diff --git a/cores/arduino/wiring_analog.c b/cores/arduino/wiring_analog.c
index 2a8421a..cdf1226 100644
--- a/cores/arduino/wiring_analog.c
+++ b/cores/arduino/wiring_analog.c
@@ -148,7 +148,7 @@ It is recommended to turn off the timer in the following order:
 */
 void analogWriteStop(uint32_t PinNumber)
 {
-  if (pwmIsInited > 0)
+  if ((pwmIsInited > 0) && (digitalPinPwmIsOn(PinNumber)))
   {
     // load the timer address and channel number corresponding to the specified pin
     htimer32.Instance               = pwmPinToTimer(PinNumber);
@@ -164,6 +164,10 @@ void analogWriteStop(uint32_t PinNumber)
       HAL_Timer32_Stop(&htimer32);
       HAL_Timer32_Deinit(&htimer32);
     }
+
+    // config pin as input when timer channel off
+    HAL_GPIO_PinConfig(digitalPinToPort(PinNumber), digitalPinToBitMask(PinNumber), 
+                      HAL_GPIO_MODE_GPIO_INPUT, HAL_GPIO_PULL_NONE, HAL_GPIO_DS_2MA);
   }
 }
 
diff --git a/variants/standart/pins_arduino.h b/variants/standart/pins_arduino.h
index 5f59b36..16dc84b 100644
--- a/variants/standart/pins_arduino.h
+++ b/variants/standart/pins_arduino.h
@@ -76,6 +76,7 @@ uint32_t analogInputToChannelNumber(uint32_t PinNumber);
 
 // PWM
 bool digitalPinHasPWM(uint8_t p);
+bool digitalPinPwmIsOn(uint8_t digitalPin); // use only if digitalPinHasPWM() == true
 // determines which timer the pin belongs to
 TIMER32_TypeDef* pwmPinToTimer(uint32_t digPinNumber);
 // determines which timer channel the pin belongs to
diff --git a/variants/standart/variant.c b/variants/standart/variant.c
index 1cec497..62b59fb 100644
--- a/variants/standart/variant.c
+++ b/variants/standart/variant.c
@@ -107,6 +107,10 @@ volatile uint32_t* portInputRegister(GPIO_TypeDef* GPIO_x)
   return &GPIO_x->STATE;
 }
 
+// return config of pin with pinShift(0...16) in portReg (config, pupd, ds for ports 0...2)
+#define PIN_PAD_CONFIG(portReg, pinShift)   ((PAD_CONFIG->portReg  >> (pinShift<<1)) & 0b11)
+
+
 // ---------------------- ADC ---------------------- //
 // determines the ADC channel number by the board pin number
 uint32_t analogInputToChannelNumber(uint32_t PinNumber)
@@ -142,6 +146,38 @@ uint32_t analogInputToChannelNumber(uint32_t PinNumber)
 }
 
 // ---------------------- PWM ---------------------- //
+// use only if digitalPinHasPWM() == true
+#define PWM_PIN_TO_PORT_NUMBER(pin)           (((pin==10)||(pin==11)) ? 1:0)
+// use only if digitalPinHasPWM() == true
+static inline uint8_t pwmPinToGpioPinShift(uint8_t digitalPin)
+{
+  if (digitalPin == 3)
+    return 0;
+  else if ((digitalPin == 5) || (digitalPin == 11))
+    return 1;
+  else if (digitalPin == 6)
+    return 2;
+  else // pins 9 10
+    return 3; 
+}
+// use only if digitalPinHasPWM() == true
+// return true if digitalPin configured as pwm
+bool digitalPinPwmIsOn(uint8_t digitalPin)
+{
+  uint8_t config = 0;
+  uint8_t pinShift = pwmPinToGpioPinShift(digitalPin);
+
+  if (PWM_PIN_TO_PORT_NUMBER(digitalPin) == 0)
+    config = PIN_PAD_CONFIG(PORT_0_CFG, pinShift);
+  else 
+    config = PIN_PAD_CONFIG(PORT_1_CFG, pinShift);
+
+  if (config == 2)
+    return true;
+  else
+    return false;
+}
+
 bool digitalPinHasPWM(uint8_t p)   
 {
   bool ret = false;
@@ -232,7 +268,6 @@ int8_t digitalPinToInterrupt(uint32_t digPinNumber)
 // pins shift in registers
 #define PIN_3_SHIFT  3
 #define PIN_4_SHIFT  4
-#define PORT1_GET_PAD_CONFIG(pinShift)  ((PAD_CONFIG->PORT_1_CFG  >> (pinShift<<1)) & 0b11)
 #define PORT1_GET_PAD_PUPD(pinShift)    ((PAD_CONFIG->PORT_1_PUPD >> (pinShift<<1)) & 0b11)  
 #define PORT1_GET_GPIO_STATE(pinShift)  ((GPIO_1->OUTPUT_ >> pinShift) & 0b1)  
 
@@ -242,7 +277,7 @@ void spi_onBegin(void)
   // because spi needs pin 1.3 for correct work
 
   // replace config from 1.3 to 1.4 
-  uint8_t config = PORT1_GET_PAD_CONFIG(PIN_3_SHIFT);
+  uint8_t config = PIN_PAD_CONFIG(PORT_1_CFG, PIN_3_SHIFT);
   if (config == 0)    // common gpio
   {
     // get info from pin gpio1.3 and set config to gpio1.4