64-Bit Micro Targets Entry-Level Smartphones
ARM’s new 64-bit Cortex-A35 looks to replace the 32-bit Cortex-A5 and Cortex-A7 microcontrollers for applications such as entry-level smartphones and in the Internet of Things (IoT) applications where low power, low cost, and 64-bit performance are key features (Fig. 1). The Cortex-A35 is based on the ARMv8-A architecture.
The Cortex-A35 architecture should be the most energy-efficient 64-bit mobile chip yet. It uses 32 percent less power than the mid-range Cortex-A53 and the core is 25 percent smaller. It also runs 6% to 40% faster than the Cortex-A7. Chips based on the Cortex-A35 should show up in later 2016.
The Cortex-A35 can be the little part of a big.LITTLE architecture. It could be combined with Cortex-A5x or Cortex-A7x cores.
The Cortex-A35, like the Cortex-A7 and the Cortex-A53, uses an in-order pipeline. ARM has redesigned the front end instruction decode so it has better branch prediction support. It also has a smaller and more power efficient instruction queue with a more balanced instruction fetch bandwidth. The 512-entry translation lookaside buffer (TLB) is twice the size found in the Cortex-A7.