MC1455 ON Semiconductor, MC1455 Datasheet - Page 7

• Manufacturer Part Number: MC1455
• Description: Timing Circuit
• Manufacturer: ON Semiconductor

Linear Voltage Ramp
constant current source to provide a linear ramp voltage. The
capacitor still charges from 0 V
ramp time is given by:
If V
independent of V
In the monostable mode, the resistor can be replaced by a
Trigger
Output
Digital
B
t =
is much larger than V
(R
Figure 22. Linear Voltage Ramp Waveforms
3
2
E
Figure 20. Linear Voltage Sweep Circuit
= 10 kW, R2 = 100 kW, R1 = 39 kW, C = 0.01 mF, V
Reset
2
3
V
CC
1
CC
MC1455
4
.
, where I =
1
8
V
V
t = 100 ms/cm
CC
CC
0.01 mF
7
6
5
CC
BE
Sweep
Output
V
, then t can be made
to 2/3 V
Control
Voltage
CC
V
R
E
E
I
− V
MC1455, MC1455B, NCV1455B
R
C
B
E
2N4403
or Equiv
APPLICATIONS INFORMATION
CC
− V
. The linear
BE
CC
= 15 V)
http://onsemi.com
R1
V
R2
B
7
Missing Pulse Detector
pulse fails to occur within the delay of the timer. To
accomplish this, set the time delay to be slightly longer than
the time between successive input pulses. The timing cycle
is then continuously reset by the input pulse train until a
change in frequency or a missing pulse allows completion of
the timing cycle, causing a change in the output level.
The timer can be used to produce an output when an input
Output
Input
Figure 23. Missing Pulse Detector Waveforms
R
L
Figure 21. Missing Pulse Detector
Trigger
(R
A
+V
3
2
= 2.0 kW, R
CC
Reset
(5.0 V to 15 V)
4
MC1455
L
= 1.0 kW, C = 0.01 mF, V
1
t = 500 ms/cm
8
V
CC
Discharge
Threshold
6
5
0.01 mF
7
Control
Voltage
CC
= 15 V)
R
A
2N4403
or Equiv
C