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Unformatted text preview: the logic diagram and function table. The registers are fully synchronous. The “194” design has special features which increase the range of application. The synchronous operation of the device is determined by the mode select inputs (S0, S1). As shown in the mode select table, data can be entered QUICK REFERENCE DATA GND = 0 V; Tamb = 25 °C; tr = tf = 6 ns 74HC/HCT194 and shifted from left to right (Q0 → Q1 → Q2, etc.) or, right to left (Q3 → Q2 → Q1, etc.) or parallel data can be entered, loading all 4 bits of the register simultaneously. When both S0 and S1 are LOW, existing data is retained in a hold (“do nothing”) mode. The first and last stages provide D-type serial data inputs (DSR, DSL) to allow multistage shift right or shift left data transfers without interfering with parallel load operation. Mode select and data inputs are edge-triggered, responding only to the LOW-to-HIGH transition of the clock (CP). Therefore, the only timing restriction is that the mode control and selected data inputs must be stable one set...
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This note was uploaded on 03/21/2012 for the course COMP EE357 taught by Professor Vanloon during the Fall '10 term at Mohawk College.
- Fall '10