X68000 Compact battery replacement

Started by costa, December 20, 2014, 09:43:44 PM

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Hi guys.

The batteries on X68000 Compact needs replacement? Or should it be replaced?
Model is Panasonic ????UL1220.

1. I am supposing it is not a rechargeable battery.
2. I know it probably has not leak problems
3. ... but I am concerned that it is probably dead - has not charge anymore.
4. If it should be replaced, can I use CR2032? I have been using these for other models.
5. This question also applies to XVI tower models, by the way, although the batteries differ



The batteries in the X68000 Compact models are Rechargeable ones (just like with the X68030 models), Witch means they are only recharable 1xxx amount of times before they will not hold much of or hardly any charge at all.

It all depends on how many charge cycles the battery has reseaved, if your X68k Compact has been used a lot, this this will most likely be the case.

A good way of testing to see if the battery will hold a charge, is to launch the Switch program and set some values, for example: set the SRAM setting to ether RAMDISK or PROGRAM and then make a note of it and then shut your X68k down and leave it plugged in for an hour or two, then unplug it and leave it for a while.
after that, plug it in again and check the setting under the switch program. it if has returned to the no_use default, then most certainly the battery is no longer holding any charge.

The battery's in the XVI Tower models are NOT rechargeable ones, so you could in theory, replace it with a coin cell holder if you wanted to.


Great info H68K, thanks
I was thinking that the Compact battery was not rechargeable... not easy to find info on these things.

I am systematically replacing NI-CD batteries by CR2032, using a diode to block the recharging to the battery.
If the Compact battery is dead, I suppose I can use the same technique on it?


Yes, you could in theory do the same to your X68k Compact. But you'd have to put in a diode or something to prevent the battery from being charged when it's running or in standby, normal lithium cell batteries DO NOT like having a charge put into them.

You'll also have to take note of the limited space available when choosing and positioning the coin cell holder, as there's not much clearance between the motherboard and the bottom part of the plastic chassis it's held into.


Ive been able to find direct original replacements for the stock battery.  That is what Ive typically done on compacts.


Well, you can use a common CR2032 (like I do for all my japanese machines, FM-TOWNS, SHarp and NEC) but you have to built a small circuit to adapt it.According datasheet CR2032 can receive a charge current up to 10mA so you have to sue two diodes (1N4007 do the job or other one with low reverse leakage current) to prevent battery rechargement and a resistor to limit the current in case of diode failure.This is the scheme to follow (at the end of PDF document):


The choose of the resistor value depends from this formula (first Ohm's law):


So, let's say  5V is the rechargement  supplied voltage and a 3V battery is used  (like the CR2032 which, like I said,  can receive a maximum charge current of 10mA):

R=V(5V - 3V) / 10=0,2

then  0,2 X1000=200   

so 200 Ohm will be the right resistor value in case of use of a CR2032 replacement when the supplied voltage is 5V (it may differs, for example on my PC9821 machine is 3.50v so 0.50 / 10= 50 Ohm)


My compact has already a bettery with Coin cell holder in it.

Can i just replace the battery with a new ore used one or not?



I know this is an old topic... But I just wanted to say that the battery is named: "Panasonic VL1220".
Here's an image of the compact mother board containg the battery:
Here's a website regarding the battery:

and if you are swedish, you can order the battery for $6 or so (excl shipping):