HEF4557B Description
The HEF4557B is a static clocked serial shift register whose length may be programmed to be any number of bits between 1 and 64. The number of bits selected is equal to the sum of the subscripts of the enabled length control inputs (L1, L2, L4, L8, L16 and L32) plus one. Serial data may be selected from the DA or DB data inputs with the A/B select input.