LMC555CBP/NOPB National Semiconductor, LMC555CBP/NOPB Datasheet - Page 7

• Manufacturer Part Number: LMC555CBP/NOPB
• Manufacturer: National Semiconductor
• Type: Standardr

Specifications of LMC555CBP/NOPB

• # Internal Timers: 1
• Power Dissipation: 568mW
• Propagation Delay Time: 100ns
• Operating Supply Voltage (typ): 1.5V
• Package Type: uSMD
• High Level Output Current: -10mA
• Low Level Output Current: 50mA
• Pin Count: 8
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Lead Free Status / Rohs Status: Compliant

V
TIME = 0.2 ms/Div. Bottom Trace: Output Voltage 2 V/Div.
R
C = 0.01 µF
PULSE POSITION MODULATOR
This application uses the timer connected for astable opera-
tion, as in
to the control voltage terminal. The pulse position varies with
the modulating signal, since the threshold voltage and hence
the time delay is varied.
erated for a triangle wave modulation signal.
CC
A
= 9.1 kΩ
= 5V
FIGURE 9. Pulse Width Modulator Waveforms
FIGURE 10. Pulse Position Modulator
Figure
10, with a modulating signal again applied
Top Trace: Modulation 1 V/Div.
Figure 11
shows the waveforms gen-
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V
TIME = 0.1 ms/Div.
R
R
C = 0.01 µF
50% DUTY CYCLE OSCILLATOR
The frequency of oscillation is
CC
A
B
= 3.9 kΩ
= 3 kΩ
= 5V
FIGURE 11. Pulse Position Modulator Waveforms
f = 1/(1.4 R
FIGURE 12. 50% Duty Cycle Oscillator
micro SMD Marking Orientation
C
C)
Bottom Trace: Output Voltage 2 V/Div.
Top Trace: Modulation Input 1 V/Div.
Top View
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