diff --git a/targets/TARGET_STM/TARGET_STM32F1/TARGET_BLUEPILL_F103C8/PeripheralPins.c b/targets/TARGET_STM/TARGET_STM32F1/TARGET_BLUEPILL_F103C8/PeripheralPins.c
index b845ac6ec5..ca5fcf9134 100644
--- a/targets/TARGET_STM/TARGET_STM32F1/TARGET_BLUEPILL_F103C8/PeripheralPins.c
+++ b/targets/TARGET_STM/TARGET_STM32F1/TARGET_BLUEPILL_F103C8/PeripheralPins.c
@@ -56,6 +56,7 @@ const PinMap PinMap_ADC[] = {
     {PC_4, ADC_1, STM_PIN_DATA_EXT(STM_MODE_ANALOG, GPIO_NOPULL, 0, 14, 0)}, // ADC_IN14
     {PC_5, ADC_1, STM_PIN_DATA_EXT(STM_MODE_ANALOG, GPIO_NOPULL, 0, 15, 0)}, // ADC_IN15
     {ADC_TEMP, ADC_1, STM_PIN_DATA_EXT(STM_MODE_ANALOG, GPIO_NOPULL, 0, 16, 0)}, // ADC_IN16
+    {ADC_VREF, ADC_1, STM_PIN_DATA_EXT(STM_MODE_ANALOG, GPIO_NOPULL, 0, 17, 0)}, // ADC_IN17
     {NC,   NC,    0}
 };
 
diff --git a/targets/TARGET_STM/TARGET_STM32F1/TARGET_BLUEPILL_F103C8/PinNames.h b/targets/TARGET_STM/TARGET_STM32F1/TARGET_BLUEPILL_F103C8/PinNames.h
index 54e6b3c70a..a4253c997f 100644
--- a/targets/TARGET_STM/TARGET_STM32F1/TARGET_BLUEPILL_F103C8/PinNames.h
+++ b/targets/TARGET_STM/TARGET_STM32F1/TARGET_BLUEPILL_F103C8/PinNames.h
@@ -46,9 +46,9 @@ extern "C" {
                                                                        ((CHANNEL  & 0x1F) << 11) |\
                                                                        ((INVERTED & 0x01) << 16)))
 
-#define STM_PIN_MODE(X)   (((X) >> 0) & 0x0F)
-#define STM_PIN_PUPD(X)   (((X) >> 4) & 0x07)
-#define STM_PIN_AFNUM(X)  (((X) >> 7) & 0x0F)
+#define STM_PIN_MODE(X)     (((X) >>  0) & 0x0F)
+#define STM_PIN_PUPD(X)     (((X) >>  4) & 0x07)
+#define STM_PIN_AFNUM(X)    (((X) >>  7) & 0x0F)
 #define STM_PIN_CHANNEL(X)  (((X) >> 11) & 0x1F)
 #define STM_PIN_INVERTED(X) (((X) >> 16) & 0x01)
 
@@ -132,6 +132,7 @@ typedef enum {
 
     // ADC internal channels
     ADC_TEMP = 0xF0,
+    ADC_VREF = 0xF1,
 
     // PCB printout
     A0          = PA_0,
diff --git a/targets/TARGET_STM/TARGET_STM32F1/TARGET_DISCO_F100RB/PeripheralPins.c b/targets/TARGET_STM/TARGET_STM32F1/TARGET_DISCO_F100RB/PeripheralPins.c
index e368495573..38e2827c25 100644
--- a/targets/TARGET_STM/TARGET_STM32F1/TARGET_DISCO_F100RB/PeripheralPins.c
+++ b/targets/TARGET_STM/TARGET_STM32F1/TARGET_DISCO_F100RB/PeripheralPins.c
@@ -56,6 +56,7 @@ const PinMap PinMap_ADC[] = {
     {PC_4, ADC_1, STM_PIN_DATA_EXT(STM_MODE_ANALOG, GPIO_NOPULL, 0, 14, 0)}, // ADC_IN14
     {PC_5, ADC_1, STM_PIN_DATA_EXT(STM_MODE_ANALOG, GPIO_NOPULL, 0, 15, 0)}, // ADC_IN15
     {ADC_TEMP, ADC_1, STM_PIN_DATA_EXT(STM_MODE_ANALOG, GPIO_NOPULL, 0, 16, 0)}, // ADC_IN16
+    {ADC_VREF, ADC_1, STM_PIN_DATA_EXT(STM_MODE_ANALOG, GPIO_NOPULL, 0, 17, 0)}, // ADC_IN17
     {NC,   NC,    0}
 };
 
diff --git a/targets/TARGET_STM/TARGET_STM32F1/TARGET_DISCO_F100RB/PinNames.h b/targets/TARGET_STM/TARGET_STM32F1/TARGET_DISCO_F100RB/PinNames.h
index eaa0652a31..5cdac4ee4a 100644
--- a/targets/TARGET_STM/TARGET_STM32F1/TARGET_DISCO_F100RB/PinNames.h
+++ b/targets/TARGET_STM/TARGET_STM32F1/TARGET_DISCO_F100RB/PinNames.h
@@ -46,9 +46,9 @@ extern "C" {
                                                                        ((CHANNEL  & 0x1F) << 11) |\
                                                                        ((INVERTED & 0x01) << 16)))
 
-#define STM_PIN_MODE(X)   (((X) >> 0) & 0x0F)
-#define STM_PIN_PUPD(X)   (((X) >> 4) & 0x07)
-#define STM_PIN_AFNUM(X)  (((X) >> 7) & 0x0F)
+#define STM_PIN_MODE(X)     (((X) >>  0) & 0x0F)
+#define STM_PIN_PUPD(X)     (((X) >>  4) & 0x07)
+#define STM_PIN_AFNUM(X)    (((X) >>  7) & 0x0F)
 #define STM_PIN_CHANNEL(X)  (((X) >> 11) & 0x1F)
 #define STM_PIN_INVERTED(X) (((X) >> 16) & 0x01)
 
@@ -134,6 +134,7 @@ typedef enum {
 
     // ADC internal channels
     ADC_TEMP = 0xF0,
+    ADC_VREF = 0xF1,
 
     // Arduino connector namings
     PA0          = PA_0,
diff --git a/targets/TARGET_STM/TARGET_STM32F1/TARGET_NUCLEO_F103RB/PeripheralPins.c b/targets/TARGET_STM/TARGET_STM32F1/TARGET_NUCLEO_F103RB/PeripheralPins.c
index 36c7ee21ec..444cd36216 100644
--- a/targets/TARGET_STM/TARGET_STM32F1/TARGET_NUCLEO_F103RB/PeripheralPins.c
+++ b/targets/TARGET_STM/TARGET_STM32F1/TARGET_NUCLEO_F103RB/PeripheralPins.c
@@ -56,6 +56,7 @@ const PinMap PinMap_ADC[] = {
     {PC_4, ADC_1, STM_PIN_DATA_EXT(STM_MODE_ANALOG, GPIO_NOPULL, 0, 14, 0)}, // ADC_IN14
     {PC_5, ADC_1, STM_PIN_DATA_EXT(STM_MODE_ANALOG, GPIO_NOPULL, 0, 15, 0)}, // ADC_IN15
     {ADC_TEMP, ADC_1, STM_PIN_DATA_EXT(STM_MODE_ANALOG, GPIO_NOPULL, 0, 16, 0)}, // ADC_IN16
+    {ADC_VREF, ADC_1, STM_PIN_DATA_EXT(STM_MODE_ANALOG, GPIO_NOPULL, 0, 17, 0)}, // ADC_IN17
     {NC,   NC,    0}
 };
 
diff --git a/targets/TARGET_STM/TARGET_STM32F1/TARGET_NUCLEO_F103RB/PinNames.h b/targets/TARGET_STM/TARGET_STM32F1/TARGET_NUCLEO_F103RB/PinNames.h
index b1a1d2397a..cbfd8f673d 100644
--- a/targets/TARGET_STM/TARGET_STM32F1/TARGET_NUCLEO_F103RB/PinNames.h
+++ b/targets/TARGET_STM/TARGET_STM32F1/TARGET_NUCLEO_F103RB/PinNames.h
@@ -46,9 +46,9 @@ extern "C" {
                                                                        ((CHANNEL  & 0x1F) << 11) |\
                                                                        ((INVERTED & 0x01) << 16)))
 
-#define STM_PIN_MODE(X)   (((X) >> 0) & 0x0F)
-#define STM_PIN_PUPD(X)   (((X) >> 4) & 0x07)
-#define STM_PIN_AFNUM(X)  (((X) >> 7) & 0x0F)
+#define STM_PIN_MODE(X)     (((X) >>  0) & 0x0F)
+#define STM_PIN_PUPD(X)     (((X) >>  4) & 0x07)
+#define STM_PIN_AFNUM(X)    (((X) >>  7) & 0x0F)
 #define STM_PIN_CHANNEL(X)  (((X) >> 11) & 0x1F)
 #define STM_PIN_INVERTED(X) (((X) >> 16) & 0x01)
 
@@ -132,6 +132,7 @@ typedef enum {
 
     // ADC internal channels
     ADC_TEMP = 0xF0,
+    ADC_VREF = 0xF1,
 
     // Arduino connector namings
     A0          = PA_0,
diff --git a/targets/TARGET_STM/TARGET_STM32F1/analogin_api.c b/targets/TARGET_STM/TARGET_STM32F1/analogin_api.c
index 5230697cbd..44e830b92b 100644
--- a/targets/TARGET_STM/TARGET_STM32F1/analogin_api.c
+++ b/targets/TARGET_STM/TARGET_STM32F1/analogin_api.c
@@ -52,8 +52,8 @@ void analogin_init(analogin_t *obj, PinName pin)
     MBED_ASSERT(function != (uint32_t)NC);
     obj->channel = STM_PIN_CHANNEL(function);
 
-    // Configure GPIO excepted for internal channels (Temperature)
-    if (obj->channel != 16) {
+    // Configure GPIO excepted for internal channels (Temperature, Vref)
+    if ((obj->channel != 16) && (obj->channel != 17)) {
         pinmap_pinout(pin, PinMap_ADC);
     }
 
@@ -152,6 +152,9 @@ static inline uint16_t adc_read(analogin_t *obj)
         case 16:
             sConfig.Channel = ADC_CHANNEL_16;
             break;
+        case 17:
+            sConfig.Channel = ADC_CHANNEL_17;
+            break;
         default:
             return 0;
     }