Changed an NES Battery, saves remained?

[ReddMcKnight]

I just changed the battery in my Ultima NES Cartridge, and when I booted it up to test it, my Saved Game was still there. Does this mean I did something wrong, or is this normal?

[lwcook]

You did fine. If you changed the batteries quick enough, then your saves could still be there.

[KDub]

Yep the saved up power in the ram could have stayed and kept the saves if you were fast.

[Zing]

It requires a surprisingly minute amount of charge to maintain the state of the memory.

[SnowKitty]

some types of ram will hold data without power for a little while. this is why you can change the suicide batteries on CPS2 games without a helper battery if you do it in less than a half hour to 45 minutes (i've heard they holdit for up to an hoursometimes though) you can NOT do that on CPS3 or protected CPS1 boards though because they die as soon as power is removed from the ram