MN3005 in MemoryMan

[Thomas P.]

I belive I read this question before but:
When I look at the schematic for the Deluxe Memory Man there are two MN3005's.
So far so confused since a MN3005 has a DIL14 package with just 8 leads the schematic shows 10(!) connections to one of them.
Can someone solve this riddle???

[Athin]

maybe some sort of error on your schem. Look at this one:
(http://www.fortunecity.com/tinpan/humperdinck/223/memory.gif)
the numbers around the 3005 are pin numbers of the chip. (though I don't think this solves your problem)

[Thomas P.]

Well, that's exactly the schem I was looking to. Note that the MN3005 is a DIL14 so the pins are 1,2 - 6,7 - 8,9 - 13,14 (the datasheet just marks them from 1 to 8, by the way)!
In this schem the MN3005 'A' has a pin 12 which I think doesn't exist. Same with 4 and 11. :?

MN3005 datasheet

[StephenGiles]

Yes, the package is the size of a 14 pin, but the pins are just in the 1,2,6,7,8,9,13 &14 positions with gaps in between. On my stripboard Boss delay this was very handy as I didn't have to cut the tracks for the copper strips which crossed where the gaps are.
Stephen

[Athin]

exactly - if a pin ain't there it doesn't mean it can't have it's own number :wink:

[Thomas P.]

Good, good, but that doesn't answer my question where pin12, 4 and 11 are. As I see it the chip doesn't have them so I concider the schematic as false...

[Athin]

you got me - the schem is probably wrong, well the pin numbers @ least - you'd have to find which is which by yourself.

[Thomas P.]

you got me - the schem is probably wrong, well the pin numbers @ least - you'd have to find which is which by yourself.

Finding out the hard way: :?  :idea:  :wink:

[Prive]

I started the same thread some months ago but nothing, i think that schem is with SAD1024 or something else.
The MN3005 is in a 16 pins format but just 8 pins are useable.

I'm waiting for R.G. or someone who knows about it to read this post to make some light.

Saludos, Marcelo.

[Thomas P.]

I started the same thread some months ago but nothing, i think that schem is with SAD1024 or something else.
The MN3005 is in a 16 pins format but just 8 pins are useable.

I'm waiting for R.G. or someone who knows about it to read this post to make some light.

Saludos, Marcelo.

I'm pretty sure that the deluxe memory man uses MN3008 but I'll check if the connections make sens with a SAD1024 - good idea, tough.
I really think there's a "don't clone the memory man" conspiracy going on  :wink:

[Mark Hammer]

The MN3005 has 8 pins that are in the same locations as pins 1, 2, 6, 7, 8, 9, 13, and 14 on a 14-pin DIP.  The reason why it is important  to call them by their location on a 14-pin chip rather than the number pin they are starting from the "first" one is that the manufacturer/builder is likely going to use a normal 14-pin socket for the chip, inwhich case all 14 pins will be sticking out on the copper side.  All traces and routing will need to be with reference to the pin number that is visible on the copper side, otherwise it would be too confusing.

The MN3005 was used for some releases of the Memory Man, and the SAD1024 was used for others.  The 1024-based units precede the MN3005-based units, historically.  The pins for the one chip do not correspond to the pins for the other.  To the best of my knowledge, there was never any release of the MM during the 70's through 90's that used MN3008's or 3208's.  The big change was going from a setup that required multiple BBD's and individual bias/balance trimpots to a setup that only needed one bias trimpot.  Saved a heap of production costs/time.  Given that the MN3008 and 3005 were released (and discontinued) at almost the same time, can't see any reason any manufacturer would use a pair of 2048-stagers instead of a single 4096-stager unless they absoutely had no choice.  At the moment, with BL3208's available, that may well be the current choice, but I can only suspect that without confirming it.

[Thomas P.]

The MN3005 has 8 pins that are in the same locations as pins 1, 2, 6, 7, 8, 9, 13, and 14 on a 14-pin DIP.  The reason why it is important  to call them by their location on a 14-pin chip rather than the number pin they are starting from the "first" one is that the manufacturer/builder is likely going to use a normal 14-pin socket for the chip, inwhich case all 14 pins will be sticking out on the copper side.  All traces and routing will need to be with reference to the pin number that is visible on the copper side, otherwise it would be too confusing.

The MN3005 was used for some releases of the Memory Man, and the SAD1024 was used for others.  The 1024-based units precede the MN3005-based units, historically.  The pins for the one chip do not correspond to the pins for the other.  To the best of my knowledge, there was never any release of the MM during the 70's through 90's that used MN3008's or 3208's.  The big change was going from a setup that required multiple BBD's and individual bias/balance trimpots to a setup that only needed one bias trimpot.  Saved a heap of production costs/time.  Given that the MN3008 and 3005 were released (and discontinued) at almost the same time, can't see any reason any manufacturer would use a pair of 2048-stagers instead of a single 4096-stager unless they absoutely had no choice.  At the moment, with BL3208's available, that may well be the current choice, but I can only suspect that without confirming it.

Thanks Mark!

I don't thought about that connections of the two BBD's could be equal, I just thought about the schematic to indicate a wrong BBD. Well my intention was to make a project out of this and therefor I have to be sure that the schematic is right. But so far it seems to be wrong.
It seems there was a misunderstanding since I knew about the DIL14 package and the indication of the locations and thought I made it clear.