Introduction to the Snapdragon Sound S5 Series of Bluetooth Audio SoCs

Introduction

Qualcomm has in the last five years began a heavy escalation of its line of Bluetooth audio SoCs. These are processors that are purpose built to power Bluetooth audio devices such as speakers, headsets, and earbuds.  Emphasizing and prioritizing this line of chips has changed some of the marketing terms used by Qualcomm. This article will focus on explaining the Snapdragon Sound S5 line of audio SoCs. We will cover where they came from, where they are, and where they are going.

Snapdragon Sound

To start with, let’s cover the current terminology. The Snapdragon Sound S5 series used to be referred to as the QCC5100 series. They have recently moved to the S5 brand for this line of products. Still, the products are labeled with the QCC51xx format. For example, the first LE Audio enabled part in the series is the QCC5171. In this article, I will use the terms Snapdragon S5 and QCC5100 interchangeablely.

Currently, under the Snapdragon Sound umbrrella, Qualcomm is marketing three separate solutions; Snapdragon S3, Snapdragon S5, and Snapdragon S7. These solutions are designed to target different sections of the Bluetooth audio market. Each line is meant to grow alongside each other. So the Snapdragon S3 solution will not be sunset by the Snapdragon S5 solution. Qualcomm plans to have the lines coexist.

The Snapdragon S3 line is targetted at products that have budget constraints. The Snapdragon S5 solution will be the premium tier alternative. You can see in the spec sheets, the QCC5100 series of Qualcomm parts has a programmable DSP, faster cores, and other features that allow it to address the needs of more premium products. To take it one step further, Qualcomm created the Snapdragon S7 line of products to offer an ultra-premium experience to consumers. We won’t get into those features, but they are extensive in order to address plans for AI informed Bluetooth audio products.

Snapdragon S5: The Past

The story of the QCC5100 series starts with a line of CSR branded audio chips. Two of the most popular CSR solutions include the CSR8635 and CSR8645. These were both processors aimed at an almost extreme SoC concept with limited programmability for budget devices. However, the CSR line of products also included a more powerful approach to the Bluetooth audio SoC concept. This secondary approach eventually grew into the extremely popular CSR8675. This line of products had support for programmable DSPs which further allowed manufacturers to differentiate their products. The CSR8675 was the last CSR branded chip in this evolution. The concept evolved into the first QCC5100 processor as the QCC5125.

At this moment, the QCC5125 is one of the most popular Qualcomm Bluetooth audio SoCs. It came out with more limited processing power than the QCC5124, but still supported ANC, aptx-LL (low latency), aptx-HD (high definition), and aptx-Adaptive. This made the QCC5125 a standout product in the premium tier Bluetooth audio chip space.

Snapdragon S5: The Present

The most current QCC5100 series solutions are the QCC5171 and the QCC5181. The dominant driving force for improvement in this line has focused on three major themes: lossless audio, power consumption, and audio over Bluetooth Low Energy (LE Audio).

The QCC5125 had a A2DP streaming power consumption of 10mA. Starting with the QCC5141, that power consumption was cut in half to 5mA. The QCC5181 has made a marginal improvement to 4mA at this benchmark.

In addition to improved power consumption, both the QCC5171 and the QCC5181 support LE audio and Auracast applications. This is a whole new approach to transmitting wireless music. Because these chips were some of the first movers on this huge shift, I believe these processors will become the defacto solution in the premium tier of headsets going forward.

Finally, the QCC5171 introduced aptx-lossless for Bluetooth Classic. The QCC5181 release took the concept one step further and added lossless audio to the LE Audio features.

Snapdragon S5: The Future

We don’t have any inside knowledge about what might be coming down the pipe, but I feel safe speculating on a few themes.

By looking at the Snapdragon S7 line, we can start to see that AI is making its way into these processors. I think it’s safe to say that AI will be working its way down into the S5 series as well.

I think looking at the latest State of Sound report from Qualcomm could be informative as well. In that document, the primary areas of concern for consumers centered around audio quality, battery life, and connection reliability. We can already see the new emphasis on lossless audio as a way to increase sound quality for consumers.

Along the same lines of addressing popular wireless audio complaints, there seems to be a push for including Qualcomm’s new advanced low power audio over WiFi (XPAN) on Snapdragon Sound processors. This could be seen as a means to increase connection reliability.

Also, I think there’s room for a low latency push on these processors that will be specifically catered to LE Audio. This would be similar to how Qualcomm started their lossless aptx work with Bluetooth Classic on the QCC5171 and moved to lossless compatibility on Bluetooth LE with the QCC5181.

Finally, almost certainly, the same themes of increased performance of existing DSP features like ANC, CvC, wake-word detection, virtual assistant applications, and power consumption will all be themes that Qualcomm will be pushing the envelope on.

Conclusion

It’s a long and winding road to follow along with the fast paced world of consumer technologies. Bluetooth audio is no different. I hope that this article can be a helpful way to navigate this world going forward. Anticipating these changes and knowing their history can be a powerful way to plan product roadmaps and ultimately win over customers with your solutions.

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