[sdiy] DW8000 CMOS ram

[harrybissell at copper.net]

I have the Angel City board as well...

I think that if you have the mod, the battery on that board
is the only one that is active...

There is a select line that is "mini-hooked"
to a point, I forget what that doea... check that ???

Another trick is to replace the diodes in a battery
backup with shottky diodes, thus improving the
retention voltage a LOT.  They are more leaky in the
reverse direction at high temps... but I've never had a problem.
Maybe in "Death Valley" ....

H^) harry


>
>
>
>---- Original Message ----
>From: tshire at charter.net
>To: synth-diy at dropmix.xs4all.nl, harrybissell at copper.net
>Subject: Re: [sdiy] DW8000 CMOS ram
>Date: Fri, 12 Jan 2007 16:07:35 -0500
>
>>I'd wonder if the 2.6V is too low
>>for data retention ???   Is the
>>backup battery good ???
>>
>>H^) harry
>>
>>
>>The battery I put in was a pull, but shows just over 3v no load. The
>batt v
>>goes through a diode junction before hitting pin 24 on the 6116.
>This also
>>has that "angel city" expansion mod. Maybe that's causing problems.
>My next
>>guess would be that the switching from operate to stby for that ram
>is not
>>fast enough. I'll scope the transition and see what's happening.