器件名称:
DM74S74
功能描述:
Dual Positive-Edge-Triggered D Flip-Flops with Preset, Clear, and Complementary Outputs
文件大小:
50.7KB 共5页
简 介:
DM74S74 Dual Positive-Edge-Triggered D Flip-Flops with Preset, Clear, and Complementary Outputs August 1986 Revised April 2000 DM74S74 Dual Positive-Edge-Triggered D Flip-Flops with Preset, Clear, and Complementary Outputs General Description This device contains two independent positive-edge-triggered D flip-flops with complementary outputs. The information on the D input is accepted by the flip-flops on the positive going edge of the clock pulse. The triggering occurs at a voltage level and is not directly related to the transition time of the rising edge of the clock. The data on the D input may be changed while the clock is LOW or HIGH without affecting the outputs as long as setup and hold times are not violated. A low logic level on the preset or clear inputs will set or reset the outputs regardless of the logic levels of the other inputs. Ordering Code: Order Number DM74S74M DM74S74N Package Number M14A N14A Package Description 14-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-120, 0.150 Narrow 14-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code. Connection Diagram Function Table Inputs PR L H L H H H CLR H L L H H H CLK X X X ↑ ↑ L D X X X H L X Q H L H* H L Q0 Outputs Q L H H* L H Q0 H = HIGH Logic Level X = Either LOW or HIGH Logic Level L = LOW Logic Level ↑ = Positive-going Transition * = This configuration is nonstable; that is……