Description

The MAX22192 is an IEC 61131-2 compliant industrialdigital input device with integrated digital isolation. TheMAX22192 translates eight, 24V current-sinking, industrialinputs to an isolated serialized SPI-compatible outputthat interfaces with 1.71V to 5.5V logic voltage. A current-settingresistor allows the MAX22192 to be configured forType 1, Type 2, or Type 3 inputs. For proximity switches,the field-wiring is verified using the wire break feature.When wire break is enabled, the active-low LFAULT output is assertedand a register flag set if the input current drops belowthe wire break threshold for more than 20ms. Additionaldiagnostics that assert active-low LFAULT include: overtemperatureprotection, low 24V field supply, 24V field supply missing,and CRC communication error.For robust operation in industrial environments, each inputincludes a programmable glitch filter. The filter delay oneach channel can be independently programmed to oneof eight values between 50µs and 20ms, or filter bypass.The MAX22192 has an isolated 4-pin SPI interface, andin addition uses isolated active-low LLATCH input for synchronizinginput data across multiple devices in parallel, and isolatedactive-low LFAULT output for instantly alerting the host of anydiagnostic issues. The digital signals with a name startingwith L are logic-side signals, and the digital signals with aname starting with F are field-side signals.The MAX22192 field-side accepts a single 7V to 65V supplyto the VDD24F pin. When powered by the field supply,the MAX22192 generates a 3.3V output on the VDD3F pinfrom an integrated LDO regulator, which can provide up to25mA of current for external loads in addition to poweringthe MAX22192. Alternatively, the MAX22192 can be poweredfrom a 3.0V to 5.5V supply connected to the VDD3Fpin. The logic-side of the MAX22192 is powered from asingle 1.71V to 5.5V supply to the VDDL pin to interfacewith 1.8V, 3.3V, or 5V logic levels.The MAX22192 has an isolation rating of 600VRMS for 60seconds and is available in a 70-pin GQFN package with2.3mm clearance and creepage. The package materialhas a minimum comparative tracking index (CTI) of 600V,which gives it a group I rating in creepage tables.ApplicationsIndustrial AutomationProcess AutomationProgrammable Logic Controllers