19-5017; Rev 1; 4/10
High-ESD Profibus RS-485 Transceiver
General Description
The MAX14770E is a half-duplex,
Q35kV
high ESD-
protected transceiver for PROFIBUS-DP and RS-485
applications. In addition, it can be used for RS-422/V.11
communications. The MAX14770E is designed to meet
IEC 61158-2, TIA/EIA-422-B, TIA/EIA-485-A, V.11, and
X.27 standards.
The MAX14770E operates from a +5V supply and has
true fail-safe circuitry that guarantees a logic-high receiv-
er output when the receiver inputs are open or shorted.
The MAX14770E features a 1/4 standard-unit load
receiver input impedance, allowing up to 128 1/4 unit
load transceivers on the bus. Drivers are short-circuit
current limited and are protected against excessive
power dissipation by thermal-shutdown circuitry.
The MAX14770E is available in 8-pin SO and tiny TDFN
(3mm x 3mm) packages, and is specified over the extend-
ed (-40NC to +85NC) and automotive (-40NC to +125NC)
temperature ranges.
S
+4.5V to +5.5V Supply Voltage
S
20Mbps Data Rate
S
Short-Circuit Protected
S
True Fail-Safe Receiver
S
Thermal-Shutdown Protected
S
Hot Swappable
S
High ESD Protection
±35kV Human Body Model (HBM)
±20kV IEC 61000-4-2 Air Gap
±10kV IEC 61000-4-2 Contact
S
-40NC to +125NC Automotive Temperature Range
in Tiny 8-Pin (3mm x 3mm) TDFN
Features
S
Meets EIA 61158-2 Type 3 PROFIBUS-DP
MAX14770E
Ordering Information
PART
MAX14770EESA+T
MAX14770EATA+T
TEMP RANGE
PIN-
PACKAGE
TOP
MARK
—
BMG
Applications
PROFIBUS-DP Networks
Industrial Fieldbuses
Motion Controllers
RS-485 Networks
Machine Encoders
-40NC to +85NC 8 SO
-40NC to +125NC 8 TDFN-EP*
+Denotes
a lead(Pb)-free/RoHS-compliant package.
T = Tape and reel.
*EP
= Exposed pad.
Functional Diagram
RO
RE
R
A
SHUTDOWN
Typical PROFIBUS-DP Operating Circuit appears at end of
data sheet.
DE
DI
B
D
MAX14770E
The PROFI BUS PROCESS FIELD BUS logo is a registered
trademark of PROFIBUS and PROFINET International (PI).
_______________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
High-ESD Profibus RS-485 Transceiver
MAX14770E
ABSOLUTE MAXIMUM RATINGS
(Voltages referenced to GND.)
V
CC
.......................................................................-0.3V to +6.0V
RE,
RO.......................................................-0.3V to (V
CC
+ 0.3V)
DE, DI ...................................................................-0.3V to +6.0V
A, B.....................................................................-8.0V to +13.0V
Short-Circuit Duration (RO, A, B) to GND .................Continuous
Continuous Power Dissipation (T
A
= +70NC)
8-Pin SOIC (derate 7.6mW/NC above +70NC) ............606mW
8-Pin TDFN (derate 24.4mW/NC above +70NC) ........1951mW
Junction-to-Ambient Thermal Resistance (B
JA
) (Note 1)
8-Pin SO ....................................................................132NC/W
8-Pin TDFN..................................................................41NC/W
Junction-to-Case Thermal Resistance (B
JC
) (Note 1)
8-Pin SO ......................................................................38NC/W
8-Pin TDFN....................................................................8NC/W
Operating Temperature Range
8-Pin SO ......................................................... -40NC to +85NC
8-Pin TDFN................................................... -40NC to +125NC
Storage Temperature Range............................ -65NC to +150NC
Junction Temperature Range........................... -40NC to +150NC
Lead Temperature (soldering, 10s) ................................+300NC
Soldering Temperature (reflow) ........................................ 260NC
Note 1:
Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-
layer board. For detailed information on package thermal considerations, refer to
www.maxim-ic/thermal-tutorial.
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.
ELECTRICAL CHARACTERISTICS
(V
CC
= +5V
Q10%,
T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V
CC
= +5V, T
A
= +25NC.) (Note 2)
PARAMETER
Power-Supply Range
Supply Current
Shutdown Supply
Current
DRIVER
Differential Driver
Output
Differential Driver
Peak-to-Peak Output
Change in Magnitude
of Differential Output
Voltage
Driver Common-
Mode Output Voltage
Change in Common-
Mode Voltage
Driver Short-Circuit
Output Current
(Note 5)
Driver Short-Circuit
Foldback Output
Current (Note 5)
|V
OD
|
V
ODPP
R
L
= 54I, DI = V
CC
or GND; Figure 1
Figure 2 (Note 3)
2.1
4.0
6.8
V
V
SYMBOL
V
CC
I
CC
DE = 1,
RE
= 0 or
DE = 0,
RE
= 0 or
DE = 1,
RE
= 1; no load
DE = 0,
RE
= 1
CONDITIONS
MIN
4.5
2.5
TYP
MAX
5.5
4
UNITS
V
mA
I
SH
15
FA
DV
OD
R
L
= 54I; Figure 1 (Note 4)
-0.2
0
+0.2
V
V
OC
DV
OC
R
L
= 54I; Figure 1
R
L
= 54I; Figure 1 (Note 4)
0V
P
V
OUT
P
+12V; output low
-7V
P
V
OUT
P
V
CC
; output high
(V
CC
- 1V)
P
V
OUT
P
+12V; output low
-7V
P
V
OUT
P
+1V; output high
-250
-15
-0.2
1.8
3
+0.2
+250
V
V
I
OSD
mA
I
OSDF
+15
mA
2
______________________________________________________________________________________
High-ESD Profibus RS-485 Transceiver
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +5V
Q10%,
T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V
CC
= +5V, T
A
= +25NC.) (Note 2)
PARAMETER
LOGIC INPUTS
Driver Input High
Voltage
Driver Input Low
Voltage
Driver Input
Hysteresis
Driver Input Current
Input Impedance in
Hot Swap
RECEIVER
Input Current (A, B)
Differential Input
Capacitance
Receiver Differential
Threshold Voltage
Receiver Input
Hysteresis
LOGIC OUTPUT
Output High Voltage
Output Low Voltage
Three-State Receiver
Output Current
Receiver Input
Resistance
Receiver Output
Short-Circuit Current
Thermal-Shutdown
Threshold
Thermal-Shutdown
Hysteresis
ESD Protection, A
and B Pins
ESD Protection, All
Other Pins
V
OH
V
OL
I
OZR
R
IN
I
OSR
I
OUT
= -1mA, V
A
- V
B
= V
TH
I
OUT
= 1mA, V
A
- V
B
= -V
TH
0V
P
V
OUT
P
V
CC
-7V
P
V
CM
P
12V
0V
P
V
RO
P
V
CC
-1
48
-110
+110
V
CC
-
1.5
0.4
+1
V
V
FA
kI
mA
I
A,
I
B
C
AB
V
TH
DV
TH
DE = GND, V
CC
= V
GND
or
+5.5V
V
IN
= 12V
V
IN
= -7V
-200
8
-200
-125
15
-50
+250
FA
pF
mV
mV
V
IH
V
IL
V
HYS
I
IN
R
DE
R
RE
DE, DI,
RE
DE, DI,
RE
DE, DI,
RE
DE, DI,
RE
Figure 11 until the first low-to-high transition of DE
occurs
Figure 11 until the first high-to-low transition of
RE
occurs
-1
50
+1
2.0
0.8
V
V
mV
FA
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX14770E
1
5.6
10
kW
Between A and B, DE =
RE
= GND at 6MHz
-7V
P
V
CM
P
12V
V
CM
= 0V
PROTECTION SPECIFICATIONS
V
TS
V
TSH
HBM
IEC 61000-4-2 Air-Gap Discharge to GND
IEC 61000-4-2 Contact Discharge to GND
HBM
+160
15
±35
±20
±10
±2
kV
kV
NC
NC
_______________________________________________________________________________________
3
High-ESD Profibus RS-485 Transceiver
MAX14770E
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +5V
Q10%,
T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V
CC
= +5V, T
A
= +25NC.) (Note 2)
PARAMETER
Driver Propagation
Delay
Differential Driver
Output Skew |t
DPLH
- t
DPHL
|
Driver Output
Transition Skew
|t
t(MLH)
|, |t
t(MHL)
|
Driver Differential
Output Rise or Fall
Time
Maximum Data Rate
Driver Enable to
Output High
Driver Enable to
Output Low
Driver Disable Time
from Low
Driver Disable Time
from High
Driver Enable Skew
Time
Driver Disable Skew
Time
Driver Enable from
Shutdown to Output
High
Driver Enable from
Shutdown to Output
Low
Time to Shutdown
Receiver Propagation
Delay
Receiver Output
Skew
t
DZH
t
DZL
t
DLZ
t
DHZ
|t
ZL
- t
ZH
|
|t
LZ
- t
HZ
|
R
L
= 500I, C
L
= 50pF; Figure 6
R
L
= 500I, C
L
= 50pF; Figure 7
R
L
= 500I, C
L
= 50pF; Figure 7
R
L
= 500I, C
L
= 50pF, Figure 6
R
L
= 500I, C
L
= 50pF; Figures 6 and 7
R
L
= 500I, C
L
= 50pF; Figures 6 and 7
SYMBOL
t
DPLH
t
DPHL
t
DSKEW
CONDITIONS
MIN
TYP
MAX
UNITS
DRIVER SWITCHING CHARACTERISTICS
R
L
= 54I, C
L
= 50pF; Figures 3 and 4
28
ns
R
L
= 54I, C
L
= 50pF; Figures 3 and 4
1.2
ns
t
TSKEW
R
L
= 54I, C
L
= 50pF; Figures 3 and 5
2
ns
t
LH
, t
HL
R
L
= 54I, C
L
= 50pF; Figures 3 and 4
20
15
ns
Mbps
50
50
40
40
8
8
ns
ns
ns
ns
ns
ns
t
DZL(SHDN)
R
L
= 500I, C
L
= 50pF; Figure 7 (Note 6)
100
Fs
t
DZH(SHDN)
t
SHDN
t
RPLH
t
RPHL
t
RSKEW
R
L
= 500I, C
L
= 50pF; Figure 6 (Note 6)
(Note 6)
50
100
800
Fs
ns
RECEIVER SWITCHING CHARACTERISTICS
C
L
= 15pF; Figures 8 and 9 (Note 7)
C
L
= 15pF; Figures 8 and 9 (Notes 7, 8)
28
2
ns
ns
4
______________________________________________________________________________________
High-ESD Profibus RS-485 Transceiver
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +5V
Q10%,
T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V
CC
= +5V, T
A
= +25NC.) (Note 2)
PARAMETER
Maximum Data Rate
Receiver Enable to
Output High
Receiver Enable to
Output Low
Receiver Disable
Time from Low
Receiver Disable
Time from High
Receiver Enable from
Shutdown to Output
High
Receiver Enable from
Shutdown to Output
Low
Time to Shutdown
Note
Note
Note
Note
2:
3:
4:
5:
t
RZH
t
RZL
t
RLZ
t
RHZ
S2 closed; R
L
= 1kI, C
L
= 15pF; Figure 10
S1 closed; R
L
= 1kI, C
L
= 15pF; Figure 10
S1 closed; R
L
= 1kI, C
L
= 15pF; Figure 10
S2 closed; R
L
= 1kI, C
L
= 15pF; Figure 10
S1 closed; R
L
= 1kI, C
L
= 15pF; Figure 10
(Notes 6, 7)
S2 closed; R
L
= 1kI, C
L
= 15pF; Figure 10
(Notes 6, 7)
(Note 6)
50
SYMBOL
CONDITIONS
MIN
20
30
30
30
30
TYP
MAX
UNITS
Mbps
ns
ns
ns
ns
MAX14770E
t
RZL(SHDN)
100
Fs
t
RZH(SHDN)
t
SHDN
100
800
Fs
ns
Devices are production tested at T
A
= +25NC. Specifications over temperature limits are guaranteed by design.
V
ODPP
is the difference in VOD, with the DI at high and DI at low.
DV
OD
and
DV
OC
are the changes in |V
OD
| and |V
OC
|, respectively, with the DI at high and DI at low.
The short-circuit output current applies to peak current just prior to foldback current limiting; the short-circuit foldback out-
put current applies during current limiting to allow a recovery from bus contention.
Note 6:
Shutdown is enabled 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 800ns, the device is guaranteed to
have entered shutdown.
Note 7:
Capacitive load includes test probe and fixture capacitance.
Note 8:
Guaranteed by characterization, not production tested.
_______________________________________________________________________________________
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