SLAA419C October 2009 – April 2019 MSP430F5418 , MSP430F5418A , MSP430F5419 , MSP430F5419A , MSP430F5435 , MSP430F5435A , MSP430F5436 , MSP430F5436A , MSP430F5437 , MSP430F5437A , MSP430F5438 , MSP430F5438A
Fortunately, the F543xA versions of silicon have very few differences from the F543x versions that affect an application's hardware design. The package and pinout of the A versions is pin-to-pin compatible with the F543x versions.