Analog Devices Inc. DC941A

Overview

LTC2482 from Analog Devices (acquired Linear Technology) is a 16-bit + sign delta-sigma ADC with Easy Drive input current cancellation, enabling rail-to-rail differential inputs with zero net differential input current. It delivers 600nV RMS noise, 2ppm INL, and simultaneous 50Hz/60Hz line rejection - ideal for high-impedance sensor digitization in industrial weighing systems and precision instrumentation.

For engineers reviewing the LTC2482 datasheet, LTC2482 pinout, LTC2482 application, or LTC2482 equivalent, this page provides verified technical context, validated pin functions, confirmed timing behavior under internal/external clock modes, and real-world design implications of its no-latency digital filter and GND-to-VCC common-mode range.

Technical Context

The LTC2482 employs a third-order delta-sigma modulator with on-chip auto-calibration that continuously corrects offset and full-scale errors without interrupting conversion flow. Its patented Easy Drive sampling scheme cancels differential input current dynamically, eliminating need for external buffers when interfacing to strain gauges or thermocouples.

It operates with an internal 307.2kHz oscillator (enabling 87dB 50Hz/60Hz rejection) or accepts external fO clock signals (10–4000kHz), shifting notch frequency to fEOSC/5120 for custom line-noise suppression. The 24-bit serial output includes EOC, sign, MSB, and over/underrange flags - all synchronized to SCK edges with sub-200ns timing margins.

Key Specifications

Pinout & Package

Package: 10-lead (3mm × 3mm) plastic DFN with exposed pad (Pin 11 = GND). Pin 1 is functional GND but may be driven for LTC2480/LTC2484 pin compatibility.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-precision delta-sigma ADC applications.

Compared with ADS124S08 and MAX11200, the LTC2482 uniquely combines 16-bit precision with zero-differential-input-current operation, integrated oscillator-based 50/60Hz rejection, and no-latency filtering - making it optimal for single-sensor, space-constrained, high-accuracy industrial transducer interfaces where minimal external components and guaranteed AC-line immunity are critical.

Availability

LTC2482 is available at Aetrix Electronics and suitable for weight scales, strain gauge interfaces, direct temperature measurement, and industrial process control systems requiring stable component supply, long-term calibration retention, and immunity to 50Hz/60Hz interference.

Supply support for LTC2482 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. (ADI) is a global leader in high-performance analog, mixed-signal, and digital signal processing technologies, serving industrial, automotive, communications, and healthcare markets.

The LTC2482 belongs to ADI's precision delta-sigma ADC product line, designed specifically for direct digitization of high-impedance sensors in harsh industrial environments where rail-to-rail input range, low drift, and inherent line-frequency rejection are essential.

FAQ

What is the minimum reference voltage supported by the LTC2482?

The LTC2482 supports reference voltages as low as 100mV while maintaining full 16-bit resolution and accuracy. This capability enables direct digitization of low-level sensor outputs - such as thermocouples or microvolt-level bridge imbalances - without amplification stages that introduce noise and offset drift. The LTC2482's 600nV RMS noise remains independent of VREF, ensuring consistent noise performance regardless of reference choice.

How does the Easy Drive technology in the LTC2482 eliminate differential input current?

The LTC2482 implements a patented passive sampling network that automatically cancels differential input current through synchronized capacitor switching, eliminating dynamic current errors without on-chip buffers. This allows the LTC2482 to interface directly with high-impedance sources like strain gauges or thermistors - even with mismatched source impedances - while preserving DC accuracy and rail-to-rail input range. The LTC2482 achieves zero net differential input current across temperature and supply variations.

Can the LTC2482 reject both 50Hz and 60Hz line noise simultaneously?

Yes, the LTC2482 achieves simultaneous 87dB rejection of both 50Hz and 60Hz line frequencies using its internal 307.2kHz oscillator. This is implemented via a fixed digital filter notch centered at fOSC/5120, which inherently covers both fundamental frequencies and their harmonics up to the 255th order. No configuration or external components are required - the feature activates automatically when fO is tied to GND. This makes the LTC2482 uniquely suited for global industrial equipment deployed across 50Hz and 60Hz power grids.

What happens to the LTC2482's output data format during a conversion overrun?

When the differential input voltage exceeds ±FS (±0.5×VREF), the LTC2482 outputs clamped codes: VIN ≥ +FS produces the +FS + 1LSB code, and VIN ≤ –FS produces the –FS – 1LSB code. Bits 21 and 20 jointly indicate overrange (both high) or underrange (both low) conditions in the 24-bit serial stream. This deterministic saturation behavior ensures predictable fault detection in safety-critical applications - unlike soft-clipping architectures - and is fully documented in Table 1 and Table 2 of the LTC2482 datasheet.

Does the LTC2482 require external components for basic operation?

The LTC2482 requires only two external capacitors for stable operation: a 1μF tantalum and 0.1μF ceramic capacitor between VCC (Pin 2) and GND (Pin 8), placed as close as possible to the device. All other functionality - including oscillator, auto-calibration, digital filtering, and serial interface timing - is fully integrated. No external crystal, reference buffer, or input amplifier is needed, enabling compact, low-component-count designs for space-constrained industrial modules.