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Hello
this is used in Yamaha BK20A1 organ made in 70s by hitachi
16 pin package using a sandwich of 2 pieces of ceramic,
the circuit shows power rail of -9 and -26v
and describes it as 6 dividers in 1 package
looking at some organ forums say lm3211 but i dont agree
can anyone find a replacement or should i just make some flip flop circuits
I saw a circuit diagram for a different Yamaha organ online:
From that, it looks like just six independent divide-by-2 instances inside each chip.
You'd need to measure the voltage at the input, to see if the signals are 5V logic, or something completely different.
You could use three 74HC74 ICs, which are dual D-type flip-flops which can be configured to divide by 2. You'd need output circuitry (either transistors., or even op-amps) to level shift because there's a fair chance the levels might not be anything normal.
In summary if one of these ICs is faulty then you'll likely need a custom adapter PCB made up with the circuitry mentioned.
You could use programmable logic, but I don't think it will save much space, since you still will need the output driver circuitry to level-shift.
I doubt there's any non-obsolete second-source for this obscure IC, because there's just no requirement for such functionality nowadays.
In looking further in the limited set of Hitachi parts that found, the HD31xx parts are MOS devices, Here is a screen shot of a HD3107 from Hitachi:
They are showing VGG values of 24V +/- 10% and VDD values 14V +/- 10%, so these are in the ballpark of what you are seeing.
