ROHM has expanded its range of sound processors (which have been well received by the market, with more than 120 million units supplied worldwide over the last 5 years) with the BD34602FS-M, which has been developed with special attention to sound quality, for which it uses its own sound quality design technology. 
Best-in-class features, such as low distortion of 0.004% and background noise of 3.1uVrms, allow it to extract all the data from sound sources, thus improving spatial representation (sound source localization and perceived distance). The result is improved in-car audio quality (which is experiencing increased demand), as well as promoting the adoption of high-resolution sound sources and reducing cabin noise.
Availability: current (samples and quantities for OEM manufacturers)
Main features
1. Achieve high-fidelity audio by incorporating sound quality design technology that optimizes its own parameters.
The BD34602FS-M integrates a new original audio quality technology. Extracting all the data from the audio sources by optimizing 28 unique parameters focused on the circuit configuration and electrical characteristics that have proven to affect the sound quality of the IC allows for an accurate spatial representation (perceived distance and location of the sound sources), and the result has been well received by car audio system manufacturers.
● Incorporates essential audio features
• Reduces bias circuit noise at the IC midpoint by approximately 20%
• Decreases low-frequency noise generated in the volume circuit by up to ten times
• Improves resolution (sound clarity) and spatial representation (localization and perceived distance from the sound), as well as transient characteristics by adopting a design that suppresses signal interference and allows all data to be extracted from the audio sources.
2. It offers the best performance on the market.
Many years of experience in analog design technology in areas that cannot be reproduced by simulations has allowed ROHM to develop car sound processors that achieve a distortion of 0.0004%, the lowest on the market, as well as a background noise of 3.1uVrms for volume attenuation.
3. Built-in mixing circuit that integrates original technology to reduce noise pops.
It incorporates a pop-up (mixing) function for voice navigation and hands-free modes.
Generally, unwanted noise pops can occur when switching the mix on and off, but with ROHM's original advanced switching technology, these pops are minimized.
*1: Variable volume gain between -79dB and +23dB and -∞ reduces noise pops.
*2: Minimizes noise pops when switching the mix on and off.
Terminology
High-resolution audio source
CD-quality audio sources are generally reproduced at a sampling rate of 44.1kHz and 16 bits, but with high-resolution audio sources, it is common to use sampling rates of 96kHz or higher and 24 bits. In other words, the amount of information contained in high-resolution audio sources is much greater, resulting in higher quality audio.
Distortion (total harmonic distortion)
represents the amount (degree) of signal distortion. The smaller this value, the lower the distortion.
Background noise
refers to the noise when there is no sound (when there is no input signal).
SoC (System on Chip)
This is generally an integrated circuit (IC) that integrates the functions necessary for the system to operate. In this case, it represents a series of functions that allow audio signals to be extracted from audio sources.
