SN74AHC74集成電路（IC）的觸發(fā)器規(guī)格書PDF中文資料

1 Features

? Operating range 2-V to 5.5-V VCC

? Latch-up performance exceeds 250 mA per JESD

17

? ESD protection exceeds JESD 22

– 2000-V Human-Body Model (A114-A)

– 200-V Machine Model (A115-A)

– 1000-V Charged-Device Model (C101)

2 Applications

? Convert a momentary switch to a toggle switch

? Hold a signal during controller reset

? Input slow edge-rate signals

? Operate in noisy environments

? Divide a clock signal by two

3 Description

The SNx4AHC74 dual positive-edge-triggered devices

are D-type flip-flops.

A low level at the preset (PRE) or clear (CLR) inputs

sets or resets the outputs, regardless of the levels

of the other inputs. When PRE and CLR are inactive

(high), data at the data (D) input meeting the setup

time requirements is transferred to the outputs on

the positive-going edge of the clock pulse. Clock

triggering occurs at a voltage level and is not directly

related to the rise time of the clock pulse. Following

the hold-time interval, data at the D input can be

changed without affecting the levels at the outputs.