LMC555CN National Semiconductor, LMC555CN Datasheet - Page 7

• Manufacturer Part Number: LMC555CN
• Description: IC, TIMER CMOS, DIP8, 555
• Manufacturer: National Semiconductor

Specifications of LMC555CN

• Operating Mode: Astable / Monostable
• No. Of Timers: 1
• Clock External Input: No
• Supply Voltage Range: 1.5V To 12V
• Digital Ic Case Style: DIP
• No. Of Pins: 8
• Operating Temperature Range: -40°C
• Frequency: 3MHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Application Info
PULSE POSITION MODULATOR
This application uses the timer connected for astable opera-
tion, as in Figure 10, with a modulating signal again applied
to the control voltage terminal. The pulse position varies with
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.
V
TIME = 0.1 ms/Div.
R
R
C = 0.01µF
CC
A
B
= 3.9 kΩ
= 3 kΩ
FIGURE 11. Pulse Position Modulator Waveforms
= 5V
FIGURE 10. Pulse Position Modulator
Bottom Trace: Output Voltage 2V/Div.
Top Trace: Modulation Input 1V/Div.
(Continued)
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50% DUTY CYCLE OSCILLATOR
The frequency of oscillation is
Bumps are numbered counter-clockwise
f = 1/(1.4 R
FIGURE 12. 50% Duty Cycle Oscillator
micro SMD Marking Orientation
C
C)
Top View
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