> For the complete documentation index, see [llms.txt](https://wiki.vdbx.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wiki.vdbx.io/pcbs/csr8635-adapter.md).

# CSR8635 Adapter

***

### description: A breakout board for a CSR8635 development module with pin labels.

## CSR8635 Adapter

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The following is just a replication of the Tindie listing.
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Note: There are three main variants of these boards with different pin layouts:

1. Commonly listed as BTM-835B - this board has pins on all sides and requires an external antenna. It is generally a board with blue solder mask.
2. Commonly listed as BTM835 - this board generally has it's chip angled at 45° and has an equal amount of pins on both of the long sides. This one generally has a blue solder mask.
3. **Commonly listed as BC8635 -** Usually has green solder mask and the two long sides have 14 and 15 pins respectively.

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TODO: Add picture of modules for comparison
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AliExpress is my go-to for procuring them. Here are links to a couple:

<http://s.aliexpress.com/VfaueAnM>

<http://s.aliexpress.com/ruANJr6B>

### **Why did you make it?**

I am working on building a Bluetooth audio headset but didn't realize how small the pins on these modules are. For prototyping my device, I wanted to be able to use this board on a breadboard and have a visual reference to the pinouts.

### **What makes it special?**

These Bluetooth audio boards are super cheap and I'd love to see more people able to prototype with them. Look out for my headset project coming in a couple months.

### Design Files

Available on OSHW Lab for EasyEDA

<https://oshwlab.com/clomads/CSR8635_Breakout-72f90a02e918496186b20209678dd9dc>