I'm designing a replacement for an old Western Electric logic part that used mid 1970s TTL in an unusual interface application. I must match the input V/I curve of this old logic part. A 74F151 is the most likely candidate as the replacement part, but the input current (IIL)on a recently purchased device is far lower than I expected. I suspect this is due to the series B "improvement". Does anyone have a transistor level schematic of the basic gates used in the 74FxxB devices, specifically, the D0-D7 inputs on this 74F151B?
Thanks,
Tom Bowers, PVH Engineering
