HEF4894B

The HEF4894B is a 12 stage serial shift register having a storage latch associated with each stage for strobing data from the serial input to parallel LED driver outputs O₀ to O₁₁. Data is shifted on positive-going clock transitions. The data in each shift register stage is transferred to the storage register when the strobe (STR) input is HIGH. Data in the storage register appears at the outputs whenever the output enable (EO) signal is HIGH.

Two serial outputs (O_s and O_s') are available for cascading a number of HEF4894B devices. Data is available at O_s on positive-going clock edges to allow high-speed operation in cascaded systems in which the clock rise time is fast. The same serial information is available at O_s' on the next negative-going clock edge and provides cascading HEF4894B devices when the clock rise time is slow.