  
 
SLFS022E − SEPTEMBER 1973 − REVISED MARCH 2004
1
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
DTiming From Microseconds to Hours
DAstable or Monostable Operation
DAdjustable Duty Cycle
DTTL-Compatible Output Can Sink or Source
Up To 200 mA
description/ordering information
These devices are precision timing circuits
capable of producing accurate time delays or
oscillation. In the time-delay or monostable mode
of operation, the timed interval is controlled by a
single external resistor and capacitor network. In
the astable mode of operation, the frequency and
duty cycle can be controlled independently with
two external resistors and a single external
capacitor.
The threshold and trigger levels normally are
two-thirds and one-third, respectively, of VCC.
These levels can be altered by use of the
control-voltage terminal. When the trigger input
falls below the trigger level, the flip-flop is set and
the output goes high. If the trigger input is above
the trigger level and the threshold input is above
the threshold level, the flip-flop is reset and
the output is low. The reset (RESET) input can override all other inputs and can be used to initiate a new timing
cycle. When RESET goes low, the flip-flop is reset and the output goes low. When the output is low, a
low-impedance path is provided between discharge (DISCH) and ground.
The output circuit is capable of sinking or sourcing current up to 200 mA. Operation is specified for supplies of
5 V to 15 V. With a 5-V supply, output levels are compatible with TTL inputs.
Copyright 2004, Texas Instruments Incorporated
        !
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 $%!  &   % 
&   !
1
2
3
4
8
7
6
5
GND
TRIG
OUT
RESET
VCC
DISCH
THRES
CONT
NE555 ...D, P, PS, OR PW PACKAGE
SA555 ...D OR P PACKAGE
SE555 . . . D, JG, OR P PACKAGE
(TOP VIEW)
32120 19
910111213
4
5
6
7
8
18
17
16
15
14
NC
DISCH
NC
THRES
NC
NC
TRIG
NC
OUT
NC
SE555 . . . FK PACKAGE
(TOP VIEW)
NC
GND
NC
CONT
NC VCC
NC
NC
RESET
NC
NC − No internal connection
    '()(*+*    
 "$ !   "  
&   %  &   !
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
  
 
SLFS022E − SEPTEMBER 1973 − REVISED MARCH 2004
2POST OFFICE BOX 655303 DALLAS, TEXAS 75265
description/ordering information (continued)
ORDERING INFORMATION
TAVTHRES
MAX
VCC = 15 V PACKAGEORDERABLE
PART NUMBER TOP-SIDE
MARKING
PDIP (P) Tube of 50 NE555P NE555P
SOIC (D)
Tube of 75 NE555D
NE555
0°C to 70°C
11.2 V
SOIC (D) Reel of 2500 NE555DR NE555
0°C to 70°C11.2 V SOP (PS) Reel of 2000 NE555PSR N555
TSSOP (PW)
Tube of 150 NE555PW
N555
TSSOP (PW) Reel of 2000 NE555PWR N555
PDIP (P) Tube of 50 SA555P SA555P
−40°C to 85°C11.2 V
SOIC (D)
Tube of 75 SA555D
SA555
−40 C to 85 C
11.2 V
SOIC (D) Reel of 2000 SA555DR SA555
PDIP (P) Tube of 50 SE555P SE555P
SOIC (D)
Tube of 75 SE555D
SE555D
−55°C to 125°C10.6 V SOIC (D) Reel of 2500 SE555DR SE555D
−55 C to 125 C
10.6 V
CDIP (JG) Tube of 50 SE555JG SE555JG
LCCC (FK) Tube of55 SE555FK SE555FK
Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
FUNCTION TABLE
RESET TRIGGER
VOLTAGETHRESHOLD
VOLTAGEOUTPUT DISCHARGE
SWITCH
Low Irrelevant Irrelevant Low On
High <1/3 VDD Irrelevant High Off
High >1/3 VDD >2/3 VDD Low On
High >1/3 VDD <2/3 VDD As previously established
Voltage levels shown are nominal.
  
 
SLFS022E − SEPTEMBER 1973 − REVISED MARCH 2004
3
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
functional block diagram
1
S
R
R1
TRIG
THRES
VCC CONT
RESET
OUT
DISCH
GND
ÎÎ
Î
Î
Î
Î
Î
Î
Î
Pin numbers shown are for the D, JG, P, PS, and PW packages.
NOTE A: RESET can override TRIG, which can override THRES.
4
8
5
6
2
1
7
3
  
 
SLFS022E − SEPTEMBER 1973 − REVISED MARCH 2004
4POST OFFICE BOX 655303 DALLAS, TEXAS 75265
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage, VCC (see Note 1) 18 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input voltage (CONT, RESET, THRES, and TRIG) VCC
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Output current ±225 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Package thermal impedance, θJA (see Notes 2 and 3): D package 97°C/W. . . . . . . . . . . . . . . . . . . . . . . . . . . .
P package 85°C/W. . . . . . . . . . . . . . . . . . . . . . . . . . . .
PS package 95°C/W. . . . . . . . . . . . . . . . . . . . . . . . . . .
PW package 149°C/W. . . . . . . . . . . . . . . . . . . . . . . . .
Package thermal impedance, θJC (see Notes 4 and 5): FK package 5.61°C/W. . . . . . . . . . . . . . . . . . . . . . . . .
JG package 14.5°C/W. . . . . . . . . . . . . . . . . . . . . . . . .
Operating virtual junction temperature, TJ 150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Case temperature for 60 seconds: FK package 260°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lead temperature 1,6 mm (1/16 inch) from case for 60 seconds: JG package 300°C. . . . . . . . . . . . . . . . . . .
Storage temperature range, Tstg −65°C to 150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTES: 1. All voltage values are with respect to GND.
2. Maximum power dissipation is a function of TJ(max), θJA, and TA. The maximum allowable power dissipation at any allowable
ambient temperature is PD = (TJ(max) − TA)/θJA. Operating at the absolute maximum TJ of 150°C can affect reliability.
3. The package thermal impedance is calculated in accordance with JESD 51-7.
4. Maximum power dissipation is a function of TJ(max), θJC, and TC. The maximum allowable power dissipation at any allowable case
temperature is PD = (TJ(max) − TC)/θJC. Operating at the absolute maximum TJ of 150°C can affect reliability.
5. The package thermal impedance is calculated in accordance with MIL-STD-883.
recommended operating conditions
MIN MAX UNIT
VCC
Supply voltage
SA555, NE555 4.5 16
V
VCC Supply voltage SE555 4.5 18 V
VIInput voltage (CONT, RESET, THRES, and TRIG) VCC V
IOOutput current ±200 mA
NE555 0 70
T
A
Operating free-air temperature SA555 −40 85 °C
TA
Operating free-air temperature
SE555 −55 125
C
  
 
SLFS022E − SEPTEMBER 1973 − REVISED MARCH 2004
5
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
electrical characteristics, VCC = 5 V to 15 V, TA = 25°C (unless otherwise noted)
TEST CONDITIONS
SE555 NE555
SA555
UNIT
TEST CONDITIONS
MIN TYP MAX MIN TYP MAX
UNIT
VCC = 15 V 9.4 10 10.6 8.8 10 11.2
V
THRES voltage level VCC = 5 V 2.7 3.3 4 2.4 3.3 4.2 V
THRES current (see Note 6) 30 250 30 250 nA
VCC = 15 V
4.8 5 5.2 4.5 5 5.6
VCC = 15 V TA = −55°C to 125°C 3 6
V
TRIG voltage level
VCC = 5 V
1.45 1.67 1.9 1.1 1.67 2.2 V
VCC = 5 V TA = −55°C to 125°C 1.9
TRIG current TRIG at 0 V 0.5 0.9 0.5 2 µA
0.3 0.7 1 0.3 0.7 1
V
RESET voltage level TA = −55°C to 125°C 1.1 V
RESET at VCC 0.1 0.4 0.1 0.4
mA
RESET current RESET at 0 V −0.4 −1 −0.4 −1.5 mA
DISCH switch off-state current 20 100 20 100 nA
VCC = 15 V
9.6 10 10.4 9 10 11
VCC = 15 V TA = −55°C to 125°C 9.6 10.4
V
CONT voltage (open circuit)
VCC = 5 V
2.9 3.3 3.8 2.6 3.3 4 V
VCC = 5 V TA = −55°C to 125°C 2.9 3.8
VCC = 15 V,
0.1 0.15 0.1 0.25
VCC = 15 V,
IOL = 10 mA TA = −55°C to 125°C 0.2
VCC = 15 V,
0.4 0.5 0.4 0.75
VCC = 15 V,
IOL = 50 mA TA = −55°C to 125°C 1
VCC = 15 V,
2 2.2 2 2.5
VCC = 15 V,
IOL = 100 mA TA = −55°C to 125°C 2.7
V
VCC = 15 V, IOL = 200 mA 2.5 2.5
V
VCC = 5 V,
IOL = 3.5 mA TA = −55°C to 125°C 0.35
VCC = 5 V,
0.1 0.2 0.1 0.35
VCC = 5 V,
IOL = 5 mA TA = −55°C to 125°C 0.8
VCC = 5 V, IOL = 8 mA 0.15 0.25 0.15 0.4
VCC = 15 V,
13 13.3 12.75 13.3
VCC = 15 V,
IOH = −100 mA TA = −55°C to 125°C 12
High-level output voltage VCC = 15 V, IOH = −200 mA 12.5 12.5 V
VCC = 5 V,
3 3.3 2.75 3.3
V
VCC = 5 V,
IOH = −100 mA TA = −55°C to 125°C 2
Output low,
VCC = 15 V 10 12 10 15
Output low,
No load VCC = 5 V 3 5 3 6
mA
Output high,
VCC = 15 V 9 10 9 13
mA
Output high,
No load VCC = 5 V 2 4 2 5
NOTE 6: This parameter influences the maximum value of the timing resistors RA and RB in the circuit of Figure 12. For example, when
VCC = 5 V, the maximum value is R = RA + RB 3.4 M, and for VCC = 15 V, the maximum value is 10 MΩ.
  
 
SLFS022E − SEPTEMBER 1973 − REVISED MARCH 2004
6POST OFFICE BOX 655303 DALLAS, TEXAS 75265
operating characteristics, VCC = 5 V and 15 V
PARAMETER
TEST
CONDITIONS
SE555 NE555
SA555
UNIT
PARAMETER
CONDITIONS
MIN TYP MAX MIN TYP MAX
UNIT
Initial error
Each timer, monostable§
TA = 25°C
0.5 1.5* 1 3
%
Initial error
of timing intervalEach timer, astableTA = 25°C1.5 2.25 %
Temperature coefficient
Each timer, monostable§
TA = MIN to MAX
30 100* 50
ppm/°C
Temperature coefficient
of timing interval Each timer, astableTA = MIN to MAX 90 150 ppm/°C
Supply-voltage sensitivity
Each timer, monostable§
TA = 25°C
0.05 0.2* 0.1 0.5
%/V
Supply-voltage sensitivity
of timing interval Each timer, astableTA = 25°C0.15 0.3 %/V
Output-pulse rise time CL = 15 pF,
TA = 25°C100 200* 100 300 ns
Output-pulse fall time CL = 15 pF,
TA = 25°C100 200* 100 300 ns
* On products compliant to MIL-PRF-38535, this parameter is not production tested.
For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
Timing interval error is defined as the difference between the measured value and the average value of a random sample from each process
run.
§Values specified are for a device in a monostable circuit similar to Figure 9, with the following component values: RA = 2 kto 100 k,
C = 0.1 µF.
Values specified are for a device in an astable circuit similar to Figure 12, with the following component values: RA = 1 k to 100 k,
C = 0.1 µF.
  
 
SLFS022E − SEPTEMBER 1973 − REVISED MARCH 2004
7
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
TYPICAL CHARACTERISTICS
Figure 1
ÏÏÏÏ
TA = 125°C
ÏÏÏ
TA = 25°C
IOL − Low-Level Output Current − mA
ÏÏÏÏ
VCC = 5 V
LOW-LEVEL OUTPUT VOLTAGE
vs
LOW-LEVEL OUTPUT CURRENT
ÏÏÏÏÏ
ÏÏÏÏÏ
TA = −55°C
0.1
0.04
0.01 1 2 4 7 10 20 40 70 100
0.07
1
0.4
0.7
10
4
7
0.02
0.2
2
− Low-Level Output Voltage − VVOL
Figure 2
ÏÏÏÏÏ
ÏÏÏÏÏ
VCC = 10 V
LOW-LEVEL OUTPUT VOLTAGE
vs
LOW-LEVEL OUTPUT CURRENT
− Low-Level Output Voltage − VVOL
IOL − Low-Level Output Current − mA
0.1
0.04
0.01 1 2 4 7 10 20 40 70 100
0.07
1
0.4
0.7
10
4
7
0.02
0.2
2
ÏÏÏÏ
ÏÏÏÏ
TA = 125°C
ÏÏÏÏ
ÏÏÏÏ
TA = 25°C
ÏÏÏÏ
ÏÏÏÏ
TA= −55°C
Figure 3
TA = 125°C
TA = 25°C
TA = −55°C
ÏÏÏÏÏ
ÏÏÏÏÏ
VCC = 15 V
LOW-LEVEL OUTPUT VOLTAGE
vs
LOW-LEVEL OUTPUT CURRENT
− Low-Level Output Voltage − VVOL
IOL − Low-Level Output Current − mA
0.1
0.04
0.01 1 2 4 7 10 20 40 70 100
0.07
1
0.4
0.7
10
4
7
0.02
0.2
2
Figure 4
1
0.6
0.2
0
1.4
1.8
2.0
0.4
1.6
0.8
1.2
IOH − High-Level Output Current − mA
ÏÏÏÏ
TA = 125°C
ÏÏÏÏ
ÏÏÏÏ
TA = 25°C
10
0
704020107421
ÏÏÏÏÏÏ
ÏÏÏÏÏÏ
VCC = 5 V to 15 V
ÏÏÏÏ
TA = −55°C
DROP BETWEEN SUPPLY VOLTAGE AND OUTPUT
vs
HIGH-LEVEL OUTPUT CURRENT
VCC VOH − Voltage Drop − V
)
(
Data for temperatures below 0°C and above 70°C are applicable for SE555 circuits only.
  
 
SLFS022E − SEPTEMBER 1973 − REVISED MARCH 2004
8POST OFFICE BOX 655303 DALLAS, TEXAS 75265
TYPICAL CHARACTERISTICS
Figure 5
5
4
2
1
0
9
3
567891011
− Supply Current − mA
7
6
8
SUPPLY CURRENT
vs
SUPPLY VOLTAGE
10
12 13 14 15
TA = 25°C
TA = 125°C
TA = −55°C
Output Low,
No Load
CC
I
VCC − Supply Voltage − V
Figure 6
1
0.995
0.990
0.9850510
1.005
1.010
NORMALIZED OUTPUT PULSE DURATION
(MONOSTABLE OPERATION)
vs
SUPPLY VOLTAGE
1.015
15 20
CC
VPulse Duration Relative to Value at = 10 V
VCC − Supply Voltage − V
Figure 7
1
0.995
0.990
0.985
−75 −25 25
1.005
1.010
NORMALIZED OUTPUT PULSE DURATION
(MONOSTABLE OPERATION)
vs
FREE-AIR TEMPERATURE
1.015
75 125
Pulse Duration Relative to Value at = 25
TA − Free-Air Temperature − °C
−50 0 50 100
VCC = 10 V
TAC
°
Figure 8
150
100
50
0
200
250
300
− Propagation Delay Time − ns
PROPAGATION DELAY TIME
vs
LOWEST VOLTAGE LEVEL
OF TRIGGER PULSE
Lowest Voltage Level of Trigger Pulse
TA = −55°C
TA = 125°C
TA = 25°C
tPD
TA = 0°C
TA = 70°C
0 0.1 x VCC 0.2 x VCC 0.3 x VCC 0.4 x VC
C
Data for temperatures below 0°C and above 70°C are applicable for SE555 series circuits only.
  
 
SLFS022E − SEPTEMBER 1973 − REVISED MARCH 2004
9
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
APPLICATION INFORMATION
monostable operation
For monostable operation, any of these timers can be connected as shown in Figure 9. If the output is low,
application o f a negative-going pulse to the trigger (TRIG) sets the flip-flop (Q goes low), drives the output high,
and turns off Q1. Capacitor C then is charged through RA until the voltage across the capacitor reaches the
threshold voltage of the threshold (THRES) input. If TRIG has returned to a high level, the output of the threshold
comparator resets the flip-flop (Q goes high), drives the output low, and discharges C through Q1.
VCC
(5 V to 15 V)
RARL
Output
GND
OUT
VCC
CONT
RESET
DISCH
THRES
TRIGInput
ÎÎ
58
4
7
6
2
3
1
Pin numbers shown are for the D, JG, P, PS, and PW packages.
Figure 9. Circuit for Monostable Operation
Voltage − 2 V/div
Time − 0.1 ms/div
ÏÏÏÏÏÏ
Capacitor Voltage
Output Voltage
Input Voltage
ÏÏÏÏÏ
ÏÏÏÏÏ
ÏÏÏÏÏ
ÏÏÏÏÏ
RA = 9.1 k
CL = 0.01 µF
RL = 1 k
See Figure 9
Figure 10. Typical Monostable Waveforms
Monostable operation is initiated when TRIG
voltage falls below the trigger threshold. Once
initiated, the sequence ends only if TRIG is high
at the end of the timing interval. Because of the
threshold level and saturation voltage of Q1,
the output pulse duration is approximately
tw = 1.1RAC. Figure 11 is a plot of the time
constant for various values of RA and C. The
threshold levels and charge rates both are directly
proportional t o the supply voltage, VCC. The timing
interval is, therefore, independent of the supply
voltage, so long as the supply voltage is constant
during the time interval.
Applying a negative-going trigger pulse
simultaneously to RESET and TRIG during the
timing interval discharges C and reinitiates the
cycle, commencing on the positive edge of the
reset pulse. The output is held low as long as the
reset pulse is low. To prevent false triggering,
when RESET is not used, it should be connected
to VCC.
− Output Pulse Duration − s
C − Capacitance − µF
10
1
10−1
10−2
10−3
10−4
10
0
1010.10.01
10−5
0.001
tw
RA = 10 M
RA = 10 k
RA = 1 k
RA = 100 k
RA = 1 M
Figure 11. Output Pulse Duration vs Capacitance
  
 
SLFS022E − SEPTEMBER 1973 − REVISED MARCH 2004
10 POST OFFICE BOX 655303 DALLAS, TEXAS 75265
APPLICATION INFORMATION
astable operation
As shown in Figure 12, adding a second resistor, RB, to the circuit of Figure 9 and connecting the trigger input
to the threshold input causes the timer to self-trigger and run as a multivibrator. The capacitor C charges through
RA and RB and then discharges through RB only. Therefore, the duty cycle is controlled by the values of RA and
RB.
This astable connection results in capacitor C charging and discharging between the threshold-voltage level
(0.67 ×VCC) and the trigger-voltage level (0.33 ×VCC). As in the monostable circuit, charge and discharge
times (and, therefore, the frequency and duty cycle) are independent of the supply voltage.
GND
OUT
VCC
CONT
RESET
DISCH
THRES
TRIG
C
RB
RA
Output
RL
0.01 µF
V
CC
(5 V to 15 V)
(see Note A)
Î
NOTE A: Decoupling CONT voltage to ground with a capacitor can
improve operation. This should be evaluated for individua
l
applications.
Open
58
4
7
6
2
3
1
Pin numbers shown are for the D, JG, P, PS, and PW packages.
Figure 12. Circuit for Astable Operation
Voltage − 1 V/div
Time − 0.5 ms/div
tH
Capacitor Voltage
Output Voltage
tL
ÏÏÏÏÏÏÏÏÏ
ÏÏÏÏÏÏÏÏÏ
ÏÏÏÏÏÏÏÏÏ
RA = 5 kW RL = 1 kW
RB = 3 kW See Figure 12
C = 0.15 µF
Figure 13. Typical Astable Waveforms
  
 
SLFS022E − SEPTEMBER 1973 − REVISED MARCH 2004
11
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
APPLICATION INFORMATION
astable operation (continued)
Figure 13 shows typical waveforms generated during astable operation. The output high-level duration tH and
low-level duration tL can be calculated as follows:
tH+0.693 (RA)RB) C
tL+0.693 (RB) C
Other useful relationships are shown below.
period +tH)tL+0.693 (RA)2RB)C
frequency [1.44
(RA)2RB)C
Output driver duty cycle +tL
tH)tL+RB
RA)2RB
Output waveform duty cycle
+tL
tH+RB
RA)RB
Low-to-high ratio
+tH
tH)tL+1– RB
RA)2RB
f − Free-Running Frequency − Hz
C − Capacitance − µF
100 k
10 k
1 k
100
10
1
10
0
1010.10.01
0.1
0.001
RA + 2 RB = 10 M
RA + 2 RB = 1 M
RA + 2 RB = 100 k
RA + 2 RB = 10 k
RA + 2 RB = 1 k
Figure 14. Free-Running Frequency
  
 
SLFS022E − SEPTEMBER 1973 − REVISED MARCH 2004
12 POST OFFICE BOX 655303 DALLAS, TEXAS 75265
APPLICATION INFORMATION
missing-pulse detector
The circuit shown in Figure 15 can be used to detect a missing pulse or abnormally long spacing between
consecutive pulses in a train of pulses. The timing interval of the monostable circuit is retriggered continuously
by the input pulse train as long as the pulse spacing is less than the timing interval. A longer pulse spacing,
missing pulse, or terminated pulse train permits the timing interval to be completed, thereby generating an
output pulse as shown in Figure 16.
Figure 15. Circuit for Missing-Pulse Detector
V
CC
(5 V to 15 V)
DISCH
OUT
VCC
RESET
RLRA
A5T3644
C
THRES
GND
CONT
TRIG
Input
0.01 µF
ÏÏÏ
Output
48
3
7
6
2
5
1
Pin numbers shown are shown for the D, JG, P, PS, and PW packages
.
Figure 16. Completed-Timing Waveforms
for Missing-Pulse Detector
Time − 0.1 ms/div
Voltage − 2 V/div
ÏÏÏÏÏ
ÏÏÏÏÏ
ÏÏÏÏÏ
ÏÏÏÏÏ
VCC = 5 V
RA = 1 k
C = 0.1 µF
See Figure 15
Capacitor Voltage
ÏÏÏÏÏ
ÏÏÏÏÏ
Output Voltage
Input Voltage
  
 
SLFS022E − SEPTEMBER 1973 − REVISED MARCH 2004
13
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
APPLICATION INFORMATION
frequency divider
By adjusting the length of the timing cycle, the basic circuit of Figure 9 can be made to operate as a frequency
divider. Figure 17 shows a divide-by-three circuit that makes use of the fact that retriggering cannot occur during
the timing cycle.
Voltage − 2 V/div
Time − 0.1 ms/div
Capacitor Voltage
Output Voltage
Input Voltage
ÏÏÏÏÏ
ÏÏÏÏÏ
ÏÏÏÏÏ
ÏÏÏÏÏ
VCC = 5 V
RA = 1250
C = 0.02 µF
See Figure 9
Figure 17. Divide-by-Three Circuit Waveforms
pulse-width modulation
The operation of the timer can be modified by modulating the internal threshold and trigger voltages, which is
accomplished by applying an external voltage (or current) to CONT. Figure 18 shows a circuit for pulse-width
modulation. A continuous input pulse train triggers the monostable circuit, and a control signal modulates the
threshold voltage. Figure 19 shows the resulting output pulse-width modulation. While a sine-wave modulation
signal is shown, any wave shape could be used.
  
 
SLFS022E − SEPTEMBER 1973 − REVISED MARCH 2004
14 POST OFFICE BOX 655303 DALLAS, TEXAS 75265
APPLICATION INFORMATION
THRES
GND C
RA
RL
VCC (5 V to 15 V)
Output
DISCH
OUT
VCC
RESET
TRIG
CONT
Modulation
Input
(see Note A)
Clock
Input
NOTE A: The modulating signal can be direct or capacitively coupled
to CONT. For direct coupling, the effects of modulation
source voltage and impedance on the bias of the timer
should be considered.
48
3
7
6
2
5
Pin numbers shown are for the D, JG, P, PS, and PW packages.
1
Figure 18. Circuit for Pulse-Width Modulation
Voltage − 2 V/div
Time − 0.5 ms/div
ÏÏÏÏÏÏ
Capacitor Voltage
ÏÏÏÏÏ
ÏÏÏÏÏ
Output Voltage
ÏÏÏÏÏÏ
ÏÏÏÏÏÏ
Clock Input Voltage
ÏÏÏÏ
ÏÏÏÏ
ÏÏÏÏ
RA = 3 k
C = 0.02 µF
RL = 1 k
See Figure 18
ÏÏÏÏÏÏÏÏ
ÏÏÏÏÏÏÏÏ
Modulation Input Voltage
Figure 19. Pulse-Width-Modulation Waveforms
pulse-position modulation
As shown in Figure 20, any of these timers can be used as a pulse-position modulator. This application
modulates the threshold voltage and, thereby, the time delay, of a free-running oscillator. Figure 21 shows a
triangular-wave modulation signal for such a circuit; however, any wave shape could be used.
RB
Modulation
Input
(see Note A) CONT
TRIG
RESET VCC
OUT
DISCH
VCC (5 V to 15 V)
RLRA
C
GND
THRES
NOTE A: The modulating signal can be direct or capacitively coupled
to CONT. For direct coupling, the effects of modulation
source voltage and impedance on the bias of the timer
should be considered.
Pin numbers shown are for the D, JG, P, PS, and PW packages.
48
3
7
6
2
5
Output
Figure 20. Circuit for Pulse-Position Modulation Figure 21. Pulse-Position-Modulation Waveforms
Voltage − 2 V/div
ÏÏÏÏÏ
ÏÏÏÏÏ
ÏÏÏÏÏ
ÏÏÏÏÏ
RA = 3 k
RB = 500
RL = 1 k
See Figure 20
ÏÏÏÏÏÏ
ÏÏÏÏÏÏ
Capacitor Voltage
ÏÏÏÏÏ
ÏÏÏÏÏ
Output Voltage
ÏÏÏÏÏÏÏÏ
ÏÏÏÏÏÏÏÏ
Modulation Input Voltage
Time − 0.1 ms/div
  
 
SLFS022E − SEPTEMBER 1973 − REVISED MARCH 2004
15
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
APPLICATION INFORMATION
sequential timer
Many applications, such as computers, require signals for initializing conditions during start-up. Other
applications, such as test equipment, require activation of test signals in sequence. These timing circuits can
be connected to provide such sequential control. The timers can be used in various combinations of astable
or monostable circuit connections, with or without modulation, for extremely flexible waveform control. Figure 22
shows a sequencer circuit with possible applications in many systems, and Figure 23 shows the output
waveforms.
S
VCC
RESET VCC
OUT
DISCH
GND
CONT
TRIG
48
3
7
6
1
5
2
THRES
RC
CC
0.01
CC = 14.7 µF
RC = 100 kOutput C
RESET VCC
OUT
DISCH
GND
CONT
TRIG
48
3
7
6
1
5
2
THRES
RB33 k
0.001
0.01
µF
CB = 4.7 µF
RB = 100 k
Output BOutput A
RA = 100 k
CA = 10 µF
µF
0.01
µF
0.001
33 k
RA
THRES
2
5
1
6
7
3
84
TRIG
CONT
GND
DISCH
OUT
VCC
RESET
µF
µF
CB
CA
Pin numbers shown are for the D, JG, P, PS, and PW packages.
NOTE A: S closes momentarily at t = 0.
Figure 22. Sequential Timer Circuit
Voltage − 5 V/div
t − Time − 1 s/div
ÏÏÏÏÏ
See Figure 22
ÏÏÏÏ
Output A
ÏÏÏÏ
ÏÏÏÏ
Output B
ÏÏÏÏ
Output C
ÏÏ
ÏÏ
t = 0
ÏÏÏÏÏ
twC = 1.1 RCCC
ÏÏÏ
twC
ÏÏÏÏÏÏ
twB = 1.1 RBCB
ÏÏÏÏÏ
twA = 1.1 RACA
ÏÏ
ÏÏ
twA
ÏÏ
ÏÏ
twB
Figure 23. Sequential Timer Waveforms
PACKAGING INFORMATION
Orderable Device Status (1) Package
Type Package
Drawing Pins Package
Qty Eco Plan (2) Lead/Ball Finish MSL Peak Temp (3)
JM38510/10901BPA ACTIVE CDIP JG 8 1 TBD A42 SNPB N / A for Pkg Type
NE555D ACTIVE SOIC D 8 75 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
NE555DE4 ACTIVE SOIC D 8 75 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
NE555DG4 ACTIVE SOIC D 8 75 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
NE555DR ACTIVE SOIC D 8 2500 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
NE555DRE4 ACTIVE SOIC D 8 2500 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
NE555DRG4 ACTIVE SOIC D 8 2500 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
NE555P ACTIVE PDIP P 8 50 Pb-Free
(RoHS) CU NIPDAU N / A for Pkg Type
NE555PE4 ACTIVE PDIP P 8 50 Pb-Free
(RoHS) CU NIPDAU N / A for Pkg Type
NE555PSLE OBSOLETE SO PS 8 TBD Call TI Call TI
NE555PSR ACTIVE SO PS 8 2000 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
NE555PSRE4 ACTIVE SO PS 8 2000 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
NE555PW ACTIVE TSSOP PW 8 150 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
NE555PWE4 ACTIVE TSSOP PW 8 150 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
NE555PWR ACTIVE TSSOP PW 8 2000 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
NE555PWRE4 ACTIVE TSSOP PW 8 2000 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
NE555Y OBSOLETE 0 TBD Call TI Call TI
SA555D ACTIVE SOIC D 8 75 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
SA555DE4 ACTIVE SOIC D 8 75 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
SA555DG4 ACTIVE SOIC D 8 75 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
SA555DR ACTIVE SOIC D 8 2500 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
SA555DRE4 ACTIVE SOIC D 8 2500 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
SA555DRG4 ACTIVE SOIC D 8 2500 Green (RoHS &
no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
SA555P ACTIVE PDIP P 8 50 Pb-Free
(RoHS) CU NIPDAU N / A for Pkg Type
SA555PE4 ACTIVE PDIP P 8 50 Pb-Free
(RoHS) CU NIPDAU N / A for Pkg Type
SE555D ACTIVE SOIC D 8 75 TBD CU NIPDAU Level-1-220C-UNLIM
SE555DR ACTIVE SOIC D 8 2500 TBD CU NIPDAU Level-1-220C-UNLIM
PACKAGE OPTION ADDENDUM
www.ti.com 24-Jan-2006
Addendum-Page 1
Orderable Device Status (1) Package
Type Package
Drawing Pins Package
Qty Eco Plan (2) Lead/Ball Finish MSL Peak Temp (3)
SE555FKB ACTIVE LCCC FK 20 1 TBD POST-PLATE N / A for Pkg Type
SE555JG ACTIVE CDIP JG 8 1 TBD A42 SNPB N / A for Pkg Type
SE555JGB ACTIVE CDIP JG 8 1 TBD A42 SNPB N / A for Pkg Type
SE555N OBSOLETE PDIP N 8 TBD Call TI Call TI
SE555P ACTIVE PDIP P 8 50 Pb-Free
(RoHS) CU NIPDAU N / A for Pkg Type
(1) The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in
a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check
http://www.ti.com/productcontent for the latest availability information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and
package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS
compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)
(3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder
temperature.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is
provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the
accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take
reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on
incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited
information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI
to Customer on an annual basis.
PACKAGE OPTION ADDENDUM
www.ti.com 24-Jan-2006
Addendum-Page 2
MECHANICAL DATA
MCER001A – JANUARY 1995 – REVISED JANUAR Y 1997
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
JG (R-GDIP-T8) CERAMIC DUAL-IN-LINE
0.310 (7,87)
0.290 (7,37)
0.014 (0,36)
0.008 (0,20)
Seating Plane
4040107/C 08/96
5
4
0.065 (1,65)
0.045 (1,14)
8
1
0.020 (0,51) MIN
0.400 (10,16)
0.355 (9,00)
0.015 (0,38)
0.023 (0,58)
0.063 (1,60)
0.015 (0,38)
0.200 (5,08) MAX
0.130 (3,30) MIN
0.245 (6,22)
0.280 (7,11)
0.100 (2,54)
0°–15°
NOTES: A. All linear dimensions are in inches (millimeters).
B. This drawing is subject to change without notice.
C. This package can be hermetically sealed with a ceramic lid using glass frit.
D. Index point is provided on cap for terminal identification.
E. Falls within MIL STD 1835 GDIP1-T8
MECHANICAL DATA
MLCC006B – OCTOBER 1996
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
FK (S-CQCC-N**) LEADLESS CERAMIC CHIP CARRIER
4040140/D 10/96
28 TERMINAL SHOWN
B
0.358
(9,09)
MAX
(11,63)
0.560
(14,22)
0.560
0.458
0.858
(21,8)
1.063
(27,0)
(14,22)
A
NO. OF
MINMAX
0.358
0.660
0.761
0.458
0.342
(8,69)
MIN
(11,23)
(16,26)
0.640
0.739
0.442
(9,09)
(11,63)
(16,76)
0.962
1.165
(23,83)
0.938
(28,99)
1.141
(24,43)
(29,59)
(19,32)(18,78)
**
20
28
52
44
68
84
0.020 (0,51)
TERMINALS
0.080 (2,03)
0.064 (1,63)
(7,80)
0.307
(10,31)
0.406
(12,58)
0.495
(12,58)
0.495
(21,6)
0.850
(26,6)
1.047
0.045 (1,14)
0.045 (1,14)
0.035 (0,89)
0.035 (0,89)
0.010 (0,25)
12
1314151618 17
11
10
8
9
7
5
432
0.020 (0,51)
0.010 (0,25)
6
12826 27
19
21
B SQ
A SQ 22
23
24
25
20
0.055 (1,40)
0.045 (1,14)
0.028 (0,71)
0.022 (0,54)
0.050 (1,27)
NOTES: A. All linear dimensions are in inches (millimeters).
B. This drawing is subject to change without notice.
C. This package can be hermetically sealed with a metal lid.
D. The terminals are gold plated.
E. Falls within JEDEC MS-004
MECHANICAL DATA
MPDI001A – JANUARY 1995 – REVISED JUNE 1999
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
P (R-PDIP-T8) PLASTIC DUAL-IN-LINE
8
4
0.015 (0,38)
Gage Plane
0.325 (8,26)
0.300 (7,62)
0.010 (0,25) NOM
MAX
0.430 (10,92)
4040082/D 05/98
0.200 (5,08) MAX
0.125 (3,18) MIN
5
0.355 (9,02)
0.020 (0,51) MIN
0.070 (1,78) MAX
0.240 (6,10)
0.260 (6,60)
0.400 (10,60)
1
0.015 (0,38)
0.021 (0,53)
Seating Plane
M
0.010 (0,25)
0.100 (2,54)
NOTES: A. All linear dimensions are in inches (millimeters).
B. This drawing is subject to change without notice.
C. Falls within JEDEC MS-001
For the latest package information, go to http://www.ti.com/sc/docs/package/pkg_info.htm
MECHANICAL DATA
MTSS001C – JANUARY 1995 – REVISED FEBRUARY 1999
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
PW (R-PDSO-G**) PLASTIC SMALL-OUTLINE PACKAGE
14 PINS SHOWN
0,65 M
0,10
0,10
0,25
0,50
0,75
0,15 NOM
Gage Plane
28
9,80
9,60
24
7,90
7,70
2016
6,60
6,40
4040064/F 01/97
0,30
6,60
6,20
80,19
4,30
4,50
7
0,15
14
A
1
1,20 MAX
14
5,10
4,90
8
3,10
2,90
A MAX
A MIN
DIM PINS **
0,05
4,90
5,10
Seating Plane
0°–8°
NOTES: A. All linear dimensions are in millimeters.
B. This drawing is subject to change without notice.
C. Body dimensions do not include mold flash or protrusion not to exceed 0,15.
D. Falls within JEDEC MO-153
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