SP7021: A LINUX CHIP FOR IOT AND INDUSTRIAL CONTROL APPLICATIONS
“The power of Linux. The simplicity of a micro-controller."
SP7021 is a revolutionary SoC that has the power of a Linux-grade chip and the integration simplicity of a micro-controller.
Conceived by Sunplus Technology in collaboration with Tibbo Technology , SP7021 takes all the sophisticated elements typically found in modern industrial-grade embedded Linux chips, adds a plethora of features targeting IoT and industrial control applications, and delivers the resulting design in a simple microcontroller-like package that needs few external components, simplifies the schematic diagram, and reduces the PCB complexity.
1.1. Story of SP7021
Although there are many embedded Linux CPUs on the market, few were designed to address the needs of the IoT and industrial control markets directly. In fact, most CPUs found on popular boards such as Raspberry Pi were initially meant for something else (for example, a Single Board Computer (SBC) for education) and were merely repurposed for the needs of the IoT and industrial control communities.
Such CPUs usually have adequate processing power but deficiencyin the IO features. This is not surprising, as set-top boxes have very different IO needs than IoT or industrial control devices. These CPUs are also rather complex, need multiple additional components to work, and they are available only in difficult-to-handle BGA packaging, and require six- or eight-layer boards. All of these pose severe obstacles to low- and medium-volume device vendors.
Take the BGA packaging as an example. Everything about BGA is an order of magnitude more complex compared to other packaging choices, such as LQFP. BGA represents the cut-off line, at which it becomes impossible to handle the chips manually. Everything, from soldering to de-soldering, to verifying the assembly quality requires specialized and expensive equipments. Smartphone manufacturers accept BGA challenges as the inevitable side effect of the desired board miniaturization that BGA technology enables, but vendors of IoT or industrial control devices view this differently. IoT and industrial control products rarely require small sizes, and having to deal with ever smaller IC packages only brings complications without any apparent benefits.
As another example, consider the logic levels of GPIO lines. As processor designs took advantage of more and more advanced fabrication processes, chip supply voltages decreased too. With that, standard semiconductor IO libraries have dropped the support for 5V first, and then even for 3.3V logic levels. This did not bother the designers of set-top boxes and other "closed" products but was bad news for the architects of control hardware.
To summarize, there was an apparent gap between existing processor offerings and the requirements of the IoT and industrial control applications. Recognizing the unmet needs of IoT and industrial control vendors, in late 2017 Sunplus and Tibbo Technology have set out to develop a Linux-grade chip that could address these markets directly. The idea was to create a powerful SoC with IO features and packaging targeting specifically the IoT and the industrial control applications, as well as the needs of low- and medium-volume hardware manufacturers. Thus, the Plus1 concept was born.
1.2 Here are the key characteristics of the SP7021 SoC
Powerful ARM Cortex-A7 Quad core
Single 3.3V power; integrated power controller and regulators for all additional voltages
DRAM chip onboard
Available simple-to-use LQFP packaging
Flexible mapping of peripherals to chip pins
5V-tolerant 3.3V-level IO lines
Dual Ethernet MAC controllers with the built-in Ethernet switch fabric
Five enhanced UARTs as well as SPI/I2C, timers, PWM, and other peripherals
Abundant interface which include USB, HDMITX, MIPICSI, I2S and SPDIF
A special interface to connect with FPGA
Industrial operating temperature range (-40 ~ +85 C)
Low EMI for simplified Class B CE/FCC certification
Many more peripherals and features
Robust ready-to-run modern Linux distribution available