Achieved max throughput of NRF5340 with iPhone is 520kbps.

RE: Achieved max throughput of NRF5340 with iPhone is 520kbps.

Rana Roy — Fri, 20 Jun 2025 14:33:40 GMT

Got it. Thank you Amanda Hsieh !

RE: Achieved max throughput of NRF5340 with iPhone is 520kbps.

Amanda Hsieh — Fri, 20 Jun 2025 13:18:51 GMT

As I explained in the previous post, the limitation is on iOS, which limits the number of BLE packets per connection event. The best throughput we’ve gotten is around 500–600 kbps.

RE: Achieved max throughput of NRF5340 with iPhone is 520kbps.

Rana Roy — Thu, 19 Jun 2025 11:59:00 GMT

Hi Amanda,

Thank you for support. I am getting 607 kbps maximum with your configurations. So, this is quite good as compared to the previous performance. But theoretically, the NRF5340 chip is capable of reaching somewhere around 1.2 to 1.4 Mbps. So, am I missing out on anything to achieve this speed?

RE: Achieved max throughput of NRF5340 with iPhone is 520kbps.

Amanda Hsieh — Tue, 17 Jun 2025 17:50:53 GMT

I use iPad air (ios 18.5). Here is my test project devzone.nordicsemi.com/.../throughput_5F00_test.7z.

RE: Achieved max throughput of NRF5340 with iPhone is 520kbps.

Rana Roy — Tue, 17 Jun 2025 17:08:06 GMT

Wow, it's really a great result!

Yes, I updated in both the conf files. I'm using iPhone 13 and iPad mini with iOS version 18.5. Could you please tell me which Apple device you are using?

RE: Achieved max throughput of NRF5340 with iPhone is 520kbps.

Amanda Hsieh — Tue, 17 Jun 2025 16:56:12 GMT

Hi,

Do you update the MTU 247 and data length 251 both in prj.conf and hci_ipc.conf?

I got 637 to 662 kbsp with your uploaded project.

-Amanda H.

RE: Achieved max throughput of NRF5340 with iPhone is 520kbps.

Rana Roy — Tue, 17 Jun 2025 13:06:31 GMT

Hi Amanda Hsieh , thank you so much for confirming!
So, you mean to say that our configurations of the MTU size and other buffers are at the best?
Because, when we tried changing these values to MTU 247 and data length 251, our throughput even reduced to the range of 180 to 220kbps.

RE: Achieved max throughput of NRF5340 with iPhone is 520kbps.

Amanda Hsieh — Tue, 17 Jun 2025 13:01:20 GMT

Hi,

iOS limits the number of BLE packets per connection event. The best throughput we’ve gotten is around 500–600 kbps.

Regards,
Amanda H.

RE: Achieved max throughput of NRF5340 with iPhone is 520kbps.

Rana Roy — Tue, 17 Jun 2025 06:11:43 GMT

Hi khelmutlord , thank you for quick response. The configurations are as follows:
CONFIG_BT_BUF_ACL_TX_SIZE=189
CONFIG_BT_BUF_ACL_RX_SIZE=189
CONFIG_BT_L2CAP_TX_MTU=185
CONFIG_BT_CTLR_DATA_LENGTH_MAX=189

I have attached the example code in the query, for more information.

RE: Achieved max throughput of NRF5340 with iPhone is 520kbps.

khelmutlord — Mon, 16 Jun 2025 16:23:50 GMT

Can you confirm what your MTU is set to? I believe that the iOS max is 247 bytes.
https://github.com/nrfconnect/sdk-zephyr/tree/main/samples/bluetooth/mtu_update/peripheral

Thanks,

Helmut Lord