BAS21

Small Signal Diode, Single, 250 V, 400 mA, 1 V, 50 ns, 1 A

⚠️ Reference pricing provided. In case of supply shortages, we will connect you with our trusted procurement partners to ensure your project's continuity.

Manufacturer: DIODES INC.
Product type: Small Signal Diodes
Diode Configuration:Single; Repetitive Reverse Voltage Vrrm Max:250V; Forward Current If(AV):400mA; Forward Voltage VF Max:1V; Reverse Recovery Time trr Max:50ns; Forward Surge Current If
SVHC: No SVHC (25-Jun-2025)
No. of Pins: 3Pins
Product Range: BAS21
Qualification: -
Diode Mounting: Surface Mount
Diode Case Style: SOT-23
Diode Configuration: Single
Forward Voltage Max: 1V
Forward Surge Current: 1A
Reverse Recovery Time: 50ns
Average Forward Current: 400mA
Operating Temperature Max: 150°C
Repetitive Peak Reverse Voltage: 250V

Delivery and price
Units per pack	1500
Price	0.031 €
Current stock	1000+
Lead time	30 days

Datasheet

## _**4Switchin Diodes g**_ 

|**Type Number**|**Peak Repetitive**<br>**Reverse Voltage**<br>~~=—-—~~<br>~~a~~|**Reverse Recovery**<br>**Time (†)**<br>~~=—-—~~<br>|**Max. Average**<br>**Rectified Current (†)**<br>~~=—-—~~|**Max. Peak Forward**<br>**Surge Current (†)**<br>~~i~~|**Forward**<br>**Voltage Drop**<br>~~ee~~|**Forward**<br>**Voltage Drop**<br>~~ee~~|**Max. Reverse**<br>**Current**<br>~~ee~~|**Max. Reverse**<br>**Current**<br>~~ee~~|**Pin-out**<br>**Config.**|
|---|---|---|---|---|---|---|---|---|---|
||**VRRM**<br>~~=—-—~~<br>~~i~~<br>~~a~~|**trr**<br>~~=—-—~~<br>~~i~~<br>~~ae~~|**IO**<br>~~=—-—~~<br>~~i~~|**IFSM**<br>~~i~~<br>~~i~~<br>~~|~~|**VF @ IF**<br>~~i~~<br>~~ee~~<br>~~|~~<br>~~ee~~||**IR @ VR**<br>~~i~~<br>~~ee~~<br>~~ee~~|||
||**V**<br>~~=—-—~~<br>~~a ~~|**ns**<br>~~=—-—~~<br> ~~ae~~|**mA**<br>~~=—-—~~|**A**<br>~~i~~<br>~~|~~|**V**<br>~~ee~~<br>~~|~~|**mA**<br>~~ee~~<br>~~ee~~|µ**A**<br>~~ee~~<br>~~ee~~|**V**<br>~~ee~~||
|**200mW Switching Diodes / SOT-323**<br> ~~ae~~<br>~~|~~<br>~~ee~~||||||||||
|**BAS16W**|75|4.0|150|2.0|1.0|50|1.0|75|Fig.1|
|**BAS19W**<br>**BAS20W**<br>**BAS21W**<br>~~eee~~|120<br>200<br>250<br>~~eee~~|50<br>50<br>50<br>~~eee~~|200<br>200<br>200<br>~~eee~~|2.5<br>2.5<br>2.5<br>~~eee~~|1.0<br>1.0<br>1.0<br>~~eee~~|100<br>100<br>100<br>~~eee~~|0.1<br>0.1<br>0.1<br>~~eee~~|100<br>150<br>200<br>~~eee~~|Fig.1<br>Fig.1<br>Fig.1<br>~~eee~~|
|**BAV70W**<br>~~eee~~<br>~~Flr~~|75<br>~~eee~~<br>~~Flr~~|4.0<br>~~eee~~<br>|150<br>~~eee~~<br>|2.0<br>~~eee~~<br>|1.0<br>~~eee~~<br>|50<br>~~eee~~<br>|2.5<br>~~eee~~<br>|75<br>~~eee~~<br>|Fig.3<br>~~eee~~<br>|
|**BAV99W**<br>~~Flr~~|75<br>~~Flr~~|4.0<br>|150<br>|2.0<br>|1.0<br>|50<br>|2.5<br>|75<br>|Fig.4<br>|
|**BAW56W**<br>~~Flra~~|75<br>~~Flra~~|4.0<br>~~a~~|150<br>~~a~~|2.0<br>~~a~~|1.0<br>~~a~~|50<br>~~a~~|2.5<br>~~a~~|75<br>~~a~~|Fig.2<br>~~a~~|
|**MMBD4148W**<br>~~a~~|75<br>~~a~~|4.0<br>~~a~~|150<br>~~a~~|2.0<br>~~a~~|1.0<br>~~a~~|50<br>~~a~~|1.0<br>~~a~~|75<br>~~a~~|Fig.1<br>~~a~~|
|**MMBD4448W**<br>~~a~~<br>~~PF~~|75<br>~~a~~|4.0<br>~~a~~|250<br>~~a~~|4.0<br>~~a~~|1.0<br>~~a~~|100<br>~~a~~|2.5<br>~~a~~|75<br>~~a~~<br>~~ee~~|Fig.1<br>~~a~~<br>~~ee~~|
|**350mW Switching Diodes / SOT-23**<br>~~a~~<br>~~ee~~<br>~~ee~~<br>~~PF~~||||||||||
|**BAL99**<br>~~PF~~<br>~~hr~~<br>~~Flr~~|75<br>~~hr~~<br>~~Flr~~|4.0<br>|150<br>|2.0<br>|1.0<br>|50<br>|2.5<br>|75<br>~~ee~~<br>|Fig. 5<br>~~ee~~<br>|
|**BAW56**<br>~~PF~~<br>~~Flr~~|75<br>~~Flr~~|4.0<br>|150<br>|2.0<br>|1.0<br>|50<br>|2.5<br>|75<br>~~ee~~<br>|Fig. 2<br>~~ee~~<br>|
|**BAV70**<br>~~Flra~~|75<br>~~Flra~~|4.0<br>~~a~~|150<br>~~a~~|2.0<br>~~a~~|1.0<br>~~a~~|50<br>~~a~~|2.5<br>~~a~~|75<br>~~a~~|Fig. 3<br>~~a~~|
|**BAV99**<br>~~a~~|75<br>~~a~~|4.0<br>~~a~~|150<br>~~a~~|2.0<br>~~a~~|1.0<br>~~a~~|50<br>~~a~~|2.5<br>~~a~~|75<br>~~a~~|Fig. 4<br>~~a~~|
|**BAS16**<br>~~a~~|75<br>~~a~~|4.0<br>~~a~~|150<br>~~a~~|2.0<br>~~a~~|1.0<br>~~a~~|50<br>~~a~~|1.0<br>~~a~~|75<br>~~a~~|Fig. 1<br>~~a~~|
|**MMBD914**|75|4.0|150|2.0|1.0|50|2.5|75|Fig. 1|
|**MMBD4148**<br>~~———~~|75<br>~~———~~|4.0<br>~~———~~|150<br>~~———~~|2.0<br>~~———~~|1.0<br>~~———~~|50<br>~~———~~|2.5<br>~~———~~|75<br>~~———~~|Fig. 1<br>~~———~~|
|**MMBD4448**<br>~~———~~|75<br>~~———~~|4.0<br>~~———~~|250<br>~~———~~|4.0<br>~~———~~|1.0<br>~~———~~|100<br>~~———~~|2.5<br>~~———~~|75<br>~~———~~|Fig. 1<br>~~———~~|
|**MMBD7000**<br>~~———~~|75<br>~~———~~|4.0<br>~~———~~|150<br>~~———~~|2.0<br>~~———~~|1.25<br>~~———~~|150<br>~~———~~|1.0<br>~~———~~|50<br>~~———~~|Fig. 4<br>~~———~~|
|**BAS19***<br>**BAS20***<br>**BAS21***<br>~~———~~<br>~~ee~~|120<br>200<br>250<br>~~———~~<br>~~ee~~|50<br>50<br>50<br>~~———~~<br>~~ee~~|200<br>200<br>200<br>~~———~~<br>~~ee~~|2.5<br>2.5<br>2.5<br>~~———~~<br>~~ee~~|1.0<br>1.0<br>1.0<br>~~———~~<br>~~ee~~|100<br>100<br>100<br>~~———~~<br>~~ee~~|0.1<br>0.1<br>0.1<br>~~———~~<br>~~ee~~|100<br>150<br>200<br>~~———~~<br>~~ee~~|Fig. 1<br>Fig. 1<br>Fig. 1<br>~~———~~<br>~~ee~~|
|**BAS31**<br>~~ee~~<br>~~=~~<br>~~we~~|75<br>~~ee~~<br>~~ILI~~|4.0<br>~~ee~~<br>~~ILI~~|250<br>~~ee~~<br>~~ILIILI~~|4.0<br>~~ee~~<br>~~ILI~~|1.0<br>~~ee~~<br>~~ILI~~|100<br>~~ee~~<br>~~ILI~~|2.5<br>~~ee~~<br>~~ILI~~|75<br>~~ee~~<br>~~ILI~~<br>~~LI~~|Fig.4<br>~~ee~~<br>~~ILI~~<br>~~LI~~|
|**BAV23S***<br>~~=~~<br>~~we~~|250<br>~~ILI~~|50<br>~~ILI~~|200<br>~~ILIILI~~|3.0<br>~~ILI~~|1.0<br>~~ILI~~|100<br>~~ILI~~|0.1<br>~~ILI~~|200<br>~~ILI~~<br>~~LI~~|Fig.4<br>~~ILI~~<br>~~LI~~|
|*Power Dissipation (Pd) = 250mW<br>Figure 1, Single<br>Figure 2, Common Anode<br>Figure 3, Common Cathode<br>Figure 4, Series<br>Figure 5, Single (Alt.)<br>~~=~~<br>~~we~~<br>~~ILIILI~~<br>~~LI~~||||||||||



Figure 3, Common Cathode Figure 4, Series Figure 5, Single (Alt.) 

**(†) Reference product datasheet for specific test conditions.** 

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Updated at April 27, 2026

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