BAS21T
Document number: DS30264 Rev. 10 - 2 1 of 3
www.diodes.com March 2009
© Diodes Incorporated
BAS21T
SURFACE MOUNT FAST SWITCHING DIODE
Features
• Ultra-Small Surface Mount Package
• Fast Switching Speed
• For General Purpose Switching Applications
• High Conductance
• Lead Free/RoHS Compliant (Note 3)
• "Green" Device (Notes 4 and 5)
Mechanical Data
• Case: SOT-523
• Case Material: Molded Plastic, "Green" Molding Compound,
Note 5. UL Flammability Classification Rating 94V-0
• Moisture Sensitivity: Level 1 per J-STD-020D
• Terminals: Solderable per MIL-STD-202, Method 208
• Lead Free Plating (Matte Tin Finish annealed over Alloy 42
leadframe)
• Polarity: See Diagram
• Marking Information: See Page 2
• Ordering Information: See Page 2
• Weight: 0.002 grams (approximate)
Maximum Ratings @TA = 25°C unless otherwise specified
Characteristic Symbol Value Unit
Repetitive Peak Reverse Voltage VRRM 250 V
Working Peak Reverse Voltage
DC Blocking Voltage VRWM
VR 200 V
RMS Reverse Voltage VR
(
RMS
)
141 V
Forward Continuous Current (Note 1) IFM 400 mA
Average Rectified Output Current (Note 1) IO 200 mA
Non-Repetitive Peak Forward Surge Current @ t = 1.0
μ
s
@ t = 1.0s IFSM 2.5
0.5 A
Repetitive Peak Forward Surge Current IFRM 625 mA
Thermal Characteristics
Characteristic Symbol Value Unit
Power Dissipation (Note 1) PD 150 mW
Thermal Resistance Junction to Ambient (Note 1) R
θ
JA 833 °C/W
Operating and Storage Temperature Range TJ, TSTG -65 to +150 °C
Electrical Characteristics @TA = 25°C unless otherwise specified
Characteristic Symbol Min Max Unit Test Condition
Reverse Breakdown Voltage (Note 2) V
(
BR
)
R 250 ⎯ V IR = 100μA
Forward Voltage VF ⎯ 1.0
1.25 V IF = 100mA
IF = 200mA
Reverse Current @ Rated DC Blocking Voltage (Note 2) IR ⎯ 100
15 nA
μA TJ = 25°C
TJ = 100°C
Total Capacitance CT ⎯ 5.0 pF VR = 0, f = 1.0MHz
Reverse Recovery Time trr ⎯ 50 ns IF = IR = 30mA,
Irr = 0.1 x IR, RL = 100Ω
Notes: 1. Device mounted on FR-4 PC board with recommended pad layout, which can be found on our website at
http://www.diodes.com/datasheets/ap02001.pdf.
2. Short duration pulse test used to minimize self-heating effect.
3. No purposefully added lead.
4. Diodes Inc.'s "Green" policy can be found on our website at http://www.diodes.com/products/lead_free/index.php.
5. Product manufactured with Date Code UO (week 40, 2007) and newer are built with Green Molding Compound. Product manufactured prior to Date
Code UO are built with Non-Green Molding Compound and may contain Halogens or Sb2O3 Fire Retardants.
TOP VIEW
SOT-523
Internal Schematic
TOP VIEW
BAS21T
Document number: DS30264 Rev. 10 - 2 2 of 3
www.diodes.com March 2009
© Diodes Incorporated
BAS21T
0100 200
200
150
50
100
0
T , AMBIENT TEMPERA TURE ( C)
Fig. 1 Power Derating Curve
A
°
P
,
P
O
WE
R
DISSI
P
A
T
I
O
N
(mW)
D
0.001
0.01
0.1
1
00.40.2 0. 6
I, I
N
S
T
A
N
T
A
N
E
O
U
S
F
O
R
WA
R
D
C
U
R
R
E
N
T
(A)
F
V , INSTANTANEOUS FORWARD VOLTAGE (V)
Fig. 2 Typi cal Forw ar d Ch ar acter istics
F
0.8 1.2
1.0 1.4
0.0001
0.01
0.001
0.1
1
10
100
050100 200150 250
V , INSTANTANEOUS REVERSE VOLTAGE (V)
Fig. 3 Typical Reverse Characteristics
R
T = -40ºC
A
T = 25ºC
A
T = 75ºC
A
T = 125ºC
A
T = 150ºC
A
T = 0ºC
A
0.0
0.5
1.0
1.5
3.5
3.0
2.5
2.0
4.0
010 20 4030
C
,
T
O
T
AL
C
A
P
A
C
I
T
AN
C
E (p
F
)
T
V , DC REVERSE VOLTAGE (V)
Fig. 4 Total Capacitance vs. Reverse Voltage
R
Ordering Information (Notes 5 & 6)
Part Number Case Packaging
BAS21T-7-F SOT-523 3000/Tape & Reel
Notes: 6. For packaging details, go to our website at http://www.diodes.com/datasheets/ap02007.pdf.
Marking Information
Date Code Key
Year 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012
Code M N P R S T U V W X Y Z
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Code 1 2 3 4 5 6 7 8 9 O N D
T3 = Product Type Marking Code
YM = Date Code Marking
Y = Year (ex: N = 2002)
M = Month (ex: 9 = September)
T3YM
BAS21T
Document number: DS30264 Rev. 10 - 2 3 of 3
www.diodes.com March 2009
© Diodes Incorporated
BAS21T
Package Outline Dimensions
Suggested Pad Layout
IMPORTANT NOTICE
Diodes Incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or other changes
without further notice to any product herein. Diodes Incorporated does not assume an y liability arising out of the application or use of any product
described herein; neither does it convey any license under its patent rights, nor the rights of others. The user of products in such applications shall
assume all risks of such use and will agree to hold Diodes Incorporated and all the companies whose products are represented on our website,
harmless against all damages. LIFE SUPPORT
Diodes Incorporated products are not authorized for use as critical components in life support devices or systems without the expressed written
approval of the President of Diodes Incorporated.
SOT-523
Dim Min Max Typ
A 0.15 0.30 0.22
B 0.75 0.85 0.80
C 1.45 1.75 1.60
D ⎯ ⎯ 0.50
G 0.90 1.10 1.00
H 1.50 1.70 1.60
J 0.00 0.10 0.05
K 0.60 0.80 0.75
L 0.10 0.30 0.22
M 0.10 0.20 0.12
N 0.45 0.65 0.50
α 0° 8° ⎯
All Dimensions in mm
Dimensions Value (in mm)
Z 1.8
X 0.4
Y 0.51
C 1.3
E 0.7
A
M
JL
D
BC
H
K
G
N
XE
Y
C
Z
