Zigbee SDK Version 9.0 - Release Notes (Jan 22, 2026)#

Zigbee Version 9.0

Simplicity SDK Version 2025.12.0

Silicon Labs is the vendor of choice for OEMs developing Zigbee networking into their products. The Silicon Labs Zigbee platform is the most integrated, complete, and feature-rich Zigbee solution available.

Silicon Labs EmberZNet SDK contains Silicon Labs’ implementation of the Zigbee stack specification.

Click here for earlier releases.

Release Summary#

Key Features | API Changes | Bug Fixes | Chip Enablement

Key Features#

• Zigbee 4.0 compliance with BDB 3.1 and R23 support.

• Dynamic switching of Zigbee node type between router and sleepy end device.

• Inter-PAN messages filtering update.

• Software support for new Series 3 boards.

API Changes#

See Modified APIs.

Bug Fixes#

See Bug Fixes.

Chip Enablement#

SW support for two new boards: QFN40 5x5 Explorer Kit (BRD2719) and a Pro Kit consisting of a BRD4407A Radio Board (with 4 MB flash) packaged with a WPK. The IC OPN is SiMG301M104LIL for both products.

Key Features#

New Features | Enhancements | Removed Features | Deprecated Features

New Features#

Zigbee 4.0 compliance with BDB 3.1 and R23 support#

• This release is Zigbee 4.0 certification-ready, with BDB 3.1 and R23 features incorporated.

• BDB 3.1 builds upon and consumes the features of the revision 23 Zigbee PRO Core stack, which includes, but is not limited to, Dynamic Link Key (DLK) exchange, network commissioning with optional device interview, APS frame counter synchronization, and trust center swap out.

• BDB 3.1 support also brings in support for a rejoining algorithm for network recovery when TC connectivity is lost. The new BDB 3.1 Rejoin Algorithm component handles trust center connectivity loss and implements the BDB 3.1 rejoin algorithm to rejoin the network when needed. This component is only necessary for Zigbee 4.0 joining devices, such as routers and end devices.

• A new BDB 3.1 Trust Center Extension component has been added to perform necessary Zigbee 4.0 behavior for trust centers. This component handles auto-discovery of devices that join the network. The component will send binding requests to any end devices that support the Poll Control cluster, as mandated by the BDB specifications. This component is only necessary for Zigbee 4.0 trust centers or coordinators.

• Two new sample applications are provided to showcase this functionality. The Zigbee - Z4Light application is a dual role coordinator/router application that can either act as trust center to form a Zigbee 4.0 network, or it can act as a Zigbee 4.0 router joining device. The new Zigbee - Z4Switch application acts as receiver-on-when-idle end device that can join a Zigbee 4.0 network. Both of these applications consume the previously mentioned components which provide new Zigbee 4.0 functionality. Users are reminded that these sample applications are examples of showcasing features and that users should extend, test, and validate final applications for conformance to the standards.

• Zigbee 4.0 applications built using the Silicon Labs SDK automatically perform the Dynamic Link Key (DLK) procedure when joining. There are a number of new public APIs and callbacks that relate to the R23 joining flow of devices, which can be found in sl_zigbee_dlk_negotiation.h sl_zigbee_zdo_dlk_negotiation.h, sl_zigbee_dynamic_commissioning.h, and others.

• sl_zigbee_dynamic_commissioning.h, for example, exposes callbacks to alert the user application for when a joining device completes DLK and is sent the network key. A public API is available to control whether the device interview step should be conducted or skipped when devices try to join the network.

Dynamic switching of Zigbee node type between router and sleepy end device#

• This features allows an image to dynamically switch between a router and a sleepy end device at runtime.

• There are two APIs provided to have a router transition to a sleepy end device and vice-versa. Once transitioned, the device will issue a network rejoin followed by a Device Announce to alert the network of the role change.

• This feature is not to be confused with the multi-network feature, whereby an image can be configured with two device types operating on different networks (for that, see AN724).

Update Filtering of inter-PAN Messages#

• Updated filtering of inter-PAN message to support multiple filters matching regardless of whether ZLL or custom filters match. The matched filter value will be passed up to the application using sli_802154_stack_filter_match_message_handler().

• Previously, if a filter matched the stack-specified Zigbee Light Link (ZLL) or Green Power (GP) filter, the stack would consume the packet. With this update, the user application may configure a filter that is equivalent to the ZLL or GP filter and the user application will be alerted when a packet that matches the filter is received.

Software support for new Series 3 boards#

QFN40 5x5 Explorer Kit (BRD2719) and a Pro Kit consisting of a BRD4407A Radio Board (with 4 MB flash) packaged with a WPK.

Enhancements#

Code quality enhancements include reduced compiler warnings in all Zigbee sample aplications for various configurations.

Removed Features#

None.

Deprecated Features#

API Changes#

New APIs | Modified APIs | Removed APIs | Deprecated APIs

New APIs#

Modified APIs#

None.

Removed APIs#

None.

Deprecated APIs#

None.

Bug Fixes#

Chip Enablement#

Application Example Changes#

New Examples | Modified Examples | Removed Examples | Deprecated Examples

New Examples#

Modified Examples#

None.

Removed Examples#

None.

Deprecated Examples#

None.

Known Issues and Limitations#

Code example for Known Issue 1503910:

 // Set the user repack threshold
                static uint32_t user_repack_threshold = 1024;
                /***************************************************************************//**
                * Perform a user-triggered repack with a configurable threshold.
                *
                * This function sets the number of bytes (threshold) that must remain free
                * before a forced repack is triggered. It performs repack operations until
                * the threshold is satisfied or no further memory can be freed.
                ******************************************************************************/
                void nvm3_repack_with_threshold(void)
                {
                  sl_status_t sta;
                  nvm3_MemInfo_t memInfo;
                  size_t initMemInfo;  // Get available memory
                  if (nvm3_getMemInfo(nvm3_defaultHandle, &memInfo) != SL_STATUS_OK) {
                    printf("Get memory info failed at startup\r\n");
                    return;
                  }  // Set the repack headroom to user threshold
                  nvm3_defaultInit->repackHeadroom = user_repack_threshold;
                  sta = nvm3_open(nvm3_defaultHandle, nvm3_defaultInit);
                  if (sta != SL_STATUS_OK) {
                    printf("NVM3 re-open with increased headroom failed: %lu\r\n", sta);
                    return;
                  }
                  initMemInfo = memInfo.availableMemory;
                  int repack =0;
                  while (user_repack_threshold > memInfo.availableMemory) {
                    repack++;
                    sta = nvm3_repack(nvm3_defaultHandle);
                    if (sta != SL_STATUS_OK) {
                      printf("ERROR: NVM3 repack failed! Status: %lu\r\n", sta);
                      EFM_ASSERT(sta == SL_STATUS_OK);
                      break;
                    }
                    nvm3_getMemInfo(nvm3_defaultHandle, &memInfo);
                  }
                  return;
                }