Does anybody know of any cross reference for the old SK# to ECG or any other? I have three IC's with the #'s sk7609,sk7613 and sk7710 which I can find no mathing datasheets on them. I need to know the pin-outs and function of the chips so I can use them in circuits. I could really use some pdf's on them I had four that I could not identify but I found one cross part on NTE's website but that was all they had. I use top have an SK cross reference book but I must have lost it. Thanks if you can help!!!