Motorola Inc. announced a new applications processor last month that is designed to improve the performance of multimedia applications and the security of mobile transactions in cell phones and PDAs.
Basic voice-only cell phones have traditionally used two processors, a digital signal processor to manage the communication process, and another to operate the phone’s keypad, contacts list and calendar operations. But with the rise of new smart phones that incorporate digital cameras and connect to broadband networks, a third processor is often needed to ensure that audio and video playback runs smoothly.
Motorola, based in Schaumburg, Ill., chose to add several hardware accelerators to the new i.MX21 chip in order to offload computationally intensive tasks required by software for security applications and streaming video, said Kathleen Wiggenhorn, i.MX product marketing manager.
By executing those tasks in a hardware accelerator rather than by sending software instructions through the main processor, Motorola reduced the power consumption and improved the overall performance of the chip, Wiggenhorn said.
The hardware accelerator used for the security controller allows several pieces of sensitive information, such as credit card numbers or digital rights management code, to be stored in a secure portion of the chip away from the memory, Wiggenhorn said.
Motorola placed a USB controller on the chip so users could connect other peripheral devices, such as printers or mice, to their PDA or cell phone without having to go through a PC. The chip can switch from a USB device mode to a USB host mode, allowing it to either serve as the peripheral to a PC or the host of a device such as a printer, Wiggenhorn said.
The chip also supports smart liquid crystal displays (LCDs) that refresh themselves only when they detect that an image has changed on the screen. Normal LCD displays must constantly refresh in order to detect changes in onscreen images, which consumes a great deal of power, Wiggenhorn said. The i.MX21 is based on the ARM926EJ-S core developed by ARM Ltd. It can be used by device designers as the applications processor in a smart phone, or it can power a PDA as a stand-alone chip.
