July 1998
.
LOW TURN OFF TIME
.
MAXIMUM
OPERATING
FREQUENCY
GREATER THAN 500kHz
.
TIMING FROM MICROSECONDS TO HOURS
.
OPERATES
IN
BOTH
ASTABLE
AND
MONOSTABLE MODES
.
HIGH OUTPUT CURRENT CAN SOURCE OR
SINK 200mA
.
ADJUSTABLE DUTY CYCLE
.
TTL COMPATIBLE
.
TEMPERATURE STABILITY OF 0.005%
PER
o
C
ORDER CODES
Part
Number
Temperature
Range
Pakcage
N
D
NE556
0
o
C, 70
o
C
SA556
40
o
C, 105
o
C
SE556
55
o
C, 125
o
C
DESCRIPTION
The NE556 dual monolithic timing circuit is a highly
stable controller capable of producing accurate time
delays or oscillation. In the time delay mode of op-
eration, the time is precisely controlled by one exter-
nal resistor and capacitor. For a stable operation as
an oscillator, the freerunningfrequencyand the duty
cycle are both accurately controlled with two exter-
nal resistors and one capacitor. The circuit may be
triggered and reset on falling waveforms, and the
output structure can source or sink up to 200mA.
GENERAL PURPOSE DUAL BIPOLAR TIMERS
N
DIP14
(Plastic Package)
D
SO14
(Plastic Micropackage)
Trigge r
Output
C ontrol Voltage
4
8
5
6
7
9
10
11
12
13
14
Trigge r
Thres hold
Discha rge
Re s e t
Output
Discha rge
GND
1
2
3
Thre s hold
C ontrol Voltage
Re s e t
CC
V
PIN CONNECTIONS (top view)
NE556
SA556 - SE556
1/9
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Value
Unit
V
cc
Supply Voltage
18
V
T
oper
Operating Free Air Temperature Range
for NE556
for SA556
for SE556
0 to 70
40 to 105
55 to 125
C
T
j
Junction Temperature
150
C
T
stg
Storage Temperature Range
65 to 150
C
THRES HOLD
COMP
5 k
5 k
5 k
TRIGGER
R
FLIP-FLOP
S
Q
DISCHARGE
OUT
INHIBIT/
RESET
RES ET
COMP
S
+
CONTROL VOLTAGE
V
C C
1/2 NE556
BLOCK DIAGRAM
OUTPUT
CONTROL
VOLTAGE
THRESHOLD
COMPARATOR
V
CC
R 1
4. 7k
R 2
8 30
Q5
Q6
Q7
Q8
Q9
R 3
4 .7k
R4
1k
R8
5 k
Q1
Q2
Q3
Q4
Q10
Q11 Q12
Q1 3
THRESHOLD
TR IGGER
R ES ET
DISC HARGE
G N D
2
4
7
1
Q14
Q1 5
R 5
1 0k
R6
1 00 k
R 7
1 0 0k
R1 0
5 k
Q17
Q16
Q18
R9
5 k
D2
R16
100
R15
4.7k
R14
220
Q24
Q23
R17
4.7k
3
Q22
13
D1
Q19
Q2 0
Q21
R12
6.8k
5
TR IGGER C OMPARATOR
FLIP FLOP
R 1 1
5k
3.9 k
SCHEMATIC DIAGRAM
NE556/SA556/SE556
2/9
Notes :
1. Supply current when output is high is typically 1mA less.
2. Tested at V
CC
= +5V and V
CC
= +15V.
3. This will determine the maximum value of R
A
+ R
B
for +15V operation the max total is R = 20M
and for 5V operation
the max total R = 3.5M
.
4. Specified with trigger input high.
ELECTRICAL CHARACTERISTICS
T
amb
= +25
o
C, V
CC
= +5V to +15V (unless otherwise specified)
Symbol
Parameter
SE556
NE556 - SA556
Unit
Min.
Typ.
Max.
Min.
Typ.
Max.
I
CC
Supply Current (R
L
) (- note 1) - (2 timers)
Low State
V
CC
= +5V
V
CC
= +15V
High State
V
CC
= 5V
6
20
4
10
24
6
20
4
12
30
mA
Timing Error (monostable)
(R
A =
2k to 100k
, C = 0.1
F)
Initial Accuracy - (note 2)
Drift with Temperature
Drift with Supply Voltage
0.5
30
0.05
2
100
0.2
1
50
0.1
3
0.5
%
ppm/
C
%/V
Timing Error (astable)
(R
A
, R
B
= 1k
to 100k
, C = 0.1
F,
V
CC
= +15V)
Initial Accuracy - (note 2)
Drift with Temperature
Drift with Supply Voltage
1.5
90
0.15
2.25
150
0.3
%
ppm/
C
%/V
V
CL
Control Voltage level
V
CC
= +15V
V
CC
= +5V
9.6
2.9
10
3.33
10.4
3.8
9
2.6
10
3.33
11
4
V
V
th
Threshold Voltage
V
CC
= +15V
V
CC
= +5V
9.4
2.7
10
3.33
10.6
4
8.8
2.4
10
3.33
11.2
4.2
V
I
th
Threshold Current - (note 3)
0.1
0.25
0.1
0.25
A
V
trig
Trigger Voltage
V
CC
= +15V
V
CC
= +5V
4.8
1.45
5
1.67
5.2
1.9
4.5
1.1
5
1.67
5.6
2.2
V
I
trig
Trigger Current (V
trig
= 0V)
0.5
0.9
0.5
2.0
A
V
reset
Reset Voltage - (note 4)
0.4
0.7
1
0.4
0.7
1
V
I
reset
Reset Current
V
reset
= +0.4V
V
reset
= 0V
0.1
0.4
0.4
1
0.1
0.4
0.4
1.5
mA
V
OL
Low Level Output Voltage
V
CC
= +15V,
I
O(sink)
= 10mA
I
O(sink)
= 50mA
I
O(sink)
= 100mA
I
O(sink)
= 200mA
V
CC
= +5V,
I
O(sink)
= 8mA
I
O(sink)
= 5mA
0.1
0.4
2
2.5
0.1
0.05
0.15
0.5
2.2
0.25
0.2
0.1
0.4
2
2.5
0.3
0.25
0.25
0.75
2.5
0.4
0.35
V
V
OH
High Level Output Voltage
V
CC
= +15V,
I
O(source)
= 200mA
I
O(source)
= 100mA
V
CC
= +5V,
I
O(source)
= 100mA
13
3
12.5
13.3
3.3
12.75
2.75
12.5
13.3
3.3
V
OPERATING CONDITIONS
Symbol
Parameter
SE556
NE556 - SA556
Unit
V
CC
Supply Voltage
4.5 to 18
4.5 to 18
V
V
th
, V
trig
, V
cl
, V
reset
Maximum Input Voltage
V
CC
V
CC
V
NE556/SA556/SE556
3/9
Notes :
5. No protection against excessive Pin 7 current is necessary, providing the package dissipation rating will not be exceeded.
6. Time mesaured from a positive going input pulse from 0 to 0.8x V
CC
into the threshold to the drop from high to low of the
output trigger is tied to treshold.
ELECTRICAL CHARACTERISTICS (continued)
Symbol
Parameter
SE556
NE556 - SA556
Unit
Min.
Typ.
Max.
Min.
Typ.
Max.
I
dis (off)
Discharge Pin Leakage Current
(output high) (V
dis
= 10V)
20
100
20
100
nA
V
dis(sat)
Discharge pin Saturation Voltage
(output low) - (note 5)
V
CC
= +15V, I
dis
= 15mA
V
CC
= +5V, I
dis
= 4.5mA
180
80
480
200
180
80
480
200
mV
t
r
t
f
Output Rise Time
Output Fall Time
100
100
200
200
100
100
300
300
ns
t
off
Turn off Time - (note 6) (V
reset
= V
CC
)
0.5
0.5
s
Figure 1 : Minimum Pulse Width Required for
Trigering
Figure 2 : Supply Current versus Supply Voltage
Figure 3 : Delay Time versus Temperature
Figure 4 : Low Output Voltage versus Output
Sink Current
NE556/SA556/SE556
4/9
Figure 5 : Low Output Voltage versus Output
Sink Current
Figure 6 : Low Output Voltage versus Output
Sink Current
Figure 7 : High Output Voltage Drop versus
Output
Figure 8 : Delay Time versus Supply Voltage
Figure 9 : Propagation Delay versus Voltage
Level of Trigger Value
NE556/SA556/SE556
5/9
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