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Diodes Incorporated FZT958TA
- Part No.:
- FZT958TA
- Manufacturer:
- Diodes Incorporated
- Category:
- Single Bipolar Transistors
- Package:
- TO-261-4, TO-261AA
- Datasheet:
-
FZT958TA.pdf
- Description:
- TRANS PNP 400V 0.5A SOT-223-3
- Quantity:
- Payment:
- Shipping:
Inventory:6,101
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Product details
Overview
FZT958TA from Diodes Incorporated is a 400V PNP high-voltage bipolar junction transistor in SOT223 package, designed for high-voltage switching and linear regulation. It delivers -0.5A continuous collector current, -400mV VCE(sat) at -0.5A, and BVCEO = -400V, supporting applications such as flyback snubber circuits and industrial power supply hold-up stages.
For engineers reviewing the FZT958TA datasheet, FZT958TA pinout, FZT958TA application, or FZT958TA equivalent, key selection criteria include verified high-voltage blocking capability (-400V), low saturation voltage under load, thermal resistance (RθJA = 42°C/W on 52mm × 52mm 2oz Cu), and AEC-Q101 readiness for automotive-grade reliability validation.
Technical Context
This PNP transistor operates with emitter-grounded configuration and supports high-voltage DC-DC converter topologies requiring robust avalanche-rated breakdown. Its hFE ≥ 100 at -0.5A ensures stable current gain under sustained conduction, while fT = 85MHz enables moderate-speed switching in quasi-resonant and soft-switching designs.
The device features low RθJL = 8.8°C/W (junction-to-lead), enabling efficient heat transfer to PCB copper when mounted with collector lead soldered to thermal pad. ESD ratings of 4kV HBM and 400V MM confirm suitability for assembly environments with controlled static handling.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Collector-Emitter Voltage (VCEO) | -400 V - Enables use in 300–400V DC bus applications without derating. |
| Continuous Collector Current (IC) | -0.5 A - Supports sustained conduction in auxiliary power rails and bias supplies. |
| VCE(sat) @ -0.5A | < -400 mV - Minimizes conduction loss and self-heating in linear-regulator or clamping roles. |
| hFE @ -0.5A | 100–200 - Ensures predictable base drive requirements for gate-driving or current-mirror circuits. |
| Thermal Resistance (RθJA) | 42 °C/W - Validated on 52mm × 52mm 2oz Cu PCB; defines maximum ambient temperature for 3W dissipation. |
| Transition Frequency (fT) | 85 MHz - Supports switching above 100kHz with acceptable gain margin in driver stages. |
| ESD HBM Rating | 4,000 V - Meets JEDEC Class 3A; reduces risk of field failure during board handling and integration. |
Pinout & Package
Package: SOT223 (Type DN), surface-mount, 4-pin variant with collector-connected tab (pin 3) for thermal and electrical connection. Molded green compound, UL 94V-0 rated, matte tin-plated leads.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1 (Emitter) | Emitter terminal | Primary current exit path; connects to high-side rail or regulated output node. |
| Pin 2 (Base) | Control input | Receives negative base current to turn on; requires current-limiting resistor in series. |
| Pin 3 (Collector / Tab) | Collector terminal + thermal pad | Electrically and thermally connected to PCB copper; must be routed to ground or return path for heat sinking. |
| Pin 4 (Collector) | Collector terminal (redundant) | Secondary collector connection; electrically tied to pin 3; used for mechanical stability and current sharing. |
Key Features
| Feature | Design Value |
|---|---|
| High-voltage blocking | BVCEO = -400V ensures safe operation in 380V DC-link snubbers and offline SMPS clamp circuits. |
| Low saturation voltage | VCE(sat) ≤ -400mV at -0.5A reduces power loss and thermal stress in linear regulator configurations. |
| Stable gain at high current | hFE ≥ 100 up to -0.5A enables predictable base drive design without gain collapse. |
| Lead-free & halogen-free | RoHS 3 compliant, <900ppm Br/Cl, <1000ppm Sb - meets automotive and industrial environmental mandates. |
| Thermally optimized package | RθJL = 8.8°C/W allows direct heat transfer from junction to PCB via collector tab. |
Applications
| Industrial Power Supply Hold-Up | Automotive HVAC Blower Control |
|---|---|
Use Scenario: Maintains auxiliary 12V rail during main DC-DC converter startup or brownout in industrial PLC power modules. IC Role / Device Role / Timing Role: PNP pass transistor configured as active hold-up switch, activated by undervoltage detection circuitry. Use Value: -400V rating prevents breakdown during transient overvoltage on 300V intermediate bus; -400mV VCE(sat) limits hold-up stage power loss to <200mW at 0.5A. |
Use Scenario: Controls high-side current to brushed DC blower motor in vehicle cabin climate systems. IC Role / Device Role / Timing Role: High-voltage PNP switch driving motor phase through external flyback diode and RC snubber. Use Value: -400V VCEO withstands inductive kickback up to 350V; AEC-Q101 qualification path supports automotive change control and PPAP documentation. |
| AC-DC Adapter Snubber | LED Driver Overvoltage Clamp |
Use Scenario: Absorbs leakage inductance energy in flyback transformer primary during MOSFET turn-off in universal-input AC-DC adapters. IC Role / Device Role / Timing Role: Active clamp transistor triggered by auxiliary winding voltage sensing, operating in linear region. Use Value: Low VCE(sat) minimizes clamp conduction loss; high BVCEO eliminates need for series Zener stacking in 230VAC designs. |
Use Scenario: Protects constant-current LED string drivers from overvoltage transients caused by open-circuit faults or lightning surges. IC Role / Device Role / Timing Role: Crowbar device placed across output, triggered by overvoltage comparator to short output and shut down controller. Use Value: -1.5A ICM handles surge currents up to 10ms; -7V VEBO ensures reliable triggering from dedicated Zener reference network. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP high-voltage transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ZTX958 | BVCEO = -400V, but hFE min = 60 at -0.5A; RθJA = 60°C/W (SOT89); no AEC-Q101 path. | Limited to non-automotive, lower-power (<1.5W) linear regulation due to higher thermal resistance and lower gain. | Select if cost-sensitive and thermal budget allows >10°C/W penalty; avoid where gain stability at 0.5A is critical. |
| MJD44H11T4G | BVCEO = -80V only; IC = -8A; TO-220 package; hFE = 30–120 at -4A. | Suitable for high-current, low-voltage motor drives but cannot replace FZT958TA in >300V applications. | Use only in 24–48V systems requiring >1A; not a functional substitute for 400V blocking requirement. |
Compared with ZTX958 and MJD44H11T4G, FZT958TA uniquely balances 400V blocking, 0.5A continuous current, and SOT223 thermal performance-making it irreplaceable in space-constrained, high-voltage hold-up and snubber roles where both voltage rating and package efficiency are simultaneously critical.
Availability
FZT958TA is available at Aetrix Electronics and suitable for industrial power supply hold-up, automotive HVAC blower control, AC-DC adapter snubbing, and LED driver overvoltage clamping requiring stable component supply and long-term BOM continuity.
Supply support for FZT958TA 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
Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.
FZT958TA belongs to Diodes' high-voltage bipolar transistor product line, engineered specifically for ruggedized power management in industrial and automotive subsystems where voltage resilience, thermal efficiency, and regulatory compliance are mandatory.
FAQ
What is the maximum allowable case temperature for continuous operation?
The FZT958TA has an operating junction temperature range of -55°C to +150°C. With RθJA = 42°C/W on 52mm × 52mm 2oz Cu, the maximum case temperature at 3W dissipation is approximately +120°C ambient. Derating begins above +25°C ambient per the 24mW/°C linear factor specified in the datasheet.
Can FZT958TA be used in avalanche mode?
Yes-the device is rated for BVCEO = -400V and exhibits controlled avalanche behavior per Diodes' characterization. However, datasheet does not specify single-pulse avalanche energy (EAS). For repetitive avalanche applications, thermal limits and safe operating area curves must be strictly observed, and layout must minimize inductance in collector path.
Is the SOT223 pinout compatible with standard SOT223 footprints?
Yes-FZT958TA uses standard SOT223 (Type DN) mechanical dimensions and pin assignment: Pin 1 = Emitter, Pin 2 = Base, Pin 3 = Collector/Tab, Pin 4 = Collector. The recommended pad layout matches IPC-7351B SOIC-4 variant with thermal relief for the collector tab, confirmed in Diodes' packaging documentation.
Does FZT958TA meet AEC-Q101 requirements?
FZT958TA is manufactured in IATF 16949-certified facilities and supports PPAP documentation. While not pre-qualified as AEC-Q101, Diodes states it is "for automotive applications requiring specific change control" and offers qualification support upon request-enabling customer-led AEC-Q101 testing with full data package and process traceability.
FZT958TA Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- TO-261-4, TO-261AA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Transistor Type:
- PNP
- Current - Collector (Ic) (Max):
- 500 mA
- Voltage - Collector Emitter Breakdown (Max):
- 400 V
- Vce Saturation (Max) @ Ib, Ic:
- 240mV @ 300mA, 1A
- Current - Collector Cutoff (Max):
- 50nA (ICBO)
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 100 @ 500mA, 10V
- Power - Max:
- 3 W
- Frequency - Transition:
- 85MHz
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-223-3
FZT958TA FAQ
1.How can I place an order for FZT958TA through Aetrix?
Please submit a Request for Quotation (RFQ) for FZT958TA 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 FZT958TA reliable?
The price and inventory of FZT958TA are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for FZT958TA is usually 5 days.
3.What payment methods are accepted for FZT958TA?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for FZT958TA transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for FZT958TA?
FZT958TA orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your FZT958TA 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 FZT958TA?
For technical support, including FZT958TA datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your FZT958TA requirements.
6.How does Aetrix verify that FZT958TA is sourced from the original manufacturer or authorized distributors?
All FZT958TA 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 FZT958TA meets industry standards.
7.What is the process for return or replacement of FZT958TA?
All FZT958TA units undergo pre-shipment inspection (PSI). If there is an issue with FZT958TA, 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 FZT958TA part is unused and in its original packaging.
Return procedure for FZT958TA:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
FZT958TA Tags
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