SN74LS168

SN74LS168 BCD DECADE 16 BINARY SYNCHRONOUS BI-DIRECTIONAL COUNTERS The SN54 / 74LS168 is a fully synchronous 4-stage up/down counter featuring a preset capability for programmable operation, carry lookahead for easy cascading and a U / D input to control the direction of counting. The SN54/ 74LS168 counts in a BCD decade (8, 4, 2, 1) sequence. All state changes, whether in counting or parallel loading, are initiated by the LOW-to-HIGH transition of the clock. Low Power Dissipation 100 mW Typical High-Speed Count Frequency 30 MHz Typical Fully Synchronous Operation Full Carry Lookahead for Easy Cascading Single Up / Down Control Input Positive Edge-Trigger Operation Input Clamp Diodes Limit High-Speed Termination Effects http://onsemi.com BCD DECADE 16 BINARY SYNCHRONOUS BI-DIRECTIONAL COUNTERS LOW POWER SCHOTTKY 16 1 J SUFFIX CERAMIC CASE 620-09 CONNECTION DIAGRAM DIP (TOP VIEW) VCC TC Q0 Q1 Q2 Q3 CET PE 16 15 14 13 12 11 10 9 NOTE: The Flatpak version has the same pinouts (Connection Diagram) as the Dual In-Line Package. 123 4 56 78 U/D CP P0 P1 P2 P3 CEP GND PIN NAMES LOADING (Note a) HIGH LOW CEP CET CP PE U/D P0−P3 Q0−Q3 TC Count Enable Parallel (Active LOW) Input Count Enable Trickle (Active LOW) Input Clock Pulse (Active positive going edge) Input Parallel Enable (Active LOW) Input Up-Down Count Control Input Parallel Data Inputs Flip-Flop Outputs Terminal Count (Active LOW) Output 0.5 U.L. 1.0 U.L. 0.5 U.L. 0.5 U.L. 0.5 U.L. 0.5 U.L. 10 U....