I am looking for a pinout or datasheet for a chip labelled M51976FP. It appears to be made by Mitsubishi, it's a SMPSU controller in a 20 pin SOIC package. I have the data on the M51977, which is similar (I think), but some pins are clearly different. Looking on datasheetarchiver and digchip didn't find anything. And a google search (as ever) found plenty of people who sould sell me 100000 of them, but nothing else). [It's uised in a PSU modile in an HP tape drive that I am working on, so it does have som relevance to classic computers0. Thanks in advance for any help -tony