HD74ALVCH16820

3.3-V 10-bit Flip Flops with Dual Outputs

ADE-205-170B (Z)

3rd. Edition

December 1999

Description

The flip flops of the HD74ALVCH16820 are edge triggered D-type flip flops. On the positive transition of

the clock (CLK) input, the device provides 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 level) 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 input does not affect the internal operation of the flip flops. Old data

can be retained or new data can be entered while the outputs are in the high impedance state. Active bus

hold circuitry is provided to hold unused or floating data inputs at a valid logic level.

Features

• V

• Typical V

• Typical V

• High output current ±24 mA (@V

• Bus hold on data inputs eliminates the need for external pullup / pulldown resistors