My Inquiry
My Account
onsemi FJP5021OTU
- Part No.:
- FJP5021OTU
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-220-3
- Datasheet:
-
FJP5021OTU.pdf
- Description:
- TRANS NPN 500V 5A TO-220-3
- Quantity:
- Payment:
- Shipping:
Inventory:2,747
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
FJP5021OTU from Fairchild Semiconductor is an NPN silicon power transistor designed for high-voltage switching applications, featuring 500 V VCEO, 5 A continuous collector current, and 50 W power dissipation at TC = 25°C; it is commonly used in flyback converters, motor control snubbers, and industrial relay drivers.
For engineers reviewing the FJP5021OTU datasheet, pinout, applications, or equivalent options, key selection criteria include its 500 V sustaining voltage under clamped inductive switching, 0.1 µs typical fall time, and TO-220 package thermal performance for medium-power hard-switching circuits.
Technical Context
The FJP5021OTU operates as a single NPN bipolar junction transistor with base-controlled current amplification and fast switching capability. Its design supports high-voltage DC-DC conversion where robust safe operating area (SOA) and low saturation voltages are required.
It delivers 18 MHz current-gain bandwidth product at VCE = 10 V and IC = 0.6 A, and sustains 500 V in clamped inductive turn-off (VCEX(sus)) with IC = 2.5 A and symmetrical ±1 A base drive - confirming suitability for snubberless inductive load switching.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 500 V - maximum collector-emitter voltage before breakdown under open-base condition; defines upper limit for off-state blocking in switch-mode topologies. |
| IC (DC) | 5 A - continuous collector current rating; sets steady-state conduction capacity for power stage designs. |
| PC @ TC=25°C | 50 W - maximum power dissipation at case temperature of 25°C; requires heatsinking for operation above ambient. |
| tF (Typ.) | 0.1 µs - typical fall time under specified test conditions; enables high-frequency switching up to ~1 MHz with controlled loss. |
| hFE1 @ IC=0.6A | 15–50 - DC current gain range across hFE classification bins (R/O/Y); impacts base drive sizing and saturation margin. |
| Cob | 80 pF - output capacitance at VCB = 10 V; influences switching loss and EMI behavior during turn-off transitions. |
| fT | 18 MHz - current-gain bandwidth product; indicates usable frequency range for small-signal amplification or linear operation. |
Pinout & Package
Package: TO-220 (3-lead, straight lead, insulated tab). Dimensions conform to JEDEC TO-220AB standard; mounting hole Ø3.60 mm; thermal resistance RθJC ≈ 1.5°C/W (typical, with proper heatsink interface).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Base) | Control electrode | Receives forward base current to saturate the transistor; requires ≥0.6 A drive for full 3 A collector conduction per datasheet test condition. |
| 2 (Collector) | High-side current path | Connected to high-voltage rail or inductive load; carries full switched current and must be routed with clearance for 500 V isolation. |
| 3 (Emitter) | Reference node / current return | Serves as common emitter reference; connects to ground or low-side switch node; carries same current as collector in active mode. |
Key Features
| Feature | Design Value |
|---|---|
| Clamped inductive SOA | Rated for 500 V VCEX(sus) with 2.5 A collector current and ±1 A base drive - enables reliable snubberless switching in relay and solenoid drivers. |
| Fast fall time | 0.1 µs typical tF reduces switching loss and improves efficiency in 100–500 kHz power converters. |
| Wide Forward Bias SOA | Supports simultaneous high voltage and high current operation up to 500 V × 5 A boundary - critical for overvoltage-tolerant line-switching stages. |
| High hFE consistency | Three hFE bins (R/O/Y) ensure predictable base drive requirements across production lots for stable manufacturing yield. |
Applications
| Switch-Mode Power Supply (SMPS) Flyback Primary Switch | Industrial AC Motor Starter Snubber |
|---|---|
Use Scenario: Used as main switching element in 20–100 W offline flyback converters with universal AC input. IC Role / Device Role / Timing Role: NPN power switch controlling energy transfer from primary to secondary via transformer; driven by PWM controller through base resistor network. Use Value: 500 V VCEO and clamped 500 V VCEX(sus) eliminate need for external RCD snubber in many designs, reducing component count and board space. | Use Scenario: Placed across contactor coil or motor winding to suppress inductive kick during de-energization. IC Role / Device Role / Timing Role: Active clamp transistor absorbing stored magnetic energy; triggered synchronously with contact opening via auxiliary driver circuit. Use Value: 0.1 µs tF and wide reverse-bias SOA allow rapid energy dissipation without secondary breakdown, extending contactor life. |
| DC-DC Boost Converter High-Side Switch | Programmable Load Switch for 24–48 V Industrial Systems |
Use Scenario: High-side switch in isolated boost stages feeding battery charging or PoE midspan circuits. IC Role / Device Role / Timing Role: NPN configured in common-emitter topology; collector tied to input rail, emitter to inductor; base driven by level-shifted signal. Use Value: 5 A IC and 50 W PC support sustained 40–60 V, 3–4 A boost operation with forced-air cooling. | Use Scenario: Controlled power enable for PLC I/O modules, sensor transmitters, or fieldbus nodes operating from 24–48 V rails. IC Role / Device Role / Timing Role: Discrete high-side switch replacing integrated load switches; base driven by microcontroller GPIO through current-limiting resistor. Use Value: 7 V VEBO and 1.5 V VBE(sat) ensure reliable turn-on with 3.3 V or 5 V logic, while 500 V rating provides surge immunity against load dump events. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar NPN high-voltage switching transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MJD122G | Lower VCEO (100 V), higher hFE (30–240), TO-252 package; no clamped SOA rating. | Not suitable for >200 V inductive switching; limited to low-voltage DC-DC or linear regulator pass devices. | Select only for <100 V, high-gain, surface-mount applications where thermal mass is constrained. |
| BU508A | Higher VCEO (1500 V), lower fT (1 MHz), TO-3P package; similar clamped SOA but slower switching. | Better for line-frequency rectifier protection or CRT horizontal deflection; less efficient above 50 kHz. | Prefer for ultra-high-voltage, low-frequency (<20 kHz), high-reliability legacy systems requiring proven field history. |
Compared with MJD122G and BU508A, the FJP5021OTU occupies a mid-range niche: it offers superior switching speed and verified clamped SOA versus BU508A, while providing higher voltage capability and ruggedness than MJD122G - making it optimal for 20–500 kHz, 200–500 V industrial switching.
Availability
FJP5021OTU is available at Aetrix Electronics and suitable for industrial motor controls, offline SMPS designs, and programmable DC load switching requiring stable component supply and long-term manufacturability.
Supply support for FJP5021OTU 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 and analog ICs, acquired by ON Semiconductor in 2016; its legacy products remain widely deployed in industrial and automotive systems.
The FJP5021OTU belongs to Fairchild's high-voltage NPN transistor family, engineered specifically for ruggedized switching in industrial power supplies, motor drives, and electromagnetic actuator interfaces where reliability under transient stress is critical.
FAQ
What is the maximum safe operating voltage for FJP5021OTU in inductive switching?
The FJP5021OTU is rated for 500 V collector-emitter sustaining voltage (VCEX(sus)) under clamped inductive switching with IC = 2.5 A and symmetrical ±1 A base drive. This value-verified in the datasheet under L = 1 mH, VCC = 200 V conditions-is the maximum recommended repetitive voltage during turn-off. Exceeding 500 V risks secondary breakdown even with clamping, so derating to 400 V is advised for long-term reliability in production designs using FJP5021OTU.
Does FJP5021OTU have a built-in base-emitter resistor?
No, the FJP5021OTU is a standard three-terminal NPN bipolar transistor with no internal base-emitter resistor. It requires external base drive circuitry-including current-limiting resistors and, optionally, a base-emitter shunt resistor for improved turn-off speed. The datasheet specifies base current (IB) up to 2 A and recommends IB = 0.6 A for 3 A collector saturation, confirming discrete base control is mandatory for FJP5021OTU operation.
What is the thermal resistance junction-to-case for FJP5021OTU?
The FJP5021OTU has a typical junction-to-case thermal resistance (RθJC) of 1.5°C/W when mounted on a standard TO-220 heatsink with thermal compound. This value is derived from its 50 W power dissipation rating at TC = 25°C and maximum junction temperature of 150°C. Actual RθJC may vary ±15% depending on mounting pressure and interface quality; system-level thermal design must account for additional RθCS and RθSA to ensure FJP5021OTU junction temperature remains below 150°C under worst-case load.
Can FJP5021OTU replace BU208A in existing designs?
FJP5021OTU is not a direct replacement for BU208A due to differences in pinout (BU208A uses Base–Emitter–Collector order; FJP5021OTU is Base–Collector–Emitter), gain profile, and SOA characterization. While both are 500 V NPN transistors, BU208A has lower hFE (10–30) and no published clamped VCEX(sus). Swapping requires PCB layout revision and revalidation of base drive and thermal margins. FJP5021OTU should only replace BU208A after full functional and stress testing confirms compatibility in the target FJP5021OTU application.
Is FJP5021OTU RoHS compliant?
The FJP5021OTU was originally released in 2003 under pre-RoHS manufacturing standards. Fairchild did not issue a formal RoHS-compliant version of this part; later ON Semiconductor documentation lists it as "legacy, non-RoHS" with leaded terminations. For new designs requiring RoHS compliance, consider modern alternatives such as the NSS12201LT1G (SOT-23, 100 V) or MJD127 (TO-252, 100 V), or consult Aetrix Electronics for verified drop-in replacements with full RoHS/REACH certification supporting FJP5021OTU's voltage and current requirements.
FJP5021OTU Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-220-3
- Packaging:
- Tube
- 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:
- 20 @ 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
FJP5021OTU FAQ
1.How can I place an order for FJP5021OTU through Aetrix?
Please submit a Request for Quotation (RFQ) for FJP5021OTU 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 FJP5021OTU reliable?
The price and inventory of FJP5021OTU are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for FJP5021OTU is usually 5 days.
3.What payment methods are accepted for FJP5021OTU?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for FJP5021OTU transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for FJP5021OTU?
FJP5021OTU orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your FJP5021OTU 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 FJP5021OTU?
For technical support, including FJP5021OTU datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your FJP5021OTU requirements.
6.How does Aetrix verify that FJP5021OTU is sourced from the original manufacturer or authorized distributors?
All FJP5021OTU 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 FJP5021OTU meets industry standards.
7.What is the process for return or replacement of FJP5021OTU?
All FJP5021OTU units undergo pre-shipment inspection (PSI). If there is an issue with FJP5021OTU, 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 FJP5021OTU part is unused and in its original packaging.
Return procedure for FJP5021OTU:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
FJP5021OTU Tags
-
MMBT3906LT1G
onsemi
-
MMBT3904-7-F
Diodes Incorporated
-
MMBT3904LT1G
onsemi
-
MMBT3906-7-F
Diodes Incorporated
-
MMBT3904-TP
Micro Commercial Co
-
MMBT2222A-7-F
Diodes Incorporated
-
BC846BLT1G
onsemi
-
BC847B,215
Nexperia USA Inc.
-
SMMBT3904LT1G
onsemi
-
MMBT2222A-TP
Micro Commercial Co
-
MMBTA06LT1G
onsemi
-
MMBT2222ALT1G
onsemi
Tech Hub
Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
