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The Apple A5 is a 32-bit system-on-a-chip designed by Apple Inc. and manufactured by Samsung〔 "The powerful A5 processor, which uses technology licensed from Britain's ARM Holdings, is designed by Apple in California, by a team formerly part of PA Semi – an American chip design company that Apple bought in April 2008."〕 and is the successor to the Apple A4. The A5 commercially debuted with the release of Apple's iPad 2 tablet, and also powers the iPhone 4S, iPod Touch fifth generation, Apple TV third generation, and the iPad mini. This is consistent with how Apple debuted the A4 chip: first in the original iPad, followed by the iPhone 4, and then the iPod Touch (fourth generation). Apple claims that compared to its predecessor, the A4, the A5 CPU "can do twice the work" and the GPU has "up to nine times the graphics performance". Currently, as of July 19, 2015, the Apple TV is the only hardware that uses the A5 chip. == Design == The A5 consists of a dual-core ARM Cortex-A9 MPCore CPU with NEON SIMD accelerator and a dual core PowerVR SGX543MP2 GPU. Apple lists the A5 to be clocked at 1 GHz on the iPad 2's technical specifications page, though it can dynamically adjust its frequency to save battery life.〔(【引用サイトリンク】title=Inside Apple's iPad 2 A5: fast LPDDR2 RAM, costs 66% more than Tegra 2 )〕〔 The unit used in the iPhone 4S is clocked at approximately 800 MHz.〔(iPhone 4S Preliminary Benchmarks: ~800MHz A5, Slightly Slower GPU than iPad 2, Still Very Fast )〕 Apple has also included an image signal processor unit (ISP) that will do advanced image post-processing such as face detection, white balance and automatic image stabilization〔(【引用サイトリンク】title=Apple Announces iPhone 4S: A5, 8 MP Camera, 1080p Video Recording )〕 and an "earSmart" unit from Audience for noise canceling.〔(【引用サイトリンク】title=Why Apple's A5 is so big—and iPhone 4 won't get Siri )〕 When the A5 was first released, it was estimated at that time to cost 75% more than the previous generation, with the difference expected to diminish as production increased. , the A5 is manufactured at Samsung's Austin, Texas factory. Samsung invested $3.6 billion in the Austin facility to produce chips such as processors, and nearly all of that wing's output is dedicated to Apple components. Samsung has invested a further $4.2 billion at the Austin facility in order to transition to a 28 nm fabrication process by the second half of 2013.〔 The A5 part model numbers are: S5L8940 (45 nm version), S5L8942 (32 nm version) and S5L8947 (32 nm, single core version). A version of the A5 with a wider memory subsystem and four graphic cores is called Apple A5X and is found in the third generation iPad. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Apple A5」の詳細全文を読む スポンサード リンク
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