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BAS31 — Small Signal Diode
© 2001 Fairchild Semiconductor Corporation www.fairchildsemi.com
BAS31 Rev. 1.3
February 2015
BAS31
Small Signal Diode
Ordering Information
Absolute Maximum Ratings(1), (2)
Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be opera-
ble above the re co mmen ded operating conditions and s tres si ng the parts to these level s i s not recommended. In addi-
tion, extended exposure to stresses above the recommended operating conditions may affect device reliability. The
absolute maximum ratings are stress ratings only. Values are at TA = 25°C unless otherwise noted.
Notes:
1. These ratings are based on a maximum junction temperature of 150°C.
2. These are steady-state limits. Fairchild Semiconductor should be consulted on applic ations involving pulsed or
low-duty-cycle operations.
Part Number Top Mark Package Packing Method
BAS31 L21 SOT-23 3L Tape and Reel, 7 inch Reel, 3000 pcs
BAS31_D87Z L21 SOT-23 3L Tape and Reel, 13 inch Reel, 10000 pcs
Symbol Parameter Value Unit
VRRM Maximum Repetitive Reverse Voltage 120 V
IF(AV) Average Rectified Forward Current 200 mA
IFSM Non-Repetitive Peak Forward
Surge Current Pulse Width = 1.0 second 1.0 A
Pulse Width = 1. 0 microsecond 2.0
TSTG Storage Temperature Range -55 to +150 °C
TJOperating Junction Te mperature 150 °C
12
3
L21
3
1
2
SOT-23
12
3
Connection Diagram
BAS31 — Small Signal Diode
© 2001 Fairchild Semiconductor Corporation www.fairchildsemi.com
BAS31 Rev. 1.3 2
Thermal Characteristics
Values are at TA = 25°C unless otherwise noted.
Electrical Characteristics
Values are at TA = 25°C unless otherwise noted.
Symbol Parameter Value Unit
PDPower Dissipation 350 mW
RθJA Thermal Resistance, Junction-to-Ambient 357 °C/W
Symbol Parameter Conditions Min. Max. Unit
VRBreakdown Voltage IR = 1.0 mA 120 V
VFForward Voltage
IF = 10 mA 750 mV
IF = 50 mA 840 mV
IF = 100 mA 900 mV
IF = 200 mA 1.00 V
IF = 400 mA 1.25 V
IRReverse Current VR = 90 V 100 nA
VR = 90 V, TA = 150°C 100 μA
CTTotal Capacitance VR = 0, f = 1.0 MHz 35 pF
trr Reverse Recovery Time IF = IR = 30 mA, IRR = 3.0 mA,
RL = 100 Ω50 ns
BAS31 — Small Signal Diode
© 2001 Fairchild Semiconductor Corporation www.fairchildsemi.com
BAS31 Rev. 1.3 3
Typical Performance Characteristics
Figure 1. Reverse Voltage vs. Reverse Current
BV - 1.0 to 100 μAFigure 2. Reverse Current vs. Reverse Voltage
IR - 55 to 205 V
Figure 3. Reverse Current vs. Reverse Voltage
IR - 180 to 255 V Figure 4. Forward Voltage vs. Forward Current
VF - 1.0 to 100 μA
Figure 5. Forward Voltage vs. Forward Current
VF - 0.1 to 10 mA Figure 6. Forward Voltage vs. Forward Current
VF - 10 to 800 mA
3 5 10 20 30 50 100
275
300
325
I - REVERSE CURRENT (uA)
V - REVERSE VOLTAGE (V)
R
R
Ta= 25°C
VR
GENERAL RULE: The Reverse Current of a diode will approximately
double for every ten (10) Degree C increase in Temperature
55 75 95 115 135 155 175 195
0
10
20
30
40
50
V - REVERSE VOLTAGE (V)
I - REVERSE CURRENT (nA)
R
R
Ta= 25°C
GENERAL RULE: The Reverse Current of a diode will approximately
double for every ten Degree C increase in Temperature
180 200 220 240
20
30
40
50
60
70
80
90
100
V - REVERSE VOLTAGE (V)
I - REVERSE CURRENT (nA)
R
R
Ta= 25°C
255
IR
1 2 3 5 10 20 30 50 100
250
300
350
400
450
I - FORWARD CURRENT (uA)
V - FORWARD VOLTAGE (mV)
F
F
Ta= 25°C
VF
0.1 0.2 0.3 0.5 1 2 3 5 10
450
500
550
600
650
700
I - FORWARD CURRENT (mA)
V - FORWARD VOLTAGE (mV)
F
F
725 Ta= 25°C
V
F
10 20 30 50 100 200 300 500
0.7
0.8
0.9
1
1.1
1.2
1.3
1.4
I - FORWARD CURRENT (mA)
V - FORWARD VOLTAGE (mV)
F
F
800
Ta= 25°C
V
F
BAS31 — Small Signal Diode
© 2001 Fairchild Semiconductor Corporation www.fairchildsemi.com
BAS31 Rev. 1.3 4
Typical Performance Characteristics (Continued)
Figure 7. Forward Voltage vs. Ambient Temp erature
VF - 1.0 μA - 10 mA (- 40 to +80°C) Figure 8. Capacitance vs. Reverse Voltage
Figure 9. Reverse Recovery Time vs.
Reverse Recovery Current (Irr) Figure 10. Average Rectified Current(IO) and
Forward Current (IF) vs. Ambient Temperature(TA)
Figure 11. Power Derating Curve
0.001 0.003 0.01 0.03 0.1 0.3 1 3 10
200
400
600
800
I - FORWARD CURRENT (mA)
V - FORWARD VOLTAGE (mV)
F
F
Ta= 25°C
Ta= +80°C
Ta= -40°C
VF
0 2 4 6 8 10 12 14
0.8
0.9
1
1.1
1.2
1.3
REVERSE VOLTAGE (V)
CAPACITANCE (pF)
Ta= 25°C
15
11.522.53
20
30
40
50
Irr - REVERSE RECOVERY CURRENT (mA)
REVERSE RECOVERY (nS)
IF = IR = 30 mA
Rloop = 100 Ohms
050100150
0
100
200
300
400
500
T - AMBIENT TEMPERATURE ( C)
I - CURRENT (mA)
I - FORWARD CURRENT STEADY STATE - mA
o
R
Io - AVERAGE RECTIFIED CURRENT - mA
A
0 50 100 150 200
0
100
200
300
400
500
I - AVERAGE TEMPERATURE ( C)
P - POWER DISSIPATION (mW)
O
D
o
SOT-23 Pkg
BAS31 — Small Signal Diode
© 2001 Fairchild Semiconductor Corporation www.fairchildsemi.com
BAS31 Rev. 1.3 5
Physical Dimensions
Figure 12. 3-LEAD, SOT23, JEDEC TO-236, LOW PROFILE
LAND PATTERN
RECOMMENDATION
NOTES: UNLESS OTHERWISE SPECIFIED
A) REFERENCE JEDEC REGISTRATION
TO-236, VARIATION AB, ISSUE H.
B) ALL DIMENSIONS ARE IN MILLIMETERS.
C) DIMENSIONS ARE INCLUSIVE OF BURRS,
MOLD FLASH AND TIE BAR EXTRUSIONS.
D) DIMENSIONING AND TOLERANCING PER
ASME Y14.5M - 1994.
E) DRAWING FILE NAME: MA03DREV10
3
12
SEE DETAIL A
SEATING
PLANE
SCALE: 2X
GAGE PLANE
(0.55)
(0.93)
1.20 MAX
C
0.10
0.00
0.10 C
2.40±0.30
2.92±0.20
1.30+0.20
-0.15
0.60
0.37
0.20 A B
1.90
0.95
(0.29)
0.95
1.40
2.20
1.00
1.90
0.25
0.23
0.08
0.20 MIN
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