®
DB3 DB4 SMDB3
DIAC
FEATURES
s
s
V
BO
: 32V and 40V
LOW BREAKOVER CURRENT
DESCRIPTION
Functioning as a trigger diode with a fixed voltage
reference, the DB3/DB4 series can be used in
conjunction with triacs for simplified gate control
circuits or as a starting element in fluorenscent
lamp ballasts.
A new surface mount version is now available in
SOT-23 package, providing reduced space and
compatibility with automatic pick and place
equipment.
DO-35
(DB3 and DB4)
2
3
1
SOT-23
(SMDB3)*
Pin 1 and 3 must be shorted
together
ABSOLUTE MAXIMUM RATINGS
(limiting values)
Symbol
I
TRM
Parameter
Repetitive peak on-state current
tp = 20
µs
F= 120 Hz
SMDB3
DB3 / DB4
Tstg
Tj
Storage temperature range
Operating junction temperature range
Value
1.00
2.00
- 40 to + 125
°C
Unit
A
Note: * SMDB3 indicated as Preliminary spec as product is still in development stage.
October 2001 - Ed: 2B
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DB3 DB4 SMDB3
ELECTRICAL CHARACTERISTICS
(Tj = 25°C unless otherwise specified)
Symbol
V
BO
Parameter
Breakover voltage *
Test Conditions
C = 22nF **
MIN.
TYP.
MAX.
I V
BO1
- V
BO2
I
∆
V
V
O
I
BO
tr
I
R
I
P
Breakover voltage
symmetry
Dynamic breakover
voltage *
Output voltage *
Breakover current *
Rise time *
Leakage current *
Peak current *
C = 22nF **
V
BO
and V
F
at 10mA
see diagram 2
(R=20Ω)
C = 22nF **
see diagram 3
V
R
= 0.5 V
BO
max
see diagram 2 (Gate)
MAX.
MIN.
MIN.
MAX.
MAX.
MAX.
MIN.
10
10
10
0.50
1
1
SMDB3
28
32
36
3
5
5
50
2
10
0.30
DB3
28
32
36
DB4
35
40
45
V
V
V
µA
µs
µA
A
Unit
V
* Applicable to both forward and reverse directions.
** Connected in parallel to the device.
PRODUCT SELECTOR
Part Number
SMDB3
DB3
DB4
V
BO
28 - 36
28 - 36
35 - 45
Package
SOT-23
DO-35
DO-35
ORDERING INFORMATION
SM DB 3
Surface
Mount
Version
Diac Series
Breakover voltage
3: V
BO
typ = 32V
4: V
BO
typ = 40V
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DB3 DB4 SMDB3
OTHER INFORMATION
Part Number
SMDB3
DB3
DB4
DB3
DB3 (Blue Body Coat)
DB4 (Blue Body Coat)
Marking
Weight
0.01 g
0.15 g
0.15 g
Base Quantity
3000
5000
5000
Packing Mode
Tape & Reel
Tape & Reel
Tape & Reel
Diagram 1:
Voltage - current characteristic curve.
Diagram 2:
Test circuit.
10 kΩ
500 kΩ
D.U.T
Rs=0
+ IF
10mA
220 V
50 Hz
C=0.1µF
Vo
I
P
T410
R=20
Ω
IBO
IB
0,5 VBO
V
VF
VBO
-V
+ V
Diagram 3:
Rise time measurement.
l
p
90 %
- IF
10 %
tr
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DB3 DB4 SMDB3
Fig. 1:
Relative variation of VBO versus junction
temperature (typical values).
VBO [Tj] / VBO [Tj=25°C]
1.10
1.05
1.00
0.95
0.90
0.85
Tj(°C)
0.80
25
50
75
100
125
SMDB3
DB3/DB4
Fig. 2:
Repetitive peak pulse current versus pulse
duration (maximum values).
ITRM(A)
20.0
10.0
DB3/DB4
F=120Hz
Tj initial=25°C
1.0
SMDB3
tp(µs)
0.1
1
10
100
Fig. 3:
Time duration while current pulse is higher
50mA versus C and Rs (typical values).
tp(µs)
40
Tj=25°C
35
30
25
20
15
10
5
0
10
20
50
10Ω
0Ω
33Ω
47Ω
68Ω
22Ω
C(nF)
200
500
100
PACKAGE MECHANICAL DATA
(in millimeters)
DO-35
REF.
C
A
C
DIMENSIONS
Millimeters
Min.
Max.
4.50
2.00
O
B
/
Inches
Min.
0.120
0.060
1.102
Max.
0.177
0.079
A
B
O
D
/
O
D
/
3.05
1.53
28.00
0.458
C
D
0.558
0.018
0.022
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DB3 DB4 SMDB3
PACKAGE MECHANICAL DATA
(in millimeters)
SOT-23
A
E
REF.
Min.
DIMENSIONS
Millimeters
Max.
1.4
0.1
0.51
0.18
3.04
1.05
2.1
1.6
2.75
Inches
Min.
0.035
0
0.012
0.003
0.108
0.033
0.067
0.047
0.083
Max.
0.055
0.004
0.02
0.007
0.12
0.041
0.083
0.063
0.108
e
B
e1
D
A
A1
B
0.89
0
0.3
0.085
2.75
0.85
1.7
1.2
2.1
S
A1
c
D
e
L
e1
H
E
H
L
c
0.6 typ.
0.35
0.65
0.024 typ.
0.014
0.026
S
FOOTPRINT
0.9
0.035
0.9
0.035
1.1
0.043
2.35
0.92
1.9
0.075
1.45
0.037
mm
inch
0.9
0.035
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of
use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by
implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to
change without notice. This publication supersedes and replaces all information previously supplied.
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proval of STMicroelectronics.
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1.1
0.043