I am attaching several slides describing MPC5643L architecture. It offers two modes LSM and DPM. Page 2 shows their comparison.
Page 3 shows spheres of replication (i.e. Lake) executing the same tasks in LSM mode.
On the place, where replicated and non-replicated part touches, lies redundancy checker. It checks whether bus content is equal - if no, fault is reported to FCCU module and FCCU takes appropriate action (MCU can go to safe mode, interrupt or reset can occur according to particular fault severity, report this condition to supervisory system on FCCU pins and so on).
Typical application is in the systems where possible faults are not easily tolerated and malfunction could lead in injuries or damages of people health. It is called safety systems. Examples:
Airbag Systems, Electronic Stability Control, Electric Power Steering, Braking, …
In non-automotive applications Robotics, Industrial Automation, Medical Appliances and so on…
Another point why to use LSM mode for developing your safety application is existence of safety manual what's such guide telling how to develop functional safety system:
http://www.nxp.com/docs/en/user-guide/MPC5643LSM.pdf
You may see following white paper discussing DPM/LSM pros and cons:
http://www.nxp.com/docs/en/white-paper/MPC564XLWP.pdf
To simplify it - LSM is mode is suitable for safety application, DPM for applications where more performance is needed (and integrated special safety HW is disabled).
