OCTAL TRANSPARENT D-TYPE LATCHES
WITH 3-STATE OUTPUTS
SCLS454A – FEBRUARY 2001 – REVISED APRIL 2003
D 2-V to 6-V VCC Operation
D Wide Operating Temperature Range of
–55°C to 125°C
D 3-State Outputs Directly Drive Bus Lines
D Balanced Propagation Delays and
D Bus Driver Outputs Drive Up To 15 LS-TTL
D Significant Power Reduction Compared to
LS-TTL Logic ICs
CD54HC573 . . . F PACKAGE
CD74HC573 . . . E OR M PACKAGE
The ’HC573 devices are octal transparent D-type
latches designed for 2-V to 6-V VCC operation.
When the latch-enable (LE) input is high, the Q outputs follow the data (D) inputs. When LE is low, the Q outputs
are latched at the logic levels of the D inputs.
A buffered output-enable (OE) input can be used to place the eight outputs in either a normal logic state (high
or low) 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.
OE does not affect the 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.
To ensure the high-impedance state during power up or power down, 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.
PDIP – E Tube
–55°C to 125°C SOIC – M
Tape and reel
CDIP – F Tube
† Package drawings, standard packing quantities, thermal data, symbolization, and PCB design
guidelines are available at www.ti.com/sc/package.
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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
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On products compliant to MIL-PRF-38535, all parameters are tested
unless otherwise noted. On all other products, production
processing does not necessarily include testing of all parameters.