Good old MN3007 Issue -yet again-

[Baran Ismen]

Hi everyone.

Got a couple of chorus pedals on my mind to build in time, CE-2 and Small Clone initially, yet both of these use MN3007. MN3101 for CE-2 is available locally but MN3007 is a big problem. With a sisterboard, MN3207 can be used I see, but voltage is a problem then.

For CE-2, I plan to follow the good old tonepad's layout, but it's so tight that I don't know how can I reroute it (if required) if I use this 3207 integration and hence do the voltage adjustment.

The weird thing is, their datasheets here and here do not show any difference on pinouts (or at least I couldn't detect)

Also MadBean suggests using 3007/3101 or 3207/3102 (which are both also locally available) combinations. Would I be safe if I use a 9.1v Zener for D7 on the tonepad layout?

Here s the layout,
Here is the sis' board.

[ElectricDruid]

The difference isn't in the pinout, but rather the supply voltage. One uses a positive supply and the other a negative supply. The negative supply is often worked-around by reversing the Vdd and Ground connections.

Also, can you read those datasheets? There are plenty of english ones around. Not Turkish though, sorry.

[Baran Ismen]

The difference isn't in the pinout, but rather the supply voltage. One uses a positive supply and the other a negative supply. The negative supply is often worked-around by reversing the Vdd and Ground connections.

Also, can you read those datasheets? There are plenty of english ones around. Not Turkish though, sorry.

I know enough English to read and understand Tom, that's a bit offensive I'm also aware of the inversion of GND & VDD swap for both chips, I'm now checking the Aion and PedalPCB's boards to see how they worked it out, and they put a simple jumper for different IC's, routing the 9v to GND or vice versa and that's all it seems. MN31xx does this internally it says, so the only difference is this I guess. AND using a 9v1 Zener indeed for the 3207.

[ElectricDruid]

I know enough English to read and understand Tom, that's a bit offensive

No offense intended! I know your english is extremely good. The link you posted took me to a datasheet in Chinese/Japanese (I don't even know enough of either to tell which writing is which!). The *diagrams* are ok, of course, but the rest of it was no good to me, which is why I asked whether you could read it - maybe you know Japanese?

I'm also aware of the inversion of GND & VDD swap for both chips, I'm now checking the Aion and PedalPCB's boards to see how they worked it out, and they put a simple jumper for different IC's, routing the 9v to GND or vice versa and that's all it seems. MN31xx does this internally it says, so the only difference is this I guess. AND using a 9v1 Zener indeed for the 3207.

If you know to look out for that Vdd/Ground swap, you're way ahead of most people, lol! That must be the commonest screw-up on these circuits, even if it is the most obvious.

[Baran Ismen]

I know enough English to read and understand Tom, that's a bit offensive

No offense intended! I know your english is extremely good. The link you posted took me to a datasheet in Chinese/Japanese (I don't even know enough of either to tell which writing is which!). The *diagrams* are ok, of course, but the rest of it was no good to me, which is why I asked whether you could read it - maybe you know Japanese?

I'm also aware of the inversion of GND & VDD swap for both chips, I'm now checking the Aion and PedalPCB's boards to see how they worked it out, and they put a simple jumper for different IC's, routing the 9v to GND or vice versa and that's all it seems. MN31xx does this internally it says, so the only difference is this I guess. AND using a 9v1 Zener indeed for the 3207.

If you know to look out for that Vdd/Ground swap, you're way ahead of most people, lol! That must be the commonest screw-up on these circuits, even if it is the most obvious.

Cheers much, Tom! My only concern is whether the 9v would stress the mn3207 a bit much as the upper limit seems 11v. But there are various applications by pedal producers following the same path, so i believe it wont do any harm with a 9v zener.

Time for drawing a new pcb for that indeed, as the only one is tonepad and it depends on the 3007, rerouting is hard also. God knows how will i be able to fit everything on single side lol.

[Yazoo]

One way to source MN3007s and MN3101s is to look on a well-known auction site for non-working chorus pedals if you are prepared to take the risk and can get them cheaply. I managed to do this recently. Otherwise they are either very expensive or fake. I've had two batches of fakes in the past.

[ElectricDruid]

Xvive are making MN3007 clones:

https://xvive.com/audio/category/chips/

I don't know whether they do the clock chips too (don't think so), but that's not the hard part in most cases!

It's possible that if you get working "original" MN3007's these days, they might be these clones with the original markings wiped and something more valuable printed on afterwards (like Panasonic/whatever).
It'd be extremely hard to tell electronically.
 

[Baran Ismen]

Xvive are making MN3007 clones:

https://xvive.com/audio/category/chips/

I don't know whether they do the clock chips too (don't think so), but that's not the hard part in most cases!

It's possible that if you get working "original" MN3007's these days, they might be these clones with the original markings wiped and something more valuable printed on afterwards (like Panasonic/whatever).
It'd be extremely hard to tell electronically.
 

Yea i saw that too, but redesigning the pedal for using 3207 will be less costly for me