Analog Devices Inc. DC344A

Overview

DC344A is a demonstration board from Analog Devices (formerly Linear Technology) built around the LTC2420 - a 20-bit delta-sigma analog-to-digital converter with ±4 ppm INL, 1.2 ppm RMS noise, and integrated 50/60 Hz line rejection. It operates from a single 2.7–5.5 V supply, draws <250 µA, and interfaces via SPI/Microwire to a PC's serial port for real-time data acquisition and analysis.

For engineers reviewing the DC344A datasheet, DC344A pinout, DC344A application, or DC344A equivalent, this board enables rapid validation of high-accuracy ADC performance in sensor signal chains, precision instrumentation, and low-power industrial monitoring systems where ratiometric measurement, ground-referenced input flexibility, and software-controllable fast mode (100 sps) are critical.

Technical Context

The DC344A implements the LTC2420 in a fixed SO-8 configuration with on-board LTC1460 5 V reference, enabling a –0.3 V to +5.3 V analog input range. Its internal oscillator supports configurable 50/60 Hz or 800 Hz noise rejection via jumper JP1 and JP3-controlled fast-mode activation.

Serial communication uses standard RS-232-level signals translated to TTL logic, with real-time software visualization of noise histograms, transient output, and RMS noise in ppm - all derived directly from unaveraged single-shot conversions without firmware averaging.

Key Specifications

Availability

DC344A is available at Aetrix Electronics and suitable for precision sensor interfacing, portable instrumentation calibration, and industrial process monitoring requiring stable component supply, traceable sourcing, and long-term evaluation platform continuity.

Supply support for DC344A includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices designs high-performance analog, mixed-signal, and digital signal processing ICs for precision measurement, power management, and RF applications.

The DC344A belongs to Analog Devices' demonstration board portfolio for delta-sigma ADCs, developed to accelerate evaluation of ultra-low-noise, high-accuracy converters like the LTC2420 in real-world signal chain environments.

FAQ

Does the DC344A require an external power supply?

No, the DC344A derives all operating power from the host PC's RS-232 serial port - no external supply or batteries are needed. The LTC2420 itself operates from a regulated 5 V rail generated on-board by the LT1460, and total current draw remains under 250 µA. This makes DC344A ideal for field-deployable or lab-bench evaluation without auxiliary power infrastructure.

What is the role of jumper JP1 on the DC344A?

Jumper JP1 configures the LTC2420's internal oscillator for 50 Hz or 60 Hz line frequency rejection - tied to V_CC for 60 Hz (default), or grounded for 50 Hz. This setting determines the fundamental notch frequency used during normal conversion mode and directly affects AC noise suppression in mains-powered environments where the DC344A is deployed.

Can I use an external voltage reference with the DC344A?

Yes, the DC344A supports external references from 0.1 V to 5 V via banana connector J1. When JP1 is opened, the on-board LTC1460 is disconnected, allowing user-supplied reference signals. The reference output (J2) remains available for ratiometric measurements regardless of source, preserving measurement integrity when scaling with sensor excitation or bridge outputs.

How does Fast Mode affect the DC344A's performance?

In Fast Mode, the DC344A drives the LTC2420's F0 pin with a 2.048 MHz oscillator (enabled by removing JP3), raising output rate to 100 sps with 16-bit effective noise and 12-bit total unadjusted error. This mode trades ultimate DC accuracy for speed while retaining real-time histogram and transient visualization - useful for dynamic signal observation and comparative testing against normal 50/60 Hz rejection mode.

Is the DC344A compatible with modern Windows operating systems?

The original DC344A software targets Windows 95/98 and requires legacy RS-232 COM port access. While it may function under Windows 10/11 via USB-to-serial adapters and compatibility mode, official driver support is discontinued. Users should verify serial port enumeration and permissions; alternative evaluation requires custom host software using the documented SPI timing and command protocol of the LTC2420 on the DC344A.