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What is the Difference Between CMOS and RTC?



In a world of evolving technology, many terms and miniature foundations connect to form a device. Computer tech has many boards and circuits, which contribute to building the systematic model of the computer. RTC and CMOS are two motherboards in the computing system. Abbreviated as Real-Time Clock and Complementary-symmetry Metal Oxide Conductor, respectively, both motherboard chips are different to each other by function and installation. You can observe key differences between the two, yet they work together.

The Functions of RTC and CMOS

The CMOS is a chip on the motherboard that saves and stores information and instructions about the computer components and systematic settings. It works as a volatile RAM chip that stores values for the RTC; in other words, they work side by side. On the other hand, the RTC board is short for Real-Time Clock, which is an integrated circuit found in almost all electronic devices to keep the accurate time of the day. RTC works as a battery-powered automatic clock fitted in a microchip of the motherboard.

If you are familiar with BIOS (Basic Input Output Operating System) from tech terms, then you can decipher how BIOS reads the RTC chip from ROM (computer's read-only memory).

The Devices and Boards were RTC and CMOS Work



CMOS tech is used for making many types of microchips, microprocessors, memory chips and microcontrollers, used in digital logic circuits, to be exact. CMOS technology is an essential chip fitted in analogue circuits like CMOS sensors and convertors for images and data, respectively. CMOS is also put in high-integrated transceivers for connecting and communication purposes. Many CMOS installed devices are used in daily life for their noise absorption and low power consumption (in static mode).

RTC is a quite different miniature device that is used in personal computers, embedded mechanics and servers. RTCs are crucial to keeping up with the precise time. As the name suggests, RTC is all about time signals that control the digital electronic device. It is not like common clock hardware in our houses in a chip form! A module sends a specific sort of signalling to the BIOS to either start-up or picks up the time. RTC is fitted in devices such as GPS, CPUs and electronic devices that need time signals and stored information regarding how much time passes, with accuracy and precision.

The Combination of the Two Terms

RTC combines with a range of bytes of ROM (non-volatile battery), which as a whole is called CMOS. The chip is popular in electronic devices to boost the life of the battery and keep it going for several years, but most importantly, it has low power consumption, which controls the device's capacity. CMOS is a semiconductor, which means the chip is built out of metals that are both conductor and insulator to electricity on their own time. A semiconductor heated up becomes a conductor, and if it is at room temperature, it acts as an insulator. This feature of semiconductor plus oxidized metal coating on it makes it special with multiple features. RTC is within the CMOS that sends the time signals for the BIOS to start up.

The Bottom Line

Computer terms can be difficult to remember if you do not know of them, but the technology of today is all based upon the miniature circuits and chips that have eased large problems with small solutions. CMOS deals with only capacity that it lets through; hence saves so much space and runs for years. This was all about the difference between RTC and CMOS and their basic functions for today.


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