Key difference: Both DSP and ARM Processors are types of microprocessors. A microprocessor is a silicon chip that contains the central processing unit (CPU) of the device. The ARM Processors are based on the RISC design of computer processors. The RISC microprocessors are usually for generic usage. The DSP processor is another type of microprocessor. DSP stands for digital signal processing. It is basically any signal processing that is done on a digital signal or information signal. A DSP processor is a specialized microprocessor that has an architecture optimized for the operational needs of digital signal processing.

Both DSP and ARM Processors are types of microprocessors. A microprocessor is a silicon chip that contains the central processing unit (CPU) of the device. It incorporates the functions of a computer's CPU on a single or few integrated circuits. The purpose of a microprocessor is to accept digital data as input, process it as per the instructions, and then provide the output. This is known as sequential digital logic. The microprocessor has internal memory and operates basically on the binary system.

The ARM Processors are based on the RISC design of computer processors. The RISC microprocessors are usually for generic usage. There are many other microprocessor families, other than ARM that are based on RISC, such as Intel i860 and i960, MIPS and more.

The ARM Processors are designed and licensed by ARM Holdings. As of 2013, the ARM Processors were the most widely used 32-bit instruction set architecture in terms of quantity produced globally. The ARM-based processors and systems on a chip include the Qualcomm Snapdragon, nVidia Tegra, Marvell Xscale and Texas Instruments OMAP, as well as ARM's Cortex series and Apple System on Chips, which are used in iPhones.

As compared to other processors used in traditional computers, the ARM processors require significantly fewer transistors. This results in reduced costs, less heat, and less power usage than other processors. Hence, ARM processors are well known and desired for light, portable, battery-powered devices such as smart phones and tablet computers.

Furthermore, the reduced complexity and simpler design of ARM processors allows companies to build a low-energy system on a chip for an embedded system. The embedded system would incorporate memory, interfaces, radios, etc. The simpler design of ARM processors also allows more efficient multi-core CPUs and higher core counts at lower cost levels. Moreover, it allows higher levels of processing power and improved energy efficiency for servers and laptops and notepad computers.

The DSP processor is another type of microprocessor. DSP stands for digital signal processing. It is basically any signal processing that is done on a digital signal or information signal. A DSP processor is a specialized microprocessor that has an architecture optimized for the operational needs of digital signal processing.

DSP aims to modify or improve the signal. It is characterized by the representation of discrete units, such as discrete time, discrete frequency, or discrete domain signals. DSP includes subfields like communication signals processing, radar signal processing, sensor array processing, digital image processing, etc.

The main goal of a DSP processor is to measure, filter and/or compress digital or analog signals. It does this by converting the signal from a real-world analog signal to a digital form. In order to convert the signal it uses a digital-to-analog converter (DAC). However, the required output signal is often another real-world analog signal. This is turn also requires a digital-to-analog converter.

Digital signal processing algorithms can run on various platforms, such as general purpose microprocessors and standard computers; specialized processors called digital signal processors (DSPs); purpose-built hardware such as application-specific integrated circuit (ASICs) and field-programmable gate arrays (FPGAs); Digital Signal Controllers; and stream processing for traditional DSP or graphics processing applications, such as image, video.

As compared to other microprocessors, a DSP processor has features designed to support high-performance, repetitive, numerically intensive tasks. DSP processors are designed specifically to perform large numbers of complex arithmetic calculations and as quickly as possible. They are often used in applications such as image processing, speech recognition and telecommunications. As compared to general microprocessors, DSP processors are more efficient at performing basic arithmetic operations, especially multiplication.

Most general-purpose microprocessors and operating systems can execute DSP algorithms successfully. However, they are not suitable for use in portable devices such as mobile phones. Hence, specialized digital signal processors are used. Digital Signal Processors have approximately the same level of integration and the same clock frequencies as general purpose microprocessors, but they tend to have better performance, lower latency, and no requirements for specialized cooling or large batteries. This allows them to be a lower-cost alternative to general-purpose microprocessors.

DSPs also tend to be two to three times as fast as general-purpose microprocessors. This is because of architectural differences. DSPs tend to have a different arithmetic Unit architecture; specialized units, such as multipliers, etc.; regular instruction cycle, a RISC-like architecture; parallel processing; a Harvard Bus architecture; an Internal memory organization; multiprocessing organization; local links; and memory banks interconnection.

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