diff --git a/cpu/stm32f4/periph/adc.c b/cpu/stm32f4/periph/adc.c
index 1ee863bc95..410cf36767 100644
--- a/cpu/stm32f4/periph/adc.c
+++ b/cpu/stm32f4/periph/adc.c
@@ -110,8 +110,6 @@ int adc_sample(adc_t line, adc_res_t res)
     /* lock and power on the ADC device  */
     prep(line);
 
-    /* wait for any ongoing conversions to finish */
-    while (dev(line)->SR & ADC_SR_STRT) {}
     /* set resolution and conversion channel */
     dev(line)->CR1 = res;
     dev(line)->SQR3 = adc_config[line].chan;
@@ -120,7 +118,6 @@ int adc_sample(adc_t line, adc_res_t res)
     while (!(dev(line)->SR & ADC_SR_EOC)) {}
     /* finally read sample and reset the STRT bit in the status register */
     sample = (int)dev(line)->DR;
-    dev(line)->SR &= ~ADC_SR_STRT;
 
     /* power off and unlock device again */
     done(line);