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CD54AC191 Datasheet, PDF (1/1 Pages) Texas Instruments – Presettable Synchronous 4-Bit Binary Up/Down Counter | |||
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SEMICONDUCTOR
June 1997
COMPLETE DATA SHEET
COMING SOON!
CD54AC191/3A
CD54ACT191/3A
Presettable Synchronous
4-Bit Binary Up/Down Counters
Description
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.
When an overï¬ow or underï¬ow 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.
The CD54AC191/3A and CD54ACT191/3A are supplied in
16-lead dual-in-line ceramic packages (F sufï¬x).
Functional Diagram
BINARY PRESET
P0 P1 P2 P3
15 1 10 9
ASYN. PARALLEL 11
LOAD ENABLE
CLOCK 14
UP/DOWN 5
COUNT 4
ENABLE
3 Q0
2 Q1
6 Q2
BINARY
OUTPUTS
7 Q3
12 TERMINAL
COUNT
13 RIPPLE CLOCK
ACT INPUT LOAD TABLE
INPUT
UNIT LOAD (NOTE 1)
P0 - P3, PL
0.75
CL, U/D, CE
0.85
NOTE:
1. Unit load is âICC limit speciï¬ed in DC Electrical Speciï¬cations
Table, e.g., 2.4mA Max at +25oC.
Absolute Maximum Ratings
DC Supply Voltage, VCC . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to +6V
DC Input Diode Current, IIK
For VI < -0.5V or VI > VCC + 0.5V . . . . . . . . . . . . . . . . . . . . . .±20mA
DC Output Diode Current, IOK
For VO < -0.5V or VO > VCC + 0.5V . . . . . . . . . . . . . . . . . . . . .±50mA
DC Output Source or Sink Current, Per Output Pin, IO
For VO > -0.5V or VO < VCC + 0.5V . . . . . . . . . . . . . . . . . . . . .±50mA
DC VCC or GND Current, ICC or IGND
For Up to 4 Outputs Per Device, Add ±25mA For Each
Additional Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .±100mA
Power Dissipation Per Package, PD
TA = -55oC to +100oC (Package F) . . . . . . . . . . . . . . . . . . 500mW
TA = +100oC to +125oC (Package F) . . . . . . . . Derate Linearly at
8mW/oC to 300mW
Operating Temperature Range, TA
Package Type F . . . . . . . . . . . . . . . . . . . . . . . . . . -55oC to +125oC
Storage Temperature, TSTG . . . . . . . . . . . . . . . . . . -65oC to +150oC
Lead Temperature (During Soldering)
At Distance 1/16in. ± 1/32in. (1.59mm ± 0.79mm)
From Case For 10s Max . . . . . . . . . . . . . . . . . . . . . . . . . . +265oC
Unit Inserted Into a PC Board (Min Thickness 1/16in., 1.59mm)
With Solder Contacting Lead Tips Only. . . . . . . . . . . . . . . +300oC
CAUTION: Stresses above those listed in âAbsolute Maximum Ratingsâ 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 speciï¬cation is not implied.
Recommended Operating Conditions
Supply Voltage Range, VCC
Unless Otherwise Speciï¬ed, All Voltages Referenced to GND
TA = Full Package Temperature Range
CD54AC Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.5V to 5.5V
CD54ACT Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.5V to 5.5V
DC Input or Output Voltage, VI, VO. . . . . . . . . . . . . . . . . . 0V to VCC
Operating Temperature, TA . . . . . . . . . . . . . . . . . . . -55oC to +125oC
Input Rise and Fall Slew Rate, dt/dv
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
CAUTION: These devices are sensitive to electrostatic discharge. Users should follow proper I.C. Handling Procedures.
Copyright © Harris Corporation 1994
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File Number 3896
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