2 x 100 mW class-D amplifer with analog or digital input, 2.0 multichannel digital audio processor with FFX

The STA529 is a digital stereo class-D audio amplifier. It includes an audio DSP, an ST proprietary high-efficiency class-D driver and CMOS power output stage. It is intended for high-efficiency digital-to-power-audio conversion for portable applications. The STA529 also provides output capabilities for FFX. In conjunction with a power device, the STA529 provides high-quality digital amplification.

The STA529 contains an on-chip volume/gain control.

The PWM amplifier achieves greater than 90% efficiency for longer battery life for portable systems.

The innovative class-D modulation, allows the STA529 to work without external LC filters and without a heatsink.

The STA529 I2CDIS pin disables the audio DSP functions and the I2C interface provides a direct conversion of the input signal into output power. This conversion is done without the microcontroller.

The STA529 is designed for low-power operation with extremely low-current consumption in standby mode. It is available in packages TFBGA48 and VFQFPN52. These are very thin packages (1.2 mm thick) ideal for small portable applications.

Key Features

  • Up to 96 dB dynamic range
  • Sample rates from 8 kHz to 192 kHz
  • FFX class-D driver
  • 1.55 V to 1.95 V digital power supply
  • 1.80 V to 3.60 V analog and I/O power supply
  • 18-bit audio processing and class-D FFX modulator
  • >90-dB SNR analog-to-digital converter
  • Digital volume control:
    • +36 dB to -105 dB in 0.5-dB steps
    • Software volume update
  • 16-bit ADC
  • Individual channel and master gain/attenuation
  • Automatic invalid input detect mute
  • 2-channel I2 S input/output data interface
  • Digitally controlled pop-free operation
  • 90% efficiency
  • Output power for stereo headphones or stereo speakers applications (at THD = 10% and VCC = 3.3 V):
    • 45 mW with 32-Ω headphones
    • 85 mW with 16-Ω headphones
    • 720 mW with 8-Ω speakers
    • 1.1 W with 4-Ω speakers

Circuit Diagram

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Technical Documentation

Product Specifications
Description Version Size
DB0353 DB0353: 2 x 100 mW class-D amplifier with analog or digital input 2.0 multichannel digital audio processor with FFX 1.3 81 KB
DS5050 DS5050: FFX™ audio codec with analog and digital inputs and 2 x 1.2 W (or 2 x 100 mW HP) class-D amplifier 3.0 509 KB
Application Notes
Description Version Size
AN4118 AN4118: APWLink USB interface board for Sound Terminal® demonstration boards 2.0 1 MB
AN2542 AN2542: Demo board BT-HTS-Rx_V1.0 for audio receiver using Bluetooth® wireless technology 2.2 766 KB
AN2612 AN2612: How to use the BT_HTS_RX_R2 evaluation board 1.2 1 MB
AN3984 AN3984: IIR filter design equations for Sound Terminal® devices 1.1 493 KB
AN3340 AN3340: Loudspeaker characterization and compensation 1.3 3 MB
User Manuals
Description Version Size
UM0457 UM0457: How to use the BT_HTS_RX_R2 1.2 376 KB
UM1545 UM1545: Using the Audio Processor Workbench (APWorkbench) 1.0 3 MB

Publications and Collaterals

Description Version Size
APWorkbench software for audio ICs and MEMS microphones 1.0 2 MB
Sound Terminal for portable audio 1.0 200 KB
Description Version Size
Analog audio solution 1.0 1 MB
FFX - Full flexible amplification 4 MB
FFX Full flexible amplification 1.0 4 MB
Support & Community

Sample & Buy

Part Number Marketing Status Quantity Unit Price (US$) * Package Packing Type Operating Temperature (°C) (min) Operating Temperature (°C) (max) ECCN (EU) ECCN (US) Country of Origin More info Order from ST Order from Distributors
STA529Q NRND 1000 2.841 VFQFPN2 52 8x8x1.0 Tray 0 70 NEC EAR99 - MORE INFO No availability reported, please contact our Sales office

(*) Suggested Resale Price per unit (USD) for BUDGETARY USE ONLY. For quotes, prices in local currency, please contact your local ST Sales Office  or our Distributors

Quality & Reliability

Part Number Marketing Status Package Grade RoHS Compliance Grade Material Declaration**
STA529Q NRNDVFQFPN2 52 8x8x1.0-Ecopack3

(**) The Material Declaration forms available on st.com may be generic documents based on the most commonly used package within a package family. For this reason, they may not be 100% accurate for a specific device. Please contact our sales support for information on specific devices.