Hi,
Not sure what a TMM314 is and can¹t find any data sheets on it. Best to use
either a TC5514APL-3 or an HM6514 which I know from experience both work. I
am guessing that the device you use has the same addressing but made from
some material other than CMOS which might explain the over consumption.
Perhaps some others in the group might be able to say...
If you are having trouble getting the right part go and see Senso at Vintage
Planet (http://www.vintageplanet.nl) I know he usually keeps the TCs in
stock.
Cheers,
Andy
On 28/12/2009 20:39, "r_j_d_2.phila" <r_j_d_2.phila@yahoo.com> wrote:
>
>
>
>
>
> thanks andy.the IC i replaced #32 with is a TMM314APL-1. i was told this was a
> workable sub. is there a better one out there? thanks.
>
> --- In PolySix@yahoogroups.com <mailto:PolySix%40yahoogroups.com> , Andrew
> Jury <andy@...> wrote:
>> >
>> > Hi,
>> >
>> > Sounds like progress to me. I tried to get you a typical current reading >>
for
>> > the SRAM but couldn¹t measure anything. I then took a look at the data
>> sheet
>> > and found that the device draw 20uA max! A bit smaller than my DMM can
>> read!
>> > So under normal circumstances the having the SRAM in circuit should draw
>> > very little from the battery indeed. This is why a lithium cell should last
>> > well over 5 years in this application. If upon connecting Vdd of the chip
>> > the battery starts to run down then perhaps there could well be a problem.
>> > What is the exact SRAM in use you have there? It should be a Toshiba
>> > TC5514APL-3 which is a 1024 word x 4 bit device. Perhaps you are using an
>> > incorrect part with a higher current consumption. However, I doubt it, I >>
was
>> > be more inclined to a faulty device. Do let us all know!
>> >
>> > Cheers,
>> > Andy
>> >
>> >
>> >
>> >
>> >
>> > On 28/12/2009 15:13, "r_j_d_2.phila" <r_j_d_2.phila@...> wrote:
>> >
>>> > >
>>> > >
>>> > >
>>> > >
>>> > >
>>> > > ok, so i have new data: after removing the SRAM chip and leaving the
>>> machine
>>> > > off overnight, the battery RESTORED itself to about 2.8V! im assuming
>>> that's
>>> > > good.
>>> > >
>>> > > for the record, my RAM chip, IC32, had been damaged, so i had replaced
>>> it with
>>> > > a socket. i have popped the 367 board, and verified every trace on IC32,
and
>>> > > also inspected it for any traces bridging. it all tests 100%. i bought a
>>> > > replacement IC, but it might have been a pull.
>>> > >
>>> > > so, 2 questions:
>>> > > 1-could my RAM chip be pulling the battery down, but functioning
>>> correctly
>>> > > otherwise? the machine writes/saves/functions properly in the
>>> programming
>>> > > regard.
>>> > >
>>> > > 2-if so, does anyone have a lead on a good replacement chip? thanks-rj
>>> > >
>>> > > --- In PolySix@yahoogroups.com <mailto:PolySix%40yahoogroups.com>
>>> <mailto:PolySix%40yahoogroups.com> , Andrew
>>> > > Jury <andy@> wrote:
>>>>> > >> >
>>>>> > >> > ...and a Merry Xmas to you and everyone else in the group! If you
don¹t
>>>> > >> do¹
>>>>> > >> > Xmas then at least I hope you are enjoying a nice break...
>>>>> > >> >
>>>>> > >> > The battery is there to keep the supply running to the memory
>>>>> subsystem
>>>> > >> when
>>>>> > >> > the mains power is off, right! This means that pin 18 of IC32 and
>>>>> pin 14 of
>>>>> > >> > IC25 are presented with the battery supply. If you are using a non
>>>>> > >> > chargeable cell and you replaced R91 with a 1N4148 signal diode
>>>>> then make
>>>>> > >> > sure it is polarized correctly. That is with cathode (line) facing
>>>>> towards
>>>>> > >> > the cathode of D15. This allows the battery to supply the two ICs
in
>>>>> > >> > question whilst the supply is off but keeps it isolated (diode is
>>>>> reverse
>>>>> > >> > polarized) when on.
>>>>> > >> >
>>>>> > >> > You should also remove C40 which is now redundant. If you haven¹t
>>>>> done so
>>>>> > >> > then this could possibly be the cause of the problem, if the
>>>>> component is
>>>>> > >> > dried up and no longer working as originally intended. Also check
C36 to
>>>>> > >> > verify it is not causing a problem in circuit. You are also quite
>>>>> safe to
>>>>> > >> > remove this and power the circuit on whilst testing. Finally, lift
>>>>> pins 18
>>>>> > >> > and 14 as described again and see if that makes any difference to
>>>>> the load
>>>>> > >> > on the battery.
>>>>> > >> >
>>>>> > >> > If you are using a 3v lithium cell, such as a CR2032 then you
>>>>> should have
>>>>> > >> > about 3.1v offload and about 2.9-3.0v on load. The figures you sent
us do
>>>>> > >> > not describe a circuit which is working properly. Get soldering and
let us
>>>>> > >> > know what you find...
>>>>> > >> >
>>>>> > >> > Cheers,
>>>>> > >> > Andy
>>>>> > >> >
>>>>> > >> >
>>>>> > >> > On 26/12/2009 20:50, "r_j_d_2.phila" <r_j_d_2.phila@> wrote:
>>>>> > >> >
>>>>>>> > >>> > >
>>>>>>> > >>> > >
>>>>>>> > >>> > >
>>>>>>> > >>> > >
>>>>>>> > >>> > >
>>>>>>> > >>> > > greetings, all-happy holidays. got a P6 battery question, to
follow up
>>>>> > >>> on my
>>>>>>> > >>> > > draining battery issue:
>>>>>>> > >>> > >
>>>>>>> > >>> > > i've taken the 367 board out, and cleaned/checked all of the
traces
>>>>> > >>> around the
>>>>>>> > >>> > > battery area. i didnt see any resistance at a low reading
>>>>>>> level that
>>>>> > >>> looked
>>>>>>> > >>> > > abnormal. i installed a battery clip socket. now, here are my
battery
>>>>> > >>> readings
>>>>>>> > >>> > > for a brand-new battery:
>>>>>>> > >>> > >
>>>>>>> > >>> > > -OUT OF MACHINE=2.7V
>>>>>>> > >>> > > -IN MACHINE, MACHINE OFF=1.5V
>>>>>>> > >>> > > -IN MACHINE, MACHINE ON=2.4V
>>>>>>> > >>> > >
>>>>>>> > >>> > > does this look normal? i probably wont know for another day or
two if it
>>>>>>> > >>> > > drains, but wanted your feedback on if these readings sound
normal.
>>>>> > >>> thanks, rj
>>>>>>> > >>> > >
>>>>>>> > >>> > >
>>>>>>> > >>> > >
>>>>>>> > >>> > >
>>>>>>> > >>> > >
>>>>> > >> >
>>>>> > >> >
>>>>> > >> >
>>>>> > >> > [Non-text portions of this message have been removed]
>>>>> > >> >
>>> > >
>>> > >
>>> > >
>>> > >
>>> > >
>> >
>> >
>> >
>> > [Non-text portions of this message have been removed]
>> >
>
>
>
>
>
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