lm555jan National Semiconductor Corporation, lm555jan Datasheet - Page 10

• Manufacturer Part Number: lm555jan
• Description: Timer
• Manufacturer: National Semiconductor Corporation

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the time delay is varied.
erated for a triangle wave modulation signal.
V
TIME = 0.1 ms/DIV.
R
R
C = 0.01μF
LINEAR RAMP
When the pull-up resistor, R
placed by a constant current source, a linear ramp is gener-
ated.
this function.
CC
A
B
= 3.9kΩ
= 3kΩ
= 5V
Figure 12
FIGURE 10. Pulse Position Modulator
FIGURE 11. Pulse Position Modulator
shows a circuit configuration that will perform
Top Trace: Modulation Input 1V/Div.
Bottom Trace: Output 2V/Div.
Figure 11
A
, in the monostable circuit is re-
shows the waveforms gen-
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10
Figure 13
The time interval is given by:
V
TIME = 20μs/DIV. Middle Trace: Output 5V/Div.
R
R
R
C = 0.01 μF
50% DUTY CYCLE OSCILLATOR
For a 50% duty cycle, the resistors R
nected as in
the same as previous, t
is t
Thus the frequency of oscillation is
CC
1
2
E
= 47kΩ
= 100kΩ
= 2.7 kΩ
2
= 5V
=
shows waveforms generated by the linear ramp.
Figure
Bottom Trace: Capacitor Voltage 1V/Div.
Top Trace: Input 3V/Div.
FIGURE 13. Linear Ramp
14. The time period for the output high is
1
FIGURE 12.
V
= 0.693 R
BE
0.6V
A
C. For the output low it
A
and R
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B
may be con-
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