| PartNumber | MJE520 | MJE521 | MJE521G |
| Description | Bipolar Transistors - BJT 30Vcbo 30Vceo 4.0Vebo 3.0A 25W | Bipolar Transistors - BJT 40Vcbo 40Vceo 4.0Vebo 4.0A 40W | Bipolar Transistors - BJT 4A 40V 40W NPN |
| Manufacturer | Central Semiconductor | Central Semiconductor | ON Semiconductor |
| Product Category | Bipolar Transistors - BJT | Bipolar Transistors - BJT | Bipolar Transistors - BJT |
| RoHS | Y | Y | Y |
| Technology | Si | Si | - |
| Mounting Style | Through Hole | Through Hole | Through Hole |
| Package / Case | TO-126-3 | TO-126-3 | TO-225-3 |
| Transistor Polarity | NPN | NPN | NPN |
| Configuration | Single | Single | Single |
| Collector Emitter Voltage VCEO Max | 30 V | 40 V | 40 V |
| Collector Base Voltage VCBO | 30 V | 40 V | 40 V |
| Emitter Base Voltage VEBO | 4 V | 4 V | 4 V |
| Maximum DC Collector Current | 7 A | 8 A | 4 A |
| Minimum Operating Temperature | - 65 C | - 65 C | - 65 C |
| Maximum Operating Temperature | + 150 C | + 150 C | + 150 C |
| Series | MJE520 | MJE521 | - |
| Packaging | Bulk | Bulk | Bulk |
| Brand | Central Semiconductor | Central Semiconductor | ON Semiconductor |
| Continuous Collector Current | 3 A | 4 A | 4 A |
| DC Collector/Base Gain hfe Min | 25 at 1 A, 1 V | 40 at 1 A, 1 V | 40 |
| Pd Power Dissipation | 25 W | 40 W | 40 W |
| Product Type | BJTs - Bipolar Transistors | BJTs - Bipolar Transistors | BJTs - Bipolar Transistors |
| Factory Pack Quantity | 1000 | 1000 | 500 |
| Subcategory | Transistors | Transistors | Transistors |
| Part # Aliases | MJE520 PBFREE | MJE521 PBFREE | - |
| Height | - | - | 11.04 mm (Max) |
| Length | - | - | 7.74 mm (Max) |
| Width | - | - | 2.66 mm (Max) |
| Unit Weight | - | - | 0.068784 oz |