page_title: Real-time clock
section_title: Power source
hierarchical_section_title: Real-time clock / Power source
caption_attribution_description: English: Inside the Real-time clock IC
context_page_description: A real-time clock is a computer clock that keeps track of the current time.
  Although the term often refers to the devices in personal computers, servers and embedded systems, RTCs are present in almost any electronic device which needs to keep accurate time.
context_section_description: RTCs often have an alternate source of power, so they can continue to keep time while the primary source of power is off or unavailable. This alternate source of power is normally a lithium battery in older systems, but some newer systems use a supercapacitor, because they are rechargeable and can be soldered. The alternate power source can also supply power to battery backed RAM.
caption: Lithium battery inside the real-time clock IC
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