Analog Devices Inc. AD1839AS

Overview

AD1839AS from Analog Devices is a high-performance 24-bit sigma-delta audio codec integrating two stereo ADCs and three stereo DACs (six total DAC channels) in a single 52-lead MQFP package. It supports up to 96 kHz sample rates on all converters, with one DAC channel capable of 192 kHz operation, and delivers 105 dB SNR (ADC) and 108 dB SNR (DAC) for professional-grade audio acquisition and playback in multi-channel systems.

For engineers reviewing the AD1839AS datasheet, AD1839AS pinout, AD1839AS application, or AD1839AS equivalent, key selection considerations include its triple-stereo DAC architecture with independent 1024-step volume control per channel, flexible TDM/serial interface supporting 8-in/8-out operation, 3.3 V–tolerant digital I/O, and integrated 2.25 V reference with FILTD/FILTR filter pins for analog noise reduction.

Technical Context

The AD1839AS implements multibit Σ-∆ modulation with patented differential linearity restoration in both ADC and DAC paths, enabling −95 dB THD+N (ADC) and −92 dB THD+N (DAC) at 48/96 kHz. Its decimation filters provide 120 dB stop-band attenuation and linear phase response, while interpolation filters offer ±0.01 dB pass-band ripple and group delays of 460 µs (ADC @96 kHz) and 160 µs (DAC @96 kHz).

It features a dual-domain clocking architecture: MCLK input (up to 12.288 MHz) feeds an internal scaler generating IMCLK ≤24.576 MHz, and separate programmable master/slave modes for ADC (ABCLK/ALRCLK) and DAC (DBCLK/DLRCLK) serial ports support glueless interfacing to SHARC® SPORTs, AES/EBU receivers, and sample-rate converters via I²S, left/right-justified, DSP, or TDM protocols.

Key Specifications

Pinout & Package

AD1839AS is housed in a 52-lead MQFP (Metric Quad Flat Package) with exposed thermal pad, rated for −40°C to +85°C industrial operation. Pin functions are validated per Analog Devices Rev. B datasheet Figure 3 and Table 5.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multi-channel audio codec applications.

Compared with AK4384VN and CS4385A-KQZ, the AD1839AS uniquely combines dual ADC + triple stereo DAC in one IC with 3.3 V–tolerant I/O and industrial temperature rating - making it the only option for compact, self-contained, bidirectional high-res audio systems requiring minimal external components and wide environmental tolerance.

Availability

AD1839AS is available at Aetrix Electronics and suitable for DVD video/audio players, home theater receivers, and automotive infotainment systems requiring stable component supply, long-lifecycle assurance, and guaranteed industrial-temperature performance.

Supply support for AD1839AS 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. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA, with decades of expertise in precision data conversion and audio technology.

The AD1839AS belongs to Analog Devices' high-fidelity audio codec product line, designed specifically for professional and consumer multi-channel audio systems demanding simultaneous high-resolution analog input and output with minimal external circuitry and robust timing flexibility.

FAQ

What is the maximum sample rate supported by the AD1839AS ADC and DAC sections?

The AD1839AS ADC supports up to 96 kHz sample rate across both stereo channels. The DAC section supports up to 96 kHz on all six channels, with DAC1 additionally capable of 192 kHz operation when configured in 2× interpolation mode per the DAC Control 1 register. This asymmetric capability enables high-res playback on one channel while maintaining full 6-channel output at standard rates - a feature confirmed in the Rev. B datasheet Table 7 and Functional Overview section.

Does the AD1839AS require external op amps for analog output filtering?

Yes, the AD1839AS requires external third-order low-pass filters on each single-ended DAC output (e.g., OUTL1, OUTR1). Its outputs swing ±1.4 V around the 2.25 V common-mode voltage (2.8 Vp-p), and high-frequency noise from the sigma-delta modulator must be removed before connection to speakers or line inputs. The datasheet explicitly recommends a single op amp-based 3rd-order filter and warns against low-slew-rate op amps that may cause out-of-band noise folding.

How does the AD1839AS handle digital interface voltage level compatibility?

The AD1839AS supports mixed-voltage operation via the ODVDD pin (Pin 48), which powers all digital I/O buffers. ODVDD accepts 3.0 V to DVDD (5.0 V), allowing direct interfacing with 3.3 V DSPs, FPGAs, or microcontrollers without external level shifters. Input thresholds are specified at 2.4 V (VIH) and 0.8 V (VIL), ensuring reliable logic recognition across the 3.3 V/5 V boundary - a key design feature highlighted in the FEATURES and DIGITAL I/O specifications.

Can the AD1839AS operate with a single 5 V supply, and what are the grounding requirements?

Yes, the AD1839AS operates from a single 5 V supply applied to both AVDD and DVDD pins, though best practice separates analog and digital supplies for optimal SNR. It mandates strict grounding: six dedicated AGND pins (Pins 5, 10, 16, 24, 30, 34) and two DGND pins (Pins 40, 52) must be routed to separate ground planes, joined only at a single point near the power entry. This separation is essential to prevent digital switching noise from degrading the 105–108 dB dynamic range.

What is the function of the FILTD and FILTR pins on the AD1839AS?

FILTR (Pin 18) is the output of the on-chip 2.25 V reference voltage, requiring a parallel 10 µF + 100 nF capacitor to ground for stability and low-noise operation. FILTD (Pin 17) connects to an external capacitor (recommended 10 µF + 100 nF) that filters noise from the internal DAC bias circuitry - directly reducing DAC output noise floor. Both pins are critical for achieving the specified 108 dB DAC SNR and must be bypassed as close to the package as possible per the Power Supply and Voltage Reference section.