Analog Devices Inc. DC273A

Overview

DC273A from Analog Devices (formerly Linear Technology) is an evaluation board for the LTC2404/LTC2408 4-/8-channel, 24-bit micropower delta-sigma ADCs. It enables rapid validation of high-precision, low-latency analog-to-digital conversion in multiplexed sensor systems operating from 2.7V to 5.5V supply, with integrated 50Hz/60Hz notch filtering and extended input range (–12.5% to +112.5% VREF). It supports direct connection to strain gauges, thermocouples, and precision transducers.

For engineers reviewing the DC273A datasheet, DC273A pinout, DC273A application, or DC273A equivalent, this page delivers verified hardware interface details, real-world timing behavior, supported reference configurations (0.1V to VCC), noise performance (0.3ppm RMS), and multiplexer control logic - all essential for industrial data acquisition, weigh scale design, and high-stability instrumentation prototyping.

Technical Context

The DC273A implements the full signal chain for the LTC2404/LTC2408, including precision external reference buffering, configurable channel selection via on-board jumpers or SPI, and selectable internal/external oscillator modes for 50Hz or 60Hz ±2% rejection. Its layout maintains strict analog/digital ground separation and uses low-ESR ceramic/tantalum decoupling per pin.

It exposes all 28-pin SSOP signals-including MUXOUT, FO, CSMUX, DIN, CLK, SCK, and SDO-via test points and headers, enabling direct oscilloscope probing of conversion timing (tCONV = 130.7–163.2 ms), digital interface waveforms, and EOC assertion. The board operates across the full –40°C to 85°C temperature range when paired with LTC2404I/LTC2408I devices.

Key Specifications

Availability

DC273A is available at Aetrix Electronics and suitable for industrial process control, precision weigh scales, gas analyzers, and strain gauge transducer systems requiring stable component supply and validated reference designs for high-resolution ADC integration.

Supply support for DC273A 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, Inc. (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors.

The DC273A belongs to Analog Devices' evaluation board portfolio for precision data converters, designed specifically to accelerate development of low-noise, low-power, high-accuracy measurement systems in industrial, scientific, and medical instrumentation.

FAQ

What is the primary function of the DC273A evaluation board?

The DC273A evaluation board is a fully assembled and tested platform for evaluating the LTC2404 and LTC2408 24-bit micropower delta-sigma ADCs. It provides immediate access to all device pins, pre-configured reference sources, and jumper-selectable operating modes (e.g., 50Hz vs 60Hz notch), enabling engineers to validate signal integrity, timing, noise, and multiplexer behavior without custom PCB design. DC273A directly supports DC273A's target use cases in high-precision sensor digitization.

Does DC273A support both LTC2404 and LTC2408 devices?

Yes, DC273A supports both the LTC2404 (4-channel) and LTC2408 (8-channel) in identical 28-lead SSOP packages. The board accommodates either device using the same footprint and pin mapping; unused CH4–CH7 pins are left unconnected when using the LTC2404. All functional blocks-including MUX control, reference routing, and digital interface-operate identically for both parts. DC273A's design ensures full compatibility with both variants.

How does DC273A implement 50Hz/60Hz line rejection?

DC273A implements 50Hz/60Hz line rejection by routing the FO (Filter Oscillator) pin to either VCC (for 50Hz rejection) or GND (for 60Hz rejection) via on-board solder jumpers. This configures the LTC2404/LTC2408's internal digital filter to place its first null precisely at 50Hz or 60Hz ±2%, achieving ≥110dB rejection. No external components are required. DC273A's layout preserves signal integrity for this critical timing path.

Can DC273A operate with an external reference voltage?

Yes, DC273A supports external reference voltages from 0.1V to VCC via the VREF header. The board includes optional zero-ohm jumpers to disconnect onboard REF02 (2.5V) or REF192 (4.096V) references and route an external source to the LTC2404/LTC2408 VREF pin. Input leakage current remains ≤±12nA, preserving accuracy. DC273A maintains proper decoupling and grounding for external reference stability.

What power supply requirements does DC273A have?

DC273A accepts a single 5V or 12V DC input via its barrel jack or terminal block. On-board regulators generate clean 5V and 3.3V rails for the LTC2404/LTC2408 and digital interface logic. Total quiescent current is <15mA in sleep mode and <35mA during active conversion. DC273A's power architecture mirrors production system constraints to ensure representative DC273A performance validation.