Apple's new MacBook appears to contain a PCIe SSD that supports NVM express. Apple has also used a custom controller to control the Toshiba MLC NAND memory on the small sized SSD.
The controller in the new Macbook supports NVMHCI (Non Volatile Memory Host Controller Interface Express). This successor of the AHCI interface is optimized for SSDs and doesn't only increase bandwidth but also lowers the latency and performs better when CPUs with multithreading are used.
The NVM Express controller, which was discovered by iFixit when the website tore down a MacBook, is part of a package that also includes 512MB LPDDR3 cache memory from SK Hynix. Although the controller appears to be specifically designed for Apple, it's unclear which company has designed the controller.
