The Low Power Mode 4.5 (LPM4.5) is used to achieve lowest power consumption in the MSP430F5xx devices. When the device enters LPM4.5, the internal regulator of the Power Management Module (PMM) is disabled, thus switching off the supply voltage that is used to power the device core. The device core includes the JTAG and debug (EEM) logic of the device. To debug code while the device enters or exits the LPM4.5, special considerations and debug techniques are required. This application report discusses the LPM4.5 debugging procedures to be followed for the debugger to synchronized with the device when entering and exiting LPM4.5.