diff --git a/Examples/FFT_03/FFT_03.ino b/Examples/FFT_03/FFT_03.ino
index 868c8be..30d5a7a 100644
--- a/Examples/FFT_03/FFT_03.ino
+++ b/Examples/FFT_03/FFT_03.ino
@@ -59,7 +59,7 @@ void loop()
 
       vReal[i] = analogRead(CHANNEL);
       vImag[i] = 0;
-      while(micros() < (microseconds + sampling_period_us)){
+      while(micros() - microseconds < sampling_period_us){
         //empty loop
       }
   }