Dallas chip
Dallas chip is a colloquial term for a type family, battery-backed clock modules (RTC for english Real Time Clock ) in computer systems, named after its US manufacturer, the former Dallas Semiconductor Corp. (Dallas, Texas), now a subsidiary of Maxim Integrated (San Jose, California). Other manufacturers supplied compatible replicas, such as B. the ODIN 12C887.
This type of real-time clock is rarely used today.
It is a clock component with a battery integrated in the housing. This ensures that the clock continues to run while the computer is switched off. In addition, the Dallas chip has a RAM which, when used in computers, contains the BIOS settings and is also supplied by this battery, see also CMOS RAM .
If this battery is empty, you have to replace the entire chip if it is still available. If it is not socketed , it must be unsoldered and then re- soldered - with the associated risk of damaging the chip or the motherboard .
Instead of replacing the component, as a solution at the do-it-yourself level, attempts can also be made to "save" it by opening the chip housing, separating the used battery from the chip and soldering a new one.
Due to the product life cycle , as with most IC types, the product life is limited, which means that many types are no longer available when the end of the battery life (around 10 years) is reached.
Web links
- Maxim product overview. Check “Battery + Crystal” under Features to limit the selection to battery-buffered clock modules.
- Conversion instructions from Markus Kauer
- Conversion instructions from Peter H. Wendt (English)