Look-ahead circuitry enhances speed of cascaded counters
Fully synchronous in count modes
Asynchronously presettable with load control
radiation-hardened CMOS
- Latchup immune
High speed
Low power consumption
Single 5 volt supply
Available QML Q or V processes
Flexible package
- 16-pin DIP
- 16-lead flatpack
DESCRIPTION
The UT54ACS190 and the UT54ACTS190 are synchronous 4-
bit reversible up-down BCD decade counters. Synchronous
counting operation is provided by having all flip-flops clocked
simultaneously so that the outputs change coincident with each
other when so instructed. Synchronous operation eliminates the
output counting spikes associated with asynchronous counters.
The outputs of the four flip-flops are triggered on a low-to-high-
level transition of the clock input if the enable input (CTEN) is
low. A logic one applied to CTEN inhibits counting. The di-
rection of the count is determined by the level of the down/up
(D/U) input. When D/U is low, the counter counts up and when
D/U is high, it counts down.
The counters feature a fully independent clock circuit. Changes
at control inputs (CTEN and D/U) that will modify the operating
mode have no effect on the contents of the counter until clocking
occurs.
The counters are fully programmable. The outputs may be pre-
set to either logic level by placing a low on the load input and
entering the desired data at the data inputs. The output will
change to agree with the data inputs independently of the level
of the clock input. The asynchronous load allows counters to
be used as modulo-N dividers by simply modifying the count
length with the preset inputs.
If preset to an illegal state, the counter returns to a normal se-
quence in one or two counts.
PINOUTS
16-Pin DIP
Top View
B
Q
B
Q
A
CTEN
D/U
Q
C
Q
D
V
SS
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
V
DD
A
CLK
RCO
MAX/MIN
LOAD
C
D
16-Lead Flatpack
Top View
B
Q
B
Q
A
CTEN
D/U
Q
C
Q
D
V
SS
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
V
DD
A
CLK
RCO
MAX/MIN
LOAD
C
D
Two outputs have been made available to perform the cascading
function: ripple clock and maximum/minimum (MAX/MIN)
count. The MAX/MIN output produces a high-level output
pulse with a duration approximately equal to one complete cycle
of the clock while the count is zero (all outputs low) counting
down or maximum (9) counting up.
The ripple clock output (RCO) produces a low-level output
pulse under those same conditions but only while the clock input
is low. The counters easily cascade by feeding the RCO to the
enable input of the succeeding counter if parallel clocking is
used, or to the clock input if parallel enabling is used. Use the
MAX/MIN count output to accomplish look-ahead for high-
speed operation.
The devices are characterized over full military temperature
range of -55 C to +125 C.
125
RadHard MSI Logic
UT54ACS190/UT54ACTS190
FUNCTION TABLE
Function
Count up
Count down
Asynchronous
No change
LOAD
H
H
L
CTEN
L
L
X
H
X
D/U
L
H
X
CLK
(11)
LOAD
(15)
(1)
B
C
(9)
5D
(1)
(4)
(8)
7
(2)
(6)
Q
A
Q
Q
Q
D
G4
(13)
RCO
CLK
CTEN
D/U
LOGIC SYMBOL
(4)
CTRDIV 10
G
M2 (DOWN)
(12)
MAX/MIN
Note:
1. Logic symbol in accordance with ANSI/IEEE standard 91-1984 and IEC
Publication 617-12.
LOGIC DIAGRAM
CLK
D/U
(14)
(5)
(13)
RCO
(12)
MAX/MIN
A
(15)
(4)
J
S
Q
(3)
Q
A
CTEN
C
K Q
R
B
(1)
J
S
Q
(2)
Q
B
C
KR Q
C
(10)
J
S
Q
(6)
Q
C
C
K Q
R
D
(9)
S
J
Q
(7)
Q
D
C
K Q
R
LOAD
(11)
RadHard MSI Logic
126
UT54ACS190/UT54ACTS190
RADIATION HARDNESS SPECIFICATIONS
1
PARAMETER
Total Dose
SEU Threshold
2
SEL Threshold
Neutron Fluence
LIMIT
1.0E6
80
120
1.0E14
UNITS
rads(Si)
MeV-cm
2
/mg
MeV-cm
2
/mg
n/cm
2
Notes:
1. Logic will not latchup during radiation exposure within the limits defined in the table.
2. Device storage elements are immune to SEU affects.
ABSOLUTE MAXIMUM RATINGS
SYMBOL
V
DD
V
I/O
T
STG
T
J
T
LS
JC
PARAMETER
Supply voltage
Voltage any pin
Storage Temperature range
Maximum junction temperature
Lead temperature (soldering 5 seconds)
Thermal resistance junction to case
DC input current
Maximum power dissipation
LIMIT
-0.3 to 7.0
-.3 to V
DD
+.3
-65 to +150
+175
+300
20
10
1
UNITS
V
V
C
C
C
C/W
mA
W
I
I
P
D
Note:
1. Stresses outside the listed absolute maximum ratings may cause permanent damage to the device. This is a stress rating only, functional operation of the device
at these or any other conditions beyond limits indicated in the operational sections is not recommended. Exposure to absolute maximum rating conditions for
extended periods may affect device reliability.
RECOMMENDED OPERATING CONDITIONS
SYMBOL
V
DD
V
IN
T
C
PARAMETER
Supply voltage
Input voltage any pin
Temperature range
LIMIT
4.5 to 5.5
0 to V
DD
-55 to + 125
UNITS
V
V
C
127
RadHard MSI Logic
UT54ACS190/UT54ACTS190
DC ELECTRICAL CHARACTERISTICS
7
(V
DD
= 5.0V 10%; V
SS
= 0V
6
, -55 C < T
C
< +125 C)
SYMBOL
V
IL
PARAMETER
Low-level input voltage
1
ACTS
ACS
High-level input voltage
1
ACTS
ACS
Input leakage current
ACTS/ACS
Low-level output voltage
3
ACTS
ACS
High-level output voltage
3
ACTS
ACS
Short-circuit output current
2 ,4
ACTS/ACS
Output current
10
(Sink)
I
OH
Output current
10
(Source)
P
total
I
DDQ
I
DDQ
Power dissipation
2, 8, 9
Quiescent Supply Current
Quiescent Supply Current Delta
ACTS
V
IN
= V
DD
or V
SS
I
OL
= 8.0mA
I
OL
= 100 A
I
OH
= -8.0mA
I
OH
= -100 A
V
O
= V
DD
and V
SS
V
IN
= V
DD
or V
SS
V
OL
= 0.4V
V
IN
= V
DD
or V
SS
V
OH
= V
DD
- 0.4V
C
L
= 50pF
V
DD
= 5.5V
For input under test
V
IN
= V
DD
- 2.1V
For all other inputs
V
IN
= V
DD
or V
SS
V
DD
= 5.5V
C
IN
C
OUT
Input capacitance
5
Output capacitance
5
= 1MHz @ 0V
= 1MHz @ 0V
15
15
pF
pF
2.2
10
1.6
mW/MHz
A
mA
-8
mA
.7V
DD
V
DD
- 0.25
-200
8
200
.5V
DD
.7V
DD
-1
1
CONDITION
MIN
MAX
0.8
.3V
DD
UNIT
V
V
IH
V
I
IN
V
OL
A
0.40
0.25
V
V
OH
V
I
OS
I
OL
mA
mA
RadHard MSI Logic
128
UT54ACS190/UT54ACTS190
Notes:
1. Functional tests are conducted in accordance with MIL-STD-883 with the following input test conditions: V
IH
= V
IH
(min) + 20%, - 0%; V
IL
= V
IL
(max) + 0%,
- 50%, as specified herein, for TTL, CMOS, or Schmitt compatible inputs. Devices may be tested using any input voltage within the above specified range, but
are guaranteed to V
IH
(min) and V
IL
(max).
2. Supplied as a design limit but not guaranteed or tested.
3. Per MIL-PRF-38535, for current density 5.0E5 amps/cm
2
, the maximum product of load capacitance (per output buffer) times frequency should not exceed
3,765 pF/MHz.
4. Not more than one output may be shorted at a time for maximum duration of one second.
5. Capacitance measured for initial qualification and when design changes may affect the value. Capacitance is measured between the designated terminal and V
SS
at frequency of 1MHz and a signal amplitude of 50mV rms maximum.
6. Maximum allowable relative shift equals 50mV.
7. All specifications valid for radiation dose 1E6 rads(Si).
8. Power does not include power contribution of any TTL output sink current.
9. Power dissipation specified per switching output.
10. This value is guaranteed based on characterization data, but not tested.