Data Sheet
Table Of Contents
- 1 Schematic diagrams
- 2 Absolute maximum ratings and operating conditions
- 3 Electrical characteristics
- Table 3. Tamb = +25˚ C, VCC = +5 V to +15 V (unless otherwise specified)
- Figure 3. Minimum pulse width required for triggering
- Figure 4. Supply current versus supply voltage
- Figure 5. Delay time versus temperature
- Figure 6. Low output voltage versus output sink current
- Figure 7. Low output voltage versus output sink current
- Figure 8. Low output voltage versus output sink current
- Figure 9. High output voltage drop versus output
- Figure 10. Delay time versus supply voltage
- Figure 11. Propagation delay versus voltage level of trigger value
- 4 Application information
- 5 Package information
- 6 Ordering information
- 7 Revision history
Application information NE555 - SA555 - SE555
12/20 Doc ID 2182 Rev 6
4.3 Pulse width modulator
When the timer is connected in the monostable mode and triggered with a continuous pulse
train, the output pulse width can be modulated by a signal applied to pin 5. Figure 18 shows
the circuit.
Figure 18. Pulse width modulator
4.4 Linear ramp
When the pull-up resistor, R
A
, in the monostable circuit is replaced by a constant current
source, a linear ramp is generated. Figure 19 shows a circuit configuration that will perform
this function.
Figure 19. Linear ramp
Trigger
Output
R
C
NE555
2
4
3
1
5
6
7
Modulation
Input
8
A
V
CC
Trigger
Output
C
NE555
2
4
3
1
5
6
7
8
E
V
CC
0.01
μ
F
R2
R1
R
2N4250
or equiv.