Thank you for the information Mondo.
I¡¯ve been studying the battery backup circuit and the three 6264 memory chips, but I¡¯m unsure which transistors you¡¯re referring to? I can¡¯t see any? If you could point me in the right direction, that¡¯d be great.?
I shall measure the current draw of the battery tomorrow.
Cheers
Paul
toggle quoted message
Show quoted text
On 13 May 2023, at 21:15, Mondovermona <ipc.de@...> wrote:
?Hi Paul,
Sorry to hear.? This is not a problem with the battery, it is with the backup circuit or one or more of the memory chips itself.? When ?CMOS memory chips are coming into age, they start draining more current in their memory backup.?
To resolve, you might want to measure the backup current flowing from the battery.? It should be around 1uA (0.001 mAmps).? In any case if the current draw would drop significantly with the memory chips removed then at least one of them will
be faulty.? If the fault is not wirh the memory chips, then you are left with a faulty on board memory backup voltage circuit. Oftentimes it is one of the transistors therein.?
Good luck.?
In any case, before hampering with your valuable device, you should feel confident that your electronic and micromechanic skills are sufficiently developed.? Else, keep your fingers off. ?
Mondo?
--
?_
Dr. Hartmut Schwahn
72070 T¨¹bingen?
Telefon: +49 163 1631495
