The Raspberry Pi project has announced the sale of a new generation of the Raspberry Pi Zero W board, combining compact size with Bluetooth and Wi-Fi support. The new Raspberry Pi Zero 2 W model is made in the same mini form factor (65 x 30 x 5 mm), making it roughly half the size of a regular Raspberry Pi. Sales have only begun in the UK, EU, USA, Canada, and Hong Kong, with shipments to other countries opening as the wireless module certification is completed. The price of the Raspberry Pi Zero 2 W is set at $15 (for comparison, the Raspberry Pi Zero W costs $10, while the Raspberry Pi Zero is $5, and production of the cheaper boards will continue).
A key distinction of the new Raspberry Pi Zero model is the switch to the Broadcom BCM2710A1 SoC, similar to that used in Raspberry Pi 3 boards (the previous Zero generation used the Broadcom BCM2835 SoC, as in the first Raspberry Pi). Unlike the Raspberry Pi 3, the processor frequency has been reduced from 1.4GHz to 1GHz to decrease power consumption. According to the sysbench multi-threaded test, the SoC upgrade has allowed a fivefold increase in board performance (the new SoC features a quad-core 64-bit Arm Cortex-A53 CPU instead of the single-core 32-bit ARM11 ARM1176JZF-S).
As in the previous version, the Raspberry Pi Zero 2 W offers 512MB of RAM, a Mini-HDMI port, two Micro-USB ports (USB 2.0 with OTG and a power input), a microSD slot, and a 40-pin GPIO header (not soldered), along with outputs for composite video and camera (CSI-2). The board is equipped with a wireless chip that supports Wi-Fi 802.11 b/g/n (2.4GHz), Bluetooth 4.2, and Bluetooth Low Energy (BLE). To meet FCC certification and protect against external interference, the wireless chip on the new board is covered with a metal shield.
The integrated GPU in the SoC supports OpenGL ES 1.1 and 2.0, providing resources for accelerating video decoding in H.264 and MPEG-4 formats at 1080p30 quality, as well as encoding in H.264 format, which broadens the board's applicability across various multimedia devices and smart home systems. Unfortunately, the RAM size is limited to 512 MB and cannot be expanded due to physical constraints of the board size. Supplying 1GB of RAM would require a complex multi-layer construction that the developers are not yet ready to implement.
The main challenge in designing the Raspberry Pi Zero 2 W board was addressing the placement of LPDDR2 SDRAM memory. In the first generation of the board, the memory was placed in an additional layer above the SoC chip using PoP (package-on-package) technology, but this approach could not be implemented in the new Broadcom chips due to the increased size of the SoC. To solve this issue, a special variant of the chip was developed in collaboration with Broadcom, which integrated the memory into the SoC.
Another issue was the increased heat output due to the use of a more powerful processor. This problem was resolved by adding thick copper layers to the board for heat dissipation away from the processor. As a result, the weight of the board noticeably increased, but the solution proved effective, being sufficient to prevent overheating during an unlimited-duration stress test of linear algebra using LINPACK at an ambient temperature of 20 degrees.
Among competing devices, the closest competitor to the Raspberry Pi Zero 2 W is the Chinese board Orange Pi Zero Plus2, which measures 46×48mm and retails for $35 with 512MB of RAM and an Allwinner H3 chip. The Orange Pi Zero Plus2 features 8 GB of EMMC Flash, a full HDMI port, a TF Card slot, USB OTG, as well as contacts for connecting a microphone, infrared receiver (IR), and two additional USB ports. It is powered by a quad-core Allwinner H5 processor (Cortex-A53) with a Mali450 GPU or an Allwinner H3 (Cortex-A7) with a Mali400MP2 GPU. Instead of a 40-pin GPIO, it comes with a reduced 26-pin connector compatible with Raspberry Pi B+. A less powerful Orange Pi Zero 2 is also available, equipped with 1 GB of RAM and an Ethernet port in addition to Wi-Fi.
Source: opennet.ru
