BT850 Series Bluetooth Module

Recommended for New Design (RND)

Overview

The BT85x series of USB HCI modules and Adapter leverage the Cypress CYW20704 A2 chipset to provide exceptionally low power consumption with outstanding range for OEMs needing both Classic Bluetooth and Bluetooth Low Energy support. The Bluetooth 5 core specification shortens your development time and provides enhanced throughput, security and privacy. The BT850 modules are ideal when designers need both performance and minimum size. For maximum flexibility in integration, they support a host USB interface, I2S and PCM audio interfaces, GPIO, and Cypress' GCI coexistence (2-Wire). The modules provide excellent RF performance and identical footprint options for integrated antenna or an external antenna via a trace pin.

These modules present a Bluetooth standard HCI interface with native support for Windows, Linux and Android Bluetooth software stacks for operating system backed devices. The BT851 Pluggable USB Adapter simply plugs into any Windows, Android or Linux device via external USB connection. Additionally, Laird has partnered with SEARAN for support of their ultra small, flexible ‘dotstack’ platform for embedded Cortex M3 and M4 implementations. 

Two form factors: BT850 Module or BT851 packaged USB Adapter.

 

 

Specifications

Antenna Options
Integrated or External via SMT Pad
BLE Connections
Yes
Bluetooth Version
5.0
BT Class
1
BT Connections
7
Certifications
FCC, ISED, EU, UKCA, MIC, KC, AS/NZS, Bluetooth SIG
Chipset
Cypress CYW20704 A2
Dimension (Height - mm)
2.2 mm
Dimension (Length - mm)
8.5 mm
Dimension (Width - mm)
13 mm
Dual Mode
Yes
Logical Interfaces
USB (v2.0), GPIO, GCI, I2S, PCM
NFC
Yes
Processor On Board
No
Receive Sensitivity
-94 dBm
Stack On Board
No
Temperature Range
-30°C to +85°C
Transmit Power
8 dBM
Wi-Fi Coexistence
Yes
Product Type Technology OS/Software System Architecture Chipset (Wireless) Antenna Type Logical Interfaces Frequency Range (Min) Frequency Range (Max) Antenna Options Dimension (Height - mm) Dimension (Length - mm) Dimension (Width - mm) Type
BT850-SA Embedded Module Blutooth 5.0, Dual Mode (Classic + BLE) HCI, Linux, Windows, Android Hosted Infineon (Cypress) CYW20704 A2 Internal GPIO, GCI, I2S, PCM, USB 2402 MHz 2480 MHz Internal Multilayer Ceramic 2.2 mm 8.5 mm 12 mm Module
Product Type Technology OS/Software System Architecture Chipset (Wireless) Antenna Type Logical Interfaces Frequency Range (Min) Frequency Range (Max) Antenna Options Dimension (Height - mm) Dimension (Length - mm) Dimension (Width - mm) Type
BT850-ST Embedded Module Blutooth 5.0, Dual Mode (Classic + BLE) HCI, Linux, Windows, Android Hosted Infineon (Cypress) CYW20704 A2 External GPIO, GCI, I2S, PCM, USB 2402 MHz 2480 MHz External SMT Pad 1.9 mm 8.5 mm 13 mm Module
Product Type Technology OS/Software System Architecture Chipset (Wireless) Antenna Type Logical Interfaces Frequency Range (Min) Frequency Range (Max) Dimension (Height - mm) Dimension (Length - mm) Dimension (Width - mm) Type
BT851 USB Adapter Blutooth 5.0, Dual Mode (Classic + BLE) HCI, Linux, Windows, Android Hosted Infineon (Cypress) CYW20704 A2 Internal GPIO, GCI, I2S, PCM, USB 2402 MHz 2480 MHz 11 mm 43 mm 16 mm USB Pluggable
Product Type Technology OS/Software System Architecture Chipset (Wireless) Antenna Type Logical Interfaces Frequency Range (Min) Frequency Range (Max) Type
DVK-BT-850-SA Development Kit Blutooth 5.0, Dual Mode (Classic + BLE) HCI, Linux, Windows, Android Hosted Infineon (Cypress) CYW20704 A2 Internal GPIO, GCI, I2S, PCM, USB 2402 MHz 2480 MHz Development Kit
Product Type Technology OS/Software System Architecture Chipset (Wireless) Antenna Type Logical Interfaces Frequency Range (Min) Frequency Range (Max) Type
DVK-BT-850-ST Development Kit Blutooth 5.0, Dual Mode (Classic + BLE) HCI, Linux, Windows, Android Hosted Infineon (Cypress) CYW20704 A2 External GPIO, GCI, I2S, PCM, USB 2402 MHz 2480 MHz Development Kit

Photo Gallery

BT850-SA

BT850-ST

BT851

Certified Antennas

  • mFlexPIFA Antenna

    001-0030

    mFlexPIFA Flexible Adhesive-Backed PIFA Internal Antenna

    FlexPIFA antenna for metal mounting with minimal detuning. 2.4 GHz and dual-band 2.4/5.5 GHz with 2 dBi of gain. 

    Learn More
  • FlexPIFA and FlexPIFA 6E

    001-0014

    FlexPIFA / FlexPIFA 6E Flexible Adhesive-Backed PIFA Internal Antennas

    001-0014: FlexPIFA antenna, 2.4 GHZ 

    Industry-first, flexible, planar inverted-F antennas for curved surfaces.

    2.5-3 dBi gain.

    Available in 2.4 GHz, dual-band 2.4/5 GHz and Wi-Fi 6E 2.4/5/6 GHz.

    Learn More
  • Nano Blue Series - Bluetooth Internal

    MAF94045

    NanoBlue Series Bluetooth Internal Antenna

    2.4 GHz planar antenna with 2 dBi of Gain and an integrated ground plane for ease of integration.

    Learn More

Become a Laird Connectivity Customer and Gain Exclusive Access to Our Design Services Team

  • Antenna Scans
  • Antenna selection and placement
  • Custom antenna design
  • Worldwide EMC testing / certifications
  • Embedded RF hardware / firmware design
  • Cloud architecture and integration
  • Mobile application development
  • Product & Industrial Design

Talk to an Expert

Documentation

Name Part Type Last Updated
Product Brief - BT850 Series All Product Brief 10/11/2021
Datasheet - BT85x Series All Datasheet 02/15/2021
Application Note - Guidelines for Replacing Antennas v1.0 All Application Note 01/17/2019
BT8x0 PCB RF Design v1 0.pdf All Application Note 01/17/2019
Using the BT85x with Linux and Windows v1 0.pdf All Application Note 01/17/2019
UART HCI Bluetooth Module for Linux v1 0.pdf All Application Note 01/17/2019
HCI Bluetooth Module SPP Connection on Linux v1 0.pdf All Application Note 01/17/2019
RoHS 3 - Bluetooth All Certification 01/04/2022
3D Models - BT8x0-SA All Documentation 11/03/2020
3D Models - BT8x0-ST All Documentation 11/03/2020
PCN 10B-2018 All Documentation 05/20/2019
FCC Certifications - BT850-BT860 All Certification 10/06/2020
ISED (Canada) Certifications - BT850-BT860 All Certification 10/06/2020
EU Certifications - BT850/BT860 - 2020 All Certification 10/06/2020
Japan Certifications - BT850-BT860 All Certification 10/06/2020
KC Certifications - BT850-BT860 All Certification 10/06/2020
AS/NZS Certifications - BT850-BT860 All Certification 10/06/2020
AS/NZS Certifications - BT851 All Certification 10/06/2020
FCC Certifications - BT851 All Certification 10/06/2020
EU Certifications - BT851 - 2020 All Certification 10/20/2020
ISED (Canada) Certifications - BT851 All Certification 10/06/2020
Regulatory Information - BT850/BT851/BT860 All Certification 09/08/2021
Release Notes - Engineering Releases - Jan 2021 All Documentation 04/20/2021
ISED ICES-003 Issue 7 Declaration of Compliance All Certification 05/18/2021
PCN 8D-2021 - BT850/860 All Documentation 09/01/2021
Application Note - BT 5.x Feature Comparison for Laird Connectivity Bluetooth Modules All Documentation 02/24/2022
Schematic - DVK-BT850-Sx DVK-BT-850-SA Documentation 11/03/2020
Datasheet - DVK-BT85x Development Board DVK-BT-850-SA Datasheet 11/03/2020
Schematic - DVK-BT850-Sx DVK-BT-850-ST Documentation 11/03/2020
Datasheet - DVK-BT85x Development Board DVK-BT-850-ST Datasheet 11/03/2020

FAQ

Can I use a BT850/860 in the place of an existing BT800/830?

Yes, the following modules share the same pin layout:

BT800 --> BT850
BT830 --> BT860

There are some No Connect (NC) pins on the BT850/860

Is it safe to run a Laird Connectivity Bluetooth module through a PCBA wash cycle?

In general, cleaning the populated modules is strongly discouraged. Residuals under the module cannot be easily removed with any cleaning process. 

  • Cleaning with water can lead to capillary effects where water is absorbed into the gap between the host board and the module. The combination of soldering flux residuals and encapsulated water could lead to short circuits between neighboring pads. Water could also damage any stickers or labels.
  • Cleaning with alcohol or a similar organic solvent will likely flood soldering flux residuals into the RF shield, which is not accessible for post-washing inspection. The solvent could also damage any stickers or labels.
  • Ultrasonic cleaning could damage the module permanently.

However, if water washing is required you will need to use deionized water. We do not recommend chemical cleaning and cannot guarantee it will not damage the modules. If you MUST clean PCB with chemicals it is recommended that you test on one board and then confirm the module still works after the process, prior to adding it to production, while understanding the above affects washing the populated PCBs can have on the module.

The BT850, BT851 and BT860 are listed as Bluetooth 5 modules. What Bluetooth 5 features do they support?

The BT850, BT851 and BT860 are Bluetooth 5 qualified modules. However, these modules do not support any Bluetooth 5 features.
Per the Bluetooth SIG FAQ, "there are no mandatory features that must be claimed to use the Bluetooth 5.0 specification. However, manufacturers are required to implement all interoperability improvements and errata applied to Bluetooth 5 in order to comply with the specification".

Does the BT850 support coexistence?

Does the BT850 support coexistence?

yes. The BT850 supports the proprietary Cypress Global Coexistence Interface (GCI) which is a two-wire interface.
details can be found in the BT850 datasheet Datasheet - BT85x Series | Laird Connectivity

Contact Laird support if additional coexistence schemes are required.

Is a licence required to use the LC3 audio codec?

Use of the LC3 codec is included in the Bluetooth product licence when you qualify your product. No additional licence fees are required.

What is the maximum number of BLE connections that can be achieved with the BT85x or BT860?

The Cypress CYW20704 A2 chipset, which the BT85x and the BT860 is based on, theoretically supports up to 127 Bluetooth LE connections. However, because the BT860 is an HCI module it is dependent on the Bluetooth stack running on the host therefore, the number of connections will depend on what the host CPU and memory capacity can support.

Additionally, as the number of connections increases, the throughput per each connection will decrease and the processing and memory requirements will increase, which can lead to increased latency. So while 127 is the theoretical limit the actual limit in practical use case would be less than that.

Does the BT851 have the Bluetooth stack on board?

The BT851 is an HCI device and does not have the Bluetooth stack on board, and as such it relies on the host's stack. The BT851 should be recognized by the operating system as a Generic Bluetooth Adapter, not as a COM port.

How can I connect a Bluetooth Low Energy Device to a PC?

Bluetooth Low Energy uses Services as opposed to the set of standardized profiles that exists for Classic Bluetooth. While some Bluetooth Low Energy services have been standardized by the Bluetooth SIG, the development of custom services is allowed to meet custom application requirements.
 
Because Bluetooth Low Energy uses a completely different protocol than Classic Bluetooth and supports custom services, Bluetooth Low Energy devices cannot connect to a computer through the typical Bluetooth configuration of a computer. Therefore, connecting to a PC requires writing and running a Bluetooth Low Energy Central Role/Client application to collect the data sent from the Bluetooth Low Energy peripheral modules. Application development for PCs and Mobile devices is outside the scope of our support. Alternatively, a BL654 USB dongle could be used as a BLE Central Role device, to collect the BLE data and pass it to the PC over a COM Port. However, you would still need an application to view and process the data received over that COM Port.
 
We generally recommend customers who are new to Bluetooth Low Energy obtain a copy of Getting Started with Bluetooth Low Energy to help them understand the Bluetooth Low Energy protocol and the GATT table. There are also many resources available online which explain this. 

When Bluetooth Low Energy was first introduced and we launched our BL6xx product line (predecessors to the BL65x series) we produced the BL600 and BL620 smartBASIC Application Walkthrough document, which provides an overview of how Bluetooth Low Energy works and how a GATT table is constructed. 

Do I still have to list/qualify my product with the BT SIG even if I don't use the BT logo?

Yes, you need to qualify/list any product that uses BT SIG intellectual property, even if you do not use the logo or require interoperability with other BT devices. see here for more details. Qualify Your Product | Bluetooth® Technology Website

 

Why are multiple EMPTY_PDU are being sent from the Master per connection interval?

The communications protocol for Bluetooth is a ping pong type style, so every connection event begins with the Master sending the slave a packet and the Slave then responds to that packet with any data it may have. Therefore, when the Master has no data to transmit it will send an EMPTY_PDU to the Server and the Server, if it has data to send, will send back the data in response. You can see this readily where there is no data transmissions, the Master and Slave ping pong EMPTY_PDU’s back and forth on every connection event, if Slave Latency was incorporated then during these periods of no data transmissions you would see Master send EMPTY_PDU and no response from Slave because it has no data to send and was allowed to skip the connection event because of it.
 

Is there a way to extend the shelf life of Laird modules?? If the shelf life cannot be extended in any way, what are the consequences of using modules after shelf life?

The shelf life statements are essentially to prevent mishandling of the product and not storing it properly. If the modules are still sealed in the package, stored at the proper temperature and have not been exposed to moisture they should be fine. However, when working with modules beyond their shelf life you MUST bake the modules before populating the them to your board. Failure to bake the modules could result in the yield rate dropping down lower than expectation due to popcorn or de-lamination on the modules. It is recommended that you follow IPC/JEDEC J-STD-033 which is the general standard for the handling, packing, shipping and use of moisture/reflow sensitive surface mount devices.

Our main concern is around the castellation/pads which solder the module to the board. It is imperative those pads do not get tarnished, as this would cause soldering issues. Humidity can affect solderability as well, as if there is any excess moisture in the solder on the module, during reflow of the module to the board, steam balls can essentially explode the solder and sometimes result in an open circuit (or possibly a short circuit).

As long as all of the moisture handling and temperature guidelines are being followed you will likely have no issues. It is further recommended that when you do the build with modules that have exceeded their shelf life that you start with a handful to perform a test run and do a final test to make sure all is working as expected. As long as there are no issues with the initial test run we would expect that you will not experience any problems.

What factors influence the actual TX rate of the controller?

The actual TX rate is influenced by the PDU and MTU sizes along with the Connection Intervals and Slave Latency.

What is the Capacitor needed on BT850 nRESET line to prevent the low power glitch.

In order to prevent a low power glitch that can cause EEPROM corruption (no field fix for this state) in the BT850/ BT860, a 0.1uF capacitor should be placed on the nRESET line of the radio if the nRESET line is connected to something externally.
If the nRESET line is to be left NC (not connected) then the capacitor is not needed.