Clarity Hardware INT9 A/D CONVERTER

Significance of the Topic

The conversion of analog signals from chromatographic and electrochemical detectors into digital data is fundamental for modern laboratory and industrial analytics. High-resolution, stable and multi-channel A/D converters such as the INT9 are essential for precise peak detection, reliable quantitation and seamless integration with chromatography workstation software.

Objectives and Overview

This manual provides guidance on installing, configuring and operating the INT9 24-bit Delta-Sigma A/D converter card within the Clarity chromatography data system. It covers hardware requirements, wiring to detectors, software setup, method parameters, digital I/O control and troubleshooting.

Equipment

The INT9 is a PCI-interface card offering up to four independent, bipolar or unipolar, differential channels with user-selectable input ranges (±156 mV, ±1 250 mV, ±12 123 mV), eight TTL outputs (four also relay contacts) and four TTL inputs. It features excellent temperature stability, sigma-delta integration without data loss, and selectable mains-frequency filters (50 Hz or 60 Hz).

Methodology and Configuration

• Install Clarity software and insert the INT9 in a 32-bit PCI slot; drivers auto-install during Clarity setup.
• Connect detector signal (positive, negative, shield), start/marker inputs and digital outputs via the standard DB-37 cable or optional terminal board.
• Use the System Configuration dialog to add the INT9 module, assign channel names, set units, input ranges and sample rates (6.25 to 400 Hz at 50 Hz filter or 7.5 to 480 Hz at 60 Hz), and define digital I/O mappings.
• In Method Setup, define acquisition parameters per detector (range, sample rate) and measurement triggers (external start/stop modes, level polarity).

Performance and Discussion

Using Delta-Sigma integration, the INT9 achieves up to 21-bit noise-free resolution at low frequencies, with effective resolutions from 16 to 21 bits across its sampling range. Bipolar mode captures both positive and negative signals; unipolar mode enhances resolution by one bit. Simple software inversion corrects wiring polarity. Digital synchronization minimizes inter-channel time skews for multi-detector analyses.

Benefits and Practical Applications

• High resolution and stability improve quantitation accuracy and reproducibility.
• Multi-channel capability supports simultaneous FID, UV/VIS, electrochemical detection or pressure monitoring.
• Digital I/O control allows autosampler synchronization, event-driven valve switching and external device triggering.
• Software integration in Clarity ensures unified method development, data acquisition and processing.

Future Trends and Opportunities

Advances in A/D conversion may include higher sample rates, integrated network connectivity and cloud-based data handling. Miniaturized, low-power converters could extend real-time monitoring into remote or field applications. Enhanced software algorithms for noise suppression, baseline correction and machine-learning-based peak detection will further streamline automated workflows.

Conclusion

The INT9 A/D converter combines high-precision Delta-Sigma integration, flexible channel configuration and robust digital I/O in a single PCI card. Its seamless Clarity software integration and comprehensive support deliver reliable, multi-detector data acquisition for demanding chromatographic applications.

References

The manual does not list external literature references. Technical specifications and configuration procedures are provided by DataApex Ltd. in the INT9 user documentation.