Acromag IP440A-2 Isolated Digital Input Module

The Acromag IP440A-2 is a 32-channel isolated digital input module engineered for industrial monitoring applications requiring high noise immunity and signal integrity. Each of the 32 optically isolated input channels safeguards connected systems from transient signals and ground loops. Four distinct 8-channel ports provide individual isolation from logic circuitry and from each other, enabling reliable discrete signal acquisition in electrically challenging environments.

Technical Specifications

• 32 optically isolated channels


• Input voltage range: ±16V to ±40V DC or AC peak


• Input low-to-high threshold: ±6.8V typical


• Response time: 10µS (off to on), 15µS (on to off)


• Selectable debounce: 4µS, 64µS, 1mS, or 8mS (±250nS error margin)


• Input hysteresis for improved noise immunity


• Reverse polarity protection


• Change-of-state interrupts with programmable polarity Isolation & Voltage Withstand


• Logic and field connections optically isolated


• Individual port isolation from each other


• Continuous isolation rating: 250V AC rms and 250V DC


• Dielectric strength: 1500V AC for one minute Data Transfer & Processing


• Access time: 250ns per cycle at 8MHz clock


• Support for IOSel*, IDSel*, and INTSel* cycle types


• Four 8-bit reads required to update all 32 channels


• Zero wait states


• Software configuration allows on-the-fly parameter changes


• Initial configuration time: up to 200mS after power-up Physical


• Dimensions: 4 × 2 × 1 inches


• Weight: 8 oz


• Field I/O: 50-pin female receptacle header (AMP 173279-3 or equivalent)


• Logic interface: 50-pin female receptacle header


• M2 threaded screws and spacers supplied Environmental


• Operating temperature: 0°C to 70°C (extended range -40°C to 85°C available)


• Storage temperature: -55°C to 150°C


• Relative humidity: 5% to 95% non-condensing

Key Features

• Optoelectronic isolation eliminates ground loop coupling


• Debounce selectivity from 4µS to 8mS accommodates various signal types


• Programmable interrupt generation on state transitions


• No jumpers or switches required; full software configuration


• Threaded connector hardware enhances mechanical stability

Typical Applications Industrial control systems, SCADA networks, process monitoring, discrete signal acquisition in noisy environments, safety interlocks, and condition-based maintenance systems.

Compatibility & Integration The module connects to industrial I/O backplanes via standard 50-pin female receptacle headers. Software configuration through IOSel*, IDSel*, and INTSel* cycle types enables integration into custom measurement and control systems without hardware modification.