diff --git a/boards/nucleo-f207zg/include/periph_conf.h b/boards/nucleo-f207zg/include/periph_conf.h
index b5dfe7be81..6504e62c97 100644
--- a/boards/nucleo-f207zg/include/periph_conf.h
+++ b/boards/nucleo-f207zg/include/periph_conf.h
@@ -223,11 +223,12 @@ static const spi_conf_t spi_config[] = {
  * PIN, device (ADCx), channel
  * @{
  */
-#define ADC_CONFIG {              \
-    {GPIO_PIN(PORT_A, 3), 0, 3},  \
-    {GPIO_PIN(PORT_C, 0), 1, 0}  \
-}
-#define ADC_NUMOF          (2)
+static const adc_conf_t adc_config[] = {
+    {GPIO_PIN(PORT_A, 3), 0, 3},
+    {GPIO_PIN(PORT_C, 0), 1, 0}
+};
+
+#define ADC_NUMOF           ARRAY_SIZE(adc_config)
 /** @} */
 
 /**