CY74FCT191T_14 Datasheet, PDF (1/14 Pages) Texas Instruments – 4-BIT UP/DOWN BINARY COUNTER

CY74FCT191T
4-BIT UP/DOWN BINARY COUNTER
D Function, Pinout, and Drive Compatible
With FCT and F Logic
D Reduced V_OH (Typically = 3.3 V) Versions
of Equivalent FCT Functions
D Edge-Rate Control Circuitry for
Significantly Improved Noise
Characteristics
D I_off Supports Partial-Power-Down Mode
Operation
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)
D Matched Rise and Fall Times
D 64-mA Output Sink Current
32-mA Output Source Current
SCCS016A – MAY 1994 – REVISED SEPTEMBER 2001
Q OR SO PACKAGE
(TOP VIEW)
P_{1 1}
Q₁ 2
Q₀ 3
CE 4
U/D 5
Q₂ 6
Q₃ 7
GND 8
16 ^V_CC
15 P₀
14 CP
13 RC
12 TC
11 PL
10 P₂
9 P₃
description
The CY74FCT191T is a reversible modulo-16 binary counter, featuring synchronous counting and
asynchronous presetting. The preset allows the CY74FCT191T to be used in programmable dividers. The count
enable input, terminal count output, and ripple-clock output make possible a variety of methods of implementing
multiusage counters. In the counting modes, state changes are initiated by the rising edge of the clock.
This device is fully specified for partial-power-down applications using I_off. The I_off circuitry disables the outputs,
preventing damaging current backflow through the device when it is powered down.
NAME
CE
CP
P
PL
U/D
Q
RC
TC
PIN DESCRIPTION
DESCRIPTION
Count enable input (active low)
Clock pulse input (active rising edge)
Parallel data inputs
Asynchronous parallel load input (active low)
Up/down count control input
Flip-flop outputs
Ripple clock output (active low)
Terminal count output
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.
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Copyright  2001, Texas Instruments Incorporated
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