Datasheet in PDF form for the HEF4093B, a CMOS logic part from the HEF4000 family, best known as a quad two-input NAND gate with Schmitt-trigger inputs. The 86.2 KB document should cover the pinout, logic function, supply range and electrical characteristics. Technicians use it to confirm pin assignments when probing a suspect gate, to check input thresholds and hysteresis, and to choose a valid substitute such as a CD4093 or HCF4093 when the original package is unavailable.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @cyberlanelectonik. Enginerys does not host this file.
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