How long do CMOS batteries last? Deaktop MB vs Laptop MB
How long do CMOS batteries last? Deaktop MB vs Laptop MB
It continues this way because even with the PC connected and the PSU in ON mode, the power supply provides 5V standby while the battery remains idle. I experienced hours of real operation. In devices like calculators and key fobs, the battery only activates when you press a button, and the power draw is minimal—just enough for a short radio or infrared signal, which explains their long life.
You can still approximate actual usage despite such short intervals. The real users' time serves as the standard reference. To track exact battery consumption, you’d need to measure it directly at each millisecond.
We use tools to track and reduce a device’s power use during different conditions (sleep, idle, regular use, high speed) and then estimate remaining life based on those readings. There are certain equations that can estimate battery energy from specifications like mAh and voltage along with discharge patterns. While I don’t remember them all, manufacturer datasheets often provide charts illustrating how long a battery would last if the device draws the same power or current. By looking at these graphs, you can predict how long your gadget might run based on its measured consumption. For instance, the CR2032 battery datasheet includes a graph for continuous discharge with a 15kΩ load, showing voltage drops and expected runtime—helping you estimate performance over time. Similar charts are available in other sheets, though they offer more detailed temperature effects. Larger batteries such as lithium or alkaline require more complex calculations, but the basic principle remains consistent.