SA555 Fairchild Semiconductor, SA555 Datasheet - Page 9
SA555
Manufacturer Part Number
SA555
Description
Timers & Support Products
Manufacturer
Fairchild Semiconductor
Type
Standardr
Datasheet
1.SA555.pdf
(14 pages)
Specifications of SA555
Number Of Internal Timers
1
Supply Voltage (max)
16 V
Supply Voltage (min)
4.5 V
Maximum Power Dissipation
600 mW
Maximum Operating Temperature
+ 85 C
Minimum Operating Temperature
- 40 C
Mounting Style
Through Hole
Package / Case
PDIP-8
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
SA555D
Manufacturer:
S
Quantity:
20 000
Company:
Part Number:
SA555DR
Manufacturer:
Texas Instruments
Quantity:
20 000
Part Number:
SA555DR
Manufacturer:
TI/德州仪器
Quantity:
20 000
Company:
Part Number:
SA555DRG4
Manufacturer:
NEC
Quantity:
6 218
Company:
Part Number:
SA555DT
Manufacturer:
STMicroelectronics
Quantity:
68 143
Part Number:
SA555DT
Manufacturer:
ST
Quantity:
20 000
Part Number:
SA555N
Manufacturer:
S
Quantity:
20 000
6. Linear Ramp
6. Linear Ramp
When the pull-up resistor RA in the monostable circuit shown in Figure 1 is replaced with constant current source, the V
increases linearly, generating a linear ramp. Figure 13 shows the linear ramp generating circuit and Figure 14 illustrates the
generated linear ramp waveforms.
In Figure 13, current source is created by PNP transistor Q1 and resistor R1, R2, and R
For example, if Vcc=15V, R
V
Ic=(15-10.7)/20k=0.215mA
6. Linear Ramp
6. Linear Ramp
Figure 11. Circuit for Pulse Position Modulation
Figure 11. Circuit for Pulse Position Modulation
Figure 11. Circuit for Pulse Position Modulation
Figure 11. Circuit for Pulse Position Modulation
E
=0.7V+10V=10.7V
Output
Output
Output
Output
Output
V
Figure 13. Circuit for Linear Ramp
Figure 13. Circuit for Linear Ramp
Figure 13. Circuit for Linear Ramp
Figure 13. Circuit for Linear Ramp
E
=
I
C
V
3
2
2
3
BE
=
TRIG
OUT
OUT
TRIG
V
-------------------------- -
RESET
RESET
+
Here, V
4
CC
--------------------- - V
R 1
4
R
GND
R 2
E
–
+
1
GND
V
R 2
1
E
E is
Vcc
THRES
DISCH
8
CONT
E
CC
=20k , R1=5kW, R2=10k , and V
THRES
Vcc
DISCH
CONT
8
7
6
5
12
Modulation
Modulation
Modulation
Modulation
6
7
5
13
C C C C
C2
R R R R
R R R R
A A A A
B B B B
+Vcc
+Vcc
+Vcc
+Vcc
R
C1
E
Q1
+Vcc
R2
R1
Figure 12. Waveforms of pulse position modulation
Figure 12. Waveforms of pulse position modulation
Figure 12. Waveforms of pulse position modulation
Figure 12. Waveforms of pulse position modulation
BE
Figure 14. Waveforms of Linear Ramp
Figure 14. Waveforms of Linear Ramp
Figure 14. Waveforms of Linear Ramp
Figure 14. Waveforms of Linear Ramp
=0.7V,
E
.
LM555/NE555/SA555
C1
9 9 9 9