Bluetooth LE SDK Controller Version 11.1.1 - Release Notes (Jul 29, 2026)#

Bluetooth LE Version 11.1.1

The Bluetooth SDK is an advanced Bluetooth 6.1-compliant stack that provides all of the core functionality along with multiple API to simplify development. The core functionality offers both standalone mode, allowing a developer to create and run their application directly on the SoC, and NCP mode, allowing for the use of an external host MCU.

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Release Summary#

Key Features | API Changes | Bug Fixes | Chip Enablement

Key Features#

Added in 11.1.1#

None.

Added in 11.1.0#

• Added support for Advertising Data Info (ADI) in Periodic Advertising and Periodic Advertising with Responses.

• Added Channel Map Update Indication support for the Periodic Advertising advertiser, enabling Adaptive Frequency Hopping with Periodic Advertising in congested RF environments.

• Improved Bluetooth LE power efficiency for advertising and peripheral connection use cases.

• Extended the Bluetooth LE CTE antenna switching pattern from 50 to 66 antenna IDs.

• Moved the selection of active or passive Adaptive Frequency Hopping (AFH) from the Bluetooth Low Energy Controller component to the AFH component.

API Changes#

Changed in 11.1.1#

None.

Changed in 11.1.0#

• Added the SL_BLUETOOTH_COMMON_BUFFER_MEMORY_SIZE configuration to the Bluetooth Low Energy Common component.

• Added SL_BT_CONTROLLER_RF_RX_PATH_GAIN_DECI_DB and SL_BT_CONTROLLER_RF_TX_PATH_GAIN_DECI_DB configurations to the Bluetooth Low Energy Common component.

• Removed SL_BT_HOST_ADAPTATION_RADIO_IRQ_PRIORITY and SL_BT_HOST_ADAPTATION_LINKLAYER_IRQ_PRIORITY. Use SL_BT_CONTROLLER_RADIO_IRQ_PRIORITY and SL_BT_CONTROLLER_LINKLAYER_IRQ_PRIORITY in the Bluetooth Low Energy Controller component instead.

• Deprecated SL_BT_CONFIG_BUFFER_SIZE, SL_BT_CONFIG_RF_PATH_GAIN_RX, and SL_BT_CONFIG_RF_PATH_GAIN_TX in the Bluetooth Core component, and SL_BT_CONTROLLER_BUFFER_MEMORY in the Bluetooth Low Energy Controller component.

Bug Fixes#

Fixed in 11.1.1#

• Connection Analyzer reliability improved: Received Signal Strength Indicator (RSSI) is now reported for every connection event, including cases where the peripheral does not respond.

• Fixed an issue in the Bluetooth LE controller related to TX power setting, where incorrect behavior happened if the minimum power was requested to be higher than the maximum power.

• Fixed an issue in the Bluetooth LE controller related to Channel Sounding, where repeatedly enabling and disabling the CS procedure could trigger a race condition causing subsequent subevents to be continuously aborted.

• Fixed an issue in the Bluetooth LE controller where a device synchronized to a PAwR advertiser would lose sync if the advertiser sent many connection requests in place of the sync packet.

• Fixed an issue where Bluetooth Channel Sounding, when configured with the minimum subevent length, could exceed the 32-subevents per procedure limit and cause processing errors.

• Fixed an issue in Bluetooth Channel Sounding where, when only one subevent fits per ACL connection event, the last two subevent results could be reported with the same ACL connection event index.

Fixed in 11.1.0#

• Fixed a Co-Processor Communication (CPC) issue where host reconnection to the BLE endpoint could fail after a client disconnect on multiprotocol applications.

• Fixed BLE Extended Advertising TX power handling. The controller now correctly interprets the Host Controller Interface (HCI) "no preference" TX power setting.

• Fixed an issue where the scanner could exceed the configured scan window while following extended advertisements, causing higher power consumption.

• Fixed an issue where the Bluetooth LE controller did not report support for LE Periodic Advertising in the link layer features.

• Corrected the RAIL window scheduler priority configuration naming, with no change to default behavior.

Chip Enablement#

None.

Key Features#

New Features | Enhancements | Removed Features | Deprecated Features

New Features#

Added in 11.1.1#

None.

Added in 11.1.0#

• Added support for ADI in Periodic Advertising and Periodic Advertising with Responses, improving interoperability with devices expecting this capability.

• Added Channel Map Update Indication support for the Periodic Advertising advertiser, enabling Adaptive Frequency Hopping with Periodic Advertising for improved reliability in congested or noisy RF environments.

Enhancements#

Added in 11.1.1#

None.

Added in 11.1.0#

• Improved Bluetooth LE power efficiency by optimizing Link Layer event handling for advertising and peripheral connection scenarios.

• Extended the Bluetooth LE CTE antenna switching pattern length from 50 to 66 antenna IDs, enabling longer AoA/AoD antenna patterns.

• Moved the selection of active or passive AFH from the Bluetooth Low Energy Controller component to the AFH component. Documentation was updated to clarify usage and selection.

Removed Features#

Removed in 11.1.1#

None.

Removed in 11.1.0#

• Removed the SL_BT_HOST_ADAPTATION_RADIO_IRQ_PRIORITY and SL_BT_HOST_ADAPTATION_LINKLAYER_IRQ_PRIORITY configurations. Use SL_BT_CONTROLLER_RADIO_IRQ_PRIORITY and SL_BT_CONTROLLER_LINKLAYER_IRQ_PRIORITY in the Bluetooth Low Energy Controller component instead.

Deprecated Features#

Deprecated in 11.1.1#

None.

Deprecated in 11.1.0#

• Deprecated the SL_BT_CONFIG_BUFFER_SIZE, SL_BT_CONFIG_RF_PATH_GAIN_RX, and SL_BT_CONFIG_RF_PATH_GAIN_TX configurations in the Bluetooth Core component, and the SL_BT_CONTROLLER_BUFFER_MEMORY configuration in the Bluetooth Low Energy Controller component. Replacement configurations are provided in the Bluetooth Low Energy Common component. Existing projects remain compatible in this release; migration is recommended ahead of removal planned for a future release.

API Changes#

New APIs | Modified APIs | Removed APIs | Deprecated APIs

New APIs#

Added in 11.1.1#

None.

Added in 11.1.0#

• Added the SL_BLUETOOTH_COMMON_BUFFER_MEMORY_SIZE configuration to the Bluetooth Low Energy Common component, enabling tuning of the Bluetooth LE Common buffer memory size. Defaults preserve previous behavior.

• Added the SL_BT_CONTROLLER_RF_RX_PATH_GAIN_DECI_DB and SL_BT_CONTROLLER_RF_TX_PATH_GAIN_DECI_DB configurations to the Bluetooth Low Energy Common component.

Modified APIs#

Modified in 11.1.1#

None.

Modified in 11.1.0#

None.

Removed APIs#

Removed in 11.1.1#

None.

Removed in 11.1.0#

• Removed SL_BT_HOST_ADAPTATION_RADIO_IRQ_PRIORITY and SL_BT_HOST_ADAPTATION_LINKLAYER_IRQ_PRIORITY. Use SL_BT_CONTROLLER_RADIO_IRQ_PRIORITY and SL_BT_CONTROLLER_LINKLAYER_IRQ_PRIORITY from the Bluetooth Low Energy Controller component.

Deprecated APIs#

Deprecated in 11.1.1#

None.

Deprecated in 11.1.0#

• Deprecated SL_BT_CONFIG_BUFFER_SIZE, SL_BT_CONFIG_RF_PATH_GAIN_RX, and SL_BT_CONFIG_RF_PATH_GAIN_TX in the Bluetooth Core component.

• Deprecated SL_BT_CONTROLLER_BUFFER_MEMORY in the Bluetooth Low Energy Controller component.

Bug Fixes#

Fixed in 11.1.1#

Fixed in 11.1.0#

Known Issues and Limitations#