diff --git a/include/libopencm3/efm32/common/burtc_common.h b/include/libopencm3/efm32/common/burtc_common.h
index 73f78e1c..e2202a15 100644
--- a/include/libopencm3/efm32/common/burtc_common.h
+++ b/include/libopencm3/efm32/common/burtc_common.h
@@ -1,3 +1,5 @@
+/** @addtogroup burtc_defines
+ */
 /*
  * This file is part of the libopencm3 project.
  *
@@ -17,12 +19,13 @@
  * along with this library.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#ifndef LIBOPENCM3_EFM32_BURTC_H
-#define LIBOPENCM3_EFM32_BURTC_H
+#pragma once
 
 #include <libopencm3/efm32/memorymap.h>
 #include <libopencm3/cm3/common.h>
 
+/**@{*/
+
 #define BURTC_CTRL	MMIO32(BURTC_BASE + 0x000)
 #define BURTC_LPMODE	MMIO32(BURTC_BASE + 0x004)
 #define BURTC_CNT	MMIO32(BURTC_BASE + 0x008)
@@ -166,5 +169,5 @@
 #define BURTC_SYNCBUSY_COMP0		(1 << 1)
 #define BURTC_SYNCBUSY_LPMODE		(1 << 0)
 
-#endif
+/**@}*/
 
diff --git a/include/libopencm3/efm32/ezr32wg/burtc.h b/include/libopencm3/efm32/ezr32wg/burtc.h
index b96789d2..3f5c55a5 100644
--- a/include/libopencm3/efm32/ezr32wg/burtc.h
+++ b/include/libopencm3/efm32/ezr32wg/burtc.h
@@ -1,3 +1,11 @@
+/** @defgroup burtc_defines BURTC Defines
+ *
+ * @brief <b>Defined Constants and Types for the Backup RTC</b>
+ *
+ * @ingroup EZR32WG_defines
+ *
+ * LGPL License Terms @ref lgpl_license
+ */
 /*
  * This file is part of the libopencm3 project.
  *
@@ -17,9 +25,6 @@
  * along with this library.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#ifndef LIBOPENCM3_EFM32_EZR32WG_BURTC_H
-#define LIBOPENCM3_EFM32_EZR32WG_BURTC_H
+#pragma once
 
 #include <libopencm3/efm32/common/burtc_common.h>
-
-#endif
diff --git a/include/libopencm3/efm32/lg/burtc.h b/include/libopencm3/efm32/lg/burtc.h
index 132c3d02..fa580335 100644
--- a/include/libopencm3/efm32/lg/burtc.h
+++ b/include/libopencm3/efm32/lg/burtc.h
@@ -1,3 +1,11 @@
+/** @defgroup burtc_defines BURTC Defines
+ *
+ * @brief <b>Defined Constants and Types for the Backup RTC</b>
+ *
+ * @ingroup EFM32LG_defines
+ *
+ * LGPL License Terms @ref lgpl_license
+ */
 /*
  * This file is part of the libopencm3 project.
  *
@@ -17,9 +25,6 @@
  * along with this library.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#ifndef LIBOPENCM3_EFM32_LG_BURTC_H
-#define LIBOPENCM3_EFM32_LG_BURTC_H
+#pragma once
 
 #include <libopencm3/efm32/common/burtc_common.h>
-
-#endif
diff --git a/include/libopencm3/efm32/wg/burtc.h b/include/libopencm3/efm32/wg/burtc.h
index 9246ea03..28e605ad 100644
--- a/include/libopencm3/efm32/wg/burtc.h
+++ b/include/libopencm3/efm32/wg/burtc.h
@@ -1,3 +1,11 @@
+/** @defgroup burtc_defines BURTC Defines
+ *
+ * @brief <b>Defined Constants and Types for the Backup RTC</b>
+ *
+ * @ingroup EFM32WG_defines
+ *
+ * LGPL License Terms @ref lgpl_license
+ */
 /*
  * This file is part of the libopencm3 project.
  *
@@ -17,9 +25,6 @@
  * along with this library.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#ifndef LIBOPENCM3_EFM32_WG_BURTC_H
-#define LIBOPENCM3_EFM32_WG_BURTC_H
+#pragma once
 
 #include <libopencm3/efm32/common/burtc_common.h>
-
-#endif
diff --git a/lib/efm32/common/burtc_common.c b/lib/efm32/common/burtc_common.c
new file mode 100644
index 00000000..e909f8cd
--- /dev/null
+++ b/lib/efm32/common/burtc_common.c
@@ -0,0 +1,15 @@
+/** @addtogroup burtc_file BURTC peripheral API
+ * @ingroup peripheral_apis
+ * @brief Backup RTC helper functions.
+ *
+ * <b>NO</b> helper functions exist. Only header definitions are available.
+ * Delete these lines if/when you add actual helper APIs.
+ * @copyright See @ref lgpl_license
+ */
+
+#include <libopencm3/efm32/burtc.h>
+
+/**@{*/
+
+/**@}*/
+
diff --git a/lib/efm32/ezr32wg/Makefile b/lib/efm32/ezr32wg/Makefile
index e7fd6bdc..44763d7e 100644
--- a/lib/efm32/ezr32wg/Makefile
+++ b/lib/efm32/ezr32wg/Makefile
@@ -39,6 +39,7 @@ ARFLAGS		= rcs
 
 OBJS += acmp_common.o
 OBJS += adc_common.o
+OBJS += burtc_common.o
 OBJS += cmu_common.o
 OBJS += dac_common.o
 OBJS += dma_common.o
diff --git a/lib/efm32/lg/Makefile b/lib/efm32/lg/Makefile
index 7c6eb1a1..94ca814c 100644
--- a/lib/efm32/lg/Makefile
+++ b/lib/efm32/lg/Makefile
@@ -39,6 +39,7 @@ ARFLAGS		= rcs
 
 OBJS += acmp_common.o
 OBJS += adc_common.o
+OBJS += burtc_common.o
 OBJS += cmu_common.o
 OBJS += dac_common.o
 OBJS += dma_common.o
diff --git a/lib/efm32/wg/Makefile b/lib/efm32/wg/Makefile
index 17c91eb9..f2ca009f 100644
--- a/lib/efm32/wg/Makefile
+++ b/lib/efm32/wg/Makefile
@@ -39,6 +39,7 @@ ARFLAGS		= rcs
 
 OBJS += acmp_common.o
 OBJS += adc_common.o
+OBJS += burtc_common.o
 OBJS += cmu_common.o
 OBJS += dac_common.o
 OBJS += dma_common.o