diff --git a/ChangeLog b/ChangeLog
index 29acca935..fd5194375 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -6,6 +6,8 @@ Changes
    * Removed mutexes from ECP hardware accelerator code. Now all hardware
      accelerator code in the library leaves concurrency handling to the
      platform. Reported by Steven Cooreman. #863
+   * Define the macro MBEDTLS_AES_ROM_TABLES in the configuration file
+     config-no-entropy.h to reduce the RAM footprint.
 
 = mbed TLS 2.5.1 released 2017-06-21