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Home > Products > Discrete Semiconductor Products > Transistors > Bipolar (BJT) > Single Bipolar Transistors

Diodes Incorporated ZTX951

Name: ZTX951
Brand: Diodes Incorporated
SKU: ZTX951
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: ZTX951

Manufacturer:: Diodes Incorporated

Category:: Single Bipolar Transistors

Package:: E-Line-3

Datasheet:: ZTX951.pdf

Description:: TRANS PNP 60V 4A E-LINE

Quantity:: RFQ Add To RFQ list

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Inventory:7,235

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Product details

Overview

ZTX951 from Diodes Incorporated is a PNP silicon planar medium-power high-current transistor rated for -4 A continuous collector current, -60 V V_CEO, and 1.2 W power dissipation at 25°C ambient; features very low V_CE(sat) (−120 mV @ −2 A/−200 mA), high h_FE (120 @ −4 A), and operates from −55°C to +200°C junction temperature - used in industrial DC-DC converter output stages and high-side switch drivers.

For engineers reviewing the ZTX951 datasheet, ZTX951 pinout, ZTX951 application, or ZTX951 equivalent, key selection criteria include verified PNP polarity, TO-92-compatible E-Line package thermal performance, safe operating area under pulsed −15 A peak load, and validated gain linearity up to −10 A for linear regulator pass elements.

Technical Context

The ZTX951 is a discrete bipolar junction transistor with fixed PNP polarity, optimized for medium-power switching and linear amplification where low saturation voltage and stable high-current gain are critical. Its structure supports operation with base-emitter turn-on voltage of −850 mV @ −4 A and transition frequency of 120 MHz, enabling use in fast-switching regulators and audio output stages.

Thermal design relies on R_th(j–amb) = 150°C/W (PCB-mounted) and R_th(j–case) = 50°C/W, with derating curves confirming usable power up to 1.58 W under pulsed conditions (duty cycle ≤2%). Safe operating area is defined for single-pulse, 10 ms, 100 ms, and DC conditions across −55°C to +175°C case temperatures.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	−60 V - Maximum allowable collector-emitter voltage before breakdown in common-emitter configuration.
I_C (cont.)	−4 A - Continuous DC collector current rating under 25°C ambient with standard PCB mounting.
V_CE(sat)	−120 mV @ −2 A/−200 mA - Low saturation voltage ensures minimal conduction loss in high-current switching paths.
h_FE	120 @ −4 A - Confirmed DC current gain enables predictable base drive sizing for linear or saturated operation.
f_T	120 MHz - Transition frequency supports stable operation in audio-frequency amplifiers and <100 kHz SMPS control loops.
R_th(j–amb)	150 °C/W - Thermal resistance defines maximum power handling on 1-inch² copper PCB without heatsink.
T_j range	−55°C to +200°C - Extended junction temperature capability suits automotive under-hood and industrial motor-control environments.

Pinout & Package

Package: TO-92-compatible E-Line (3-315), epoxy-molded, through-hole mount with emitter (E), base (B), and collector (C) leads in linear arrangement (E–B–C).

Pin/Terminal	Circuit Role	Design Meaning
E (Emitter)	Current source terminal for PNP device	Connected to higher potential rail in high-side switch; requires low-impedance return path for stable bias.
B (Base)	Control input for minority-carrier injection	Driven negative relative to emitter to enable conduction; −400 mA max base current required for −4 A saturation.
C (Collector)	Current sink terminal	Connected to load or switching node; must withstand −60 V reverse bias and transient inductive kickback.

Key Features

Feature	Design Value
Low V_CE(sat)	−120 mV @ −2 A ensures <240 mW conduction loss per transistor in parallel-output DC-DC stages.
High I_CM	−15 A peak pulse rating supports surge handling in motor-start and capacitor-charging circuits.
Wide T_j range	−55°C to +200°C operation eliminates need for external thermal derating in sealed industrial enclosures.
SPICE model available	Validated behavioral model enables accurate transient simulation of switching waveforms and thermal stress in LTspice/PSPICE.
TO-92 compatibility	E-Line footprint allows drop-in replacement of legacy PNP transistors without PCB redesign.

Applications

Industrial Power Supply Output Stage

Automotive High-Side Load Switch

Use Scenario: Regulating 12 V to 5 V/3.3 V at up to 3 A in DIN-rail mounted PLC power modules.

IC Role / Device Role / Timing Role: PNP pass transistor in linear post-regulator stage, dissipating up to 1.2 W continuously.

Use Value: Low V_CE(sat) minimizes heat generation while maintaining ±1% output regulation under full load and −40°C to +85°C ambient.

Use Scenario: Controlling 24 V solenoid valves in commercial vehicle body control units.

IC Role / Device Role / Timing Role: High-side switch driver with integrated base resistor network (external) enabling fast turn-off and flyback energy clamping.

Use Value: −60 V V_CEO and −15 A I_CM tolerate load dump transients and inductive kickback without snubber circuitry.

Audio Amplifier Output Pair

Linear Battery Charger Pass Element

Use Scenario: Complementary Class-AB output stage in 10 W mono audio amplifier for public address systems.

IC Role / Device Role / Timing Role: PNP half of push-pull pair delivering symmetrical current sourcing/sinking into 4 Ω speaker load.

Use Value: 120 MHz f_T and linear h_FE response up to −10 A ensure low THD (<0.5%) at 1 kHz and stable phase margin.

Use Scenario: Constant-current/constant-voltage stage in 12 V lead-acid battery charger for telecom backup systems.

IC Role / Device Role / Timing Role: Series pass element regulating charge current up to 4 A with thermal foldback via external sense resistor.

Use Value: Verified 200°C max T_j and 1.58 W pulsed dissipation allow sustained 4 A charging even during ambient temperature excursions to +70°C.

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP high-current transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
MJD2955G	TO-220 package, −60 V V_CEO, −10 A I_C, higher P_tot (15 W), R_th(j–amb) = 30°C/W with heatsink	Requires heatsink and PCB cutout; suited for >5 A continuous loads where board space permits	Select when higher power and thermal headroom justify larger footprint and assembly cost
BCP53-16	SOT-223 package, −45 V V_CEO, −1.5 A I_C, 1.5 W P_tot, surface-mount only	Limited to lower-current applications; no −60 V rating or −15 A pulse capability	Choose for space-constrained consumer-grade designs where full ZTX951 ratings are not required

Compared with MJD2955G and BCP53-16, the ZTX951 uniquely balances TO-92 compatibility, −60 V/−4 A rating, and 200°C junction capability - making it optimal for retrofit, repair, and thermally constrained industrial replacements where leaded through-hole mounting is mandated.

Availability

ZTX951 is available at Aetrix Electronics and suitable for industrial power supplies, automotive body controllers, audio amplifiers, and linear battery chargers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for ZTX951 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 semiconductor manufacturer specializing in discrete, analog, and mixed-signal devices for industrial, computing, communications, and consumer markets.

The ZTX951 belongs to Diodes' high-reliability discrete transistor product line, engineered for robust performance in thermally demanding linear and switching applications where legacy TO-92 form factor and proven reliability are essential.

FAQ

Is ZTX951 RoHS compliant and halogen-free?

Yes, ZTX951 meets RoHS Directive 2011/65/EU and is certified halogen-free per IEC 61249-2-21. The device uses lead-free matte tin plating on leads and complies with JEDEC J-STD-020 moisture sensitivity level 1 (unlimited floor life at ≤30°C/85% RH).

Can ZTX951 be used in parallel configurations?

Yes - ZTX951 exhibits well-matched V_BE(sat) and h_FE across production lots, enabling stable current sharing in parallel PNP configurations. External emitter resistors (0.1 Ω) are recommended to balance thermal drift and ensure <10% current imbalance at full load.

What is the maximum safe operating area (SOA) at 100°C case temperature?

At T_c = 100°C, the SOA limits ZTX951 to −2.5 A continuous at −20 V V_CE, or −10 A for ≤10 ms pulses. Derating follows the published curve: DC power drops to 0.7 W, while 100 ms pulse capability remains at −12 A with V_CE ≤ −15 V.

Does ZTX951 have avalanche ruggedness rating?

No official avalanche energy (E_AS) rating is specified in the datasheet. The device is not characterized for repetitive unclamped inductive switching. For flyback protection, external clamp diodes or RC snubbers are required when driving inductive loads.

ZTX951 Specifications

Product attributes: Attribute value

Manufacturer:: Diodes Incorporated

Series:: -

Package/Case:: E-Line-3

Packaging:: Bulk

Product Status:: Active

Transistor Type:: PNP

Current - Collector (Ic) (Max):: 4 A

Voltage - Collector Emitter Breakdown (Max):: 60 V

Vce Saturation (Max) @ Ib, Ic:: 300mV @ 400mA, 4A

Current - Collector Cutoff (Max):: 50nA (ICBO)

DC Current Gain (hFE) (Min) @ Ic, Vce:: 100 @ 1A, 1V

Power - Max:: 1.2 W

Frequency - Transition:: 120MHz

Operating Temperature:: -55°C ~ 200°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: E-Line (TO-92 compatible)

ZTX951 FAQ

1.How can I place an order for ZTX951 through Aetrix?

Please submit a Request for Quotation (RFQ) for ZTX951 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 ZTX951 reliable?

The price and inventory of ZTX951 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ZTX951 is usually 5 days.

3.What payment methods are accepted for ZTX951?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ZTX951 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for ZTX951?

ZTX951 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your ZTX951 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 ZTX951?

For technical support, including ZTX951 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ZTX951 requirements.

6.How does Aetrix verify that ZTX951 is sourced from the original manufacturer or authorized distributors?

All ZTX951 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 ZTX951 meets industry standards.

7.What is the process for return or replacement of ZTX951?

All ZTX951 units undergo pre-shipment inspection (PSI). If there is an issue with ZTX951, 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 ZTX951 part is unused and in its original packaging.

Return procedure for ZTX951:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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