MM54HC194

MM54HC194 MM74HC194 4-Bit Bidirectional Universal Shift Register November 1995 MM54HC194 MM74HC194 4-Bit Bidirectional Universal Shift Register General Description This 4-bit high speed bidirectional shift register utilizes advanced silicon-gate CMOS technology to achieve the low power consumption and high noise immunity of standard CMOS integrated circuits along with the ability to drive 10 LS-TTL loads This device operates at speeds similar to the equivalent low power Schottky part This bidirectional shift register is designed to incorporate virtually all of the features a system designer may want in a shift register It features parallel inputs parallel outputs right shift and left shift serial inputs operating mode control inputs and a direct overriding clear line The register has four distinct modes of operation PARALLEL (broadside) LOAD SHIFT RIGHT (in the direction QA toward QD) SHIFT LEFT INHIBIT CLOCK (do nothing) Synchronous parallel loading is accomplished by applying the four bits of data and taking both mode control inputs S0 and S1 high The data are loaded into their respective flip flops and appear at the outputs after the positive transition of the CLOCK input During loading serial data flow is inhibited Shift right is accomplished synchronously with the rising edge of the clock pulse when S0 is high and S1 is low Serial data for this mode is entered at the SHIFT RIGHT data input When S0 is low and S1 is high data shifts left synchronously and new data is ent...