High sleep current consumption in SED Thread+BLE multiprotocol example

Question

There is an issue in SDK for Thread & Zigbee 4.1.0 release. It does not appear in previous releases. The problem manifests itself as higher current consumption, as shown in below image: 
 
 The problem occurs when all the following is true: 
 
 nrf52840 device utilizes nrf_security libraries (nrf_security is used by default on nrf52840, except for Keil compiler). 
 SoftDevice is present (every multiprotocol example). 
 Processor is put to sleep by calling sd_app_evt_wait(). This is done for every Sleepy End Device (SED) by calling thread_sleep() in the main loop.

Jørgen Holmefjord · Accepted Answer

The root cause of this issue is pending CryptoCell interrupt in the NVIC register that prevents the system from sleeping. 
 There is a workaround for the issue. It requires placing the following code before the sd_app_evt_wait() call: 
 NVIC_ClearPendingIRQ(CRYPTOCELL_IRQn); 
 This line will clear the pending CryptoCell interrupt and allow the system to go to sleep mode. 
 Current consumption after adding the workaround is shown in below image:

High sleep current consumption in SED Thread+BLE multiprotocol example

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