According to the datasheet of the Reticon R5106 BBD, this chip “is an improved pin-compatible replacement for the SAD512D (do not confuse with the 16pin SAD512)”. The datasheet of the newer RD5106A doesn’t mention this compatibility. I was curious to know if they were interchangeable.
The pinout is almost identical with one exception: SAD512D has two outputs (an even and an odd) but R5106 has only one output and left the remaining pin (3) unconnected (picture bellow).
It took some time to find devices that use these chips. I eventually bought a MXR Micro Chorus with a SAD512D and a MXR Stereo Flanger with a R5106.
The electric characteristics of SAD512D and R5106 are very similar and doesn’t seem to be a risk swapping them in the two pedals. The values in the table below are from the original datasheets. I also included the newer RD510xA specs because I also want to try swapping them with both SAD512D and R5106. They also have approximate electric values and the same pinout as the R5106. The SAD512D datasheet shows 10V as minimum voltage but MXR micro chorus is powered by a 9V battery…
Well: bad news. R5106 don’t work in the place of the SAD512D and the other way around also don’t work. But when I tried using RD5106A and RD5107A to replace R5106, both worked perfectly. I’ll do some more testing and bias adjusting and then update this post…