Texas Instruments Audio Solutions Guide

Home Theater

The emergence and rapid acceptance of digital media such as the DVD format have been a catalyst for the home theater market. One of the most important functions in home theater systems is the audio-visual (AV) receiver, the engine behind the life-like high fidelity surround sound demanded by today's consumer.

Receivers, available as a separate component (AV receivers) or integrated with DVD players in a single chassis (DVD receivers), control various components in a typical home theater system, decode compressed audio signals using standard algorithms such as Dolby and DTS, perform post-processing on these signals, and also amplify audio signals and drive loudspeakers.

Separate AV receiver component systems offer the greatest choice in terms of input and output selection, decoder and software functions, and audio quality. Consumers can mix-and-match various system components to customize their system setup and sound quality for their listening environment and budget.

DVD receivers provide a highly integrated, compact system that is easy to set up and often offers a wide variety of software features and listening options. The unique requirements of the DVD receiver (small, compact, high functionality, high power output) present several challenges to designers that TI audio solutions can help overcome.

The receiver and surround-sound decode markets are growing rapidly. This growth is driven by trends including: the move to a digital signal chain fueled by digital media and content (DVD), the demand for a more lifelike listening experience requiring more channels and higher arithmetic precision, and the proliferation of decoding standards leading to sticker races between equipment makers.

Meeting market windows and releasing feature-rich differentiated products on time is a challenge. Manufacturers need advances from suppliers: higher performance scalable audio processing solutions, shorter development cycles, and easier development processes. Whether designing high fidelity receivers for discerning audiophiles or cost-driven feature-rich systems for the mass market, TI's audio DSP, digital amplifiers, and analog solutions for the home theater space help meet and exceed design goals.

Key Components for Home Theater:

• PCM1602 100-multichannel DAC (Page 10)
• TAS5026 Digital Amplifier PWM (Page 6)
• TAS5110 Digital Amplifier H-Bridge (Page 7)
• TMS320DRE200 DSP (Page 28)
• TMS329DA61x DSP (Page 6)
• PCM1742/48 DAC (Page 10)
• DIR1703 Interface Receiver (Page 7)
• DSD1702 DAC (Page 9)
• PCM1606 DAC (Page 10)
• PCM1738 DAC (Page 8)

Block Diagram of a Typical AV Receiver

The block diagram illustrates the signal flow in a typical AV receiver. It shows inputs like DVD Drive, Digital inputs (Optical, Digital Radio, S/PDIF), and Analog inputs (5.1 Analog In). These signals are processed by components like the DIR1703 Digital Audio Interface Receiver, PCM1804 ADC, and the TMS320DA610 DSP. The output stages include Digital Amplifiers (TAS5110, TAS5026) and a Power Stage, leading to loudspeakers. The diagram also shows the DSP's connection to Power Management and a Multiplexer for analog-to-digital conversion.

AV and DVD Receivers Overview

TI offers a complete solution addressing the entire signal chain in AV receiver systems.

Audio DSP

The TMS320DA610 32-/64-bit floating-point audio DSP delivers 3x the performance of existing solutions, operating at 225 MHz with 1800 MIPS or 1350 MFLOPS. It integrates 3Mb of RAM, 2Mb of ROM, and multichannel audio ports. This enables single-chip solutions for advanced features like automatic room correction and speaker virtualization, reducing Bill of Materials (BOM) and design complexity.

Digital Amplifiers

Highly efficient, low-profile digital amplifiers are key to fitting AV and DVD receiver functionality into compact chassis, reducing the need for bulky transformers and heatsinks found in older linear amplifiers. TI offers digital amplifier devices from 30W to 50W, with a 100W power stage planned for 2Q '02. A six-channel Digital Audio PWM Processor with integrated volume control is also available.

Analog and Digital Inputs

Burr-Brown products from TI provide high-performance, low-cost ADCs. The digital interface benefits from the SpAct™ clock recovery system, reducing sensitivity to input jitter on S/PDIF data, making S/PDIF a more robust interface.

Processing Audio Software

TI provides comprehensive audio decoding software, including Dolby and DTS suites, and an open audio software framework for rapid system setup and feature changes.

Generating the Outputs

Burr-Brown DACs cover the performance spectrum for headphone and analog recording outputs. Multichannel analog outputs are provided by six- and eight-channel converters.

Highest Performance DSP Enables Lifelike Sound at Lower Costs (TMS320DA61x)

The TMS320DA61x DSP offers unparalleled performance and integrated peripherals for higher quality, more features, faster time-to-market, and lower overall costs. Key features include 1500 MFLOPS/2000 MIPS for integrating features like multiple digital zones of audio decode and speaker virtualization, lifelike sound recreation with up to 64-bit words, an open and scalable software solution, easy-to-use development tools, reduced DSP and microcontroller counts, two multichannel audio serial ports (McASP), and two I2C interfaces.

TMS320DA61x Floating-Point DSP Block Diagram

The block diagram shows the TMS320DA61x DSP architecture, including the EMIF, McBSP, McASP, HPI, GPIO, Enhanced DMA Controller, Cache/Memory, DSP Core, ROM, and Timers. It highlights the integration of peripherals for audio processing.

Six-Channel Digital Audio PWM Processor (TAS5026)

The TAS5026 is a six-channel digital audio PWM processor designed for DVD and AV receivers, offering independent volume control for each channel. Key features include PWM processing, high audio performance (96 dB SNR, 0.06% THD+N), support for 32-kHz to 192-kHz sampling rates, 16-, 20-, or 24-bit operation, low EMI design, and click-and-pop-free performance. Applications include DVD receivers, AV receivers, mini-/micro-components, home networking, and digital radio.

TAS5026/36 Block Diagram

This block diagram illustrates the TAS5026/36 PWM processor, showing the PLL/Clock Generator, Serial Audio Port, Digital Interpolation Filter, Equibit Modulator, Buffer, and Control Section, leading to PWM outputs.

Digital Mini-/Micro-Component Systems

The evolution of digital audio is driving major changes in mini- and micro-component systems, responding to consumer demand for new features like encoded audio CD playback, smaller products, enhanced sound field processing, and digital sources such as MiniDisc and USB. The shift to digital technology is essential for keeping up with audio innovations. As the world moves to digital sources and interfaces (CD, DVD Audio, MiniDisc, SACD, USB, S/PDIF), system architectures must become digital to enable higher audio quality and new features.

Key Components:

• TAS5001 digital PWM processor (Page 15)
• TAS5101 digital PWM processor (Page 15)
• TAS3103 digital audio processor (Page 14)
• TMS320DA61x DSP (Page 6)
• PCM2702 USB interface (Page 14)

Digital Mini-/Micro-Component System Block Diagram

This block diagram shows a typical system, including inputs like AM/FM Tuner, USB, Tape, CD/DVD, and Mini Disk. These connect to an Analog Mux, Stereo ADC, Digital Audio Processing (TAS3001/2/4, TAS3103), Headphone Amplifier (TPA611xA2), Digital Amplifier (TAS5001, TAS5101), and a Battery-to-USB Power Switch. The diagram emphasizes how digital processing and amplification enable new product features and smaller solutions.

USB DAC and USB Codec

TI offers the PCM2702 (stereo USB DAC) and PCM2901 (stereo USB Codec) for easy integration of USB audio interfaces into mini-/micro-component systems. These require no programming, speeding up time-to-market.

Stereo Analog-to-Digital Converters (ADCs)

Burr-Brown ADCs, like the PCM18xx series, offer performance from 93 dB to 110 dB dynamic range, fitting various consumer audio applications.

Digital Audio Processors

Digital audio processors enable feature-rich, cost-competitive products. The TAS3103, a 48-bit DSP with a 76-bit accumulator, offers 135-MIPS processing, supports 8 kHz to 96 kHz sample rates, and is register-controlled via I2C, requiring no programming. It enables features like 5.1 to stereo conversion, stereo enhancement, and bass management.

Digital Amplifiers

Digital amplifiers are transforming home audio with compact, lightweight products. TI's solutions, like the TAS5001 PWM and TAS5101 H-Bridge, offer powerful stereo output with high efficiency, often requiring no heatsink or fan. TI's approach ensures EMI compliance without shielding.

Internet Audio Players

The portable Internet audio player market has exploded, driven by new technologies and design challenges. Modern portable audio systems rival the processing power of early supercomputers. Factors contributing to portable audio's success include audio-friendly compression, inexpensive mass storage, battery-friendly processors, and integrated analog output technology. The industry faces complexity in processing and design due to evolving audio formats (MP3, WMA, AAC) and Digital Rights Management (DRM).

TI understands that designers need to focus on unique product aspects for a time-to-market advantage. TI's complete audio solutions for portable audio aim to achieve goals like benchmark vendor tools, scalable processing engines, high reuse, integrated systems-on-chips, and shorter development cycles.

Key Components:

• TPA2000D1 audio power amp (Page 20)
• TLV320AIC23 stereo audio Codec (Page 19)
• PCM177x DAC (Page 19)
• PCM3008 stereo audio Codec (Page 20)

Internet Audio/Portable Player System Diagram

This diagram shows a typical portable player system, including a LCD, USB Connector, EEPROM, Mass Storage, DSP (TMS320DA250), Codec (TLV320AIC23), Headphone Amplifier, and Power Supply components. It highlights the flow of audio signals and control data via a USB interface.

Processing the Audio DSP

Building on the TMS320DA150, the TMS320DA250 is a fourth-generation, dual-MAC, 16-bit fixed-point audio DSP delivering close to 200 MIPS. It integrates USB 2.0 client controller, real-time clock, watchdog timer, and 10-bit ADC. TI's TMS320DAx family offers optimal performance, peripheral options, small packaging, and power efficiency for portable digital audio markets.

Low-Power Codec with Integrated Headphone Amplifier

The TLV320AIC23 Codec offers low power dissipation (23 mW playback) and integrated headphone and microphone amplifiers, fitting into a small package. It provides 90-dB SNR ADC and 100-dB SNR DAC, programmable gain, and power-down modes. The TLV320DAC23 is an alternative for applications not requiring an ADC, while the PCM177x family offers even lower power dissipation.

Cellphone Audio Player Block Diagram

This diagram illustrates a cell phone audio player, showing a Cellphone Host Processor, UART, DSP (TMS320DA105/150), USB (TAS1020), Codec (TLV320AIC23), Class D Amp (TPA2000D4), and other components. It emphasizes the importance of low power dissipation and feature enhancement for cell phones.

TMS320DA250 Block Diagram

The block diagram details the TMS320DA250 DSP, showing its CPU, memory (ROM, DARAM, SARAM), DMA, EMIF, McBSP, I2C, Timer, USB, and PLL interfaces, illustrating its comprehensive capabilities for audio processing.

Internet Audio CD Players

The invention of CDs in the early 1980s necessitated digital audio storage. The CD-DA (Red Book) standard holds about 60 minutes of audio. Yellow Book extended CD capabilities for data (CD-ROM). While Red Book limits WAV files to one hour, Yellow Book supports MP3, AAC, and WMA for up to 10 hours. Consumers desire this longer storage and the ability to burn CDs using CD-R/RW media, driving market growth.

Consumers are demanding more from their listening experience, seeking products that support evolving standards, digital security, and enriched functions like anti-shock. TI offers DSP-enabled CD audio solutions to meet these challenges, enabling OEMs to deliver innovative products quickly. TI's DSP-based solutions provide low-power, high-performance, and flexible features for faster market entry.

Key Components:

• TPS6200x DC/DC converters (Page 24)
• bq2057 charge management (Page 25)
• TPA611xA2 headphone amp (Page 25)
• TLV320DAC23 DAC (Page 29)
• PCM177x DAC (Page 19)

Internet Audio CD System Diagram

The system diagram for an audio CD player shows the hardware architecture, including the spindle motor, CD mechanism, servo controller, pick-up, decoder for compressed audio, user interface controller (LCD/keypad), and audio playback path with DACs, amplifier, and power management. The TMS320C5000™ DSP acts as the decoder and controller.

Analog and Digital Inputs

Burr-Brown products provide high-performance ADCs. The SpAct™ clock recovery system enhances S/PDIF interface robustness by reducing sensitivity to input jitter.

Processing the Audio DSP

The TMS320DA150 DSP is a 16-bit fixed-point audio DSP delivering 160 MIPS, integrating RAM, ROM, multichannel serial ports, HPI, and DMA. It enables advanced features like UDF file system, anti-shock buffering, and software upgradeability via CD. The DA product family roadmap includes higher performance options like the TMS320DA250.

Processing Audio Software

TI provides comprehensive audio encoding/decoding software, content protection, DRM systems, speech coders, and audio post-processing algorithms, along with CD-ROM decoding and CD control software.

Digital Radio

Eureka DAB digital radio offers listeners more stations and higher fidelity sound, transforming radio into a personal communication and information delivery system. Usage of the Eureka DAB standard has grown significantly, with adoption in Europe, Asia, and North America. Germany's analog shutoff is expected within 10 years, projecting explosive growth in digital radio receiver sales.

The industry needs affordable, portable, and full-featured digital products. Designers require inexpensive, power-efficient, easy-to-use, and flexible solutions. A complete RF design, digital baseband, ADC, MPEG1 layer 2 decoded output to DAC, amplifiers, and power regulation are necessary for a digital radio system.

Key Components:

• PCM1606 DAC (Page 10)
• TMS320DA61x DSP (Page 6)
• TMS320DRE200 DSP (Page 28)
• TPA6010A4 audio power amp (Page 28)
• TLV320DAC23 DAC (Page 29)
• PCM1725/33/44 DAC (Page 29)

Eureka System Block Diagram

This diagram outlines TI's complete solution for a digital radio, based on a TI DSP. It shows the RF Front End, RF ADC, Power Amp, DAC, and various digital processing blocks like FFT/Demux, Synchronization, Deinterleaver/Viterbi, System Control, and Audio/PAD Decoder. It also indicates inputs for music, news, traffic, and weather data.

Digital Radio Products

TI, in partnership with Radioscape, offers the TMS320DRE200 for a complete digital radio solution, featuring low bill of materials, low system power consumption, and flexibility for easy implementation of functions beyond digital radio.

TMS320DRE200 Digital Baseband

The ETSI 300 401-compliant TMS320DRE200 baseband decodes channels and sources on a single chip, supporting Eureka modes and user interface functions. It requires no external memory for DAB operation and can interface with external microcontrollers. It offers disturbance-free operation and low power consumption (<175 mW baseband, <1 mA standby).

TMS320DRE200 Software

TI provides an open, software-driven Eureka DAB digital radio receiver solution, allowing easy updates, flexibility to add feature modules, and integration of multiple functions on a single chip.

TMS320DRE200 Analog

TI also provides the ADC, DAC, power amplifier, and power management devices for digital radio applications, offering a bundled solution for lowest system cost.

Advanced Stereo Audio Power Amp (TPA6010A4)

The TPA6010A4 is a stereo audio power amplifier delivering 2W RMS into 3- loads, optimized for digital radios. It features integrated stereo headphone drive, DC volume control, bass boost, and fully differential inputs.

Stereo Audio Power Amplifier for Digital Radios Table

This table compares various stereo audio power amplifiers (TPA6010A4, TPA0112, TPA0212, TPA0132, TPA0232, TPA0152, TPA0252) based on Output Power, DC Volume Control, Digital Volume Control, Gain Control, Bass Boost, Differential Inputs, Stereo Inputs, Docking Station Outputs, and Stereo Headphones.

USB Headsets

New gaming consoles and PC applications are driving the demand for higher quality audio headsets. USB headsets offer a simple, clean user interface with voice and control data over a single wire. Designers face challenges such as meeting USB power requirements, providing user feedback (power/mute indicators), limiting USB power draw before enumeration, and ensuring software compatibility across platforms.

Users expect better performance and new features from USB headsets. Providing microphone feedback to the earpiece is important for user experience. TI has developed a USB headset reference design to speed customers to market with reliable and flexible solutions.

Key Components:

• TPA610xA2 audio power amp (Page 36)
• TAS1020 audio interface (Page 36)
• PCM390D USB Codec (Page 37)

USB Headsets Architecture

USB headset architectures generally share common design blocks. Audio signals are transmitted via a USB interface, which acts as a system controller, interfaces with LEDs/buttons, and manages power sequencing. Playback audio data also needs synchronization.

USB Headset Products

TI provides complete USB headset solutions. Options range from highly integrated, cost-effective solutions like the PCM2900 (requiring no programming) to the versatile and programmable TAS1020, which allows for tailored solutions and field upgrades.

Power Supply Voltage Regulator

The TPS78833 voltage regulator is designed for USB bus-powered applications, providing up to 150 mA of regulated 3.3-V power and controlling USB inrush current.

USB Firmware & Host Software Drivers

TI offers programmable solutions and example firmware under a no-cost license agreement. The USB headset reference design demonstrates features without requiring special host drivers.

Driving the Headphones

TI offers an extensive headphone driver portfolio. The TPA6102A2 is suitable for USB headsets, providing up to 50 mW of driving power and excellent audio performance, with a low power shutdown state for USB bus-powered applications.

Low Voltage Headphone Amp (TPA610xA2)

The TPA610xA2 family operates from a 1.6-V to 3.6-V supply, delivering 50 mW per channel into 16- loads. The TPA6101A2 and TPA6102A2 save board space by internally setting amplifier gain, eliminating external resistors.

Programmable USB Audio Interface (TAS1020)

The TAS1020 IC is a USB peripheral interface device for isochronous data streaming. It complements the TUSB3200, offers on-chip clock generation, and supports AC97 or I2S Codecs. It allows general-purpose interfacing with devices like TI's TMS320C54x™ DSPs and includes an integrated DMA controller for efficient data transfer.

Single-Chip, Stereo Audio Codec (PCM2900)

The PCM2900 is a single-chip stereo audio codec with an integrated USB 1.1-compliant interface controller, using SpAct™ technology for outstanding audio quality. It supports sampling frequencies from 8 kHz to 48 kHz for playback and record, requires no programming, and supports HID volume/mute controls.