The maximum clock frequency for the MSP430F122IDW is 8 MHz, but it can be overclocked up to 16 MHz with reduced voltage and temperature range.
To use an external crystal oscillator, connect the crystal to the XIN and XOUT pins, and configure the UCSCTL6 register to select the external clock source. Also, ensure that the MCLK frequency is set to the desired frequency using the UCSCTL1 register.
The minimum voltage required for the MSP430F122IDW to operate is 1.8V, but it is recommended to operate at 2.2V or higher for optimal performance and to ensure that all peripherals function correctly.
To reduce power consumption on the MSP430F122IDW, use the low-power modes (LPM3, LPM4, etc.) provided by the device, reduce the clock frequency, turn off unused peripherals, and use the built-in brown-out reset (BOR) feature to detect and respond to voltage drops.
No, the MSP430F122IDW is not 5V tolerant and should not be used with a 5V power supply. The maximum recommended voltage is 3.6V, and exceeding this voltage can damage the device.