SN74ABT821ADW屬于集成電路（IC）的觸發(fā)器。由美國德州儀器公司制造生產的SN74ABT821ADW觸發(fā)器觸發(fā)器是能夠存儲單個邏輯狀態(tài)或信息“位”的基本數字存儲器件。這些器件至少有兩個輸入；一個或多個用于傳遞要存儲的數據，另一個用于指示存儲該數據的時間點。不同的觸發(fā)器類型，例如 D（延遲）、SR（置位復位）和 JK，對提供給其輸入的信號有不同的響應，可用于實現不同的邏輯功能。這些器件與鎖存器的不同之處在于它們是邊緣敏感器件，其保持的邏輯狀態(tài)僅在接收到有效時鐘信號時才會改變。

State-of-the-Art EPIC-IIBE BiCMOS Design

Significantly Reduces Power Dissipation

ESD Protection Exceeds 2000 V Per

MIL-STD-883, Method 3015

Latch-Up Performance Exceeds 500 mA Per

JEDEC Standard JESD-17

Typical VOLP (Output Ground Bounce) < 1 V

at VCC = 5 V, TA = 25°C

High-Impedance State During Power Up

and Power Down

High-Drive Outputs (–32-mA IOH, 64-mA IOL)

Package Options Include Plastic

Small-Outline (DW) and Shrink

Small-Outline (DB) Packages, Ceramic Chip

Carriers (FK), Ceramic Flat (W) Package,

and Plastic (NT) and Ceramic (JT) DIPs

description

These 10-bit flip-flops feature 3-state outputs

designed specifically for driving highly capacitive

or relatively low-impedance loads. They are

particularly suitable for implementing wider buffer

registers, I/O ports, bidirectional bus drivers with

parity, and working registers.

The ten flip-flops are edge-triggered D-type

flip-flops. On the positive transition of the clock

(CLK) input, the devices provide true data at the

Q outputs.

A buffered output-enable (OE) input can be used

to place the ten 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 drive provide the capability to drive bus

lines without need for interface or pullup

components.

OE does not affect the internal operations of the latch. Previously stored data can be retained or new data can

be entered while the outputs are in the high-impedance state.

When VCC is between 0 and 2.1 V, the device is in the high-impedance state during power up or power down.

However, to ensure the high-impedance state above 2.1 V, OE should be tied to VCC through a pullup resistor;

the minimum value of the resistor is determined by the current-sinking capability of the driver.

The SN54ABT821 is characterized for operation over the full military temperature range of –55°C to 125°C. The

SN74ABT821A is characterized for operation from –40°C to 85°C.