diff --git a/arch/arm/src/stm32l4/stm32l4_tim.c b/arch/arm/src/stm32l4/stm32l4_tim.c
index d3bb3a55bda..0349482a480 100644
--- a/arch/arm/src/stm32l4/stm32l4_tim.c
+++ b/arch/arm/src/stm32l4/stm32l4_tim.c
@@ -1127,7 +1127,7 @@ static int stm32l4_tim_setchannel(FAR struct stm32l4_tim_dev_s *dev,
 
   /* Further we use range as 0..3; if channel=0 it will also overflow here */
 
-  if (--channel > 4)
+  if (--channel > 3)
     {
       return -EINVAL;
     }