MC1455, MC1455B,
NCV1455B
Timers
The MC1455 monolithic timing circuit is a highly stable controller
capable of producing accurate time delays or oscillation. Additional
terminals are provided for triggering or resetting if desired. In the time
delay mode, time is precisely controlled by one external resistor and
capacitor. For astable operation as an oscillator, the free−running
frequency and the duty cycle are both accurately controlled with two
external resistors and one capacitor. The circuit may be triggered and
reset on falling waveforms, and the output structure can source or sink
up to 200 mA or drive TTL circuits.
Features
8
1
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MARKING
DIAGRAMS
8
SOIC−8
D SUFFIX
CASE 751
1
8
PDIP−8
P1 SUFFIX
CASE 626
1
x
yyy
A
L
Y, YY
W, WW
G
or G
1
= B or V
= BP1 or P1
= Assembly Location
= Wafer Lot
= Year
= Work Week
= Pb−Free Package
MC1455yyy
AWL
YYWWG
1455x
ALYW
G
•
•
•
•
•
•
•
•
•
Direct Replacement for NE555 Timers
Timing from Microseconds through Hours
Operates in Both Astable and Monostable Modes
Adjustable Duty Cycle
High Current Output Can Source or Sink 200 mA
Output Can Drive TTL
Temperature Stability of 0.005% per
°C
Normally ON or Normally OFF Output
Pb−Free Packages are Available
8
1.0 k
MT2
3
10 k
5
0.01
mF
4
2
8
MC1455
1
6
7
1.0
mF
C
-10 V
t = 1.1; R and C = 22 sec
Time delay (t) is variable by
changing R and C (see Figure 16).
1N4740
3.5 k
250 V
R
20 M
G
MT1
Load
117 Vac/60 Hz
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 9 of this data sheet.
0.1
mF
1N4003
-
10
mF
+
V
R
Reset
5
Control
Voltage
3
7
Output
Discharge
V
O
I
Sink
I
Source
4
8
V
CC
MC1455
Threshold
6
GND
Trigger
1
2
I
th
2.0 k
V
S
7
Discharge
I
CC
700
V
CC
Figure 1. 22 Second Solid State Time Delay Relay Circuit
V
CC
8
6
5
Control Voltage
5k
2
5k
1
GND
4
Reset
+
Comp
-B
5k
+
Comp
A
-
Flip
R Flop
Q
S Inhibit/
Reset
3
Output
+
0.01
mF
Threshold
Trigger
Test circuit for measuring DC parameters (to set output and measure
parameters):
a) When V
S
w
2/3 V
CC
, V
O
is low.
b) When V
S
v
1/3 V
CC
, V
O
is high.
c) When V
O
is low, Pin 7 sinks current. To test for Reset, set V
O
c)
high, apply Reset voltage, and test for current flowing into Pin 7.
c)
When Reset is not in use, it should be tied to V
CC
.
Figure 2. Representative Block Diagram
©
Semiconductor Components Industries, LLC, 2009
Figure 3. General Test Circuit
1
Publication Order Number:
MC1455/D
December, 2009
−
Rev. 10
MC1455, MC1455B, NCV1455B
MAXIMUM RATINGS
(T
A
= +25°C, unless otherwise noted.)
Rating
Power Supply Voltage
Discharge Current (Pin 7)
Power Dissipation (Package Limitation)
P1 Suffix, Plastic Package
Derate above T
A
= +25°C
D Suffix, Plastic Package
Derate above T
A
= +25°C
Operating Temperature Range (Ambient)
MC1455B
MC1455
NCV1455B
Maximum Operating Die Junction Temperature
Storage Temperature Range
Symbol
V
CC
I
7
P
D
P
D
T
A
Value
+18
200
625
5.0
625
160
−40
to +85
0 to +70
−40
to +125
+150
−65
to +150
Unit
Vdc
mA
mW
mW/°C
mW
°C/W
°C
T
J
T
stg
°C
°C
Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the
Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect
device reliability.
ELECTRICAL CHARACTERISTICS
(T
A
= +25°C, V
CC
= +5.0 V to +15 V, unless otherwise noted.)
Characteristics
Operating Supply Voltage Range
Supply Current
V
CC
= 5.0 V, R
L
=
R
V
CC
= 15 V, R
L
=
R,
Low State (Note 1)
Timing Error (R = 1.0 kW to 100 kW) (Note 2)
Initial Accuracy C = 0.1
mF
Drift with Temperature
Drift with Supply Voltage
Threshold Voltage/Supply Voltage
Trigger Voltage
V
CC
= 15 V
V
CC
= 5.0 V
Trigger Current
Reset Voltage
Reset Current
Threshold Current (Note 3)
Discharge Leakage Current (Pin 7)
Control Voltage Level
V
CC
= 15 V
V
CC
= 5.0 V
Output Voltage Low
I
Sink
= 10 mA (V
CC
= 15 V)
I
Sink
= 50 mA (V
CC
= 15 V)
I
Sink
= 100 mA (V
CC
= 15 V)
I
Sink
= 200 mA (V
CC
= 15 V)
I
Sink
= 8.0 mA (V
CC
= 5.0 V)
I
Sink
= 5.0 mA (V
CC
= 5.0 V)
Output Voltage High
V
CC
= 15 V (I
Source
= 200 mA)
V
CC
= 15 V (I
Source
= 100 mA)
V
CC
= 5.0 V (I
Source
= 100 mA)
Rise Time Differential Output
Fall Time Differential Output
1.
2.
3.
4.
V
th
/V
CC
V
T
Symbol
V
CC
I
CC
Min
4.5
−
−
−
−
−
−
−
−
−
0.4
−
−
−
9.0
2.6
−
−
−
−
−
−
−
12.75
2.75
−
−
Typ
−
3.0
10
1.0
50
0.1
2/3
5.0
1.67
0.5
0.7
0.1
0.1
−
10
3.33
0.1
0.4
2.0
2.5
−
0.25
12.5
13.3
3.3
100
100
Max
16
6.0
15
−
−
−
−
−
−
−
1.0
−
0.25
100
11
4.0
0.25
0.75
2.5
−
−
0.35
−
−
−
−
−
V
Unit
V
mA
%
PPM/°C
%/V
I
T
V
R
I
R
I
th
I
dischg
V
CL
mA
V
mA
mA
nA
V
V
OL
V
V
OH
V
t
r
t
f
ns
ns
‘Supply current when output is high is typically 1.0 mA less.
Tested at V
CC
= 5.0 V and V
CC
= 15 V Monostable mode.
This will determine the maximum value of R
A
+ R
B
for 15 V operation. The maximum total R = 20 MW .
T
low
= 0°C for MC1455, T
low
=
−40°C
for MC1455B, NCV1455B
T
high
= +70°C for MC1455, T
high
= +85°C for MC1455B, T
high
= +125°C for NCV1455B
5. NCV prefix is for Automotive and other applications requiring site and change control.
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2
MC1455, MC1455B, NCV1455B
150
ICC , SUPPLY CURRENT (mA)
PW, PULSE WIDTH (ns min)
125
100
75
50
25
0
0
0.1
0.2
0.3
0.4
V
T (min)
, MINIMUM TRIGGER VOLTAGE (x V
CC
= Vdc)
0°C
25°C
70°C
10
25°C
8.0
6.0
4.0
2.0
0
5.0
10
V
CC
, SUPPLY VOLTAGE (Vdc)
15
Figure 4. Trigger Pulse Width
Figure 5. Supply Current
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
1.0
5.0 V
≤
V
CC
≤
15 V
2.0
5.0
10
I
Source
(mA)
20
50
100
25°C
VOL, LOW OUTPUT VOLTAGE (Vdc)
10
VCC -VOH (Vdc)
1.0
25°C
0.1
0.01
1.0
2.0
5.0
10
I
Sink
(mA)
20
50
100
Figure 6. High Output Voltage
Figure 7. Low Output Voltage
@ V
CC
= 5.0 Vdc
10
VOL, LOW OUTPUT VOLTAGE (Vdc)
VOL, LOW OUTPUT VOLTAGE (Vdc)
10
1.0
25°C
1.0
0.1
0.1
25°C
0.01
1.0
2.0
5.0
10
I
Sink
(mA)
20
50
100
0.01
1.0
2.0
5.0
10
I
Sink
(mA)
20
50
100
Figure 8. Low Output Voltage
@ V
CC
= 10 Vdc
Figure 9. Low Output Voltage
@ V
CC
= 15 Vdc
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MC1455, MC1455B, NCV1455B
1.015
t d, DELAY TIME NORMALIZED
1.010
1.005
1.000
0.995
0.990
0.985
0
5.0
10
V
CC
, SUPPLY VOLTAGE (Vdc)
15
20
t d, DELAY TIME NORMALIZED
1.015
1.010
1.005
1.000
0.995
0.990
0.985
- 75
- 50
- 25
0
25
50
75
100
125
T
A
, AMBIENT TEMPERATURE (°C)
Figure 10. Delay Time versus Supply Voltage
Figure 11. Delay Time versus Temperature
300
t pd , PROPAGATION DELAY TIME (ns)
250
200
150
100
70°C
50
0
0
0.1
0.2
0.3
V
T (min)
, MINIMUM TRIGGER VOLTAGE (x V
CC
= Vdc)
0.4
25°C
0°C
Figure 12. Propagation Delay
versus Trigger Voltage
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4
MC1455, MC1455B, NCV1455B
Control Voltage
Threshold
Comparator
V
CC
4.7 k
830
4.7 k
1.0 k
6.8 k
Trigger
Comparator
Flip-Flop
Output
5.0 k
Threshold
7.0 k
3.9 k
10 k
cb
5.0 k
e
4.7 k
c
b
Output
Trigger
Reset
Reset
Discharge
GND
Discharge
100
100 k
5.0 k
220
4.7 k
Figure 13. Representative Circuit Schematic
GENERAL OPERATION
The MC1455 is a monolithic timing circuit which uses an
external resistor
−
capacitor network as its timing element. It
can be used in both the monostable (one−shot) and astable
modes with frequency and duty cycle controlled by the
capacitor and resistor values. While the timing is dependent
upon the external passive components, the monolithic circuit
provides the starting circuit, voltage comparison and other
functions needed for a complete timing circuit. Internal to the
integrated circuit are two comparators, one for the input
signal and the other for capacitor voltage; also a flip−flop and
digital output are included. The comparator reference
voltages are always a fixed ratio of the supply voltage thus
providing output timing independent of supply voltage.
Monostable Mode
has been triggered by an input signal, it cannot be retriggered
until the present timing period has been completed. The time
that the output is high is given by the equation t = 1.1 R
A
C.
Various combinations of R and C and their associated times
are shown in Figure 16. The trigger pulse width must be less
than the timing period.
A reset pin is provided to discharge the capacitor, thus
interrupting the timing cycle. As long as the reset pin is low,
the capacitor discharge transistor is turned “on” and prevents
the capacitor from charging. While the reset voltage is applied
the digital output will remain the same. The reset pin should
be tied to the supply voltage when not in use.
+V
CC
(5.0 V to 15 V)
In the monostable mode, a capacitor and a single resistor
are used for the timing network. Both the threshold terminal
and the discharge transistor terminal are connected together
in this mode (refer to circuit in Figure 14). When the input
voltage to the trigger comparator falls below 1/3 V
CC
, the
comparator output triggers the flip−flop so that its output sets
low. This turns the capacitor discharge transistor “off” and
drives the digital output to the high state. This condition
allows the capacitor to charge at an exponential rate which is
set by the RC time constant. When the capacitor voltage
reaches 2/3 V
CC
, the threshold comparator resets the
flip−flop. This action discharges the timing capacitor and
returns the digital output to the low state. Once the flip−flop
R
L
Output
3
R
L
2
Trigger
Reset
4
V
CC
8
R
A
Discharge
7
6
Threshold
5
C
MC1455
1
Control
Voltage
0.01
mF
Figure 14. Monostable Circuit
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5
Embedded System
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