LMC555
Application Info
(Continued)
the modulating signal, since the threshold voltage and hence
the time delay is varied.
Figure 11
shows the waveforms
generated for a triangle wave modulation signal.
DS008669-16
DS008669-21
V
CC
= 5V
TIME = 0.1 ms/Div.
R
A
= 3.9 kΩ
R
B
= 3 kΩ
C = 0.01µF
Top Trace: Modulation Input 1V/Div.
Bottom Trace: Output Voltage 2V/Div.
FIGURE 10. Pulse Position Modulator
FIGURE 11. Pulse Position Modulator Waveforms
50% DUTY CYCLE OSCILLATOR
The frequency of oscillation is
f = 1/(1.4 R
C
C)
DS008669-6
FIGURE 12. 50% Duty Cycle Oscillator
7
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