EVALUATION KIT AVAILABLE MAX31913 Industrial, Octal, Digital Input Translator/Serializer General Description The MAX31913 industrial interface serializer translates, conditions, and serializes the 24V digital output of sensors and switches used in industrial, process, and building automation to 5V CMOS-compatible signals required by microcontrollers. It provides the front-end interface circuit of a programmable logic controller (PLC) digital input module. The device features integrated current limiting, lowpass filtering, and channel serialization. Input current limiting allows a significant reduction in power consumed from the field voltage supply as compared to traditional discrete resistor-divider implementations. Selectable onchip lowpass filters allow flexible debouncing and filtering of sensor outputs based on the application. On-chip serialization allows a drastic reduction in the number of optocouplers used for isolation. The device serializer is stackable so that any number of input channels can be serialized and output through only one SPI-compatible port. This reduces the number of optocouplers needed to only three, regardless of the number of input channels. For enhanced robustness with respect to high-frequency noise and fast electrical transients, a multibit CRC code is generated and transmitted through the SPI port for each 8 bits of data. The on-chip 5V voltage regulator can be used to power external optocouplers, digital isolators, or other external 5V circuitry. Field-side LED drivers recycle the current from the eight inputs to provide visual input status indication without any additional current or power consumption. For ultra-low-power applications, and for the lowest possible heat dissipation. Maxim Integrated plans to offer a pin-compatible version of this device, the MAX31912. The MAX31912 uses patent-pending circuit techniques to achieve further reduction of power beyond what is possible by input current limiting alone. Contact the factory for availability. Features S Eight High-Voltage Input Channels (36V max) S Configurable for IEC 61131-2 Input Types 1, 2, 3 S Wide Operating Supply Range of 7V to 36V S Optional Configuration Allows 5V Supply S Selectable Input Filtering and Debouncing from 0ms to 3ms S Configurable Input Current Limiting from 0.5mA to 6mA S High HBM ESD Immunity on All Field Input Pins S On-Chip 8-to-1 Serialization with SPI Interface S On-Chip 5V Regulator S Overtemperature Indicator S On-Chip 24V Field Supply Voltage Monitor S Very Low Quiescent Current and Power/Heat Dissipation S Multibit CRC Code Generation and Transmission for Error Detection and More Reliable Data Transmission to an External Micro S Field-Side Energyless LED Drivers Applications Digital Input Modules for PLCs Industrial, Building, and Process Automation Motor Control Block Diagram 24V VCC24V 5VOUT 5V REGULATOR SUPPLY MONITOR VREF FAULTB TEMP MONITOR RIREF RT0 DB0 DB1 CRC GEN. CURRENT LIMITER IN0 LP FILTER SENSORS Ordering Information appears at end of data sheet. VREF RT7 SIN µCONTROLLER OR ISOLATION MODESEL VOLTAGE COMPARATOR CLK INPUT CHANNEL 0 IN7 GND 5V MAX31913 SERIALIZER INPUT CHANNEL 7 CS SOUT For related parts and recommended products to use with this part, refer to www.maximintegrated.com/MAX31913.related. For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com. 19-6641; Rev 0; 3/13 MAX31913 Industrial, Octal, Digital Input Translator/Serializer ABSOLUTE MAXIMUM RATINGS (Voltages relative to GND.) Voltage Range on VCC24V.............................. -0.3V to +45V Voltage Range on IN1–IN8............................. -0.3V to +45V Voltage Range on IN1–IN8 (through 2.2kω resistors).............................. -45V to +45V Voltage Range on DB0/DB1, CLK, SIN, CS, MODESEL........................... -0.3V to (V5VOUT + 0.3V) Continuous Power Dissipation (TA = +70NC) TSSOP (derate 27mW/NC above +70NC)........... 2162.2mW Operating Temperature Range Ambient Temperature............................... -40NC to +125NC Junction Temperature.............................. -40NC to +150NC Storage Temperature Range....................... -55NC to +125NC Lead Temperature (soldering, 10s)..........................+300NC Soldering Temperature (reflow)................................+260NC 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 (qJA)...........37°C/W Junction-to-Case Thermal Resistance (qJC)..................2°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. RECOMMENDED OPERATING CONDITIONS (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Field Supply Voltage VCC24V (Note 3) 7 36 V Field Inputs Voltage VINn (Note 4) -0.3 36 V Logic Inputs Voltage VLOGIC Current-Limit Setting Resistor Field Input Data Rate Maxim Integrated 0 RREF fIN (Note 5) 5.5 V 15 kI 200 kHz 2 MAX31913 Industrial, Octal, Digital Input Translator/Serializer DC ELECTRICAL CHARACTERISTICS (VCC24V = 7V to 36V, TJ = -40NC to +150NC, unless otherwise noted.) (Note 2) PARAMETER Field-Supply Current SYMBOL CONDITIONS ICC24V IN1–IN8 = 24V, 5VOUT = open, RT1–RT8 = GND, all logic inputs open Field-Supply UV1 Alarm Off/On VONUV1 Field-Supply UV1 Alarm On/Off VOFFUV1 Field-Supply UV2 Alarm Off/On VONUV2 Field-Supply UV2 Alarm On/Off VOFFUV2 LED On-State Current IRT-ON MIN 7 TYP MAX UNITS 1.6 2.3 mA 9 10 V 8 16.5 14 RREF = 15kI, VCC24V = 18V to 30V V 18 V 15.5 V 2.2 mA 8.4 V Field Input Threshold High-toLow VIN-(INF) 2.2kI external series resistor Field Input Threshold Low-toHigh VIN+(INF) 2.2kI external series resistor 9.4 Field Input Hysteresis VHYS(INF) 2.2kI external series resistor 1 V Input Threshold High-to-Low (at IC pin) VTH-(INP) 3.4 V Input Threshold Low-to-High (at IC pin) VTH+(INP) 4.4 Input Threshold Hysteresis (at IC pin) VHYS(INP) 1 V Field Input Pin Resistance RINP 0.8 kI Field Input Current Limit Filter Time Constant Linear Regulator Output 7 3 IINLIM RREF = 15kI, VCC24V = 18V to 30V, TA = +25°C to +125°C (Note 6) 10.2 5 2.2 2.4 2.7 tFILTER DB1/DB0 = 0/0: no filtering DB1/DB0 = 0/1 DB1/DB0 = 1/0 DB1/DB0 = 1/1 0.008 0.25 1.0 0 0.025 0.75 3 0.038 1.1 4.5 V5VOUT Max ILOAD = 50mA 4.75 V V mA ms 5.0 5.25 V Regulator Line Regulation dVREGLINE ILOAD = 50mA 10 20 mV Regulator Load Regulation dVREGLOAD ILOAD = 1mA to 50mA 20 50 mV 0.4 1.0 V Logic-Low Output Voltage VOL IOL = 4mA Logic-High Output Voltage VOH IOH = -4mA Logic-Input Trip Point VIH-IL 0.3 x V5VOUT 0.5 x V5VOUT 0.7 x V5VOUT V IIL -50 -30 -15 FA Logic-Input Leakage Current Overtemperature Alarm Maxim Integrated TALRM 4.0 V 135 NC 3 MAX31913 Industrial, Octal, Digital Input Translator/Serializer AC ELECTRICAL CHARACTERISTICS (VCC24V = 7V to 36V, TJ = -40NC to +150NC, unless otherwise noted.) (Note 2) PARAMETER Field Input Pulse Width SYMBOL tPW ESD CONDITIONS No external capacitors on pins IN1-IN8 MIN TYP MAX UNITS µs 1 HBM, all pins ±2 HBM, IN1-IN8 with respect to GND ±15 kV AC ELECTRICAL CHARACTERISTICS: SPI INTERFACE (VCC24V = 7V to 36V, TJ = -40NC to +150NC, unless otherwise noted.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS CLK Pulse Duration tCLKPW (Note 7) 20 ns CS Pulse Duration tCSPW (Note 8) 20 ns tSU1 (Note 9) 5 ns SIN to CLK Hold Time tH1 (Note 9) 8 ns CS to CLK Setup Time tSU2 (Note 10) 8 ns CS to CLK Recovery Time tREC (Note 10) 12 Clock Pulse Frequency fCLK (Notes 7, 11) 25 MHz tP1 (Note 7) 20 ns Propagation Delay, CS to SOUT tP2 (Note 8) 20 ns Rise/Fall Time SOUT/FAULT tR/F (Note 7) 40 ns SIN to CLK Setup Time Propagation Delay, CLK to SOUT ns Limits are 100% production tested at TA = +25°C and/or TA = +125°C. Limits over the operating temperature range and relevant supply voltage range are guaranteed by design and characterization. Typical values are not guaranteed. 3: If a 24V supply is not available, the device can be powered through V5VOUT. In this mode of operation, the VCC24V supply must be left unconnected. All other specifications remain identical. The field-supply UV1 and UV2 alarms will be activated (set to 1), indicating the absence of the 24V supply in this mode of operation. 4: When using suggested external 2.2kω series resistors, limits of -3V to +36V apply. 5:fIN refers to the maximum pulse frequency (1/fIN = shortest pulse width) that can be detected from the field sensors and switches. 6: External resistor RREF can be adjusted to set any desired current limit between 0.5mA and 6mA. 7:See Figure 8. 8:See Figure 5. 9:See Figure 7. 10:See Figure 6. 11: This is the maximum bit transfer rate through the serializer interface. Note 2: Note Note Note Note Note Note Note Note Note Maxim Integrated 4 MAX31913 Industrial, Octal, Digital Input Translator/Serializer Typical Operating Characteristics (TA = +25°C, RREF = 15kω, unless otherwise noted.) SUPPLY CURRENT vs. VCC24V FIELD SUPPLY 1.75 1.70 1.65 1.60 2.1 2.0 1.9 1.8 5.5 1.7 4.5 3.5 2.5 1.5 1.6 1.55 5 15 25 0.5 1.5 35 -40 10 60 0 110 50 40 CURRENT LIMIT vs. FIELD-INPUT VOLTAGE INPUT-VOLTAGE HYSTERESIS vs. TEMPERATURE 2.4 2.3 2.2 1.5 1.0 0.5 2.1 -40 10 60 5 110 INPUT-VOLTAGE HYSTERESIS vs. TEMPERATURE 15 25 ON-OFF THRESHOLD 7.6 TEMPERATURE (°C) Maxim Integrated 3.2 ON-OFF THRESHOLD 3.0 -40 10 110 60 110 TEMPERATURE (°C) LDO LINE REGULATION 5.10 MAX31913 toc08 5.08 5.06 5.02 5.00 4.98 4.96 I5VOUT = 5mA 5.08 5.06 5VOUT VOLTAGE (V) 5.04 5.04 5.02 5.00 4.98 4.96 4.94 4.94 4.92 4.92 4.90 4.90 60 3.6 3.4 LDO LOAD REGULATION 5VOUT VOLTAGE (V) OFF-ON THRESHOLD 8.8 10 3.8 35 5.10 MAX31913 toc07 RIN = 2.2I 9.6 9.4 -40 OFF-ON THRESHOLD 4.0 FIELD-INPUT VOLTAGE (V) TEMPERATURE (°C) 9.2 9.0 4.6 4.4 4.2 2.8 2.6 0 2.0 RIN = 0I MAX31913 toc09 2.5 2.0 5.0 4.8 INPUT-VOLTAGE HYSTERESIS (V) 2.5 CURRENT LIMIT (mA) 2.6 MAX31913 toc05 MAX31913 toc04 3.0 MAX31913 toc06 CURRENT LIMIT vs. TEMPERATURE 2.7 8.0 7.8 30 RREF (kI) 2.8 8.6 8.4 8.2 20 TEMPERATURE (°C) 2.9 10.0 9.8 10 SUPPLY VOLTAGE (V) 3.0 INPUT-VOLTAGE HYSTERESIS MAX31913 toc03 2.2 CURRENT LIMIT (mA) 1.80 MAX31913 toc02 MAX31913 toc01 2.3 SUPPLY CURRENT (mA) SUPPLY CURRENT (mA) 1.85 CURRENT LIMIT (mA) CURRENT LIMIT vs. RREF SUPPLY CURRENT vs. TEMPERATURE 1.90 0 10 20 30 40 5VOUT OTPUT CURRENT (mA) 50 6 11 16 21 26 31 36 SUPPLY VOLTAGE (V) 5 MAX31913 Industrial, Octal, Digital Input Translator/Serializer Typical Operating Characteristics (continued) (TA = +25°C, RREF = 15kω, unless otherwise noted.) LDO OUTPUT vs. VCC24V FIELD SUPPLY LDO LINE REGULATION 5.04 5.02 5.00 4.98 4.96 5.2 5.1 5.0 4.9 4.8 4.7 4.92 4.6 4.5 6 11 16 21 26 31 14 24 SUPPLY VOLTAGE (V) SUPPLY VOLTAGE (V) LDO OUTPUT VOLTAGE vs. TEMPERATURE LDO OUTPUT VOLTAGE vs. TEMPERATURE 5.06 5.02 5.00 4.98 4.96 5.06 5.04 5.02 5.00 4.98 4.96 4.94 4.94 4.92 4.92 4.90 I5VOUT = 5mA 5.08 5VOUT VOLTAGE (V) 5.04 34 5.10 MAX31913 toc12 I5VOUT = 0mA 5.08 4 36 5.10 5VOUT VOLTAGE (V) 5.3 4.94 4.90 4.90 -40 10 60 AMBIENT TEMPERATURE (°C) Maxim Integrated I5VOUT = 50mA 5.4 MAX31913 toc13 5VOUT VOLTAGE (V) 5.06 5.5 MAX31913 toc11 I5VOUT = 50mA 5.08 5VOUT OTPUT VOLTAGE (V) MAX31913 toc10 5.10 110 -40 10 60 110 AMBIENT TEMPERATURE (°C) 6 MAX31913 Industrial, Octal, Digital Input Translator/Serializer Pin Configuration TOP VIEW + DB0 1 28 GND DB1 2 27 SIN IN1 3 26 MODESEL RT1 4 25 CLK IN2 5 24 CS RT2 6 23 SOUT IN3 7 22 IN8 RT3 8 21 RT8 IN4 9 20 IN7 RT4 10 19 RT7 IN5 11 18 IN6 RT5 12 17 RT6 RIREF 13 16 FAULT VCC24V 14 15 5VOUT MAX31913 EP Pin Description PIN NAME 1, 2 DB0, DB1 3, 5, 7, 9, 11, 18, 20, 22 IN1–IN8 Field Inputs 4, 6, 8, 10, 12, 17, 19, 21 RT1–RT8 Energyless LED Driver Outputs. Connect to GND if LEDs are not required. 13 RIREF 14 VCC24V Field-Supply Voltage 15 5VOUT 5V Regulator Output 16 FAULT Active-Low Undervoltage Alarm 23 SOUT Serial-Data Out 24 CS 25 CLK 26 MODESEL 27 SIN 28 GND — EP Maxim Integrated FUNCTION Debounce (Filtering) Time Select Inputs Current-Limiter Reference Resistor Active-Low Chip-Select Input Serial-Clock Input Mode-Select Input MODESEL = 1: Selects 8-bit shift register MODESEL = 0: Selects 16-bit shift register Serial-Data Input Field Ground Exposed Pad. Must be connected to the PCB ground plane. 7 MAX31913 Industrial, Octal, Digital Input Translator/Serializer Typical Application Circuit JUMPERS TO 5VOUT AND GND R1 24V 5VOUT VCC24V C1 DB0 DB1 C3 VDD_LOGIC MODESEL SIN RINX fIN1–8 MAX31913 CLK IN1–8 CLK CS CS ISOLATION RT1–8 LED 1–8 SOUT SOUT FAULT FAULT GND RIREF RREF Detailed Description Input Current Clamp The MAX31913 industrial interface serializer inputs (IN1–IN8) sense the state (on vs. off) of field sensors by monitoring both voltage and current flowing through the sensor output. The current sinking through these input pins rises linearly with input voltage until the limit set by the current clamp is reached. Any voltage increase beyond this point does not increase the input current any further. The value of the current clamp is adjustable through an external resistor connected between the RIREF pin and GND. Pins RT0–RT7 must be connected directly to GND to provide a return path for the input current. The voltage and current at the IN1–IN8 input pins are compared against internally set references to deter- Maxim Integrated mine whether the 0). The trip points sensor satisfy the 1 and 3 switches. to work as a Type sensor is on (logic 1) or off (logic determining the on/off status of the requirements of IEC 61131-2 Type The device can also be configured 2 switch. Glitch Filter A digital glitch filter provides debouncing and filtering of noisy sensor signals. The time constant of this filter is programmable from 0ms to 3ms through the DB0 and DB1 pins. See Table 1 for debounce settings. To provide the digital glitch filter, the device checks that an input is stable for at least three clock cycles. The duration of a clock cycle is 1/3 of the selected debounce time. If the input is not stable for at least three clock cycles, the input change is not sent to the internal shift register. 8 MAX31913 Industrial, Octal, Digital Input Translator/Serializer Reading Serial Data The filtered outputs of the input comparators are latched into a shift register at the falling edge of CS. Clocking the CLK pin, while CS is held low, shifts the latched data out of SOUT 1 bit at a time. The internal data serializer comprises a 16-bit shift register, containing 8 bits of data corresponding to the eight field inputs, as well as an 8-bit status byte containing supplementary status and CRC information. The status byte contains 1 bit representing the status of the field-supply voltage (UV), 1 bit representing the status of the internal temperature monitor (OT), a 5-bit CRC code internally calculated and generated, and a trailing 1 as a STOP bit. The undervoltage (UV) bit is normally 0. If the supply voltage falls below VOFFUVLO, the UV becomes a 1. The UV bit returns to 0 once the supply voltage has returned above VONUVLO. The overtemperature (OT) bit is also normally 0. If the junction temperature increases to above TALRM, the OT bit becomes a 1. The bit returns to 0 once the junction temperature has returned below TALRM. The CRC code can be used to check data integrity during transfer from the device to an external microcontroller. In applications where the integrity of data transferred is not of concern, the CRC bits can be ignored. The CRC uses the following polynomial: P(x) = x5 + x4 + x2 + x0 The number of bits in the internal serializer can be selected between 8 bits or 16 bits. The MODESEL pin is used to configure the serializer as an 8-bit (disabling the status byte) or 16-bit shift register. In 8-bit mode, only the eight field input states are transferred through the SPI port and the status byte is ignored. Therefore, in multiple IC applications (input channels greater than 8), if desired, only a single status byte can be generated and transmitted for any number of input channels. The shift register contents are read only (no write capability exists) through the SPI-compatible interface. For higher input counts than 8, multiple devices can be cascaded. In this case, the SOUT pin of one device should be connected to the SIN pin of the next device, effectively cascading the internal shift registers. The CLK and CS pins of all the devices should be connected together in this configuration. See the Serial-Port Operation section for more detailed information on operating the SPI interface. Temperature Monitoring The internal junction temperature of the device is constantly monitored. An alarm is raised, by asserting the OT bit to a 1. Supply Voltage Monitoring A primary supply voltage monitor circuit constantly monitors the field-supply voltage. If this voltage falls below a threshold (VOFFUV1), an alarm is raised by asserting the FAULT pin, indicating that the part is experiencing a fault condition and the data in the serializer is not to be trusted. In addition, the device resets the UV1 bit to a 0. Once the field-supply voltage has recovered and goes above VONUV1, the FAULT pin is released. A secondary supply voltage monitor circuit also monitors the field-supply voltage. This secondary monitor only raises a flag in the serializer, by resetting the UV2 bit to 0 (it does not assert the FAULT pin), if the field supply drops below VOFFUV2. Once the supply voltage goes back above VONUV2, the UV2 bit is set to 1. The secondary supply monitor has higher trip points and its purpose is to warn the system that the supply voltage is below specifications (approximately 24V - 20%). Whereas the purpose of the primary supply monitor is to warn that the supply voltage has dropped to a value close to the minimum operating voltage of the IC. Table 1. Debounce Settings DB1 DB0 BINARY VALUE DEBOUNCE TIME 0 0 0 0 0 1 1 25Fs 1 0 2 0.75ms 1 1 3 3ms Maxim Integrated 9 MAX31913 Industrial, Octal, Digital Input Translator/Serializer Applications Information system to meet or exceed international EMC requirements. Table 2 lists an example device for each component in Figure 1. The system shown in Figure 1, using the components shown in Table 2, is designed to be robust against IEC burst transient, surge transient, and RFI specifications (IEC 61000-4, -5, -6, and -2). EMC Standards Compliance The external components shown in Figure 1 allow the device to operate in harsh industrial environments. Components were chosen to assist in suppression of voltage burst and surge transients, allowing the Table 2. Recommended Components COMPONENT DESCRIPTION REQUIRED/RECOMMENDED/OPTIONAL C0 4.7nF, 2kV polypropylene capacitor C1 10FF, 60V ceramic capacitor Required C3 100nF, 10V ceramic capacitor Recommended C4 4.7µF, 10V low ESR ceramic capacitor D0 36V fast zener diode (ZSMB36) D1 General-purpose rectifier (IN4007) LED1–LED8 Recommended Required Recommended Optional: For reverse polarity protection LEDs for visual input status indication Optional R1 150I, 1/3W MELF resistor Required RINX 2.2kI, 1/4W MELF resistor Required RREF 15kI, 1/8W resistor Required 24V JUMPERS TO 5VOUT AND GND R1 5VOUT VCC24V C0 D0 C1 DB0 DB1 C3 C4 VDD_LOGIC MODESEL SIN MAX31913 RINX fIN1–8 CLK IN1–8 CLK CS CS ISOLATION RT1–8 LED 1–8* RIREF SOUT SOUT FAULT FAULT GND RREF D1 0V C0 *IF LEDS ARE NOT USED, USER MUST GROUND THE RT PINS. Figure 1. Typical EMC Protection Circuitry Maxim Integrated 10 MAX31913 Industrial, Octal, Digital Input Translator/Serializer Serial-Port Operation Serial output of the device functions in one of two modes, depending on the MODESEL setting (Table 3). With MODESEL = 0, the device output includes a 5-bit CRC, an undervoltage alarm, and an overtemperature alarm. See the Detailed Description for CRC, undervoltage, and overtemperature functional descriptions. With MODESEL = 1, the device outputs only the state of the IN1–IN8 inputs and omits the CRC, undervoltage alarm, and overtemperature alarm. Daisy-Chain Operation For systems with more than eight sensor inputs, multiple devices can be daisy-chained to allow access to all data inputs through a single serial port. When using a daisychain configuration, connect SOUT of one of the devices to the SIN input of another upstream device. CS and SCK of all devices in the chain should be connected together SIN SIN MAX31913 SOUT in parallel (see Figure 2). In a daisy-chain configuration, external components used to enhance EMC robustness do not need to be duplicated for each device of a circuit board. Figure 3 illustrates a 16-input application. SPI Waveforms The serial output of the device adheres to the SPI protocol, running with CPHA = 0 and CPOL = 0. Input states on IN1–IN8 are latched in on the falling edge of CS. The transfer of data out of the slave output, SOUT, starts immediately when CS is asserted (i.e., MSB is output onto SOUT independent of CLK). The remaining data bits are shifted out on the falling edge of CLK. The data bits are written to the output SOUT with MSB first. When CS is high, SOUT is high impedance. The resultant timing is shown in Figure 4. Note that all bits after IN1 are invalid if 8-bit operation mode is selected with the MODESEL input. Figure 5, Figure 6, Figure 7, and Figure 8 illustrate SPI timing specifications. SIN MAX31913 SOUT MAX31913 SOUT TO µCONTROLLER Figure 2. Daisy-Chain Operation Table 3. MODESEL Settings MODESEL SETTING FUNCTIONALITY 0 16-bit output; [IN8–IN1][CRC (5 bit)][UV1][OT][UV2] 1 8-bit output; [IN8–IN1] Maxim Integrated 11 MAX31913 Industrial, Octal, Digital Input Translator/Serializer 24V JUMPERS TO 5VOUT AND GND R1 5VOUT VCC24V C0 D0 C1 DB0 DB1 C3 C4 MODESEL VDD_LOGIC MAX31913 SIN RINX fIN1–8 CLK IN1–8 CLK CS CS ISOLATION RT1–8 RIREF SOUT SOUT FAULT FAULT GND RREF D1 0V C0 CLK VCC24V CS C1 SOUT FAULT SIN RINX fIN1–8 MAX31913 IN1–8 JUMPERS TO 5VOUT AND GND 5VOUT DB0 DB1 RT1–8 MODESEL RIREF GND C3 C4 RREF Figure 3. 16-Input Application Circuit Maxim Integrated 12 MAX31913 Industrial, Octal, Digital Input Translator/Serializer CLK SOUT IN8 IN7 IN6 IN5 IN4 IN3 IN2 IN1 CRC4 CRC3 CRC2 CRC1 CRC0 UV OT RES CS IN8 –IN0 VALID Figure 4. SPI Communication Example tCSPW tP2 tSU1 CS tH1 CLK SIN VALID SIN SOUT Figure 5. SPI Timing Diagram 1 Figure 7. SPI Timing Diagram 3 1/fCLK tSU2 tCLKPW tREC CLK CS tR/F CLK SOUT tP1 tR/F Figure 6. SPI Timing Diagram 2 Maxim Integrated Figure 8. SPI Timing Diagram 4 13 MAX31913 Industrial, Octal, Digital Input Translator/Serializer Package Information Chip Information PROCESS: S45JRS Ordering Information PART TEMP RANGE PINPACKAGE MAX31913AUI+ -40NC to +125NC 28 TSSOP Bulk 28 TSSOP Tape and Reel MAX31913AUI+T -40NC to +125NC CARRIER For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 28 TSSOP-EP U28E+4 21-0108 90-0146 +Denotes a lead(Pb)-free/RoHS-compliant package. T = Tape and reel. Maxim Integrated 14 MAX31913 Industrial, Octal, Digital Input Translator/Serializer Revision History REVISION NUMBER REVISION DATE 0 3/13 DESCRIPTION Initial release PAGES CHANGED — Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. Maxim Integrated 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-1000 © 2013 Maxim Integrated Products, Inc. 15 Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.