MAX31913 Industrial, Octal, Digital Input Translator/Serializer General Description Benefits and Features The MAX31913 industrial interface serializer translates, Very Low Power and Heat Dissipation Low Quiescent Current (1.6mA typ) conditions, and serializes the 24V digital output of sensors and switches used in industrial, process, and building Highly Accurate and Stable Input Current Limiters, Adjustable from 0.5mA to 6mA automation to 5V CMOS-compatible signals required Energy-Less Field-Side LED Drivers by microcontrollers. It provides the front-end interface circuit of a programmable logic controller (PLC) digital High Integration Reduces BOM Count, Board Size, input module. and System Cost 8 High-Voltage Input Channels (36V max) The device features integrated current limiting, lowpass On-Chip 8-1 Serialization with SPI Interface filtering, and channel serialization. Input current limiting On-Chip 5V Regulator allows a significant reduction in power consumed from On-Chip Overtemperature Indicator the field voltage supply as compared to traditional Dual On-Chip Field Supply Voltage Monitor discrete resistor-divider implementations. Selectable on- Integrated Debounce Filters, Selectable From 0 to 3ms chip lowpass filters allow flexible debouncing and filter- Robust Features and Performance for Industrial ing of sensor outputs based on the application. Environments On-chip serialization allows a drastic reduction in the Multibit CRC Code Generation and Transmission for number of optocouplers used for isolation. The device Error Detection and More Reliable Data Transmission serializer is stackable so that any number of input channels High ESD Immunity on All Field Input Pins can be serialized and output through only one SPI- Accepts Industry Standard Input Types compatible port. This reduces the number of optocou- Configurable for IEC 61131-2 Input Types 1, 2, and 3 plers needed to only three, regardless of the number of Flexible Power Supply Capability Enables Usage input channels. in 5V, 12V, 24V, and Higher Voltage Systems For enhanced robustness with respect to high-frequency Wide Operating Field Supply Range of 7V to 36V noise and fast electrical transients, a multibit CRC code Can Be Powered From the Logic-Side Using a 5V is generated and transmitted through the SPI port for Supply each 8 bits of data. The on-chip 5V voltage regulator Applications can be used to power external optocouplers, digital isola- tors, or other external 5V circuitry. Field-side LED drivers Digital Input Modules for PLCs Industrial, Building, and Process Automation recycle the current from the eight inputs to provide visual input status indication without any additional current or Motor Control power consumption. For ultra-low-power applications, and for the lowest possible heat dissipation, Maxim Integrated offers 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. Ordering Information appears at end of data sheet. 19-6641 Rev 3 4/15MAX31913 Industrial, Octal, Digital Input Translator/Serializer Block Diagram 24V 5V 5VOUT V 5V REGULATOR CC24V MAX31913 VREF SUPPLY FAULTB MONITOR TEMP MONITOR DB0 DB1 RIREF CRC GEN. CURRENT RT1 LIMITER IN1 CONTROLLER LP SENSORS SIN OR FILTER ISOLATION MODESEL VOLTAGE COMPARATOR VREF CLK SERIALIZER CS INPUT CHANNEL 0 RT8 SOUT INPUT CHANNEL 7 IN8 GND Maxim Integrated 2 www.maximintegrated.com