NVidia's Tegra 4 has a four Cortex-A15 cores plus a fifth low power core. The GeForce GPU adds 72 GPU cores.
Nvidia’s Tegra 4 system-on-chip (SoC) can be paired with the company’s Icera i500 processor to deliver a high-performance 4G LTE voice and data platform (Fig. 1). The Tegra 4’s five Cortex-A15 cores offer more than twice the performance of the Tegra 3, which is based on the Cortex-A9. Also, its 72 GPU cores boost multimedia processing by a factor of six compared to the Tegra 3. The Icera i500 processor ships with LTE UE Category 3 with 100-Mbit/s downlink support.
Figure 1. Nvidia’s Tegra 4 SoC (left) and Icera i500 4G LTE processor (right) target mobile and gaming applications. The Tegra 4 has five Cortex-A15 cores plus 72 GPU cores.
Four of the Cortex-A15 cores provide the high-performance support while the fifth core is designed for low-power operation. Like the Tegra 3, the Tegra 4 uses one core or four cores at a time. The video support can handle 4K ultra-high-def video. The 72-core GeForce GPU can do more than just boost gaming and display performance. It also could reduce the time to deliver high dynamic range (HDR) image support, which tends to be computationally heavy.
Nvidia implemented the chip using 28-nm HPL high-K metal gate technology, which provides low-power operation while allowing the cores to run at 1.9 GHz. The 80-mm2 chip is only slightly larger than the Tegra 3. It supports LP-DDR3 via a dual channel, 32-bit memory interface.
The Tegra 4 also powers Nvidia’s Shield open gaming platform (Fig. 2). Using 802.11n technology, the Android system links to wireless displays. Its own 5-in. multitouch display boasts 1280- by 720-pixel resolution with 294-dpi density. It includes an HDMI port and microSD slot. And, it runs for five to 10 hours when playing games and 20 hours when playing HD video.
Figure 2. The Shield gaming platform is based on the Tegra 4. It supports 1080p gaming.
The Tegra 3 had a lot of company in the Cortex-A9 space, like Texas Instruments’ quad-core OMAP 4470 and Freescale’s i.MX6 series, but it still gained a good bit of traction in the mobile device space. The Tegra 4 is the natural upgrade. It’s faster and uses less power than its predecessor, so its success is ensured. The Shield’s success may take a little longer. It’s a neat idea and well executed, though, and several major game publishers already support it.
