diff --git a/libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32F4/TARGET_NUCLEO_F446RE/PeripheralNames.h b/libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32F4/TARGET_NUCLEO_F446RE/PeripheralNames.h
index cfbe6e43a6..6ad47076c4 100644
--- a/libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32F4/TARGET_NUCLEO_F446RE/PeripheralNames.h
+++ b/libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32F4/TARGET_NUCLEO_F446RE/PeripheralNames.h
@@ -80,6 +80,7 @@ typedef enum {
     PWM_9  = (int)TIM9_BASE,
     PWM_10 = (int)TIM10_BASE,
     PWM_11 = (int)TIM11_BASE,
+    PWM_12 = (int)TIM12_BASE,
     PWM_13 = (int)TIM13_BASE,
     PWM_14 = (int)TIM14_BASE
 } PWMName;
diff --git a/libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32F4/TARGET_NUCLEO_F446RE/PeripheralPins.c b/libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32F4/TARGET_NUCLEO_F446RE/PeripheralPins.c
index 2c7fdbae40..d933d8d8f3 100644
--- a/libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32F4/TARGET_NUCLEO_F446RE/PeripheralPins.c
+++ b/libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32F4/TARGET_NUCLEO_F446RE/PeripheralPins.c
@@ -106,7 +106,7 @@ const PinMap PinMap_PWM[] = {
 //  {PA_5,  PWM_8, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF3_TIM8, 1, 1)}, // TIM8_CH1N
     {PA_6,  PWM_3, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM3, 1, 0)}, // TIM3_CH1
 //  {PA_6,  PWM_13,STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF9_TIM13,1, 0)}, // TIM13_CH1
-    {PA_7,  PWM_1, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF1_TIM1, 1, 1)}, // TIM1_CH1N - ARDUINO
+    {PA_7,  PWM_1, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF1_TIM1, 1, 1)}, // TIM1_CH1N - ARDUINO D11
 //  {PA_7,  PWM_3, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM3, 2, 0)}, // TIM3_CH2
 //  {PA_7,  PWM_8, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF3_TIM8, 1, 1)}, // TIM8_CH1N
 //  {PA_7,  PWM_14,STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF9_TIM14,1, 0)}, // TIM14_CH1
@@ -123,10 +123,10 @@ const PinMap PinMap_PWM[] = {
 //  {PB_1,  PWM_3, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM3, 4, 0)},  // TIM3_CH4
 //  {PB_1,  PWM_8, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF3_TIM8, 3, 1)},  // TIM8_CH3N
     {PB_2,  PWM_2, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF1_TIM2, 4, 0)},  // TIM2_CH4
-    {PB_3,  PWM_2, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF1_TIM2, 2, 0)},  // TIM2_CH2 - ARDUINO
-    {PB_4,  PWM_3, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM3, 1, 0)},  // TIM3_CH1 - ARDUINO
+    {PB_3,  PWM_2, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF1_TIM2, 2, 0)},  // TIM2_CH2 - ARDUINO D3
+    {PB_4,  PWM_3, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM3, 1, 0)},  // TIM3_CH1 - ARDUINO D5
     {PB_5,  PWM_3, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM3, 2, 0)},  // TIM3_CH2
-    {PB_6,  PWM_4, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM4, 1, 0)},  // TIM4_CH1 - ARDUINO
+    {PB_6,  PWM_4, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM4, 1, 0)},  // TIM4_CH1 - ARDUINO D10
     {PB_7,  PWM_4, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM4, 2, 0)},  // TIM4_CH2
     {PB_8,  PWM_4, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM4, 3, 0)},  // TIM4_CH3
 //  {PB_8,  PWM_2, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF1_TIM2, 1, 0)},  // TIM2_CH1
@@ -134,7 +134,7 @@ const PinMap PinMap_PWM[] = {
     {PB_9,  PWM_4, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM4, 4, 0)},  // TIM4_CH4
 //  {PB_9,  PWM_2, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF1_TIM2, 2, 0)},  // TIM2_CH2
 //  {PB_9,  PWM_11,STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF3_TIM11,1, 0)},  // TIM11_CH1
-    {PB_10, PWM_2, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF1_TIM2, 3, 0)},  // TIM2_CH3 - ARDUINO
+    {PB_10, PWM_2, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF1_TIM2, 3, 0)},  // TIM2_CH3 - ARDUINO D6
     {PB_13, PWM_1, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF1_TIM1, 1, 1)},  // TIM1_CH1N
     {PB_14, PWM_1, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF1_TIM1, 2, 1)},  // TIM1_CH2N
 //  {PB_14, PWM_8, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF3_TIM8, 2, 1)},  // TIM8_CH2N
@@ -145,7 +145,7 @@ const PinMap PinMap_PWM[] = {
 
     {PC_6,  PWM_3, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM3, 1, 0)},  // TIM3_CH1
 //  {PC_6,  PWM_8, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF3_TIM8, 1, 0)},  // TIM8_CH1
-    {PC_7,  PWM_3, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM3, 2, 0)},  // TIM3_CH2 - ARDUINO
+    {PC_7,  PWM_3, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM3, 2, 0)},  // TIM3_CH2 - ARDUINO D9
 //  {PC_7,  PWM_8, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF3_TIM8, 2, 0)},  // TIM8_CH2
     {PC_8,  PWM_3, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF2_TIM3, 3, 0)},  // TIM3_CH3
 //  {PC_8,  PWM_8, STM_PIN_DATA_EXT(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF3_TIM8, 3, 0)},  // TIM8_CH3