SCLS244J October 1995 – December 2014 SN54AHC574 , SN74AHC574
PRODUCTION DATA.
请参考 PDF 数据表获取器件具体的封装图。
The SNx4AHC574 devices are octal edge-triggered D-type flip-flops that feature 3-state outputs designed specifically for driving highly capacitive or relatively low-impedance loads. These devices are particularly suitable for implementing buffer registers, I/O ports, bidirectional bus drivers, and working registers.
On the positive transition of the clock (CLK) input, the Q outputs are set to the logic levels of the data (D) inputs.
The states of the Q outputs are not predictable until the first valid clock.
A buffered output-enable (OE) input can be used to place the eight outputs in either a normal logic state (high or low) or the high-impedance state. In the high-impedance state, the outputs neither load nor drive the bus lines significantly. The high-impedance state and the increased drive provide the capability to drive bus lines without interface or pull-up components.
INPUTS | OUTPUT Q |
||
---|---|---|---|
OE | CLK | D | |
L | ↑ | H | H |
L | ↑ | L | L |
L | H or L | X | Q0 |
H | X | X | Z |