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jet_hao
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BLE Performance difference

Hi there,

We have two reference systems that are logically identical, but the PCB layout is different. Let's call it board A and board B. Board A is a small Form Factor while Board B is a larger one. In real test, the performance (BLE throughput) is drastically different. Board A is at least 2X faster than Board B with exact same firmware. I know the crystal between the two boards are different but both are within requirement. What are the other possibilities to cause different performance? Antenna design, power ground of PCB, or something else? I did notice that the slower one has fewer beacon than the other. Is it due to Bit Error Rate? Do you have a recommended tool do find out bit error rate?

Thanks
Hao

Device:
MT_dialog
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Hi jet_hao,

Hi jet_hao,

Besides the reasons you are mentioning (antenna is a major parameter) the air traffic can be an important issue, are those devices were tested at the same enviroment ? are they tested at the same time also ? are they connected to the same central ? and the central had choosen the same connection intervals for both of those devices ? I dont get the "fewer beacon" you mean you could track less packets of that device over the air ?

Thanks MT_dialog

jet_hao
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Hi MT_dialog,

Hi MT_dialog,

It turns out that the issue is due to a insufficient bypass capacitor. Big voltage drop put the system into unstable state. Thanks for your help.

MT_dialog
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Hi jet_hao,

Hi jet_hao,

Thanks for indicating.

Best Regards MT_dialog