diff --git a/src/drivers/kinetis/adc/adc.cpp b/src/drivers/kinetis/adc/adc.cpp
index d4b27adb1e..ec767c9322 100644
--- a/src/drivers/kinetis/adc/adc.cpp
+++ b/src/drivers/kinetis/adc/adc.cpp
@@ -376,7 +376,7 @@ ADC::update_system_power(hrt_abstime now)
 
 		if (_samples[i].am_channel == ADC_5V_RAIL_SENSE) {
 			// it is 2:1 scaled
-			system_power.voltage5V_v = _samples[i].am_data * (6.6f / 4096);
+			system_power.voltage5V_v = _samples[i].am_data * (6.6f / 4096.0f);
 		}
 	}
 
diff --git a/src/drivers/samv7/adc/adc.cpp b/src/drivers/samv7/adc/adc.cpp
index 6e418e07b2..38373bf4c1 100644
--- a/src/drivers/samv7/adc/adc.cpp
+++ b/src/drivers/samv7/adc/adc.cpp
@@ -324,7 +324,7 @@ ADC::update_system_power(void)
 	for (unsigned i = 0; i < _channel_count; i++) {
 		if (_samples[i].am_channel == 4) {
 			// it is 2:1 scaled
-			system_power.voltage5V_v = _samples[i].am_data * (6.6f / 4096);
+			system_power.voltage5V_v = _samples[i].am_data * (6.6f / 4096.0f);
 		}
 	}
 
diff --git a/src/drivers/stm32/adc/adc.cpp b/src/drivers/stm32/adc/adc.cpp
index 31819da96a..24a55a6c13 100644
--- a/src/drivers/stm32/adc/adc.cpp
+++ b/src/drivers/stm32/adc/adc.cpp
@@ -281,6 +281,7 @@ int board_adc_init()
 
 	return OK;
 }
+
 int
 ADC::init()
 {
@@ -401,7 +402,7 @@ ADC::update_system_power(hrt_abstime now)
 
 		if (_samples[i].am_channel == ADC_SCALED_V5_SENSE) {
 			// it is 2:1 scaled
-			system_power.voltage5V_v = _samples[i].am_data * (ADC_V5_V_FULL_SCALE / 4096);
+			system_power.voltage5V_v = _samples[i].am_data * (ADC_V5_V_FULL_SCALE / 4096.0f);
 			cnt--;
 
 		} else