Well I've received my M48T86PC1 Cmos Clock Lithium Battery as a gift from China, according to the custom declaration. It is an ST microelectronics part, my concern is the manufacturing date. The Chip is labeled as below,
M48T86PC1 Real-Time Clock Contains Lithium Cell 990SN VH MYS 99 1033 WO723Y
I hate seeing all the 99's, any one know how to read a date code for ST microelectronics.
Another route, any chance I could measure the battery voltage? The pinout is here but I don't know if the battery voltage is present on any pin.
I wish I would have done a little more research before ordering this chip, I'm now finding a replacement chip DS12887. With chips available from Mouser and Digikey, so I expect recent manufacture.
Maybe I'll be lucky and this chip will be found to be recent manufacture. I only want to replace the chip once on the motherboard, a second time might be pressing my luck. I'll order a second newer chip if it seems appropriate.
Your help appreciated, Mikek