Datasheet
SMBJ Characteristics
Doc ID 5616 Rev 10 5/10
Figure 6. Junction capacitance versus 
reverse applied voltage for 
unidirectional types (typical values)
Figure 7. Junction capacitance versus 
reverse applied voltage for 
bidirectional types (typical values)
10
100
1000
10000
1 10 100 1000
C(pF)
F=1 MHz
V
osc
=30 mV
RMS
T
j
=25 °C
SMBJ5.0A
SMBJ12A
SMBJ24A
SMBJ40A
SMBJ85A
SMBJ188A
V
R
(V)
10
100
1000
10000
1 10 100 1000
C(pF)
F=1 MHz
V
osc
=30 mV
RMS
T
j
=25 °C
SMBJ5.0CA
SMBJ12CA
SMBJ24CA
SMBJ40CA
SMBJ85CA
SMBJ188CA
V
R
(V)
Figure 8. Peak forward voltage drop 
versus peak forward current
(typical values)
Figure 9. Relative variation of thermal 
impedance, junction to ambient, 
versus pulse duration
Figure 10. Thermal resistance, junction to 
ambient, versus copper surface 
under each lead
Figure 11. Leakage current versus junction 
temperature (typical values)
I
FM
(A)
1.0E-02
1.0E-01
1.0E+00
1.0E+01
1.0E+02
0.0 0.5 1.0 1.5 2.0 2.5 3.0
T
j
=25 °C
T
j
=125 °C
V
FM
(V)
0.01
0.10
1.00
1.0E-03 1.0E-02 1.0E-01 1.0E+00 1.0E+01 1.0E+02 1.0E+03
Z
th(j-a)
/R
th(j-a)
t
P
(s)
Recommended pad layout
PCB FR4, copper thickness = 35 µm
0
10
20
30
40
50
60
70
80
90
100
110
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
R (°C/W)
th(J-A)
S
CU
(cm²)
PCB FR4, copper thickness = 35 µm
1.E-01
1.E+00
1.E+01
1.E+02
1.E+03
25 50 75 100 125 150
V
R
=V
RM
V
RM
≥ 10 V
V
R
=V
RM
V
RM
<10V
T
j
(°C)
I
R
(nA)










