30 Sep
2020
30 Sep
'20
1:04 p.m.
I'm in the middle of working out the pinout for the power supply connector
on the MDP-1000. I'm aided somewhat by a set of test points on the
backplane, unfortunately the "+" and "-" symbols (in the solder mask
labels
next to the test points) are nearly indiscernible, so I'm trying to verify
that I'm not mixing up + and - 15V.
On the core memory boards are eight Motorola SC5330 IC's (datecodes from
early 1969), which have pins connected to both the + and - 15V lines -- if
I can find a datasheet I could pretty easily confirm which is which.
Trouble is I can't find anything on this chip. I've scanned through the
databooks on Bitsavers, no luck. Anyone have any ideas?
Here's a picture in case that helps at all:
https://1drv.ms/u/s!Aqb36sqnCIfMpIVXm5draSrWHGMzJg
- Josh
30 Sep
30 Sep
1:08 p.m.
The Motorola SC prefix means a custom or semicustom part. Good luck!
--
Will
On Wed, Sep 30, 2020 at 4:05 PM Josh Dersch via cctalk
<cctalk at classiccmp.org> wrote:
I'm in the middle of working out the pinout for the power supply connector
on the MDP-1000. I'm aided somewhat by a set of test points on the
backplane, unfortunately the "+" and "-" symbols (in the solder mask
labels
next to the test points) are nearly indiscernible, so I'm trying to verify
that I'm not mixing up + and - 15V.
On the core memory boards are eight Motorola SC5330 IC's (datecodes from
early 1969), which have pins connected to both the + and - 15V lines -- if
I can find a datasheet I could pretty easily confirm which is which.
Trouble is I can't find anything on this chip. I've scanned through the
databooks on Bitsavers, no luck. Anyone have any ideas?
Here's a picture in case that helps at all:
https://1drv.ms/u/s!Aqb36sqnCIfMpIVXm5draSrWHGMzJg
- Josh
2:40 p.m.
Josh wrote:
Would these potentially be the sense amp / comparators for the core? I
wonder if they were anything like:
https://datasheetspdf.com/pdf-file/1092342/Motorola/MC1711L/1
which might have a similar application and take +15 and -7 on L
package pins 11 and 4 respectively with ground on pin 12.
Being another Motorola design from what looks like a similar time
period, I wonder if there could be a similarity in pinouts by some
chance?
3:40 p.m.
On Wed, Sep 30, 2020 at 2:41 PM Gavin Scott via cctalk <
cctalk at classiccmp.org> wrote:
Josh wrote:
Would these potentially be the sense amp / comparators for the core? I
wonder if they were anything like:
https://datasheetspdf.com/pdf-file/1092342/Motorola/MC1711L/1
which might have a similar application and take +15 and -7 on L
package pins 11 and 4 respectively with ground on pin 12.
Being another Motorola design from what looks like a similar time
period, I wonder if there could be a similarity in pinouts by some
chance?
It's not an MC1711L based on that pinout. (But I suspect as you do that
it's part of the sense amp for the core). In particular Pin 1 of the IC is
connected to what I believe to be +15V. (It's also hard to tell what pin 1
is, since there's no orientation marker on these... ) Ground is pin 10. I
suspect -15V is pin 7.
- Josh
7:48 p.m.
On 9/30/2020 3:40 PM, Josh Dersch via cctalk wrote:
On Wed, Sep 30, 2020 at 2:41 PM Gavin Scott via cctalk
<
cctalk at classiccmp.org> wrote:
That pinout sounds like the Motorola MC1440 sense amp though the
voltages are different.
Bob
--
Vintage computers and electronics
www.dvq.com
www.tekmuseum.com
www.decmuseum.org
Josh wrote:
Would these potentially be the
sense amp / comparators for the core? I
wonder if they were anything like:
https://datasheetspdf.com/pdf-file/1092342/Motorola/MC1711L/1
which might have a similar application and take +15 and -7 on L
package pins 11 and 4 respectively with ground on pin 12.
Being another Motorola design from what looks like a similar time
period, I wonder if there could be a similarity in pinouts by some
chance?
It's not an MC1711L based on that pinout. (But I suspect as you do that
it's part of the sense amp for the core). In particular Pin 1 of the IC is
connected to what I believe to be +15V. (It's also hard to tell what pin 1
is, since there's no orientation marker on these... ) Ground is pin 10. I
suspect -15V is pin 7.
- Josh
2 Oct
2 Oct
12:52 a.m.
On Wed, Sep 30, 2020 at 7:48 PM Bob Rosenbloom via cctalk <
cctalk at classiccmp.org> wrote:
On 9/30/2020 3:40 PM, Josh Dersch via cctalk wrote:
Thanks, Bob! That does seem to be the same pinout, at least for the
power/ground. I think I've managed to convince myself of the correct
pinout for the power connector on this thing. I have a suitable supply and
connector on their way...
- Josh
On Wed, Sep 30, 2020 at 2:41 PM Gavin Scott via
cctalk <
cctalk at classiccmp.org> wrote:
is
Josh wrote:
Would these potentially be the
sense amp / comparators for the core? I
wonder if they were anything like:
https://datasheetspdf.com/pdf-file/1092342/Motorola/MC1711L/1
which might have a similar application and take +15 and -7 on L
package pins 11 and 4 respectively with ground on pin 12.
Being another Motorola design from what looks like a similar time
period, I wonder if there could be a similarity in pinouts by some
chance?
It's not an MC1711L based on that pinout. (But I suspect as you do that
it's part of the sense amp for the core). In particular Pin 1 of the IC connected to what I believe to be +15V.
(It's also hard to tell what
pin 1
is, since there's no orientation marker on
these... ) Ground is pin
10. I
suspect -15V is pin 7.
- Josh
That pinout sounds like the Motorola MC1440 sense amp though the
voltages are different.
1309
days inactive
1311
days old
5 comments
4 participants
participants (4)
-
bobalan＠sbcglobal.net -
derschjo＠gmail.com -
gavin＠learn.bio -
wdonzelli＠gmail.com