SN54AC564, SN74AC564
OCTAL D-TYPE EDGE-TRIGGERED FLIP-FLOPS
WITH 3-STATE OUTPUTS

SCAS551A - NOVEMBER 1995 - REVISED MAY 1996

features

• 3-State Inverting Outputs Drive Bus Lines Directly
• Full Parallel Access for Loading
• Flow-Through Architecture to Optimize PCB Layout
• EPIC^TM (Enhanced-Performance Implanted CMOS) 1-m Process
• Package Options Include Plastic Small-Outline (DW), Shrink Small-Outline (DB), Thin Shrink Small-Outline (PW), Ceramic Chip Carriers (FK) and Flatpacks (W), and Standard Plastic (N) and Ceramic (J) DIPs

   

  EPIC is a trademark of Texas Instruments Incorporated.

description

The 'AC564 are octal D-type edge-triggered flip-flops that feature inverting 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.

On the positive transition of the clock (CLK) input, the Q\ outputs are set to the inverse logic levels set up at the data (D) inputs.

A buffered output-enable () input places the eight outputs in either a normal logic state (high or low logic levels) 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 increased drive provide the capability to drive bus lines without interface or pullup components.

does not affect internal operations of the flip-flops. Old data can be retained or new data can be entered while the outputs are in the high-impedance state.

The SN54AC564 is characterized for operation over the full military temperature range of -55°C to 125°C. The SN74AC564 is characterized for operation from -40°C to 85°C.