diff --git a/Src/AdcFlagchip.c b/Src/AdcFlagchip.c
index 846ad17..66dc0cd 100644
--- a/Src/AdcFlagchip.c
+++ b/Src/AdcFlagchip.c
@@ -55,7 +55,7 @@ void ADC_Initial(
     env->s_tAdcInitCfg.eClockDivider = ADC_CLOCK_DIV_1;             //!< Adc clock divided by 1
     env->s_tAdcInitCfg.eSequenceMode = ADC_SEQMODE_SINGLE;          //!< Single sequence mode
     env->s_tAdcInitCfg.eOverrunMode = ADC_OVERRUN_MODE_PRESERVE;   //!< When overrun occurred, the old conversion data are preserved
-    env->s_tAdcInitCfg.eVoltageRef = ADC_REF_EXTERNAL;          //!< Use internal reference
+    env->s_tAdcInitCfg.eVoltageRef = ADC_REF_INTERNAL;          //!< Use internal reference
     env->s_tAdcInitCfg.bHwAvgEnable = false;                     //!< Disable averaging functionality
     env->s_tAdcInitCfg.eHwAverage = ADC_AVERAGE_32;             //!< Selection for number of samples used for averaging
     env->s_tAdcInitCfg.aSampleTimes[0] = 4U;