Some AEMs have a regulated output to power an application circuit. Depending on the AEMs, different converter architectures are available. Some are designed with an LDO, with a BUCK, or with a BUCK_BOOST architecture.
Sometimes, the application circuit can also be supplied directly from the storage element or thanks to an external DCDC connected on the storage element and driven by the status of the AEM. In this case, a regulated output is not mandatory.