An Easy Path to Bluetooth 5-enabled SoC Design

Bluetooth (BT) was never a bit-player in communication but what surprised me is that is already dominating the market, at least as measured by radios sold, and is likely to extend that lead over the next 5 years. Particularly impressive is that BT already leads cellular and WiFi. This strength is certainly influenced by sales into IoT applications but also by what CEVA labels as IoD (internet of digital, that is non-IoT) devices where BT already plays an important role.

You can see where this strength is coming from in a forward-looking survey of applications. By 2021, smartphone applications will still contribute the largest component of volume, but after that, even when you drop PC-related categories there are applications for automotive, home automation, residential lighting, robotics, healthcare and many more. None of taken individually will be a major component of total volume, but there are so many active and growing applications that together they could amount to 50% of total volume.

Let’s start with a little terminology. The BT5 spec (in fact BT specs since 4.0) covers BT classic and BT low-energy (BLE). You can operate in pure classic mode, pure BLE mode or dual-mode. Classic is what made earpieces, speakers, wireless mice and other options so popular. BLE is a big part of what made BT a serious player in IoT. Dual-mode offers access to both options and is now common in smartphones, Bluetooth headsets/earbuds and speakers. An interesting point that initially confused me is that many of the features are optional per the standard, leading to potential confusion about what makes up BT5. In what follows, I will use the term to mean the full spec with all options.

The appeal of BT and the reason for this growth is in part that it offers low infrastructure cost because it can leverage existing hubs like smartphones, laptops, tablets and digital TVs (particularly where dual mode is supported in those hubs). It is low power (under 10mW at peak, down to uW in standby) and it offers robust and secure communication through frequency-hopping and built-in security/privacy features. BT5 builds on these existing strengths through even longer range (up to 1km line of sight), lower power and improved frequency-hopping through a more pseudo-random approach, supporting more devices communicating at the same time in a denser environment.

CEVA (Franz Dugand, Director connectivity BU) jointly presented with CSEM (Nicholas Raemy, head analog/RF design) in a webinar last week their joint solution for easy BT5 integration for BLE use-models. CEVA in their RivieraWaves product line-up provides the baseband controller and software. They also provide modem and RF blocks optimized for dual-mode use. The CSEM package adds modem and RF components optimized to BLE use. In either approach you can adopt the whole solution as a turnkey package or mix and match with your own or other IPs of your choice.

But if you do mix and match, CEVA advise you check specs carefully. Since many of the features are optional, an IP vendor can legitimately claim compliance with the standard without supporting all features. Naturally the solution offered here supports all features, including the optional ones, including among these all performance options and co-existence with 802.15.4 (ZigBee/Thread) and Wi-Fi.

The RivieraWaves baseband IP supports Bluetooth Low Energy, Bluetooth Classic and Bluetooth dual-mode and includes AES 128-bit encryption. Riviera Waves BT has a pretty impressive pedigree, licensing since 2000 and including Renesas, NXP, Spreadtrum and Atmel as customers, with 70+ design wins in PC, mobile, medical, automotive wearable and other applications.

The CSEM icyTRX IP offers a BLE solution for the modem and RF sections. This claims lowest power consumption in the market and a tiny form-factor, available in 65 or 55nm processes from several foundries. It is designed for a very simple interface with the CEVA baseband IP (9 signals) and can operate in low energy (1/2 Mbps) and long-range (500/125kbps) modes. CEVA and CSEM already have 6 customers for the joint solution.

Several general questions on the standard came up. I found the answers educational so I’ll add them here. One was on target applications for 2Mbps. Franz said that a big application will be firmware update over air, another would be for audio, e.g. for hearing aids. He also made an interesting comment on mesh support, noting that this is not directly part of the BT5 spec and can be done with existing chipsets. Smart mesh support is yet to be finalized in the standard and should be more efficient and provide better power management.

Applications for long-range support are particularly around home-automation, including long-range lighting, window/door control, temperature sensors and should be able to cover the outside area also, e.g. for watering controls. One other question was on whether smartphone vendors are offering BT5 yet. Franz said that those vendors are likely to be followers rather than leaders in this space since they will look for ecosystem support (which is one reason why dual-mode support continues to be an valuable option). He thought we may start to see smartphone options by the end of the year.

You can watch the Webinar HERE.