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

onsemi 2SA2127-AE

Name: 2SA2127-AE
Brand: onsemi
SKU: 2SA2127-AE
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: 2SA2127-AE

Manufacturer:: onsemi

Category:: Single Bipolar Transistors

Package:: TO-226-3, TO-92-3 Long Body, Formed Leads

Datasheet:: 2SA2127-AE.pdf

Description:: TRANS PNP 50V 2A 3-MP

Quantity:: RFQ Add To RFQ list

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Product details

Overview

2SA2127-AE from onsemi is a PNP bipolar junction transistor (BJT) rated for -50 V V_CEO, -2 A continuous collector current, and low -0.4 V typical V_CE(sat) at -1 A / -50 mA drive-designed for high-efficiency switching in voltage regulators and relay drivers.

For engineers reviewing the 2SA2127-AE datasheet, pinout, applications, or equivalent options, key selection criteria include verified V_CE(sat) ≤ -0.4 V, h_FE ≥ 200 at -100 mA, f_T = 420 MHz, TO-92-compatible MP package, and guaranteed -50 V breakdown ratings.

Technical Context

This device uses onsemi's MBIT process to achieve low saturation voltage and wide Safe Operating Area (ASO), enabling robust pulsed operation up to I_CP = -4 A with t_stg = 250 ns and t_f = 24 ns.

It operates with V_BE(sat) = -0.9 to -1.2 V at -1 A / -50 mA, supports DC gain of h_FE1 = 200–560 (at -100 mA) and h_FE2 = 40 (at -1.5 A), and maintains Cob = 16 pF at -10 V V_CB, making it suitable for medium-speed switching with minimal capacitive loading.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	-50 V - Ensures safe operation in 48 V rail and industrial control circuits with margin against transients.
I_C (cont.)	-2 A - Supports continuous load switching for relays, lamps, and solenoids without heatsinking below 75°C ambient.
V_CE(sat)	-0.2 to -0.4 V @ -1 A / -50 mA - Reduces conduction loss to ≤ 400 mW, critical for thermally constrained designs.
f_T	420 MHz - Enables stable operation in pulse-width modulated (PWM) drivers up to ~100 kHz with low phase lag.
h_FE	200–560 @ -100 mA; 40 @ -1.5 A - Provides predictable base drive requirements across linear and saturated regions.
C_ob	16 pF @ -10 V - Limits Miller effect in switching nodes, supporting clean turn-off in inductive loads.
P_C	1 W @ T_a = 25°C - Defines thermal derating curve (PC vs. Ta) for PCB layout and enclosure airflow planning.

Pinout & Package

2SA2127-AE is housed in the MP package-a JEITA/JEDEC-standardized variant of TO-92 (1-WATT, TO-226AE), with 0.578 g mass and through-hole mounting compatibility.

Pin/Terminal	Circuit Role	Design Meaning
1	Emitter	Current sink node; connects to system ground or negative rail in high-side switch configurations.
2	Collector	Main output terminal; ties to load (e.g., relay coil anode or lamp cathode) in common-emitter switching.
3	Base	Control input; requires ≥ -50 mA drive for full saturation at -1 A, with V_BE(sat) ≤ -1.2 V.

Key Features

Feature	Design Value
MBIT process technology	Enables low V_CE(sat) and high ASO without trade-off in switching speed or leakage.
Wide Safe Operating Area (ASO)	Supports -4 A pulsed current with t_p ≤ 100 μs, preventing second breakdown during inductive kickback.
High f_T bandwidth	420 MHz gain-bandwidth ensures minimal gain roll-off in feedback-controlled linear regulators.
Low cutoff leakage	I_CBO ≤ -1 μA @ -40 V confirms stable off-state behavior in battery-backed or low-power hold circuits.

Applications

Relay Drivers	Voltage Regulators
Use Scenario: Driving 12 V/24 V electromagnetic relays in PLC I/O modules with 100% duty cycle. IC Role / Device Role / Timing Role: High-current PNP switch sinking relay coil current to ground. Use Value: V_CE(sat) ≤ -0.4 V limits power dissipation to < 400 mW, eliminating need for heatsink at 2 A load.	Use Scenario: Pass transistor in adjustable negative LDO regulators (e.g., -5 V to -15 V outputs). IC Role / Device Role / Timing Role: Series pass element controlling output voltage via base bias network. Use Value: h_FE ≥ 200 at low I_C enables precise current mirror-based error amplification.
Lamp Drivers	Industrial Control Logic
Use Scenario: Switching incandescent or LED indicator lamps in HMI panels with surge-tolerant turn-on. IC Role / Device Role / Timing Role: Low-side load switch managing steady-state and inrush current. Use Value: Wide ASO and -4 A pulse rating absorb lamp cold-resistance surges without failure.	Use Scenario: Level-shifting and signal inversion in 5 V/3.3 V mixed-voltage industrial sensor interfaces. IC Role / Device Role / Timing Role: Digital inverter or level translator with rail-to-rail swing capability. Use Value: Fast t_on/t_f (35 ns / 24 ns) supports >10 MHz digital signaling in deterministic control loops.

Relay Drivers

Voltage Regulators

Use Scenario: Driving 12 V/24 V electromagnetic relays in PLC I/O modules with 100% duty cycle.

IC Role / Device Role / Timing Role: High-current PNP switch sinking relay coil current to ground.

Use Value: V_CE(sat) ≤ -0.4 V limits power dissipation to < 400 mW, eliminating need for heatsink at 2 A load.

Use Scenario: Pass transistor in adjustable negative LDO regulators (e.g., -5 V to -15 V outputs).

IC Role / Device Role / Timing Role: Series pass element controlling output voltage via base bias network.

Use Value: h_FE ≥ 200 at low I_C enables precise current mirror-based error amplification.

Lamp Drivers

Industrial Control Logic

Use Scenario: Switching incandescent or LED indicator lamps in HMI panels with surge-tolerant turn-on.

IC Role / Device Role / Timing Role: Low-side load switch managing steady-state and inrush current.

Use Value: Wide ASO and -4 A pulse rating absorb lamp cold-resistance surges without failure.

Use Scenario: Level-shifting and signal inversion in 5 V/3.3 V mixed-voltage industrial sensor interfaces.

IC Role / Device Role / Timing Role: Digital inverter or level translator with rail-to-rail swing capability.

Use Value: Fast t_on/t_f (35 ns / 24 ns) supports >10 MHz digital signaling in deterministic control loops.

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP switching transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
2SA1037AK-TL-E	V_CEO = -50 V, I_C = -150 mA, f_T = 180 MHz - lower current, higher f_T per mA.	Optimized for low-power signal switching, not high-current load driving.	Select when base drive is limited and switching speed >100 MHz is required at sub-200 mA loads.
MJD2955G	V_CEO = -60 V, I_C = -10 A, TO-220 package - higher power, larger footprint, slower f_T (100 MHz).	Suitable for >5 A industrial motor controls but requires heatsink and PCB area.	Choose for higher current or higher voltage margin where TO-92 footprint is not constrained.

Compared with 2SA2127-AE, 2SA1037AK-TL-E offers superior small-signal speed but insufficient current capacity for relay/lamp loads, while MJD2955G delivers higher power handling at the cost of board space and reduced bandwidth-making 2SA2127-AE optimal for compact, medium-current discrete switching.

Availability

2SA2127-AE is available at Aetrix Electronics and suitable for voltage regulators, relay drivers, and lamp drivers requiring stable component supply, long-term industrial availability, and RoHS-compliant packaging.

Supply support for 2SA2127-AE 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier focused on energy-efficient innovation for automotive, industrial, cloud, and IoT applications.

The 2SA2127-AE belongs to onsemi's general-purpose bipolar transistor product line, engineered for reliable, low-loss switching in cost-sensitive industrial control and power management systems.

FAQ

What is the maximum continuous collector current rating for the 2SA2127-AE?

The 2SA2127-AE has a maximum continuous collector current (I_C) rating of -2 A at T_a = 25°C. Derating applies above 25°C ambient per the PC vs. Ta curve; at 75°C, usable I_C drops to approximately -1.3 A. This rating is validated under free-air conditions with no heatsink and defines safe DC operation in relay, lamp, and regulator applications.

Does the 2SA2127-AE support pulsed operation beyond its continuous current rating?

Yes, the 2SA2127-AE supports pulsed collector current (I_CP) up to -4 A, specified for pulse widths ≤ 100 μs and duty cycles ≤ 1%. This capability is enabled by its wide Safe Operating Area (ASO) and is confirmed in the datasheet's SOA graph. It allows handling of inductive kickback and lamp inrush without secondary breakdown.

What is the pin configuration of the 2SA2127-AE in the MP package?

The 2SA2127-AE in the MP (TO-92 compatible) package has a fixed pinout: Pin 1 = Emitter, Pin 2 = Collector, Pin 3 = Base - viewed with flat side facing outward and leads pointing down. This matches JEDEC TO-226AE orientation and is verified in the "Electrical Connection" diagram on page 2 of the official datasheet.

How does the 2SA2127-AE's saturation voltage compare to similar PNP transistors?

The 2SA2127-AE achieves V_CE(sat) = -0.2 to -0.4 V at I_C = -1 A and I_B = -50 mA, which is 20–30% lower than standard PNP transistors like the 2N2907A (-0.6 to -0.8 V). This reduction directly lowers conduction loss and thermal stress, especially in high-duty-cycle applications such as constant-current lamp drivers.

Is the 2SA2127-AE lead-free and RoHS compliant?

Yes, the 2SA2127-AE is marked "Pb Free" in the Ordering Information table and conforms to RoHS Directive 2011/65/EU. The "VR" packing code indicates lead-free plating and halogen-free molding compound. Full compliance documentation, including test reports, is available through onsemi's quality portal for qualified customers.

2SA2127-AE Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

Package/Case:: TO-226-3, TO-92-3 Long Body, Formed Leads

Packaging:: Bulk

Product Status:: Obsolete

Transistor Type:: PNP

Current - Collector (Ic) (Max):: 2 A

Voltage - Collector Emitter Breakdown (Max):: 50 V

Vce Saturation (Max) @ Ib, Ic:: 400mV @ 50mA, 1A

Current - Collector Cutoff (Max):: 1µA (ICBO)

DC Current Gain (hFE) (Min) @ Ic, Vce:: 200 @ 100mA, 2V

Power - Max:: 1 W

Frequency - Transition:: 420MHz

Operating Temperature:: 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: 3-MP

2SA2127-AE FAQ

1.How can I place an order for 2SA2127-AE through Aetrix?

Please submit a Request for Quotation (RFQ) for 2SA2127-AE 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 2SA2127-AE reliable?

The price and inventory of 2SA2127-AE are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 2SA2127-AE is usually 5 days.

3.What payment methods are accepted for 2SA2127-AE?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 2SA2127-AE transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for 2SA2127-AE?

2SA2127-AE orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your 2SA2127-AE 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 2SA2127-AE?

For technical support, including 2SA2127-AE datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 2SA2127-AE requirements.

6.How does Aetrix verify that 2SA2127-AE is sourced from the original manufacturer or authorized distributors?

All 2SA2127-AE 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 2SA2127-AE meets industry standards.

7.What is the process for return or replacement of 2SA2127-AE?

All 2SA2127-AE units undergo pre-shipment inspection (PSI). If there is an issue with 2SA2127-AE, 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 2SA2127-AE part is unused and in its original packaging.

Return procedure for 2SA2127-AE:

1.Submit a request within 90 days.

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

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