High Quality Sound D/A Converter dedicated to True Wireless Earphones


Low-power HiFi Headphone DAC for true wireless earphones

New Product


The AK4332 is an advanced 32-bit high sound quality mono audio DAC with a built-in ground-referenced headphone amplifier. It has four types of 32-bit digital filters for better sound quality, achieving low distortion characteristics and wide dynamic range. The AK4332 accepts PCM Data, PDM Data and DSD Data. It is available in a 30-pin CSP package, utilizing less board space than competitive offerings. It is ideal for true wireless earphones, (TWS: True Wireless Stereo).

High Performance of -101dB THD+N with only 2.8mW Power Consumption

VELVET SOUND technology is optimized in pursuing high quality sound and high performance for TWS. The AK4332ECB achieves high performance of -101dB THD+N and 109dB SNR with the industry's most advanced level of ultra-low power consumption at 2.8 mW. This will enable TWS playback for long times with high quality sound.

Capable of Achieving Even Lower Power Consumption with support of a 1-bit PDM signal

Further low power consumption is achieved by executing digital signal processing of the digital filtering and ΔΣ modulation with a Bluetooth SoC which utilizes small geometry transistors.


True Wireless Earphones

Key Features

  • Maximum Sampling Frequency/Resolution :  192kHz/32-bit
  • S/N (SNR) :  109dB
  • Distortion (THD+N) :  -101dB
  • Sound Color Digital Filter :  4 types
  • Power consumptoin :  2.8mW (fs=48kHz)

Block Diagram


Main Specifications

Part Number
DAC  32-bit Stereo Portable
 Audio D/A Converter
 32-bit Mono Portable
 Audio D/A Converter
Sound Color  Four Types of Digital Filters
 - Acoustic Sound (Short Delay Sharp Roll-off, GD = 5.5/fs)
 - Acoustic Tone (Short Delay Slow Roll-off, GD = 4.5/fs)
 - Traditional Sound (Sharp Roll-off)
 - Traditional Tone (Slow Roll-off)
Headphone Amplifier  Ground Referenced Class-G Headphone Amplifier
 - Output Noise Level: -114dBV (Analog Volume = -10dB)
 - Analog Volume: +4 to -10dB, 2dB Step
Output Power: 70mW with 8Ω  Output Power: 88mW with 8Ω
THD+N (Total Harmonic Distortion Pulse Noise)  -100dB  -101dB
SNR  109dB
Sampling Rate  Maximum 192kHz Master/Slave Mode
Jitter Cleaning Function  Available
 Asynchronous Sample Rate Converter
 Crystal Oscillator
Low Jitter PLL  Available
Digital MIC Interface  Available  None
Digital Audio Interface  PCM Input  PCM Input
 PDM 1-bit Input
 DSD Input
Resolution  32-bit
Number of Channels  2ch  1ch
Microcontroller Interface  I2C (400kHz)
VELVET SOUND Technology  Low distortion Technology
 OSRD (Over Sampling Ratio Doubler) Technology
Power Consumption  4.4mW (fs = 48kHz)  2.8mW (fs = 48kHz)
Power Supply  AVDD = CVDD = LVDD = 1.7 to 1.9V
 TVDD = 1.65 to 3.6V
 AVDD = CVDD = LVDD = 1.7 to 1.9V
Operation Temperature Range  -40 to 85°C
Package  36-pin CSP
  (2.533 × 2.371mm, 0.4mm pitch)
 30-pin CSP
  (2.371 × 1.971mm, 0.4mm pitch)
Mass Production  Now  Summer, 2019

Related Contents

Datasheet Download



VELVET SOUND is a sound philosophy and brand concept for AKM’s next-generation audio devices, featuring new chip architectures and core technologies.

The new circuitry found in VELVET SOUND devices is designed to maximize dynamics and ensure pure, unaltered audio data, prioritizing the accurate capture and reproduction of the source material in order to achieve high performance and rich musicality. These devices were designed specifically for the high-resolution digital audio era.

* VELVET SOUND ™, VELVET SOUND | VERITA ™ and Audio 4 Pro ™ are trademarks of Asahi Kasei Microdevices Corporation in Japan, Europe and the United States.