
4-229
FAST AND LS TTL DATA
8-BIT BIDIRECTIONAL
BINARY COUNTER (3-STATE)
The MC74F579 is a fully synchronous 8-stage up/down counter with multi-
plexed 3-state I/O ports for bus-oriented applications. It features a preset
capability for programmable operation, carry look-ahead for easy cascading
and a U/D input to control the direction of counting. All state changes, except
for the case of asynchronous reset, are initiated by the rising edge of the clock.
TC output is not recommended for use as a clock or asynchronous reset due
to the possibility of decoding spikes.
 Multiplexed 3-State I/O Ports For Bus-oriented Applications
 Built-In Cascading Carry Capability
 Count Frequency 115 MHz Typ
 Supply Current 100 mA Typ
 Fully Synchronous Operation
 U/D Pin to Control Direction of Counting
 Separate Pins for Master Reset and Synchronous Reset
 Center Power Pins to Reduce Effects of Package Inductance
 See F269 for 24-Pin Separate I/O Port Version
 See F779 for 16-Pin Version
 ESD Protection > 4000 Volts
PIN ASSIGNMENT
CEP CET VCC
18
17
16
15
14
13
1
2
3
4
5
6
7
20
19
8
MR
CP
SR
U/D
TC
PE
I/O0
I/O1I/O2
I/O3
GND I/O4 I/O5
9
10
I/O7
I/O6
12
11
CS
OE
MR
SR
CEP
CET
OE
TC
PE
CS
U/D
CP
I/O0I/O1I/O2I/O3I/O4I/O5I/O6
I/O7
18
17
11
1
2
3
4
5
6
7
8
9
15
20
19
13
12
14
LOGIC SYMBOL
GUARANTEED OPERATING RANGES
Symbol
Parameter
Min
Typ
Max
Unit
VCC
TA
Supply Voltage
4.5
5.0
5.5
V
°
C
Operating Ambient Temperature Range
0
25
70
IOH
Output Current — High
TC
–1.0
mA
I/On
TC
–3.0
IOL
Output Current — Low
20
mA
I/On
24
MC74F579
8-BIT BIDIRECTIONAL
BINARY COUNTER (3-STATE)
FAST
 SCHOTTKY TTL
ORDERING INFORMATION
MC74FXXXJ
MC74FXXXN
MC74FXXXDW
Ceramic
Plastic
SOIC
20
1
J SUFFIX
CERAMIC
CASE 732-03
20
1
N SUFFIX
PLASTIC
CASE 738-03
20
1
DW SUFFIX
SOIC
CASE 751D-03