INTEGRATED CIRCUITS
74F1779
8-bit bidirectional binary counter (-State)
Product specification
IC15 Data Handbook
1989 Apr 06
Philips Semiconductors Product specification
74F17798-bit bidirectional binary counter (3-State)
FEA TURES
•Multiplexed 3-State I/O ports for bus oriented applications
•Built-in look-ahead carry capability
•Center power pins to reduce effects of package inductance
•Count frequency 145MHz typical
•Supply current 90mA typical
•See 74F269 for 24-pin separate I/O port version
•See 74F579 for 20-pin version
•See 74F779 for 16-pin version with abbreviated function table
DESCRIPTION
The 74F1779 is a fully synchronous 8-stage up/down counter with
multiplexed 3-State I/O ports for bus-oriented applications. All
control functions (hold, count up, count down, synchronous load) are
controlled by two mode pins (S0, S1). The device also features carry
look-ahead for easy cascading. All state changes are initiated by the
rising edge of the clock. When CET
held in their current state and TC
recommended for use as a clock or asynchronous reset due to the
possibility of decoding spikes.
The 74F1779 differs from 74F779 in that it has an additional hold
mode as described in the Function Table.
is High, the data outputs are
is held High. the TC output is not
PIN CONFIGURATION
1I/O1 I/O0
I/O2
2
I/O3
3
GND
4
I/O4
5
I/O5
6
7
I/O6
I/O7
TYPE TYPICAL f
MAX
74F1779 130MHz 100mA
16
CP
15
CET
14
V
13
CC
TC
12
S0
11
S1
10
OE
98
TYPICAL
SUPPLY CURRENT
(TOTAL)
ORDERING INFORMATION
COMMERCIAL RANGE
DESCRIPTION
VCC = 5V ±10%,
T
= 0°C to +70°C
amb
16-pin Plastic DIP N74F1779N SOT38-4
16-pin Plastic SOL N74F1779D SOT162-1
PACKAGE
DRAWING
NUMBER
SF01259
INPUT AND OUTPUT LOADING AND FAN-OUT TABLE
PINS DESCRIPTION
74F(U.L.)
HIGH/LOW
Data inputs 3.5/1.0 70µA/0.6mA
Data outputs 150/40 3.0mA/24mA
S0, S1 Select inputs 1.0/1.0 20µA/0.6mA
OE Output Enable input (active Low) 1.0/1.0 20µA/0.6mA
CET Count Enable Trickle input (active Low) 1.0/1.0 20µA/0.6mA
CP Clock input (active rising edge) 1.0/1.0 20µA/0.6mA
TC Terminal Count output (active Low) 50/33 1.0mA/20mA
NOTE: One (1.0) FAST unit load is defined as: 20µA in the High state and 0.6mA in the Low state.
LOAD VALUE
HIGH/LOW
1989 Apr 06 853–1367 96245
2
Philips Semiconductors Product specification
74F17798-bit bidirectional binary counter (3-State)
LOGIC SYMBOL
14OECET
15
CP
=Pin 13
V
CC
GND=Pin 4
9
I/O0 I/O1 I/O2 I/O3 I/O4 I/O5 I/O6 I/O7
161235678
IEC/IEEE SYMBOL
11
10
14
15
9
0
1
EN4
2 +/C5
1–
EN6
11 10
S0 S1
CTR DIV 256
LOAD
0
DOWN
—
M
3
UP
HOLD
[1]
[2]
[4]
[8]
[16]
[32]
[64]
[128]
4, 5, 8 CT=256
4, 5, 8 CT=0
6
16
1
2
3
5
6
7
8
SF01261
12
SF01260
FUNCTION TABLE
INPUTS
S1 S0 CET OE CP
X X X H X I/O0 to I/O7 in High impedance
12TC
X X X L X Flip-flop outputs appear on I/O lines
L L X H ↑ Parallel load all flip-flops
(not LL) H X ↑ Hold (TC held High)
H H X X ↑ Hold
H L L X ↑ Count up
L H L X ↑ Count down
H = High voltage level
L = Low voltage level
X = Don’t care
↑ = Low-to-High clock transition
(not LL) = S0 and S1 should never be Low voltage level at the
same time in the hold mode only.
1989 Apr 06
3
Philips Semiconductors Product specification
74F17798-bit bidirectional binary counter (3-State)
LOGIC DIAGRAM
11
OE
S0
10
S1
9
16
I/O0
LOAD CONTROL
UP
DOWN
DETAIL A
CP
15
I/O1
I/O2
I/O3
I/O4
I/O5
I/O6
I/O7
1
2
3
5
6
7
8
DETAIL A
DETAIL A
DETAIL A
DETAIL A
DETAIL A
DETAIL A
DETAIL A
=Pin 13
V
CC
GND=Pin 4
1989 Apr 06
CET
14
12
TC
DETAIL A
CP
D
Q
CP
Q
SF01262
TOGGLE
DATA
LOAD
Q
Q
4