EVALUATION KIT AVAILABLE
MAX31953/MAX31963
Octal Industrial Digital Input with
Isolated SPI Interface
General Description
The MAX31953/MAX31963 translates eight current-sinking,
12V, 24V, or 48V industrial inputs to a galvanically isolated,
SPI-compatible, serial output that interfaces with 3V to 5.5V
logic. The galvanic isolation is certified to 500V
RMS
for 60
seconds, with creepage and clearance distances of 1.4 mm.
The input side (field-side) of the device includes a 5V logic
serial input for daisy-chaining data from other devices (such
as the MAX31911/MAX31913) through the devices’ isolated
serial port, eliminating the need for additional isolators. The
field-side of the devices requires a single 4.5V to 5.5V
supply. This power is supplied either directly or through the
integrated voltage regulator. The MAX31953 includes a
linear voltage regulator, while the MAX31963 includes an
efficient buck regulator that requires an external inductor.
Both regulators accept input voltages from 7V to 36V. The
logic-side of the devices operate from a single 3V to 5.5V
supply, which also sets the SPI logic level.
Benefits and Features
●
Reduced Power and Heat Dissipation
• Accurate Input-Current Limiters
• Energyless Field-Side LED Drivers
• Integrated Buck Regulator (MAX31963)
●
Configurability Enables Wide Range of Standard and
Custom Applications
• Eight High-Voltage Input Channels (36V Max)
•
Configurable IEC 61131-2 Type 1, 2, 3 Inputs
•
Configurable Input Current-Limiting From 0.5mA to
6mA
• Selectable 0, 25µs, 0.75ms, or 3ms Input
Debounce Filtering
• High-Speed, 2µs Update Rate
●
High Integration Reduces BOM Count and Board
Space
• Integrated 500V
RMS
Galvanic Isolation
• Integrated 5V LDO (MAX31953)
• Daisy-Chain Capability Eliminates Isolators
• 48-Pin TSSOP Package
• Integrated Overtemperature Monitor and Thermal
Shutdown
• Integrated Field-Supply Voltage Monitors
• 5-Bit CRC Code Generation and Transmission For
Error Detection
• ±15kV ESD HBM Immunity on IN1–IN8
• -40°C to +125°C Ambient Operating Temperature
●
Operates Directly From Field Supply in 12V and 24V
Systems
• Integrated Voltage Regulator Accepts 7V to 36V
• Option to Power Directly From a 5V Supply
●
SPI Interface Flexibility
• Compatible with 3.3V or 5V Logic
• Daisy-Chain Data From the Field-Side
Applications
●
●
●
●
Programmable Logic Controllers
Industrial Automation
Process Automation
Building Automation
Standard Compliance (Pending)
●
UL1577
Ordering Information
appears at end of data sheet.
19-7684; Rev 0; 6/15
MAX31953/MAX31963
Octal Industrial Digital Input with
Isolated SPI Interface
Typical Application Circuit
2.2kΩ
IN1
LED1
2.2kΩ
IN2
LED2
GNDL
VDDL
0.1µF
1µF
3.0 TO 5.5V
INF
(INPUT-FIELD)
2.2kΩ
1nF
INP
(INPUT-PIN)
IN8
LED8
VDD
DOUT
MISO
CLK
GPO
GPI OR INT
GPO
GPO
µC, ASIC,
OR FPGA
BACKPLANE
INTERFACE
15kΩ
MAX31953
MAX31963
IREF
GNDF
MODESEL
CLK
CS
FAULT
DB0L
150Ω
10µF
VDD24F
MAX31963 ONLY
LX
VDD5F
DB1L
68µH
GND
0.1µF
10µF
DB0F
DB1F
DINF
CLKO
CSO
FIELD-
SIDE
LOGIC-
SIDE
DB0
5VOUT
15kΩ
RIREF
GND
DB1
SOUT
CLK
CS
VDD24VF
2.2kΩ
IN1
RT1
MAX31913
ISOLATION
BARRIER
16-CHANNEL TYPE 1 OR 3
DIGITAL INPUT MODULE
2.2kΩ
IN2
RT2
2.2kΩ
IN8
RT8
MODSEL
SIN
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MAX31953/MAX31963
Octal Industrial Digital Input with
Isolated SPI Interface
Absolute Maximum Ratings
VDDL to GNDL .......................................................-0.3V to +6V
VDD5F to GNDF .....................................................-0.3V to +6V
VDD24F to GNDF .................................................-0.3V to +45V
GNDL to GNDF for 1 min .............................................500V
RMS
DB0L, DB1L,
CS
, CLK to GNDL.............................-0.3V to +6V
DOUT, FAULT to GNDL..........................-0.3V to (VDDL + 0.3V)
Short-circuit duration FAULT, DOUT
to VDDL or GDL ....................................................Continuous
DB0F, DB1F, DINF, MODESEL,
CLKO,
CSO
, IREF to GNDF .......... -0.3V to (VDD5F + 0.3V)
Short-circuit duration CLKO,
CSO
to VDD5F or GNDF ...............................................Continuous
IN1–IN8 to GNDF ..................................................0.3V to +45V
IN1–IN8 to GNDF with 2.2kΩ series resistor
.........-45V to +45V
LED1 – LED8 to GNDF ...........................................-0.3V to +6V
Continuous Power Dissipation (T
A
= +70°C)
48-pin TSSOP
(derate at 54.2mW/°C above +70°C) ........................4333mW
Operating Temperature Range
Ambient Temperature ..................................................+125°C
Junction Temperature ..................................................+150°C
Storage Temperature Range ............................ -65°C to +150°C
Lead Temperature (soldering, 10s) ................................. +300°C
Soldering (reflow) ............................................................+260°C
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.
Package Thermal Characteristics
(Note 1)
TSSOP
Junction-to-Ambient Thermal Resistance (θ
JA
) .....18.46°C/W
Junction-to-Case Thermal Resistance (θ
JC
) ............1.82°C/W
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.maximintegrated.com/thermal-tutorial.
DC Electrical Characteristics
V
VDDL
- V
GNDL
= +3.0V to +5.5V, V
VDD5F
- V
GNDF
= +4.5V to +5.5V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. C
L
= 15pF. Typical
values are at V
VDDL
- V
GNDL
= +3.3V, V
VDD5F
- V
GNDF
= +5V, VDD24F connected to VDD5F, V
GNDL
- V
GNDF
= 0V, and T
A
= +25°C.
(Note 2)
PARAMETER
POWER SUPPLIES
Logic Supply Voltage
VDDL
I
VDDL
CS
= GNDL,
CLK = 2MHz
V
VDDL
– V
GNDL
=
+3.3V
V
VDDL
– V
GNDL
=
+5V
7
7
4.5
3.2
9.1
8.8
3.0
6.2
7.2
5.5
9.5
mA
11
36
36
5.5
7
14
14
V
V
V
mA
mA
mA
V
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Logic Supply Current
VDDL24F
Field Supply Voltage
VDD24F
VDD5F
Field Supply Current of VDD24F
in MAX31963
Field Supply Current of VDD24F
in MAX31953
Field Supply Current
Powered From VDD5F
I
VDD24F
I
VDD24F
I
VDD5F
When using the internal regulator in
MAX31963.
When using the internal regulator in
MAX31953
When powering the field-side directly
from a 5V supply (Note 3)
VDD24F =
24V
IN1–IN8 = 24V, LED1–
LED8 = GNDF,
CS
=
GNDL, CLK = 2MHz,
(DB0F, DB1F,
CSO,
CLKO = unconnected,
RIREF = 15kΩ.
VDD5F = 5V
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MAX31953/MAX31963
Octal Industrial Digital Input with
Isolated SPI Interface
DC Electrical Characteristics (continued)
V
VDDL
- V
GNDL
= +3.0V to +5.5V, V
VDD5F
- V
GNDF
= +4.5V to +5.5V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. C
L
= 15pF. Typical
values are at V
VDDL
- V
GNDL
= +3.3V, V
VDD5F
- V
GNDF
= +5V, VDD24F connected to VDD5F, V
GNDL
- V
GNDF
= 0V, and T
A
= +25°C.
(Note 2)
PARAMETER
VDD5F Undervoltage-Lockout
Threshold
VDD5F Undervoltage-Lockout-
Threshold Hysteresis
MAX31953 Regulator Output
Voltage
MAX31963 Regulator Output
Voltage
SYMBOL
V
UVLO5F
V
UVHYST5F
V
VDD5FL
V
VDD5FB
Max I
LOAD
=
50Ma
Max I
LOAD
=
50mA
T
A
= +25°C
T
A
= -40°C to 125°C
T
A
= +25°C
T
A
= -40°C to 125°C
4.5
4.5
4.5
4.5
CONDITIONS
VDD5F rising
MIN
3.5
TYP
4
0.4
5
5
5
5
5.5
5.5
5.5
5.5
MAX
4.5
UNITS
V
V
V
V
MAX31963 Regulator Efficiency
VDD24F = 24V, Load = 50mA
Inductor = 68µH with R = 1.95Ω,
T
A
= 25°C (e.g., inductor part number
SD3814-680R)
dVDD5F
LINEL
dVDD5F
LINEB
dVDD5F
LOAD
dVDD5F
LOAD
f
BUCK
V
ALRMOFFUV1
V
ALRMONUV1
V
ALRMOFFUV2
V
ALRMONUV2
T
ALRM
T
ALRM_HYS
TSHDN
TSHDN_HYS
I
LEDON
V
INF-
V
INF+
V
INFHYS
RIREF = 15kΩ, VDD24F =
18V to 30V
2.2kΩ external series resistor
2.2kΩ external series resistor
2.2kΩ external series resistor
6.2
I
LOAD
= 50mA, including internal load,
VDD24F = 7V to 24V
I
LOAD
= 50mA, including internal load,
VDD24F = 7V to 24V
I
LOAD
= 1mA to 50mA
C
LOAD
= 4.7µF
I
LOAD
= 5mA to 50mA
C
LOAD
= 4.7µF
VDD24F = 24V, I
LOAD
= 50mA
Rising VDD24F
Falling VDD24F
Rising VDD24F
Falling VDD24F
Junction temperature
14
7
82
%
MAX31953 Line Regulation
MAX31963 Line Regulation
MAX31953 Load Regulation
MAX31963 Load Regulation
Buck Regulator Frequency
VDD24F UV1 Alarm On/Off
VDD24F UV1 Alarm Off/On
VDD24F UV2 Alarm On/Off
VDD24F UV2 Alarm Off/On
Overtemperature Alarm
Overtemperature Alarm
Hysteresis
Thermal-Shutdown Threshold
Thermal-Shutdown Hysteresis
FIELD INPUTS
LED On-State Current
Field-Input Threshold
High-to-Low
Field-Input Threshold
Low-to-High
Field-Input Threshold Hysteresis
20
14
20
25
469
9
8
16.6
15.7
155
7
165
10
2.4
9.1
10
0.9
10.82
18
10
mV
mV
mV
mV
kHz
V
V
V
V
°C
°C
°C
°C
mA
V
V
V
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4
MAX31953/MAX31963
Octal Industrial Digital Input with
Isolated SPI Interface
DC Electrical Characteristics (continued)
V
VDDL
- V
GNDL
= +3.0V to +5.5V, V
VDD5F
- V
GNDF
= +4.5V to +5.5V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. C
L
= 15pF. Typical values
are at V
VDDL
- V
GNDL
= +3.3V, V
VDD5F
- V
GNDF
= +5V, VDD24F connected to VDD5F, V
GNDL
- V
GNDF
= 0V, and T
A
= +25°C. (Note 2)
PARAMETER
Input Threshold High-to-Low
(at IC pin)
Input Threshold Low-to-High
(at IC pin)
Input Threshold Hysteresis
(at IC pin)
Field-Input Data Rate
Current-Limit Setting Resistor
Field-Input Current Limit
SYMBOL
V
THP-
V
THP+
V
INPHYS
f
IN
RIREF
I
INLIM
Nominal value
RIREF = 15k, V
IN
= 18V to 30V,
T
A
= +25°C to +125°C (Note 4)
DB1L/DB0L = 0/0: no filtering
Debounce Filter Time Constant
(See Table 1)
t
BOUNCE
DB1L/DB0L = 0/1
DB1L/DB0L = 1/0
DB1L/DB0L = 1/1
INTERFACE LOGIC
CLK,
CS
relative to GNDL
Input Logic-High Voltage
V
IH
DB0L, DB1L relative to GNDL
DINF, MODESEL relative to GNDF
CLK,
CS
relative to GNDL
Input Logic-Low Voltage
V
IL
DB0L, DB1L relative to GNDL
DINF, MODESEL relative to GNDF
Output Logic-High Voltage
Open-Drain Pullup Current
Output Logic-Low Voltage
Logic-Input Leakage Current
Logic Input Capacitance
DYNAMIC CHARACTERISTICS
Common-Mode Transient
Immunity
dV
ISO
/dt
V
IN
= V
VDD_
or V
GND_
(Note 6)
1.5
kV/µs
V
OL
I
IL
V
OH
CLKO,
CSO
sourcing 4mA
DOUT, FAULT sourcing 4mA
DB0F, DB1F (from VDD5F)
CLKO,
CSO
sinking 4mA to GNDF
DOUT, FAULT sinking 4mA to GNDL
DB0F, DB1F sinking 4mA to GNDF
CS,
CLK
CS,
CLK (capacitance to GNDL)
-1
2
V
VDD5F
-0.4
V
VDDL
-0.4
30
0.8
0.8
0.8
1
µA
pF
V
0.7 x V
VDDL
0.80
0.7 x V
VDD5F
0.8
0.5
0.8
V
V
µA
V
V
0.008
0.25
1
4.99
2.1
IN1 – IN8
IN1 – IN8
IN1 – IN8
CONDITIONS
MIN
2.9
TYP
3.4
4.2
0.8
200
15
2.4
0
0.025
0.75
3
0.038
1.1
4.5
ms
62
2.85
4.8
MAX
UNITS
V
V
V
kHz
kΩ
mA
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