D Operating Voltage Range of 4.5 V to 5.5 V
D State-of-the-Art BiCMOS Design
Significantly Reduces ICCZ
D Full Parallel Access for Loading
SN54BCT573 . . . J OR W PACKAGE
SN74BCT573 . . . DW, N, OR NS PACKAGE
OCTAL TRANSPARENT D-TYPE LATCHES
WITH 3-STATE OUTPUTS
SCBS071B − AUGUST 1990 − REVISED MARCH 2003
D ESD Protection Exceeds JESD 22
− 2000-V Human-Body Model (A114-A)
− 200-V Machine Model (A115-A)
− 1000-V Charged-Device Model (C101)
SN54BCT573 . . . FK PACKAGE
3 2 1 20 19
9 10 11 12 13
These 8-bit latches feature 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.
The eight latches of the ’BCT573 devices are transparent D-type latches. While the latch-enable (LE) input is
high, the Q outputs follow the data (D) inputs. When the latch enable is taken low, the Q outputs are latched
at the logic levels that were set up at 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 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.
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.
OE does not affect 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.
PDIP − N
0°C to 70°C
SOIC − DW
Tape and reel
SOP − NS
Tape and reel SN74BCT573NSR
CDIP − J
−55°C to 125°C CFP − W
LCCC − FK
† Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are
available at www.ti.com/sc/package.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
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.
Copyright © 2003, Texas Instruments Incorporated
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.
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