The two figures above outline both the original and modified architecture for a smartphone using the Marvell PXA310 application processor, a Hi-Speed USB 2.0 On-The-Go (OTG) port and a high speed SD controller port.
A carkit is required by most smartphones to allow hand-free operations for customers while driving. It connects the phone directly to the installed car stereo system with a speaker and a microphone. USB OTG is the simplest and most cost-effective way to add the carkit function to a phone. It utilizes the existing USB connection by multiplexing the digital data and analog audio. However the lack of OTG support on many application processors forces designers to look for an external solution.
Another trend in the smartphone market is the ever increasing need for embedded storage. Compared with other options such as micro hard drives and raw NAND flash, Managed NAND provides the most appealing solution for smartphones with high capacity, high reliability and ease of use/management. The downside is that most application processors cannot directly boot from Managed NAND. And therefore they would require an additional NOR flash to boot, which results in higher BOM cost and more board space.
QuickLogic’s CSSP approach enabled this smartphone manufacturer to utilize the USB OTG based carkit interface and differentiate their product from their competitors. Furthermore, QuickLogic’s lowest power customizable building blocks allowed QuickLogic to augment the standard SD/MMC memory controller with booting capability.
As a result of using the QuickLogic CSSP, this smartphone manufacturer met the market requirement for an advanced USB OTG-based carkit. By eliminating the boot NOR flash and having a single flash storage device for boot, programs and data, they were able to lower their system BOM cost and reduce the PCB board space.