Analog Devices Inc. ADAU1446YSTZ-3A-RL

Overview

ADAU1446YSTZ-3A-RL from Analog Devices is a fully programmable SigmaDSP® digital audio processor with 24-channel digital I/O, no on-chip asynchronous sample rate converters (ASRCs), and operation in a single clock domain. It features a 172 MHz DSP core, 4 kB parameter RAM, 8 kB data RAM, flexible audio routing matrix (FARM), stereo S/PDIF I/O, TDM/serial audio interfaces up to 192 kHz, and self-boot capability from external EEPROM. It targets automotive head units and commercial DSP amplifiers requiring deterministic low-latency audio signal processing.

For engineers reviewing the ADAU1446YSTZ-3A-RL datasheet, ADAU1446YSTZ-3A-RL pinout, ADAU1446YSTZ-3A-RL application, or ADAU1446YSTZ-3A-RL equivalent, key selection criteria include its LQFP-100 package, absence of ASRCs, single-clock-domain constraint, 100% SigmaStudio™ compatibility, and integrated 1.8 V regulator for DVDD generation from 3.3 V.

Technical Context

The ADAU1446YSTZ-3A-RL implements a fixed-function audio routing architecture centered on the Flexible Audio Routing Matrix (FARM), which enables dynamic multiplexing of up to 24 input and 24 output channels between serial/TDM/S/PDIF interfaces and the SigmaDSP core. Unlike the ADAU1442/1445, it omits all ASRC hardware blocks-eliminating sample rate conversion flexibility but reducing power and complexity for systems with synchronized clocks.

Its timing architecture relies on a crystal oscillator (XTALI/XTALO) and PLL to derive the 172.032 MHz core clock from common audio master clocks (e.g., 12.288 MHz), supporting synchronous I²S/TDM operation across one clock domain only. Control is handled via SPI/I²C, with standalone boot enabled through ADDR0/ADDR1/CLATCH pins and external EEPROM.

Key Specifications

Pinout & Package

ADAU1446YSTZ-3A-RL is housed in a 100-lead LQFP package (14 mm × 14 mm, 0.5 mm pitch) with exposed thermal pad (no internal electrical connection, must be soldered to PCB ground plane).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar digital audio processor applications.

Compared with ADAU1442YSTZ-3A-RL and ADAU1467WBCPZ-RL, the ADAU1446YSTZ-3A-RL trades ASRC flexibility and raw compute for lower power (315 mA max DVDD), simplified thermal design, and reduced BOM cost - making it optimal for cost-sensitive, single-clock-domain automotive and commercial audio systems where external clock alignment is feasible.

Availability

ADAU1446YSTZ-3A-RL is available at Aetrix Electronics and suitable for automotive head units, commercial DSP amplifiers, rear-seat entertainment systems, and navigation system audio requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for ADAU1446YSTZ-3A-RL 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 semiconductor leader specializing in high-performance analog, mixed-signal, and digital signal processing technologies for precision instrumentation, industrial automation, and communications infrastructure.

The ADAU1446YSTZ-3A-RL belongs to the SigmaDSP® family, designed specifically for cost-optimized, low-latency audio signal processing in automotive and commercial audio systems where deterministic timing and minimal external components are critical.

FAQ

What is the primary functional distinction of ADAU1446YSTZ-3A-RL within the ADAU1442/1445/1446 family?

The ADAU1446YSTZ-3A-RL is uniquely defined by its absence of asynchronous sample rate converters (ASRCs) and operation in a single clock domain - unlike the ADAU1442 (16 ASRCs, 8 domains) and ADAU1445 (16 ASRCs, 2 domains). This simplifies clock tree design and reduces power consumption to 315 mA maximum DVDD current, making ADAU1446YSTZ-3A-RL ideal for systems with globally synchronized audio clocks and strict thermal budgets.

Does ADAU1446YSTZ-3A-RL support self-boot, and what external components are required?

Yes, ADAU1446YSTZ-3A-RL supports self-boot from an external SPI EEPROM using the ADDR0, ADDR1, and CLATCH pins. Required external components are a 10 kΩ pull-up resistor on RESET, 100 nF decoupling capacitors on each DVDD/IOVDD/AVDD pin, and a fundamental-mode crystal (e.g., 12.288 MHz) on XTALI/XTALO. No external voltage regulators are needed due to the on-chip 1.8 V DVDD regulator.

Can ADAU1446YSTZ-3A-RL process audio at 192 kHz, and what interface modes are supported?

Yes, ADAU1446YSTZ-3A-RL supports digital audio I/O up to 192 kHz via its serial and TDM ports. It operates in I²S, left-justified, right-justified, and flexible TDM modes (up to 32 slots per frame), with configurable BCLK/LRCLK ratios. All timing specifications - including tBCLK (40.69 ns min), tSIS (10 ns setup), and tSODM (30 ns output delay) - are validated for 192 kHz operation per the Rev. D datasheet.

How does the Flexible Audio Routing Matrix (FARM) function in ADAU1446YSTZ-3A-RL given the lack of ASRCs?

In ADAU1446YSTZ-3A-RL, the FARM operates strictly within a single clock domain, routing 24-channel digital inputs (from SDATA_IN[0:8], SPDIFI, or internal sources) directly to the SigmaDSP core or to 24-channel outputs (SDATA_OUT[0:8], SPDIFO) without sample rate translation. Signal paths are reconfigurable in real time via control registers, enabling dynamic source switching and mixing - but all connected peripherals must share the same master clock frequency and phase alignment.

What are the thermal characteristics of ADAU1446YSTZ-3A-RL, and how should the exposed pad be handled?

ADAU1446YSTZ-3A-RL in LQFP-100 has θJA = 41.4°C/W and θJC = 9.5°C/W. The exposed thermal pad has no internal electrical connection but must be soldered to a solid PCB ground plane with ≥6 thermal vias (0.3 mm diameter, spaced ≤2 mm apart) to achieve rated thermal performance. Failure to connect the pad increases junction temperature by >25°C under full load, risking thermal shutdown or accelerated aging.