BlueNRG-MS not working properly

[manuel_EncoreLab]

Hello everyone,

I'm currently developing a custom PCB with the reference design of the STEVAL-WESU1 and I'm having problems making the BLE work. I can communicate with the chip and it answers correctly, but when told to generate the generate the service and advertise I can't find it with my mobile. I have tested the same code with the STEVAL-WESU1 and it worked (I set it up to have the same pinout, so the code is literally the same). I would like to receive some opinions on what can be making the BLE not work, as I'm running out of ideas of what to check. Also, under the Balun (BALF-NRG-01D3) I did not remove the GND plane, being this different as the reference designs of the balun. The antenna trace is wider and has less spacing with the GND plane, as you can see in the image. I kindly ask for help to anyone who can suggest anything to check in order to try to get this design working.

Thanks in advance for your time.

Regards,

Manuel

[Mselv]

did you initalised the internal bus which is used for communicating with the host microcontroller

in the discovery kit , usually the modules and microcontrollers are connected by spi.

[manuel_EncoreLab]

Yes, we already did, we do communicate effectivelly with the BlueNRG as we get the appropriate returns and we get the chip info (vendor, in this case 0x30 = 48 = ST; HW version and the firmware stack version). We do see a difference in current consumptions, with the same program, between the STEVAL-WESU1 and our design. We do see the current peaks every second when advertising with the STEVAL-WESU1 but we don't see them with our design, as you can see in the attached pics (program was: reset the BlueNRG for 1 second, initialize it and configure it to advertise every second, then wait 5 seconds, then repeat). The current measurement was made at the battery supply, with every other cable disconected, measuring a 5 ohm resistance soldered into the BAT- cable of the battery, and reading with the oscilloscope at both sides of the battery