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

onsemi MPSA12_D75Z

Name: MPSA12_D75Z
Brand: onsemi
SKU: MPSA12_D75Z
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: MPSA12_D75Z

Manufacturer:: onsemi

Category:: Single Bipolar Transistors

Package:: TO-226-3, TO-92-3 (TO-226AA) Formed Leads

Datasheet:: MPSA12_D75Z.pdf

Description:: TRANS NPN DARL 20V 1.2A TO-92-3

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Product details

Overview

MPSA12_D75Z from ON Semiconductor (formerly Fairchild) is an NPN Darlington transistor in TO-92 package, rated for 20 V V_CEO, 1.2 A continuous collector current, and 625 mW power dissipation at 25°C - designed for high-gain switching in low-voltage relay drivers and small-signal amplifier stages.

For engineers reviewing the MPSA12_D75Z datasheet, pinout, applications, or equivalent options, key selection criteria include verified DC current gain ≥20,000 at 10 mA, V_CE(sat) ≤1.0 V under matched base drive, and thermal resistance R_θJA = 200°C/W for ambient-limited PCB layouts.

Technical Context

The MPSA12_D75Z implements a two-stage monolithic NPN Darlington configuration to achieve ultra-high h_FE while maintaining single-package integration. It operates with V_BE(on) = 1.4 V at I_C = 10 mA and supports safe operation up to +150°C junction temperature.

Its absolute maximum ratings specify symmetrical 20 V breakdown across both V_CES and V_CBO, with leakage currents (I_CBO, I_CES, I_EBO) capped at 100 nA - confirming suitability for stable biasing in precision analog switches and low-power logic interfaces.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	20 V - Maximum collector-emitter voltage before breakdown; defines safe operating range in 12 V relay driver circuits.
I_C (cont.)	1.2 A - Continuous collector current rating; supports direct driving of small solenoids or LED arrays without external heat sinking.
h_FE	20,000 - DC current gain at V_CE = 5 V, I_C = 10 mA; enables microampere-level base drive for 100 mA load switching.
V_CE(sat)	1.0 V - Saturation voltage at I_C = 10 mA, I_B = 0.01 mA; ensures <10 mW conduction loss per switch event.
P_D	625 mW - Total device dissipation at 25°C; derates linearly at 5.0 mW/°C above ambient, limiting usable power in sealed enclosures.
R_θJA	200°C/W - Junction-to-ambient thermal resistance; requires ≥1 cm² copper pour for sustained 500 mA operation at 50°C ambient.

Pinout & Package

TO-92 plastic package with 3-pin inline vertical lead frame; standard through-hole mounting; body diameter 3.60 mm ±0.20 mm, overall length 14.47 mm ±0.40 mm.

Pin/Terminal	Circuit Role	Design Meaning
1 (Emitter)	Current sink terminal	Connected to ground or low-side return path; carries full load current in common-emitter configurations.
2 (Base)	Control input node	Receives low-current drive signal; 0.01 mA base current suffices to saturate 10 mA collector current.
3 (Collector)	High-side output node	Switches positive rail to load; must be isolated from shared ground when used in floating-load topologies.

Key Features

Feature	Design Value
Ultra-high DC current gain	h_FE ≥20,000 at I_C = 10 mA - reduces MCU GPIO current demand and eliminates need for pre-driver stages.
Low saturation voltage	V_CE(sat) ≤1.0 V - minimizes power loss and self-heating during extended on-time operation.
Wide junction temperature range	T_J = –55°C to +150°C - supports deployment in automotive under-hood and industrial control environments.
Low leakage performance	I_CBO/I_CES/I_EBO ≤100 nA - ensures stable off-state behavior in battery-powered sleep-mode circuits.

Applications

Relay Driver Circuits	Small-Signal Amplifiers
Use Scenario: Driving 5–12 V electromagnetic relays with coil resistances between 100 Ω and 500 Ω in PLC I/O modules. IC Role / Device Role / Timing Role: High-gain current amplifier translating 3.3 V/5 V logic signals into 50–100 mA coil current. Use Value: Eliminates need for discrete driver transistors or dedicated relay driver ICs, reducing BOM count and layout area.	Use Scenario: Building low-noise preamplifier stages for sensor signals in portable instrumentation. IC Role / Device Role / Timing Role: NPN Darlington configured as common-emitter amplifier with fixed bias network. Use Value: Delivers >60 dB voltage gain at audio frequencies while maintaining input impedance >1 MΩ due to high h_FE.
LED Array Switches	Low-Power Logic Level Shifters
Use Scenario: Switching parallel strings of indicator LEDs (e.g., status panels in HVAC controllers). IC Role / Device Role / Timing Role: Saturated switch controlling up to 100 mA total LED current from microcontroller GPIO. Use Value: Enables direct GPIO control without series current-limiting resistor redesign; V_CE(sat) keeps LED forward voltage drop predictable.	Use Scenario: Translating 3.3 V logic outputs to 5 V TTL-compatible inputs in mixed-voltage digital systems. IC Role / Device Role / Timing Role: Active pull-up stage with Darlington emitter-follower configuration. Use Value: Provides clean 5 V logic high with <1 µs propagation delay and no shoot-through risk during level transitions.

Relay Driver Circuits

Small-Signal Amplifiers

Use Scenario: Driving 5–12 V electromagnetic relays with coil resistances between 100 Ω and 500 Ω in PLC I/O modules.

IC Role / Device Role / Timing Role: High-gain current amplifier translating 3.3 V/5 V logic signals into 50–100 mA coil current.

Use Value: Eliminates need for discrete driver transistors or dedicated relay driver ICs, reducing BOM count and layout area.

Use Scenario: Building low-noise preamplifier stages for sensor signals in portable instrumentation.

IC Role / Device Role / Timing Role: NPN Darlington configured as common-emitter amplifier with fixed bias network.

Use Value: Delivers >60 dB voltage gain at audio frequencies while maintaining input impedance >1 MΩ due to high h_FE.

LED Array Switches

Low-Power Logic Level Shifters

Use Scenario: Switching parallel strings of indicator LEDs (e.g., status panels in HVAC controllers).

IC Role / Device Role / Timing Role: Saturated switch controlling up to 100 mA total LED current from microcontroller GPIO.

Use Value: Enables direct GPIO control without series current-limiting resistor redesign; V_CE(sat) keeps LED forward voltage drop predictable.

Use Scenario: Translating 3.3 V logic outputs to 5 V TTL-compatible inputs in mixed-voltage digital systems.

IC Role / Device Role / Timing Role: Active pull-up stage with Darlington emitter-follower configuration.

Use Value: Provides clean 5 V logic high with <1 µs propagation delay and no shoot-through risk during level transitions.

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN Darlington transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
MPSA13_D75Z	Same TO-92 package; higher h_FE (min. 50,000), same V_CEO/I_C ratings	Better suited for ultra-low-base-drive applications (e.g., phototransistor-coupled triggers)	Select when base drive current is constrained below 5 µA and load current remains ≤100 mA.
ULN2003A	7-channel Darlington array in SO-16; integrated clamp diodes; max 500 mA per channel	Designed for multi-load digital interfacing (e.g., stepper motor phases, printer head drivers)	Choose for multi-output systems requiring consolidated drive and protection; not a single-device replacement.

Compared with MPSA12_D75Z, MPSA13_D75Z offers higher gain at identical form factor, while ULN2003A trades single-transistor simplicity for multi-channel integration and built-in flyback protection - making each suitable for distinct system partitioning strategies.

Availability

MPSA12_D75Z is available at Aetrix Electronics and suitable for relay drivers, LED array switches, small-signal amplifiers, and low-power logic level shifters requiring stable component supply across industrial control, building automation, and consumer electronics production.

Supply support for MPSA12_D75Z 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

ON Semiconductor is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.

The MPSA12_D75Z belongs to ON Semiconductor's legacy general-purpose bipolar transistor family, engineered specifically for cost-sensitive, high-reliability discrete switching and amplification in space-constrained through-hole designs.

FAQ

What is the maximum continuous collector current rating for the MPSA12_D75Z?

The MPSA12_D75Z is rated for 1.2 A continuous collector current at T_A = 25°C. This rating assumes adequate PCB copper area for thermal dissipation; actual usable current drops to ~500 mA at 70°C ambient due to 5.0 mW/°C derating from its 625 mW P_D limit. Always verify junction temperature using R_θJA = 200°C/W in final layout.

Does the MPSA12_D75Z have integrated base-emitter resistors?

No, the MPSA12_D75Z is a bare NPN Darlington transistor with no internal base-emitter resistors. External base biasing components - such as a series current-limiting resistor - must be provided by the circuit designer to set operating point and ensure saturation. This differs from digital transistors like the NSM80012MR6T1G, which integrate built-in resistors.

Can the MPSA12_D75Z replace the MPSA14 in existing designs?

The MPSA12_D75Z and MPSA14 share identical TO-92 packaging and pinout but differ in polarity and breakdown ratings: MPSA12_D75Z is NPN with V_CEO = 20 V, while MPSA14 is PNP with V_CEO = –20 V. They are not interchangeable without circuit revision. The MPSA12_D75Z datasheet explicitly references MPSA14 for comparative characteristics only.

What is the typical V_CE(sat) of the MPSA12_D75Z under standard test conditions?

The typical V_CE(sat) of the MPSA12_D75Z is 1.0 V when tested at I_C = 10 mA and I_B = 0.01 mA. This value reflects guaranteed maximum performance under pulse conditions (≤300 µs, ≤2% duty cycle); sustained DC operation may increase saturation voltage slightly due to self-heating, especially above 50 mA load current.

Is the MPSA12_D75Z suitable for automotive under-hood applications?

Yes, the MPSA12_D75Z supports junction temperatures from –55°C to +150°C and meets automotive-grade reliability expectations for non-safety-critical functions. However, it is not AEC-Q101 qualified; for production automotive use, ON Semiconductor recommends verifying qualification status per lot and implementing additional board-level thermal and ESD protection consistent with ISO 16750 requirements.

MPSA12_D75Z Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

Package/Case:: TO-226-3, TO-92-3 (TO-226AA) Formed Leads

Packaging:: Tape & Box (TB)

Product Status:: Obsolete

Transistor Type:: NPN - Darlington

Current - Collector (Ic) (Max):: 1.2 A

Voltage - Collector Emitter Breakdown (Max):: 20 V

Vce Saturation (Max) @ Ib, Ic:: 1V @ 10µA, 10mA

Current - Collector Cutoff (Max):: 100nA

DC Current Gain (hFE) (Min) @ Ic, Vce:: 20000 @ 10mA, 5V

Power - Max:: 625 mW

Frequency - Transition:: -

Operating Temperature:: -55°C ~ 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-92-3

MPSA12_D75Z FAQ

1.How can I place an order for MPSA12_D75Z through Aetrix?

Please submit a Request for Quotation (RFQ) for MPSA12_D75Z 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 MPSA12_D75Z reliable?

The price and inventory of MPSA12_D75Z are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MPSA12_D75Z is usually 5 days.

3.What payment methods are accepted for MPSA12_D75Z?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MPSA12_D75Z transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for MPSA12_D75Z?

MPSA12_D75Z orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your MPSA12_D75Z 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 MPSA12_D75Z?

For technical support, including MPSA12_D75Z datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MPSA12_D75Z requirements.

6.How does Aetrix verify that MPSA12_D75Z is sourced from the original manufacturer or authorized distributors?

All MPSA12_D75Z 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 MPSA12_D75Z meets industry standards.

7.What is the process for return or replacement of MPSA12_D75Z?

All MPSA12_D75Z units undergo pre-shipment inspection (PSI). If there is an issue with MPSA12_D75Z, 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 MPSA12_D75Z part is unused and in its original packaging.

Return procedure for MPSA12_D75Z:

1.Submit a request within 90 days.

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

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