diff --git a/boards/arduino-mega2560/doc.txt b/boards/arduino-mega2560/doc.txt
index fcdf4c4a88..b598da89c9 100644
--- a/boards/arduino-mega2560/doc.txt
+++ b/boards/arduino-mega2560/doc.txt
@@ -16,8 +16,7 @@ again.
 
 ## Hardware
 
-![Arduino Mega2560](http://userpage.zedat.fu-
-berlin.de/~hvbruinehsen/IMG_20140923_100817.jpg)
+![Arduino Mega2560](https://store-cdn.arduino.cc/uni/catalog/product/cache/1/image/500x375/f8876a31b63532bbba4e781c30024a0a/a/0/a000067_front_1_.jpg)
 
 ### MCU
 | MCU        | ATmega2560        |
diff --git a/boards/frdm-k64f/doc.txt b/boards/frdm-k64f/doc.txt
index 90f39db979..16305a0b85 100644
--- a/boards/frdm-k64f/doc.txt
+++ b/boards/frdm-k64f/doc.txt
@@ -8,8 +8,7 @@ The board has a K64F Kinetis MCU and is supported by `cpu/kinetis_common`.
 
 ## Hardware
 
-![frdm-k64f](http://cache.freescale.com/files/graphic/block_diagram/31958-FRD
-M-K64F_BDTN.jpg)
+![frdm-k64f](https://www.nxp.com/assets/images/en/dev-board-image/BOARD-FRDM-K64F-PRODUCT-SHOT.png)
 
 | MCU        | MK64FN1M0VLL12        |
 |:------------- |:--------------------- |
diff --git a/boards/nrf52840-mdk/doc.txt b/boards/nrf52840-mdk/doc.txt
index 9e9024ebad..043399369d 100644
--- a/boards/nrf52840-mdk/doc.txt
+++ b/boards/nrf52840-mdk/doc.txt
@@ -11,8 +11,7 @@ This board provides 802.15.4 and BLE connectivity.
 
 ### Pinout
 
-<img src="https://github.com/makerdiary/nrf52840-mdk/blob/master/docs/images/nrf52840-mdk-pinout.jpg"
-     alt="pinout" style="height:800px;"/>
+![nRF52840-MDK](https://github.com/makerdiary/nrf52840-mdk/blob/master/docs/images/nrf52840-mdk-pinout.jpg?raw=true)
 
 ### Flash the board
 
diff --git a/boards/saml11-xpro/doc.txt b/boards/saml11-xpro/doc.txt
index dd0f030ae9..2c64efc106 100644
--- a/boards/saml11-xpro/doc.txt
+++ b/boards/saml11-xpro/doc.txt
@@ -12,7 +12,7 @@ memory. In addition, this SoC features the ARM TrustZone technology.
 
 ## Hardware
 
-![saml11-xpro image](https://www.microchip.com/_ImagedCopy/SAML11%20Xpro%20Front%20Title.jpg)
+![saml11-xpro image](https://www.microchip.com/_ImagedCopy/Converted-146683-1559149241-C16616-180424-MCU32-PHOTO-DM320205-Front-Transparent.png)
 
 
 ### MCU
diff --git a/boards/sodaq-autonomo/doc.txt b/boards/sodaq-autonomo/doc.txt
index 681e6a8b38..0872e1f9cc 100644
--- a/boards/sodaq-autonomo/doc.txt
+++ b/boards/sodaq-autonomo/doc.txt
@@ -13,7 +13,7 @@ The Autonomo is available from the SODAQ [shop](http://shop.sodaq.com/).
 
 ## Hardware
 
-![sodaq-autonomo image](http://static.webshopapp.com/shops/104792/files/050759716/sodaq-sodaq-autonomo.jpg)
+![sodaq-autonomo image](https://support.sodaq.com/Boards/Autonomo/sodaq_autonomo.png)
 
 
 ### MCU
diff --git a/boards/sodaq-sara-aff/doc.txt b/boards/sodaq-sara-aff/doc.txt
index 4b0de3d1b9..fcad988c6f 100644
--- a/boards/sodaq-sara-aff/doc.txt
+++ b/boards/sodaq-sara-aff/doc.txt
@@ -8,8 +8,7 @@
  * General information about this board can be found on the
  * [SODAQ support](http://support.sodaq.com/sodaq-one/sodaq-sara-r410m/)
  * website.
- * ![SODAQ SARA AFF]( https://support.sodaq.com/wp-content/uploads/2018/07/sodaq-sara-pins-768x862.png
-)
+ * ![SODAQ SARA AFF](https://support.sodaq.com/Boards/Sara_AFF/sodaq_sara_aff.png)
  *
  * ### Flash the board
  *
diff --git a/boards/stm32f3discovery/doc.txt b/boards/stm32f3discovery/doc.txt
index f3d04929b6..34e50a7905 100644
--- a/boards/stm32f3discovery/doc.txt
+++ b/boards/stm32f3discovery/doc.txt
@@ -20,7 +20,7 @@ for a quick getting started guide.
 
 ## Hardware
 
-![STM32F3discovery image](http://www.st.com/st-web-ui/static/active/en/fragment/product_related/rpn_information/board_photo/stm32f3discovery.jpg)
+![STM32F3discovery image](https://www.st.com/bin/ecommerce/api/image.PF254044.en.feature-description-include-personalized-no-cpn-large.jpg)
 
 
 ### MCU
diff --git a/cpu/esp8266/doc.txt b/cpu/esp8266/doc.txt
index afd263ce52..3f39b4e5a9 100644
--- a/cpu/esp8266/doc.txt
+++ b/cpu/esp8266/doc.txt
@@ -1164,7 +1164,7 @@ for example:
 ```
 #include "esp/common_macros.h"
 ...
-voir IRAM my_func(void)
+void IRAM my_func(void)
 {
     ...
 }