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State-of-the-Art EPIC-IIBE BiCMOS Design
Significantly Reduces Power Dissipation
Latch-Up Performance Exceeds 500 mA Per
JEDEC Standard JESD-17
Typical VOLP (Output Ground Bounce) < 1 V
at VCC = 5 V, TA = 25°C
High-Drive Outputs (–32-mA IOH, 64-mA IOL)
ESD Protection Exceeds 2000 V Per
MIL-STD-883, Method 3015; Exceeds 200 V
Using Machine Model (C = 200 pF, R = 0)
Package Options Include Plastic
Small-Outline (DW), Shrink Small-Outline
(DB), and Thin Shrink Small-Outline (PW)
Packages, Ceramic Chip Carriers (FK),
Plastic (N) and Ceramic (J) DIPs, and
Ceramic Flat (W) Package
description
These 8-bit flip-flops 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 flip-flops of the SN54ABT374 and
SN74ABT374A are edge-triggered D-type
flip-flops. On the positive transition of the clock
(CLK) input, the Q outputs are set to the logic
levels set up at the data (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 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 does not affect internal operations of the flip-flop. 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.
The SN54ABT374 is characterized for operation over the full military temperature range of –55°C to 125°C. The
SN74ABT374A is characterized for operation from –40°C to 85°C.
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