CD54AC191/3A
CD54ACT191/3A
S E M I C O N D U C T O R
COMPLETE DATA SHEET
COMING SOON!
Presettable Synchronous
4-Bit Binary Up/Down Counters
June 1997
Description
Functional Diagram
BINARY PRESET
The CD54AC191/3A and CD54ACT191/3A are asynchro-
nously presettable binary up/down synchronous counters
that utilize the Harris Advanced CMOS Logic technology.
Presetting the counter to the number on preset data inputs
(P0-P3) is accomplished by setting LOW the asynchronous
parallel load input (PL). Counting occurs when PL is HIGH.
Count Enable (CE) is LOW, and the Up/Down (U/D) input is
either LOW for up-counting or HIGH for down-counting. The
counter is incremented or decremented synchronously with
the LOW-to-HIGH transition of the clock.
P0 P1 P2 P3
15
1
10
9
ASYN. PARALLEL
LOAD ENABLE
11
14
5
3
2
6
7
Q0
Q1
Q2
Q3
BINARY
OUTPUTS
CLOCK
When an overflow or underflow of the counter occurs, the
Terminal Count (TC) output, which is LOW during counting,
goes HIGH and remains HIGH for one clock cycle. This
output can be used for look-ahead carry in high-speed
cascading. The TC output also initiates the Ripple Clock
(RC) output which, normally HIGH, goes LOW and remains
LOW for the low-level portion of the clock pulse. These
counters can be cascaded using the Ripple Count output.
UP/DOWN
12 TERMINAL
COUNT
4
13
COUNT
ENABLE
RIPPLE CLOCK
ACT INPUT LOAD TABLE
INPUT
UNIT LOAD (NOTE 1)
The CD54AC191/3A and CD54ACT191/3A are supplied in
16-lead dual-in-line ceramic packages (F suffix).
P0 - P3, PL
CL, U/D, CE
0.75
0.85
NOTE:
1. Unit load is ∆I limit specified in DC Electrical Specifications
CC
o
Table, e.g., 2.4mA Max at +25 C.
Absolute Maximum Ratings
DC Supply Voltage, V . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to +6V
Power Dissipation Per Package, P
D
CC
o
o
DC Input Diode Current, I
T = -55 C to +100 C (Package F) . . . . . . . . . . . . . . . . . . 500mW
IK
A
o
o
For V < -0.5V or V > V + 0.5V . . . . . . . . . . . . . . . . . . . . . .±20mA
T = +100 C to +125 C (Package F) . . . . . . . . Derate Linearly at
I
I
CC
A
o
DC Output Diode Current, I
8mW/ C to 300mW
OK
For V < -0.5V or V > V + 0.5V. . . . . . . . . . . . . . . . . . . . .±50mA Operating Temperature Range, T
O
O
CC
A
o
o
DC Output Source or Sink Current, Per Output Pin, I
Package Type F. . . . . . . . . . . . . . . . . . . . . . . . . .-55 C to +125 C
O
o
o
For V > -0.5V or V < V + 0.5V. . . . . . . . . . . . . . . . . . . . .±50mA
Storage Temperature, T
. . . . . . . . . . . . . . . . . .-65 C to +150 C
O
O
CC
STG
DC V or GND Current, I or I
Lead Temperature (During Soldering)
CC
CC
GND
For Up to 4 Outputs Per Device, Add ±25mA For Each
Additional Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .±100mA
At Distance 1/16in. ± 1/32in. (1.59mm ± 0.79mm)
From Case For 10s Max . . . . . . . . . . . . . . . . . . . . . . . . . . +265 C
Unit Inserted Into a PC Board (Min Thickness 1/16in., 1.59mm)
o
o
With Solder Contacting Lead Tips Only. . . . . . . . . . . . . . . +300 C
CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation
of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
Recommended Operating Conditions
o
o
Supply Voltage Range, V
Operating Temperature, T . . . . . . . . . . . . . . . . . . .-55 C to +125 C
CC
A
Unless Otherwise Specified, All Voltages Referenced to GND
Input Rise and Fall Slew Rate, dt/dv
T = Full Package Temperature Range
CD54AC Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.5V to 5.5V
CD54ACT Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.5V to 5.5V
at 1.5V to 3V (AC Types) . . . . . . . . . . . . . . . . . . . 0ns/V to 50ns/V
at 3.6V to 5.5V (AC Types) . . . . . . . . . . . . . . . . . 0ns/V to 20ns/V
at 4.5V to 5.5V (AC Types) . . . . . . . . . . . . . . . . . 0ns/V to 10ns/V
A
DC Input or Output Voltage, V , V . . . . . . . . . . . . . . . . . . 0V to V
CC
I
O
CAUTION: These devices are sensitive to electrostatic discharge. Users should follow proper I.C. Handling Procedures.
File Number 3896
Copyright © Harris Corporation 1994
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