°C/W,
θ
JC
= 10°C/W
EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB
2
28767fa
For more information
www.linear.com/LTC2876
LTC2876/LTC2877
orDer inForMaTion
Lead Free Finish
TUBE
LTC2876CMS8E#PBF
LTC2876IMS8E#PBF
LTC2876HMS8E#PBF
LTC2876CDD#PBF
LTC2876IDD#PBF
LTC2876HDD#PBF
LTC2877CMSE#PBF
LTC2877IMSE#PBF
LTC2877HMSE#PBF
LTC2877CDD#PBF
LTC2877IDD#PBF
LTC2877HDD#PBF
TAPE AND REEL
LTC2876CMS8E#TRPBF
LTC2876IMS8E#TRPBF
LTC2876HMS8E#TRPBF
LTC2876CDD#TRPBF
LTC2876IDD#TRPBF
LTC2876HDD#TRPBF
LTC2877CMSE#TRPBF
LTC2877IMSE#TRPBF
LTC2877HMSE#TRPBF
LTC2877CDD#TRPBF
LTC2877IDD#TRPBF
LTC2877HDD#TRPBF
PART MARKING
LTGTN
LTGTN
LTGTN
LGTM
LGTM
LGTM
LTGTQ
LTGTQ
LTGTQ
LGTP
LGTP
LGTP
PACKAGE DESCRIPTION
8-Lead Plastic MSOP
8-Lead Plastic MSOP
8-Lead Plastic MSOP
8-Lead Plastic DFN
8-Lead Plastic DFN
8-Lead Plastic DFN
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead Plastic DFN
10-Lead Plastic DFN
10-Lead Plastic DFN
TEMPERATURE RANGE
0°C to 70°C
–40°C to 85°C
–40°C to 125°C
0°C to 70°C
–40°C to 85°C
–40°C to 125°C
0°C to 70°C
–40°C to 85°C
–40°C to 125°C
0°C to 70°C
–40°C to 85°C
–40°C to 125°C
http://www.linear.com/product/LTC2876#orderinfo
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on nonstandard lead based finish parts.
For more information on lead free part marking, go to:
http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to:
http://www.linear.com/tapeandreel/.
Some packages are available in 500 unit reels through
designated sales channels with #TRMPBF suffix.
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= V
L
= 5V unless otherwise noted.
SYMBOL
Supplies
V
CC
V
L
I
CCS
Primary Power Supply
Logic Interface Power Supply
LTC2876 Supply Current in Shutdown
Mode
LTC2877 Supply Current in Shutdown
Mode
I
CCR
I
CCD
I
CCDR
Supply Current with Only Receiver
Enabled
Supply Current with Only Driver
Enabled
Supply Current with Both Driver and
Receiver Enabled
LTC2877 Logic Supply Current in
Shutdown Mode
LTC2877 Logic Supply Current with
Both Driver and Receiver Enabled
PROFIBUS, RS485
Low Voltage RS485 (Note 6)
LTC2877 Only
DE = 0V,
RE
= V
CC
, DI = V
CC
DE = 0V,
RE
= V
CC
, DI = 0V
DE = 0V,
RE
= V
L
= V
CC
, DI = 0V or V
L
No Load, DE = 0V,
RE
= 0V
No Load, DE =
RE
= V
CC
= V
L
No Load, DE = V
CC
= V
L
,
RE
= 0V
DE = 0V,
RE
= V
L
, DI = V
L
DE = 0V,
RE
= V
L
, DI = 0V
DE = V
L
,
RE
= 0V, DI = V
L
DE = V
L
,
RE
= 0V, DI = 0V
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elecTrical characTerisTics
PARAMETER
CONDITIONS
MIN
4.5
3.0
1.65
TYP
MAX
5.5
V
CC
UNITS
V
V
V
µA
µA
µA
µA
µA
µA
µA
µA
µA
µA
0
12
0
600
700
750
0
12
30
65
5
25
5
900
1100
1200
5
25
60
120
28767fa
For more information
www.linear.com/LTC2876
3
LTC2876/LTC2877
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= V
L
= 5V unless otherwise noted.
SYMBOL
Driver
V
OD(PP)
Differential Bus Output Voltage (B´–A´) PROFIBUS LOAD (Figure 1)
with PROFIBUS Load
R
CABLE
= 0Ω, V
CC
= 4.5V to 5.5V
R
CABLE
= 5.5Ω, V
CC
= 4.5V to 5.5V
R
CABLE
= 11Ω, V
CC
= 4.75V to 5.5V
Single-Ended Bus Output Amplitude
Difference (B´
PP
– A´
PP
)
Single-Ended Bus Output Amplitude
Sum |B´
PP
+ A´
PP
|
RS485 Differential Driver Output
Voltage, in Either Logic State
RS422 Differential Driver Output
Voltage, Either Logic State
All of the Conditions Above
All of the Conditions Above
Figure 2 with No Load
R
L
= 27Ω,V
CC
= 4.5V to 5.5V (Figure 2)
R
L
= 27Ω,V
CC
= 3.0V to 3.6V (Figure 2)
|V
OD(422)
|
Figure 2 with No Load
R
L
= 50Ω,V
CC
= 4.5V to 5.5V (Figure 2)
R
L
= 50Ω,V
CC
= 3.0V to 3.6V (Figure 2)
Δ|V
OD(485)
|, RS485, RS422 Change in Magnitude of R
L
= 27Ω (RS485) or
Δ|V
OD(422)
| Driver Differential Output Voltage
R
L
= 50Ω (RS422) (Figure 2)
V
OC(485)
,
V
OC(422)
RS485, RS422 Driver Common-Mode
Output Voltage
R
L
= 27Ω (RS485) or
R
L
= 50Ω (RS422) (Figure 2)
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elecTrical characTerisTics
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
4
4
4
7
7
7
0.5
V
P-P(DIFF)
V
P-P(DIFF)
V
P-P(DIFF)
V
V
V
BPP-APP
V
BPP+APP
|V
OD(485)
|
4
V
CC
1.5
0.8
2
1
3.4
1.8
V
CC
4
2
0.2
3
0.2
±150
±250
160
112
135
±25
50
–50
120
–120
240
200
–200
V
V
V
V
V
V
V
V
V
mA
µA
µA
kΩ
V
mV
mV
mV
Δ|V
OC(485)
|, RS485, RS422 Change in Magnitude of R
L
= 27Ω (RS485) or
Δ|V
OC(422)
| Driver Common-Mode Output Voltage R
L
= 50Ω (RS422) (Figure 2)
I
OSD
Receiver
I
IN
R
IN
V
CM
V
TS
+
V
TS
–
ΔV
TS
V
TFS
+
V
TFS
–
ΔV
TFS
V
OH
V
OL
Input Current (PA, PB)
Input Resistance
Common Mode Input Voltage
(PA+PB)/2 for Data Reception
Differential Input Signal Threshold
Voltage (PB–PA) Rising
Differential Input Signal Threshold
Voltage (PB–PA) Falling
Differential Input Signal Hysteresis
Differential Input Failsafe Threshold
Voltage (PB–PA) Rising
Differential Input Failsafe Threshold
Voltage (PB–PA) Falling
Differential Input Failsafe Hysteresis
Receiver Output High Voltage
–25V ≤ V
CM
≤ 25V, Edge Rates > 100mV/µs
(Note 5) (Figure 13)
–25V ≤ V
CM
≤ 25V, Edge Rates > 100mV/µs
(Note 5) (Figure 13)
Edge Rates > 100mV/µs (Note 5) (Figure 13)
–25V ≤ V
CM
≤ 25V, DC Bus Voltages
(Figure 13)
–25V ≤ V
CM
≤ 25V, DC Bus Voltages
(Figure 13)
DC Bus Voltages (Figure 13)
V
CC
≥ 4.5V, I(RO) = –3mA (LTC2876)
V
L
≥ 2.25V, I(RO) = –3mA (LTC2877)
V
L
< 2.25V, I(RO) = –2mA (LTC2877)
V
L
≥ 1.65V, I(RO) = 3mA (LTC2877)
V
CC
≥ 3.0V, I(RO) = 3mA (LTC2876)
V
CC
= 0V or 5V, V
BUS
= 12V (Figure 4)
V
CC
= 0V or 5V, V
BUS
= –7V (Figure 4)
V
BUS
= –25V or 25V (Figure 4)
Maximum Driver Short-Circuit Current
–60V ≤ (PB or PA) ≤ 60V (Figure 3)
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l
l
l
–100
75
l
l
–20
–50
–75
–120
45
–200
–200
mV
mV
mV
V
V
V
l
l
l
l
l
l
l
V
CC
– 0.4V
V
L
– 0.4V
V
L
– 0.4V
0.4
0.4
–20
0
–40
5
Receiver Output Low Voltage
V
V
µA
µA
Receiver Three-State (High Impedance)
RE
= High, RO = 0V
Output Current on RO
Receiver Three-State (High Impedance)
RE
= High, RO = V
CC
(LTC2876) or V
L
(LTC2877)
Output Current on RO
4
28767fa
For more information
www.linear.com/LTC2876
LTC2876/LTC2877
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= V
L
= 5V unless otherwise noted.
SYMBOL
PARAMETER
Receiver Short-Circuit Current
Logic
Low Level Input Voltage (DE, DI,
RE)
High Level Input Voltage (DE, DI,
RE)
Logic Input Current Low (DE)
Logic Input Current Low (DI,
RE)
Logic Input Current High (DE)
Logic Input Current High (DI,
RE)
ESD (Note 4)
ESD Protection Level of Interface Pins
(PA, PB)
ESD Protection Level of All Other Pins
(DE, DI,
RE,
V
CC
, V
L
)
Human Body Model to GND or V
CC
, or V
L
,
Powered or Unpowered
Human Body Model to GND, Unpowered
Human Body Model
±26
±52
±15
kV
kV
kV
LTC2876, 3.0 ≤ V
CC
≤ 5.5V
LTC2877, 1.65 ≤ V
L
≤ 5.5V
LTC2876, 3.0 ≤ V
CC
≤ 5.5V
LTC2877, 1.65 ≤ V
L
≤ 5.5V
DE = 0V
DI or
RE
= 0V
DE = V
CC
(LTC2876) or V
L
(LTC2877)
(DI,
RE)
= V
CC
(LTC2876) or V
L
(LTC2877)
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l
l
l
elecTrical characTerisTics
CONDITIONS
RE
= Low, RO = 0V or V
CC
(LTC2876) or V
L
(LTC2877)
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MIN
TYP
±12
MAX
±20
UNITS
mA
0.25 •
V
CC
0.25 •
V
L
0.75 •
V
CC
0.75 •
V
L
0
–3
3
–10
10
0
–5
–20
20
5
V
V
V
V
µA
µA
µA
µA
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= V
L
= 5V unless otherwise noted.
SYMBOL
f
MAX
Driver
t
PLHD
, t
PHLD
Δt
PD
t
SKEWD
t
RD
, t
FD
t
ZLD
, t
ZHD
,
t
LZD
, t
HZD
t
ZHSD
, t
ZLSD
t
SHDND
Receiver
t
PLHR
, t
PHLR
Δt
PR
t
RR
, t
FR
t
ZLR
, t
ZHR
,
t
LZR
, t
HZR
t
ZHSR
, t
ZLSR
t
SHDNR
Receiver Input to Output
Receiver Input to Output Difference
|t
PLHR
– t
PHLR
|
Receiver Output Rise or Fall Time
Receiver Enable/Disable Time
Receiver Enable from Shutdown
Time to Shutdown with
RE
V
CM
= 2.25V, (PB–PA) = ±1.5V,
t
R
and t
F
< 4ns, V
CC
= 3.3V or 5V (Figure 7)
(Figure 7)
(Figure 7)
DE = High (Figure 8)
DE = 0V, (Figure 9)
DE = 0V, (Figure 9)
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l
l
l
l
l
swiTching characTerisTics
PARAMETER
Maximum Data Rate
Driver Input to Output
Driver Input to Output Difference
|t
PLHD
– t
PHLD
|
Driver Output PB to Output PA
Driver Rise or Fall Time
Driver Enable or Disable Time
Driver Enable from Shutdown
Time to Shutdown with DE
CONDITIONS
(Note 4)
V
CC
= 3.3V or 5V (Figure 5)
(Figure 5)
(Figure 5)
V
CC
= 3.3V or 5V (Figure 5)
RE
= 0V (Figure 6)
RE
= High (Figure 6)
RE
= High (Figure 6)
l
MIN
20
TYP
MAX
UNITS
Mbps
l
l
l
l
l
l
l
13
2
50
9
±9
ns
ns
ns
ns
ns
µs
ns
ns
ns
ns
ns
µs
ns
4
15
180
15
180
50
2
3
70
14
15
40
9
40
28767fa
For more information
www.linear.com/LTC2876
5
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