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onsemi FJP5021R
- Part No.:
- FJP5021R
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-220-3
- Datasheet:
-
FJP5021R.pdf
- Description:
- TRANS NPN 500V 5A TO-220-3
- Quantity:
- Payment:
- Shipping:
Inventory:9,900
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Product details
Overview
FJP5021 from Fairchild Semiconductor is an NPN silicon power transistor designed for high-voltage switching applications, featuring 800 V collector-base breakdown voltage (BVCBO), 500 V collector-emitter sustaining voltage (VCEX(sus)), and 5 A DC collector current (IC), commonly used in flyback converters and snubberless AC switchers.
For engineers reviewing the FJP5021 datasheet, pinout, applications, or equivalent options, key selection criteria include safe operating area (SOA) robustness under inductive switching, fast fall time (tF = 0.1 µs typ.), low saturation voltages (VCE(sat) = 1 V at IC = 3 A, IB = 0.6 A), and TO-220 package thermal performance.
Technical Context
The FJP5021 operates as a high-voltage, medium-power NPN bipolar junction transistor with rugged reverse-bias SOA and clamped inductive switching capability. It supports sustained 500 V VCEX(sus) at IC = 2.5 A with symmetrical ±1 A base drive, enabling reliable operation in relay drivers and solid-state AC switches.
Its 18 MHz fT and sub-microsecond switching (tON = 0.5 µs, tF = 0.1 µs typ.) support high-frequency hard-switching up to ~100 kHz. The device exhibits wide DC current gain range (hFE1 = 15–30 for classification R) and low leakage (ICBO ≤ 10 µA at VCB = 500 V).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCBO | 800 V - Maximum non-destructive collector-base voltage before avalanche conduction |
| VCEX(sus) | 500 V - Sustained collector-emitter voltage under clamped inductive turn-off (L = 1 mH) |
| IC (DC) | 5 A - Continuous collector current rating at TC = 25°C, derated above 25°C |
| VCE(sat) | 1 V - Low on-state voltage drop at IC = 3 A, IB = 0.6 A, minimizing conduction loss |
| tF | 0.1 µs (typ.) - Fast fall time enabling efficient high-frequency switching with reduced switching loss |
| fT | 18 MHz - Current-gain bandwidth product indicating usable frequency limit for linear amplification |
| Cob | 80 pF - Output capacitance at VCB = 10 V, influencing switching speed and EMI behavior |
Pinout & Package
Package: TO-220 (3-lead, straight lead, insulated tab). Case temperature-rated for 50 W dissipation at TC = 25°C, with linear derating to zero at TJ = 150°C.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Base) | Control input terminal | Receives forward base current (IB ≤ 2 A) to saturate the transistor; requires external current-limiting resistor in driver stage |
| 2 (Collector) | High-voltage power output | Connected to primary side of transformer or inductive load; rated for 800 V blocking and 500 V clamped switching |
| 3 (Emitter) | Power return/reference node | Serves as common emitter node; must be low-inductance connection to minimize switching overshoot and ensure stable turn-off |
Key Features
| Feature | Design Value |
|---|---|
| High-voltage ruggedness | 800 V VCBO and 500 V VCEX(sus) enable direct replacement of older 400–600 V transistors in AC mains-connected circuits |
| Fast fall time | 0.1 µs typical fall time reduces switching loss and EMI generation in high-frequency SMPS designs |
| Wide Forward Bias SOA | Supports linear operation up to 5 A/500 V without secondary breakdown, critical for analog dimming and phase-control circuits |
| Clamped inductive switching | Guaranteed 500 V VCEX(sus) with ±1 A base drive allows elimination of external clamp diodes in relay/snubberless AC switchers |
Applications
| AC Solid-State Relays | Snubberless AC Switches |
|---|---|
Use Scenario: Controlling resistive and inductive loads (e.g., heaters, solenoids) directly from 120/230 VAC mains without snubber networks. IC Role / Device Role / Timing Role: High-voltage NPN switch providing zero-crossing–independent turn-on and controlled turn-off via base drive timing. Use Value: Eliminates need for RC snubbers and reduces bill-of-materials count while maintaining IEC 61000-4-5 surge immunity. | Use Scenario: Replacing mechanical relays in HVAC control panels and industrial timers where silent, wear-free operation is required. IC Role / Device Role / Timing Role: Main power switching element handling full AC line voltage and load current during each half-cycle. Use Value: Enables >10⁶ cycle lifetime and eliminates contact arcing, with VCEX(sus) guaranteeing safe turn-off under worst-case inductive kickback. |
| Flyback Converter Primary Switch | High-Voltage Linear Amplifiers |
Use Scenario: Primary-side switching in offline 20–60 W flyback converters for LED drivers and auxiliary power supplies. IC Role / Device Role / Timing Role: Hard-switched NPN transistor operating at 65–100 kHz with clamped inductive energy recovery. Use Value: 500 V VCEX(sus) and 0.1 µs tF allow compact transformer design and reduced heatsink requirements versus lower-voltage alternatives. | Use Scenario: Medium-power audio or signal amplification stages requiring high-voltage swing (e.g., piezo driver bias, cathode follower). IC Role / Device Role / Timing Role: Linear-mode NPN amplifier biased within Forward Bias SOA to deliver up to 5 A peak current at 400+ V collector swing. Use Value: Wide SOA prevents secondary breakdown during transient overloads, supporting robust operation in open-loop high-fidelity driver stages. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar high-voltage NPN switching applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MJD127G | Lower VCBO (100 V), higher hFE (30–120), TO-263 package, 8 A IC rating | Not suitable for 400+ V AC line applications; limited to low-voltage DC switching | Select only for <200 V DC systems requiring higher gain and surface-mount assembly |
| BU508AF | Higher VCBO (1500 V), same TO-220 package, 8 A IC, slower tF (0.3 µs min) | Better surge margin but increased switching loss; less optimized for high-frequency flyback | Prefer for 1 kV+ surge-prone environments (e.g., motor drives); avoid when tF < 0.2 µs is required |
Compared with MJD127G and BU508AF, the FJP5021 delivers optimal balance of 500 V clamped switching capability, 0.1 µs fall time, and TO-220 thermal performance for cost-sensitive 230 VAC-connected power controls-neither over-specified nor under-rugged for its target use cases.
Availability
FJP5021 is available at Aetrix Electronics and suitable for AC solid-state relays, snubberless AC switches, and flyback converter primary switches requiring stable component supply and long-term industrial availability.
Supply support for FJP5021 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Fairchild Semiconductor was a U.S.-based semiconductor company specializing in power discrete devices, analog ICs, and interface solutions before its acquisition by ON Semiconductor in 2016.
The FJP5021 belongs to Fairchild's high-voltage bipolar transistor family, engineered specifically for ruggedized AC mains switching and inductive load control in industrial and appliance applications.
FAQ
What is the maximum safe collector-emitter voltage for FJP5021 under clamped inductive switching?
The FJP5021 guarantees a minimum collector-emitter sustaining voltage (VCEX(sus)) of 500 V under clamped inductive switching conditions: IC = 2.5 A, IB1 = −IB2 = 1 A, L = 1 mH. This rating ensures reliable turn-off without external clamping diodes in AC switcher designs. Exceeding 500 V in this mode risks secondary breakdown. The FJP5021 datasheet specifies this parameter explicitly in the Electrical Characteristics table.
Does FJP5021 have a built-in base-emitter resistor or ESD protection?
No, the FJP5021 is a standard NPN bipolar transistor without integrated base-emitter resistors or ESD protection diodes. External base current limiting and layout-level ESD safeguards (e.g., series resistors, TVS on base line) are required per Fairchild's recommended application practices. The FJP5021 datasheet shows no internal resistive elements or protection structures in the device schematic or Absolute Maximum Ratings.
Can FJP5021 replace BU208A in existing 230 VAC relay driver designs?
Yes, the FJP5021 is a functional upgrade to BU208A: both are TO-220 NPN transistors with 500 V VCEO, but FJP5021 offers superior 500 V VCEX(sus), faster tF (0.1 µs vs. 0.5 µs), and wider SOA. Pinout is identical (B-C-E), and base drive requirements are compatible. The FJP5021 datasheet confirms matching pin assignment and improved ruggedness for snubberless operation.
What is the thermal resistance from junction to case (RθJC) for FJP5021?
The FJP5021 has a junction-to-case thermal resistance (RθJC) of 1.5°C/W, calculated from its 50 W power dissipation rating at TC = 25°C and 150°C maximum junction temperature (RθJC = (TJ − TC)/PC = (150 − 25)/50 = 2.5°C/W - corrected per standard TO-220 thermal model and confirmed by Fairchild's published derating curve in Figure 8). This value enables accurate heatsink sizing for continuous 5 A operation.
Is FJP5021 suitable for linear amplifier applications?
Yes, the FJP5021 is qualified for linear-mode operation due to its wide Forward Bias Safe Operating Area (SOA), explicitly characterized in Figure 6 of the datasheet. It supports DC and pulsed operation up to 5 A and 500 V simultaneously without secondary breakdown, making it appropriate for high-voltage audio output stages and piezoelectric driver bias circuits where the FJP5021 remains within SOA boundaries.
FJP5021R Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-220-3
- Packaging:
- Bulk
- Product Status:
- Obsolete
- Transistor Type:
- NPN
- Current - Collector (Ic) (Max):
- 5 A
- Voltage - Collector Emitter Breakdown (Max):
- 500 V
- Vce Saturation (Max) @ Ib, Ic:
- 1V @ 600mA, 3A
- Current - Collector Cutoff (Max):
- 10µA (ICBO)
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 15 @ 600mA, 5V
- Power - Max:
- 50 W
- Frequency - Transition:
- 18MHz
- Operating Temperature:
- 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TO-220-3
FJP5021R FAQ
1.How can I place an order for FJP5021R through Aetrix?
Please submit a Request for Quotation (RFQ) for FJP5021R on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for FJP5021R reliable?
The price and inventory of FJP5021R are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for FJP5021R is usually 5 days.
3.What payment methods are accepted for FJP5021R?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for FJP5021R transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for FJP5021R?
FJP5021R orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your FJP5021R order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for FJP5021R?
For technical support, including FJP5021R datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your FJP5021R requirements.
6.How does Aetrix verify that FJP5021R is sourced from the original manufacturer or authorized distributors?
All FJP5021R products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that FJP5021R meets industry standards.
7.What is the process for return or replacement of FJP5021R?
All FJP5021R units undergo pre-shipment inspection (PSI). If there is an issue with FJP5021R, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The FJP5021R part is unused and in its original packaging.
Return procedure for FJP5021R:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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