Maxim MAX3054ASD ±80v fault-protected/tolerant can transceivers for in-car application Datasheet

19-2687; Rev 0; 11/02
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
The MAX3054/MAX3055/MAX3056 are designed to provide optimal operation for a specified data rate. The
MAX3054 is ideal for high data rates of 250kbps. The
MAX3055 is used for data rates of 125kbps and the
MAX3056 is designed for 40kbps applications. For the
40kbps and 125kbps versions, a built-in slope-control
feature allows the use of unshielded cables, and receiver input filters guarantee high noise immunity.
Applications
Features
♦ Pin and Functionally Compatible with TJA1054
♦ ±80V Fault Protection Suitable for 42V Battery
Systems
♦ Low RFI/Excellent EMC Immunity
♦ Full Wake-Up Capability During Failure Modes
♦ Bus-Failure Management
♦ Support Single-Wire Transmission Mode with
Ground Offset Voltages Up to 1.5V
♦ Thermally Protected
♦ Do Not Disturb the Bus Line when Unpowered
♦ Low-Current Sleep and Standby Mode with WakeUp Through Bus Lines
♦ Up to 250kbps Data Rate (MAX3054)
Ordering Information
PART
TEMP RANGE
DATA RATE
PINPACKAGE
-40°C to +125°C
250kbps
14 SO
MAX3055ASD
-40°C to +125°C
Slew control
125kbps
14 SO
MAX3056ASD
-40°C to +125°C
Slew control
40kbps
14 SO
MAX3054ASD
Automotive
Pin Configuration
Typical Operating Circuit
VBATT +12V
BATTERY
CAN CONTROLLER
+5V
2
3
TXD RXD
7
WAKE
RTH
8
5
STB
6
EN
4
1
ERR
INH
10
VCC
MAX305_
CANH CANL
11
12
GND
BATT
RTL
9
13
TOP VIEW
INH 1
14 BATT
TXD
2
13 GND
RXD
3
12 CANL
ERR 4
100nF
STB 5
MAX3054
MAX3055
MAX3056
11 CANH
10 VCC
EN 6
9
RTL
WAKE 7
8
RTH
14
FAULT
TO ±80V
SO
CAN BUS
________________________________________________________________ Maxim Integrated Products
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.
1
MAX3054/MAX3055/MAX3056
General Description
The MAX3054/MAX3055/MAX3056 are interfaces
between the protocol controller and the physical wires
of the bus lines in a controller area network (CAN). The
devices provide differential transmit capability and
switch to single-wire mode if certain fault conditions
occur. The MAX3054/MAX3055/MAX3056 guarantee
full wake-up capability during failure modes.
The extended fault-protected voltage range of CANH
and CANL bus lines of ±80V allows for use in 42V
automotive applications. Current-limiting and thermalprotection circuits protect the transmitter output stage
against overcurrent faults to prevent destruction of the
transmitter output stage. The CANH and CANL lines are
also protected against electrical transients that may occur
in an automotive environment.
The transceiver provides three low-power modes that
can be entered and exited through pins STB and EN.
An output INH pin can be used for deactivation of an
external voltage regulator.
MAX3054/MAX3055/MAX3056
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
ABSOLUTE MAXIMUM RATINGS
INH Current.......................................................................-0.5mA
Transient Voltage (ISO 7637)................................-200V, +200V*
Continuous Power Dissipation (TA = +70°C)
14-Pin SO (derate 8.3mW/°C above +70°C)................667mW
Operating Temperature Range .........................-40°C to +125°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
(All voltages are referenced to GND)
Supply Voltage (VCC) ...............................................-0.3V to +6V
Battery Voltage (VBATT)..........................................-0.3V to +80V
TXD, RXD, ERR, STB, EN ...........................-0.3V to (VCC + 0.3V)
CANH, CANL ..........................................................-80V to +80V
RTH, RTL ................................................................-0.3V to +80V
RTH, RTL Current ...........................................................±180mA
WAKE .....................................................................-0.3V to +80V
INH ..........................................................-0.3V to (VBATT + 0.3V)
*Pending completion of testing.
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.
DC ELECTRICAL CHARACTERISTICS
(VCC = 5V ±5%, VBATT = +5V to +42V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 5V, VBATT = 14V, R1 = 100Ω
(Figure 2), TA = +25°C.) (Notes 1, 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Dominant normal operating mode, no load,
TXD = 0
16
30
Recessive normal operating mode,
TXD = VCC
4
10
Low-power modes: VTXD = VCC, VBATT = 14V
3
10
µA
54
125
µA
3.5
V
0.8
V
VOLTAGE SUPPLIES
Supply Current
Battery Current
Battery Power on Flag Threshold
ICC
IBATT
VPWRON
mA
Low-power modes at VTRL = VBATT,
VBATT = V WAKE = VINH = 5V to 27V
Low-power modes
5
1.0
STB, EN, AND TXD
High-Level Input Voltage
VIH
Low-Level Input Voltage
VIL
High-Level Input Current
IIH
VIN = 4V
Low-Level Input Current
IIL
VIN = 1V
Supply Voltage—Forced
Standby Mode (Fail-Safe)
2.4
VFS
VBATT = 14V
High-Level Output Voltage
VOH
IOUT = -1mA
Low-Level Output Voltage
VOL
IOUT = 7.5mA
STB and EN
TXD
STB and EN
TXD
-200
V
9
20
-80
-25
4
8
-800
-320
2.75
-100
4.50
µA
µA
V
RXD AND ERR
VCC - 0.5
0
VCC
V
0.9
V
WAKE
Wake-Up Threshold Voltage
Low-Level Input Current
2
VTH(WAKE)
IIL(WAKE)
VSTB = 0V
2.0
2.7
3.4
V
V WAKE = 0V
-10
-4
-1
µA
_______________________________________________________________________________________
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
(VCC = 5V ±5%, VBATT = +5V to +42V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 5V, VBATT = 14V, R1 = 100Ω
(Figure 2), TA = +25°C.) (Notes 1, 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
INH
High-Level Voltage Drop
Leakage Current
∆VH
ILEAK(INH)
INH = -0.18mA, standby mode
Sleep mode, VINH = 0V
0.8
V
5
µA
CANH, CANL
VCC = 5V, no failures and bus failures 1, 2,
5, 9
Differential Receiver Threshold
VDIFF
-3.5
-0.70 ✕ VCC -0.58 ✕ VCC
HYST
No failures and bus failures 1, 2, 5, 9
CANH Recessive Output Voltage
VOCH
TXD = VCC, RTH < 4kΩ
CANL Recessive Output Voltage
VOCL
TXD = VCC, RTH < 4kΩ
VCC - 0.2
CANH Dominant Output Voltage
VOCHDOM
TXD = 0V, R1 = 100Ω
VCC - 1.4
CANL Dominant Output Voltage
VOCLDOM
TXD = 0V, R1 = 100Ω
IO(CANH)
18
IO(CANL)
Voltage Detection Threshold for
Short Circuit to Battery on CANH
VDET(CANH)
Voltage Detection Threshold for
Short Circuit to GND on CANL
Voltage Detection Threshold for
Short Circuit to Battery on CANL
mV
200
V
1.4
VCANH = 0V, TXD = 0V
-150
Low-power modes, VCANH = 0V, VCC = 5V
-10
-86
V
mA
µA
75
Low-power modes, VCANL = 42V,
VBATT = 42V, RTL = open
VCC = 4.75V to 5.25V
mV
V
VCANL = 14V, TXD = 0V
CANL Output Current
-2.9
V
VCC = 4.75V to 5.25V, no failures and bus
failures 1, 2, 5, 9
Differential Receiver Hysteresis
CANH Output Current
-3.2
0.30 ✕ VCC
130
mA
20
µA
0.37 ✕ VCC
V
Low-power modes
1.1
2.5
VDTG(CANL)
Low-power modes
2.5
3.9
V
VDET(CANL)
Normal mode, VCC = 5V
6.4
7.3
8.2
V
CANL Wake-Up Threshold
VTHL(WAKE)
Low-power modes
2.5
3.2
3.9
V
CANH Wake-Up Threshold
VTHH(WAKE)
Low-power modes
1.1
1.8
2.5
V
1.50
1.70
CANH Single-Ended Receiver
Threshold (Failures 4, 6, 7)
VSE(CANH)
CANH Single-Ended Receiver
Hysteresis
HYST
VCC = 5V
VCC = 4.75V to 5.25V
0.30 ✕ VCC
1.85
0.37 ✕ VCC
10
V
mV
_______________________________________________________________________________________
3
MAX3054/MAX3055/MAX3056
DC ELECTRICAL CHARACTERISTICS (continued)
MAX3054/MAX3055/MAX3056
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
DC ELECTRICAL CHARACTERISTICS (continued)
(VCC = 5V ±5%, VBATT = +5V to +42V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 5V, VBATT = 14V, R1 = 100Ω
(Figure 2), TA = +25°C.) (Notes 1, 2)
PARAMETER
SYMBOL
CONDITIONS
VCC = 5V
MIN
TYP
MAX
3.15
3.30
3.45
UNITS
CANL Single-Ended Receiver
Threshold
VSE(CANL)
CANL Single-Ended Receiver
Hysteresis
HYST
Failures 3, 8
10
RTL to VCC Switch
On-Resistance
RSW(RTL)
IO = -10mA
36
100
Ω
RTH to VCC Switch
On-Resistance
RSW(RTH)
IO = 10mA
23
100
Ω
VCC = 4.75V to 5.25V
0.63 ✕ VCC
0.69 ✕ VCC
V
mV
RTL AND RTH
Output Current on Pin RTL
-1.25
-0.65
-0.30
mA
RTL Pullup Current
|IPU(RTL)|
IO(RTL)
Low-power modes, VRTL = 0
Normal and failures 4, 6, 7, RTL = 0V
20
107
200
µA
RTH Pulldown
|IPU(RTH)|
Normal and failures 3, 8, RTL = VCC
20
106
200
µA
THERMAL SHUTDOWN
Shutdown Junction Temperature
Thermal Protection Hysteresis
TJ
TJF6
For shutdown
165
During failure 6—switch off CANL only
140
THYS
°C
15
°C
AC ELECTRICAL CHARACTERISTICS
(VCC = 5V ±5%, VBATT = +5V to +42V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 5V, VBATT = 14V, R1 = 100Ω
(Figure 2), TA = +25°C.) (Notes 1, 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
TRANSITION TIME
CL = 330pF, MAX3054 (250kbps)
CANL and CANH Bus Output
Transition Time Recessive to
Dominant (10% to 90%)
t(r-d)
CANL and CANH Bus Output
Transition Time Dominant to
Recessive (10% to 90%)
t(d-r)
38
CL = 220pF to 3.3nF, MAX3055 (125kbps)
100
700
CL = 560pF to 10nF, MAX3056 (40kbps)
0.7
3.3
CL = 330pF, MAX3054 (250kbps)
130
CL = 220pF to 1nF, MAX3055 (125kbps)
200
1200
CL = 560pF to 3.3nF, MAX3056 (40kbps)
0.5
2.8
ns
µs
ns
µs
PROPAGATION DELAY TXD TO RXD LOW—DOMINANT TRANSMISSION (Figures 1, 2)
No failures, CL = 330pF, MAX3054
(250kbps)
600
Bus failures 1, 2, 5, 9,
CL = 330pF, MAX3054 (250kbps)
750
No failures and bus failures 1, 2, 5, 9,
CL = 1nF, MAX3055 (125kbps)
1.5
No failures and bus failures 1, 2, 5, 9,
CL = 3.3nF, MAX3056 (40kbps)
4.7
ns
Differential Reception
4
tPDLD
_______________________________________________________________________________________
µs
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
(VCC = 5V ±5%, VBATT = +5V to +42V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 5V, VBATT = 14V, R1 = 100Ω
(Figure 2), TA = +25°C.) (Notes 1, 2)
PARAMETER
Single-Ended Reception
SYMBOL
tPDLSE
CONDITIONS
MIN
TYP
MAX
UNITS
Bus failures 3, 4, 6, 7, 8,
CL = 330pF, MAX3054 (250kbps)
750
ns
Bus failures 3, 4, 6, 7, 8,
CL = 1nF, MAX3055 (125kbps)
1. 5
Bus failures 3, 4, 6, 7, 8,
CL = 3.3nF, MAX3056 (40kbps)
4.7
µs
PROPAGATION DELAY TXD TO RXD HIGH—RECESSIVE TRANSMISSION (Figures 1, 2)
Differential Reception
Single-Ended Reception
tPDHD
tPDHSE
No failures and bus failures 1, 2, 5, 9,
CL = 330pF, MAX3054 (250kbps)
950
No failures and bus failures 1, 2, 5, 9,
CL = 1nF, MAX3055 (125kbps)
1.9
No failures and bus failures 1, 2, 5, 9,
CL = 3.3nF, MAX3056 (40kbps)
5.95
Bus failures 3, 4, 6, 7, 8,
CL = 330pF, MAX3054 (250kbps)
950
Bus failures 3, 4, 6, 7, 8,
CL = 1nF, MAX3055 (125kbps)
1.9
Bus failures 3, 4, 6, 7, 8,
CL = 3.3nF, MAX3056 (40kbps)
5.95
ns
µs
ns
µs
WAKE-UP TIMING
Minimum Time for Wake-Up on
CANL and CANH or WAKE
8
t WAKE
38
µs
FAILURES TIMING
Normal and
low-power mode
Failures 3 and 8 Detection Time
Failures 4 and 7 Detection Time
Failure 6 Detection Time
tDET
Normal and
low-power mode
Normal mode
MAX3054 (250kbps),
MAX3055 (125kbps)
1.9
5.7
9.5
MAX3056 (40kbps)
5.5
16.5
27.0
MAX3054 (250kbps),
MAX3055 (125kbps)
0.3
1
1.9
MAX3056 (40kbps)
1.0
3.2
5.5
MAX3054 (250kbps),
MAX3055 (125kbps)
0.35
1.1
1.85
MAX3056 (40kbps)
0.93
2.97
5.00
ms
_______________________________________________________________________________________
5
MAX3054/MAX3055/MAX3056
AC ELECTRICAL CHARACTERISTICS (continued)
MAX3054/MAX3055/MAX3056
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
AC ELECTRICAL CHARACTERISTICS (continued)
(VCC = 5V ±5%, VBATT = +5V to +42V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 5V, VBATT = 14V, R1 = 100Ω
(Figure 2), TA = +25°C.) (Notes 1, 2)
PARAMETER
SYMBOL
CONDITIONS
Normal and
low-power mode
Failures 3 and 8 Recovery Time
Normal mode
Failures 4 and 7 Recovery Time
tREC
Low-power mode
Failure 6 Recovery Time
Minimum Hold Time of
Go-to-Sleep Command
Disable Time of TXD Permanent
Dominant Timer
Normal mode
MIN
TYP
MAX
MAX3054 (250kbps),
MAX3055 (125kbps)
0.36
1.14
1.90
MAX3056 (40kbps)
1.0
3.2
5.5
MAX3054 (250kbps)
1.7
5.6
9.5
MAX3055 (125kbps)
7
23
38
MAX3056 (40kbps)
22
70
119
MAX3054 (250kbps),
MAX3055 (125kbps)
0.35
1.1
1.85
MAX3056 (40kbps)
1.0
3.2
5.5
MAX3054 (250kbps),
MAX3055 (125kbps)
150
525
900
MAX3056 (40kbps)
390
1445
2500
5
50
MAX3054 (250kbps),
MAX3055 (125kbps)
0.9
4.5
MAX3056 (40kbps)
2.34
12.50
tHMIN
tDIS(TXD)
VTXD = 0
Pulse Count Difference for
Failures 1, 2, 5, 9 Detection (ERR
Becomes Low)
UNITS
ms
µs
ms
µs
µs
ms
4
Count
Pulse Count Difference for
Failures 1, 2, 5, 9 Recovery (ERR
Becomes High)
3
4
5
Note 1: All currents into the device are positive; all currents out of the device are negative. All voltages are referenced to device
ground, unless otherwise noted.
Note 2: Failure modes 1 through 9 are explained in Table 1 and in the Detailed Description section.
6
_______________________________________________________________________________________
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
+5V
VCC
VTXD
10
GND
7
5V
3.6V
1.4V
0
VCANL
VCANH
6
VCC
2
5
EN
STB
RTH
WAKE
CANL
TXD
8
R1
CL
R1
CL
12
2.2V
MAX305_
1
-3.2V
-5V
VDIFF
CANH
INH
VBATT
14
VRXD
VCC/2
RTL
BATT
9
CBYPASS
ERR
GND
4
tPDL
11
RXD
13
3
tPDH
VDIFF = CANH - CANL
CX = 15pF
PROBE CAP INCLUDED
Figure 1. Timing Diagram for Dynamic Characteristics
Figure 2. Test Circuit for Dynamic Characteristics
+5V
+5V
10
VCC
7
6
5
EN
10
STB
RTH
WAKE
8
125Ω
VCC
CL
7
6
5
EN
STB
RTH
WAKE
511Ω
8
125Ω
1nF
511Ω
1nF
2
CANL
TXD
12
2
11
1
MAX305_
1
511Ω
+12V
14
RTL
BATT
CBYPASS
ERR
4
GND
13
12
GENERATOR
MAX305_
CANH
INH
CANL
TXD
RXD
3
11
511Ω
+12V
9
14
125Ω
1nF
CANH
INH
CL
CX = 15pF
PROBE CAP INCLUDED
Figure 3. Test Circuit for Typical Operating Characteristics
RTL
BATT
CBYPASS
ERR
4
GND
13
RXD
3
9
125Ω
1nF
CX = 15pF
PROBE CAP INCLUDED
Figure 4. Test Circuit for Automotive Transients
_______________________________________________________________________________________
7
MAX3054/MAX3055/MAX3056
Timing Diagram/Test Circuits
Typical Operating Characteristics
(VCC = 5V, VBATT = +12V, RTL = RTH = 511Ω, R1 = 125Ω, and TA = +25°C; see Figure 3.)
MAX3054
SUPPLY CURRENT vs. DATA RATE
10
5
36
TA = -40°C
34
-7
26
59
92
50 100 150 200 250 300 350 400 450 500
0
25
50
75
100
DATA RATE (kbps)
DATA RATE (kbps)
MAX3056
SUPPLY CURRENT vs. DATA RATE
MAX3054 RECEIVER PROPAGATION
DELAY vs. TEMPERATURE
MAX3055 RECEIVER PROPAGATION
DELAY vs. TEMPERATURE
34
33
400
RECESSIVE
350
300
DOMINANT
250
600
20
40
30
500
RECESSIVE
DOMINANT
300
200
200
10
CL = 1nF
400
-50
-15
20
55
90
-50
125
-15
20
55
90
DATA RATE (kbps)
TEMPERATURE (°C)
TEMPERATURE (°C)
MAX3056 RECEIVER PROPAGATION
DELAY vs. TEMPERATURE
MAX3054 DRIVER PROPAGATION
DELAY vs. TEMPERATURE
MAX3055 DRIVER PROPAGATION
DELAY vs. TEMPERATURE
1.5
1.0
RECESSIVE
0.5
0
CL = 330pF
175
DOMINANT
150
RECESSIVE
125
20
55
TEMPERATURE (°C)
90
125
CL = 1nF
DOMINANT
600
500
RECESSIVE
400
300
100
-15
700
125
MAX3054/MAX3055/MAX3056 toc09
DOMINANT
200
DRIVER PROPAGATION DELAY (µs)
CL = 3.3nF
RECEIVER PROPAGATION DELAY (ns)
MAX3054/MAX3055/MAX3056 toc07
2.0
125
MAX3054/MAX3055/MAX3056 toc06
CL = 330pF
RECEIVER PROPAGATION DELAY (ns)
TA = -40°C
MAX3054/MAX3055/MAX3056 toc05
35
450
RECEIVER PROPAGATION DELAY (ns)
36
TA = +25°C
MAX3054/MAX3055/MAX3056 toc04
37
TA = +125°C
-50
TA = -40°C
34
TEMPERATURE (°C)
38
0
TA = +25°C
35
32
0
125
TA = +125°C
33
32
-40
SUPPLY CURRENT (mA)
35
36
33
MAX3056
0
8
TA = +25°C
37
MAX3054/MAX3055/MAX3056 toc03
TA = +125°C
MAX3054/MAX3055/MAX3056 toc08
SLEW RATE (V/µs)
15
MAX3054/MAX3055/MAX3056 toc02
MAX3055
37
SUPPLY CURRENT (mA)
MAX3054/MAX3055/MAX3056 toc01
20
MAX3055
SUPPLY CURRENT vs. DATA RATE
SUPPLY CURRENT (mA)
SLEW RATE vs. TEMPERATURE
RECESSIVE TO DOMINANT
RECEIVER PROPAGATION DELAY (µs)
MAX3054/MAX3055/MAX3056
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
-50
-15
20
55
TEMPERATURE (°C)
90
125
-50
-15
20
55
TEMPERATURE (°C)
_______________________________________________________________________________________
90
125
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
RECEIVER OUTPUT LOW
vs. OUTPUT CURRENT
2.5
2.5
TA = +125°C
DOMINANT
2.0
1.5
TA = +25°C
1.0
3.0
2.4
VOLTAGE RXD (V)
RECESSIVE
3.0
MAX3054/MAX3055/MAX3056 toc11
3.0
2.0
TA = +125°C
1.8
TA = +25°C
1.2
0.6
0.5
TA = -40°C
1.5
TA = -40°C
0
-15
20
55
90
0
125
0
TEMPERATURE (°C)
5
10
DIFFERENTIAL VOLTAGE
vs. LOAD RESISTANCE
20
25
30
0
3
TA = +125°C
TA = +25°C
6
9
12
15
18
OUTPUT CURRENT (mA)
MAX3054
RECEIVER PROPAGATION DELAY
5
4
15
OUTPUT CURRENT (mA)
MAX3054/MAX3055/MAX3056 toc13
-50
DIFFERENTIAL VOLTAGE (V)
DRIVER PROPAGATION DELAY (µs)
CL = 3.3nF
VOLTAGE RXD (V)
MAX3054/MAX3055/MAX3056 toc10
3.5
RECEIVER OUTPUT HIGH
vs. OUTPUT CURRENT
MAX3054/MAX3055/MAX3056 toc12
MAX3056 DRIVER PROPAGATION
DELAY vs. TEMPERATURE
3
MAX3054/MAX3055/MAX3056 toc14
DIFFERENTIAL
INPUT
5V/div
TA = -40°C
2
RXD
5V/div
1
0
0
100
200
300
400
500
200ns/div
LOAD RESISTANCE (Ω)
MAX3056
RECEIVER PROPAGATION DELAY
MAX3055
RECEIVER PROPAGATION DELAY
MAX3054/MAX3055/MAX3056 toc16
MAX3054/MAX3055/MAX3056 toc15
400ns/div
DIFFERENTIAL
INPUT
5V/div
DIFFERENTIAL
INPUT
5V/div
RXD
5V/div
RXD
5V/div
1µs/div
_______________________________________________________________________________________
9
MAX3054/MAX3055/MAX3056
Typical Operating Characteristics (continued)
(VCC = 5V, VBATT = +12V, RTL = RTH = 511Ω, R1 = 125Ω, and TA = +25°C; see Figure 3.)
MAX3054/MAX3055/MAX3056
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
Typical Operating Characteristics (continued)
(VCC = 5V, VBATT = +12V, RTL = RTH = 511Ω, R1 = 125Ω, and TA = +25°C; see Figure 3.)
DRIVER PROPAGATION DELAY
RECESSIVE TO DOMINANT
TXD-TO-RXD PROPAGATION DELAY
DOMINANT TO RECESSIVE
DRIVER PROPAGATION DELAY
DOMINANT TO RECESSIVE
MAX3054/MAX3055/MAX3056 toc17
MAX3054/MAX3055/MAX3056 toc19
MAX3054/MAX3055/MAX3056 toc18
TXD
TXD
5V/div
TXD
5V/div
MAX3056
MAX3054
MAX3055
MAX3055
MAX3054
MAX3056
MAX3056
MAX3055
MAX3054
1µs/div
1µs/div
1µs/div
TXD-TO-RXD PROPAGATION DELAY
RECESSIVE TO DOMINANT
MAX3056 CAN BUS AT 40kbps
MAX3054/MAX3055/MAX3056 toc20
MAX3054/MAX3055/MAX3056 toc21
TXD
CANH - CANL
5V/div
MAX3054
MAX3055
FFT
1V/div
MAX3056
1µs/div
4µs/div
MAX3055 CAN BUS AT 125kbps
MAX3054 CAN BUS AT 250kbps
MAX3054/MAX3055/MAX3056 toc22
2µs/div
10
MAX3054/MAX3055/MAX3056 toc23
CANH - CANL
5V/div
CANH - CANL
10V/div
FFT
1V/div
FFT
1V/div
400ns/div
______________________________________________________________________________________
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
PIN
NAME
1
INH
Inhibit Output. Inhibit output is for switching an external voltage regulator if a wake-up signal occurs.
FUNCTION
2
TXD
Transmit Data Input
3
RXD
Receive Data Output
4
ERR
Error. Wake-up and power-on indication output; active low in normal operating mode when the bus
has a failure and in low-power modes (wake-up signal or power-on standby).
5
STB
Standby. The digital control signal input (active low) defines, together with input signal on pin EN, the
state of the transceiver (in normal and low-power modes).
6
EN
Enable. The digital control signal input defines, together with input signal on pin STB, the state of the
transceiver (in normal and low-power modes).
7
WAKE
8
RTH
Termination Resistor. Termination resistor connection for CANH bus.
9
RTL
Termination Resistor. Termination resistor connection for CANL bus.
10
VCC
Supply Voltage. Bypass to ground with a 0.1µF capacitor.
11
CANH
12
CANL
Low-Level Voltage Bus Line
13
GND
Ground
14
BATT
Battery Supply. Bypass to ground with a 0.1µF capacitor.
Wake-Up. Local wake-up signal input; falling and rising edges are both detected.
High-Level Voltage Bus Line
Detailed Description
The MAX3054/MAX3055/MAX3056 interface between
the protocol controller and the physical wires of the bus
lines in a CAN. The devices provide differential transmit
capability and switch to single-wire mode if certain fault
conditions occur (see the Failure Management section).
The MAX3054/MAX3055/MAX3056 guarantee full wakeup capability during failure modes.
The extended fault-protection range of CANH and
CANL bus lines (±80V) allows for use in 42V automotive
applications. A current-limiting circuit protects the
transmitter output stage against overcurrent faults. This
feature prevents destruction of the transmitter output
stage. If the junction temperature exceeds a value of
approximately +165°C, the transmitter output stages
are disabled. The CANH and CANL lines are also protected against electrical transients, which can occur in
an automotive environment.
The transceiver provides three low-power modes that
can be entered and exited through pins STB and EN.
An output INH pin can be used for deactivation of an
external voltage regulator.
The MAX3054/MAX3055/MAX3056 are designed to
provide optimal operation for a specified data rate. The
MAX3054 is ideal for high data rates of 250kbps. The
MAX3055 is used for data rates of 125kbps, and the
MAX3056 is designed for 40kbps applications. For the
40kbps and 125kbps versions, the built-in slope-control
feature allows the use of unshielded cables and receiver
input filters guarantee high noise immunity.
Normal Operation Mode
Transmitter
The transmitter converts a single-ended input (TXD)
from the CAN controller to differential outputs for the
bus lines (CANH, CANL).
Receiver
The receiver takes differential input from the bus lines
(CANH, CANL) and converts this data as a singleended output (RXD) to the CAN controller. It consists of
a comparator that senses the difference ∆V = (CANH CANL) with respect to an internal threshold.
BATT
The main function of BATT is to supply power to the
device when vehicle battery voltage is supplied.
BATT can handle up to +80V making it ideal for 42V
automotive systems allowing power-up of the device
when the ignition is turned on.
______________________________________________________________________________________
11
MAX3054/MAX3055/MAX3056
Pin Description
BATT
10
VCC
9
RTL
INH 1
THERMAL
SHUTDOWN
WAKE-UP
STANDBY
CONTROLLER
WAKE 7
STB 5
EN 6
11
CANH
12
CANL
8
RTH
TXD 2
DRIVER
IPD
ERR 4
FAULT DETECTION
FILTER
4ms
FILTER
MAX3054/MAX3055/MAX3056
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
GND
RXD 3
RECEIVER
MAX305_
Figure 5. Block Diagram
INH
Inhibit is an output that allows for the control of an external voltage regulator. On a wake-up request or power-up
on BATT, the transceiver sets the output INH high. This
feature enables the external voltage regulator to be shut
down during sleep mode to reduce power consumption.
INH is floating while entering the sleep mode and stays
floating during the sleep mode. If INH is left floating, it is
not set to a high level again until the following events
occur:
• Power-on (VBATT switching on at cold start)
• Rising or falling edge on WAKE
• Dominant signal longer than 38µs during EN or STB
at low level
The signals on STB and EN are internally set to a low
level when VCC is below a certain threshold voltage
providing fail-safe functionality.
After power-on (VBATT switched on) the signal on INH
becomes HIGH and an internal power-on flag is set.
This flag can be read in the power-on standby mode
through ERR (STB = 1, EN = 0) and is reset by entering
the normal operating mode.
12
ERR
ERR is a wake-up and power-on indicator, as well as an
error detector. Upon power-up, wake-up, or when a
bus failure is detected, the output signal on ERR
becomes LOW. Upon error recovery, the output signal
on ERR is set HIGH.
STB
STB is the standby digital control signal into the logic
controller. This is an active-low input that is used with
EN to define the status of the transceiver in normal and
low-power modes.
EN
EN is the enable digital control signal into the logic controller used in conjunction with STB to define the status
of the transceiver in normal and low-power modes.
WAKE
WAKE is an input to the logic controller within the
device to signal a wake-up condition. If WAKE receives
a positive or negative pulse for a period longer than
tWAKE, wake-up occurs.
______________________________________________________________________________________
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
Failure Management
Thermal Shutdown
If the junction temperature exceeds +165°C, the driver is
switched off. Thermal hysteresis is 15°C, disabling thermal shutdown once the temperature reaches +150°C.
The failure detector is fully active in normal operating
mode. After the detection of a single failure, the detector switches to the appropriate state (see Table 1).
Overcurrent Protection
A current-limiting circuit protects the transmitter output
stage against a short circuit to a positive and negative
battery voltage. Although the power dissipation increases
during this fault condition, this feature prevents destruction of the transmitter output stage.
The differential receiver threshold voltage is set to -3.2V
typically (VCC = 5V). This ensures correct reception
with a noise margin as high as possible in the normal
operating mode and in the event of failures 1, 2, 5, and 9.
If any of the wiring failures occur, the output signal on
pin ERR becomes LOW after detection. On error recovery, the output signal on pin ERR becomes HIGH.
Table 1. Failure States
FAILURE
DESCRIPTION
MODE
1
CANH wire interrupted
Normal
2
CANL wire interrupted
Normal
3
CANH short circuited to battery
4
CANL short circuited to ground
All
5
CANH short circuited to ground
Normal
6
CANL short circuited to battery
Normal
7
CANL mutually short circuited to CANH
8
CANH short circuited to VCC
All
9
CANL short circuited to VCC
Normal
All
All
Failure 1—CANH Wire Interrupted (Normal Mode Only)
MODE
DESCRIPTION
Detection
The external termination resistance connected to the RTH pin provides an instantaneous pulldown of the open
CANH line to GND. Detection is provided, sensing the pulse-count difference between CANH and CANL (pulse
count = 4).
Receiver
The receiver remains in differential mode. No received data lost.
Driver
Driver remains in differential mode. No transmission data lost.
Recovery
Recovery is provided sensing the pulse-count difference between CANH and CANL after the detection of four
consecutive pulses.
Failure 2—CANL Wire Interrupted (Normal Mode Only)
MODE
Detection
DESCRIPTION
The external termination resistance connected to the RTL pin provides an instantaneous pullup of the CANL line to
VCC. Detection is provided, sensing the pulse-count difference between CANL and CANH (pulse count = 4).
Receiver
The receiver remains in differential mode. No received data lost.
Driver
Driver remains in differential mode. No transmission data lost.
Recovery
Recovery is provided, sensing the pulse-count difference between CANL and CANH after the detection of four
consecutive pulses.
______________________________________________________________________________________
13
MAX3054/MAX3055/MAX3056
Driver Output Protection
MAX3054/MAX3055/MAX3056
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
Table 1. Failure States (continued)
Failure 3—CANH Short Circuited to Battery
MODE
DESCRIPTION
Detection
Sensing a permanent dominant condition on CANH for a timeout period.
Receiver
Receiver switches to single ended on CANL.
Driver
CANH and RTH are both switched off (high impedance) and transmission continues on CANL after timeout.
Recovery
When the short is removed, the recessive bus voltage is restored. If the differential voltage remains below the
recessive threshold level for the timeout period, reception and transmission switch back to the differential mode.
Failure 4—CANL Short Circuited to GND
MODE
DESCRIPTION
Detection
Sensing a permanent dominant condition for a timeout period.
Receiver
Receiver switches to single ended on CANH.
Driver
CANL and RTL are both switched off (high impedance) and transmission continues on CANH after timeout.
Recovery
When the short is removed, the recessive bus voltage is restored. If the differential voltage remains below the
recessive threshold level for the timeout period, reception and transmission switch back to the differential mode.
Failure 5—CANH Short Circuited to Ground or Below Ground (Normal Mode Only)
MODE
DESCRIPTION
Detection
Detection is provided, sensing the pulse-count difference between CANH and CANL (pulse count = 4).
Receiver
Receiver remains in differential mode. No received data lost.
Driver
RTH remains on and CANH remains enabled.
Recovery
Recovery is provided, sensing the edge-count difference between CANH and CANL after the detection of four
consecutive pulses.
Failure 6—CANL Short Circuited to Battery (Normal Mode Only)
MODE
DESCRIPTION
Detection
Detected by a comparator for CANL > 7.3V after a timeout period.
Receiver
Receiver switches to single ended on CANH after timeout.
Driver
RTL is switched off after timeout. CANH remains active.
Recovery
Sensing CANL < 7.3V after the timeout period.
Failure 7—CANL Mutually Short Circuited to CANH
MODE
DESCRIPTION
Detection
Sensing a permanent dominant condition on the differential comparator (CANH - CANL > -3.2V) for the timeout
period.
Receiver
Receiver switches to CANH single-ended mode after timeout.
Driver
CANL and RTL are both switched off after timeout. Transmission remains ongoing on CANH.
Recovery
When the short is removed, the recessive bus voltage is restored (RTL on if CANH - CANL < -3.2V) but CANL still
remains disabled and ERR = 0. If the differential voltage remains below the recessive threshold level (CANH CANL < -3.2V) for the timeout period, reception and transmission switch back to the differential mode.
14
______________________________________________________________________________________
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
MODE
DESCRIPTION
Detection
Sensing a permanent dominant condition on CANH for a timeout period.
Receiver
Receiver switches to single ended on CANL.
Driver
CANH and RTH are both switched off (high impedance) and transmission continues on CANL after timeout.
Recovery
When the short is removed, the recessive bus voltage is restored. If the differential voltage remains below the
recessive threshold level for the timeout period, reception and transmission switch back to the differential mode.
Failure 9—CANL Short Circuited to Vcc (Normal Mode Only)
MODE
DESCRIPTION
Detection
Detection is provided, sensing the pulse-count difference between CANL and CANH (pulse count = 4).
Receiver
Receiver remains in differential mode. No received data lost.
Driver
Driver remains in differential mode. No transmission data lost.
Recovery
Recovery is provided, sensing the pulse-count difference between CANL and CANH after the detection of four
consecutive pulses.
Table 2. Summary of the Driver Outputs and Internal Switches State During Fault
Conditions
DRIVER OUTPUTS STATE
FAILURE NO.
DESCRIPTION
MODE
INTERNAL SWITCHES STATE
CANH
CANL
No failure
—
Normal
RTH, RTL on
Enabled
Enabled
No failure
—
Low power
RTH, I_RTL on
Disabled
Disabled
1
CANH wire interrupted
Normal
RTH, RTL on
Enabled
Enabled
2
CANL wire interrupted
Normal
RTH, RTL on
Enabled
Enabled
3
CANH short to BATT
All
RTH off
Disabled
Enabled
4
CANL short to GND
All
RTL or I_RTL off
Enabled
Disabled
5
CANH short to GND
Normal
RTH, RTL on
Enabled
Enabled
6
CANL short to BATT
Normal
RTL off, RTH on
Enabled
Enabled
7
CANL short to CANH
All
RTL or I_RTL off
Enabled
Disabled
8
CANH short to VCC
All
RTH off
Disabled
Enabled
9
CANL short to VCC
Normal
RTH, RTL on
Enabled
Enabled
Note: The RTH-pulldown current switch and the RTL-pullup current switch are closed in normal mode with or without fault conditions,
open in sleep mode.
______________________________________________________________________________________
15
MAX3054/MAX3055/MAX3056
Table 1. Failure States (continued)
Failure 8—CANH Short Circuited to Vcc
MAX3054/MAX3055/MAX3056
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
To prevent false wake-up due to transients or RF fields,
the wake-up voltage levels have to be maintained for more
than 38µs. In the low-power modes, the failure detection
circuit remains partly active to prevent increased power
consumption in the event of failures 3, 4, 7, and 8.
Low-Power Modes
The transceiver provides three low-power modes that can
be entered or exited through pins STB and EN (Table 3).
Sleep Mode
The sleep mode is the mode with the lowest power consumption. INH is switched to high impedance for deactivation of the external voltage regulator. CANL is biased
to the battery voltage through RTL. If the supply voltage
is provided, RXD and ERR signal the wake-up interrupt.
Applications Information
The MAX3054/MAX3055/MAX3056 are capable of sustaining a network of up to 32 transceivers on a single
bus. The fault-tolerant transceivers are designed to
operate at a total termination resistance of 100Ω. Both
CANH and CANL lines are terminated with 100Ω. Since
the total termination resistance of the system is distributed over the entire bus, each of the transceivers contributes only part of the total 100Ω termination. The
values of the termination resistors RTL and RTH vary
according to the size of the system and need to be calculated. It is not required that each transceiver be terminated with the same value, the total termination need
only be a total 100Ω.
The minimum termination resistor value allowed for
each transceiver is 500Ω, due to the driving capability
of RTH and RTL. This makes it impossible to achieve a
total termination resistance of 100Ω for systems smaller
than five transceivers. Typically this does not create a
problem because smaller systems usually have shorter
bus cables and have no problem with higher total termination resistance.
To reduce EMI in the case of an interrupted bus wire it
is recommended not to exceed 6kΩ termination resistance at a single transceiver even though a higher
value is specified.
Standby Mode
The standby mode reacts the same as the sleep mode,
but with a HIGH level on INH. Standby mode can be
used when the external voltage regulator needs to be
kept active during low-power operation.
Power-On Standby Mode
The power-on standby mode behaves similarly to the
standby mode with the battery power-on flag of the
wake-up interrupt signal on ERR. This mode is only for
reading the power-on flag. INH can be high or low in
the power-on standby mode. When the device goes
from standby mode to power-on standby mode, INH is
HIGH. When the device goes from sleep mode to
power-on standby mode, INH is low.
Wake-Up
Wake-up requests are recognized by the transceiver
when a dominant signal is detected on either bus line
or if WAKE detects a pulse for more than 38µs. On a
wake-up request, INH is set high to activate an external
voltage regulator.
If VCC is provided, the wake-up request can be read on
the ERR or RXD outputs.
Table 3. Low-Power Modes
MODE
STB
EN
Go-to-Sleep
Command
0
1
ERR
RXD
LOW
HIGH
LOW
HIGH
RTL
SWITCHED TO
Wake-up
interrupt signal
(Notes 2 and 3)
—
Wake-up
interrupt signal
(Notes 2 and 3)
—
VBATT
Sleep
0
0 (Note 1)
Standby
0
0
Power-On
Standby
1
0
VBATT power-on
flag
—
Wake-up
interrupt signal
(Notes 2 and 3)
—
VBATT
Normal
Operating
1
1
Error flag
No error flag
Dominant
received data
Recessive
received data
VCC
Note 1: In case the go-to-sleep command was used before.
Note 2: If the supply voltage VCC is present.
Note 3: Wake-up interrupts are released when entering the normal operating mode.
16
______________________________________________________________________________________
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
The MAX3054/MAX3055/MAX3056 require no special
layout considerations beyond common practices.
Bypass VCC to GND with a 0.1µF ceramic capacitor
mounted close to the IC with short lead lengths and
wide trace widths.
Chip Information
TRANSISTOR COUNT: 1300
PROCESS: BiCMOS
______________________________________________________________________________________
17
MAX3054/MAX3055/MAX3056
Reduced EMI and Reflections
Due to internal slope control for the MAX3055/
MAX3056, the CANH and CANL outputs are slew-rate
limited. This minimizes EMI and reduces reflections
caused by improperly terminated cables. In general, a
transmitter’s rise time relates directly to the length of an
unterminated stub, which can be driven with only minor
waveform reflections. The following equation expresses
this relationship conservatively:
Length = tRISE / (15ns/ft)
where tRISE is the transmitter’s rise time.
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
14L SOIC.EPS
MAX3054/MAX3055/MAX3056
±80V Fault-Protected/Tolerant CAN
Transceivers for In-Car Applications
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.
18 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2002 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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