Yet another sad512d substitue question

Started by the dude, May 21, 2009, 03:06:11 AM

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the dude

I have a old dod 670 with a dead sad512d (8-pin). I've recently aquired a sad512 16-pin ic. The 16-pin sad512 is a single bbd. I've looked at both the datasheets and I'm unsure if I could wire the 16-pin sad to work with the 8 pin. Has anyone tried this with any amount of luck? or should I just keep on hunting down a 8-pin sad512d?

Mark Hammer

They're different.  The 16-pin 512 is simply an SAD-1024 with one half working; a bit like the old days of diskettes when there were double-sided and single-sided disks, and single-sided simply meant that only one side was guaranteed to work.  The 8-pin SAD512D is different in that it includes on-board circuitry to take a single-phase clock input (tick-tick-tick) and convert it to dual-phase (tick-tock-tick-tock).  Since it is based on a 512D, the 670 board will lack the requisite flip-flop circuit to provide those two complementary clock pulses.  You CAN provide that conversion yourself, but at this point, we're starting to move well past a mere chip replacement.

oldschoolanalog

Mystery lounge. No tables, chairs or waiters here. In fact, we're all quite alone.

Mark Hammer

I went straight to the Smallbear stocklist when the OP came up, but found no mention of any reticon chips anymore. :icon_sad:

oldschoolanalog

#4
Quote from: Mark Hammer on May 21, 2009, 04:59:03 PM
I went straight to the Smallbear stocklist when the OP came up, but found no mention of any reticon chips anymore. :icon_sad:
"Hen's teeth" status. Ugh.
Guess it's time to break out the 4013's & SAD512's or TDA1022's...
Mystery lounge. No tables, chairs or waiters here. In fact, we're all quite alone.

aziltz

Quote from: oldschoolanalog on May 21, 2009, 08:27:52 PM
Quote from: Mark Hammer on May 21, 2009, 04:59:03 PM
I went straight to the Smallbear stocklist when the OP came up, but found no mention of any reticon chips anymore. :icon_sad:
"Hen's teeth" status. Ugh.
Guess it's time to break out the 4013's & SAD512's or TDA1022's...

hens have teeth?  ???

mdh

At least we can mourn the loss while recalling this subtly humorous gem from the SAD512D data sheet: "Use grounded soldering irons, tools, and personnel when handling devices."  This is audio electronics, we ain't got no "grounded personnel!"

oldschoolanalog

Quotehens have teeth?  ???
About as many as there are SAD512D's readily available & cheap... :D
Quote from: mdh on May 21, 2009, 09:45:04 PM
This is audio electronics, we ain't got no "grounded personnel!"
:icon_lol: :icon_lol: :icon_lol:
And we don't need no stinkin' badges either!

Mystery lounge. No tables, chairs or waiters here. In fact, we're all quite alone.

Rylan

Sorry to zombify this once dead thread, but I just put in an RFQ on 20 sad512d's so if you are all still looking for them I should have a few extras soon. I'll put em up on ebay once I get em.