SN74ALVCH16721
3.3-V 20-BIT FLIP-FLOP
WITH 3-STATE OUTPUTS

SCES052A - JULY 1995 - REVISED NOVEMBER 1996

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of TexasInstruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

features

• Member of the Texas Instruments Widebus^TM Family
• EPIC^TM (Enhanced-Performance Implanted CMOS) Submicron Process
• ESD Protection Exceeds 2000 V Per MIL-STD-883, Method 3015; Exceeds200 V Using Machine Model (C = 200 pF, R = 0)
• Latch-Up Performance Exceeds 250 mA Per JEDEC Standard JESD-17
• Bus Hold on Data Inputs Eliminates the Need for External Pullup/Pulldown Resistors
• Package Options Include Plastic 300-mil Shrink Small-Outline (DL) and Thin Shrink Small-Outline (DGG) Packages

   

  EPIC and Widebus are trademarks of Texas Instruments Incorporated.

description

This 20-bit flip-flop is designed specifically for 2.3-V to 3.6-V V_CC operation.

The SN74ALVCH16721 20 flip-flops are edge-triggered D-type flip-flops with qualified clock storage. On the positive transition of the clock (CLK) input, the device provides true data at the Q outputs if the clock-enable () input is low. If is high, no data is stored.

A buffered output-enable () input places the 20 outputs in either a normal logic state (high or low) 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. 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.

To ensure the high-impedance state during power up or power down, should be tied to V_CC through a pullup resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.

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

The SN74ALVCH16721 is available in TI's shrink small-outline (DL) and thin shrink small-outline (DGG) packages, which provide twice the I/O pin count and functionality of standard small-outline packages in the same printed circuit board area.

The SN74ALVCH16721 is characterized for operation from -40°C to 85°C.