SN74ALS563BNSR屬于集成電路（IC）的鎖存器。由美國(guó)德州儀器公司制造生產(chǎn)的SN74ALS563BNSR鎖存器鎖存器是類(lèi)似于觸發(fā)器的基本數(shù)字存儲(chǔ)設(shè)備，但是不同之處在于，在鎖存使能（或類(lèi)似命名）信號(hào)處于有效邏輯狀態(tài)的任何時(shí)間，保持的邏輯狀態(tài)都可以改變?！巴该鳌辨i存器還允許設(shè)備輸出在鎖存使能信號(hào)有效時(shí)反映輸入的當(dāng)前狀態(tài)，而相反的是，狀態(tài)僅在保持狀態(tài)已固定時(shí)改變。

3-State Buffer-Type Outputs Drive Bus

Lines Directly

Bus-Structured Pinout

description/ordering information

These 8-bit D-type transparent latches feature

3-state outputs designed specifically for driving

highly capacitive or relatively low-impedance

loads. They are particularly suitable for

implementing buffer registers, I/O ports,

bidirectional bus drivers, and working registers.

While the latch-enable (LE) input is high, the Q

outputs follow the complements of data (D) inputs.

When LE is taken low, the outputs are latched at

the inverse of the levels set up at the D inputs.

A buffered output-enable (OE) input places the

eight outputs in either a normal logic state (high or

low logic levels) or a high-impedance state. In the

high-impedance state, the outputs neither load

nor drive the bus lines significantly. The

high-impedance state and increased high logic

level provide the capability to drive bus lines

without interface or pullup components.

OE does not affect internal operations of the

latches. Old data can be retained or new data can

be entered while the outputs are in the

high-impedance state.