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

onsemi MPS3646

Name: MPS3646
Brand: onsemi
SKU: MPS3646
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: MPS3646

Manufacturer:: onsemi

Category:: Single Bipolar Transistors

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

Datasheet:: MPS3646.pdf

Description:: TRANS NPN 15V 0.3A TO92

Quantity:: RFQ Add To RFQ list

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Product details

Overview

MPS3646 from onsemi is an NPN silicon switching transistor in TO-92 (CASE 29−11) package, rated for V_CEO = 15 V, I_C = 300 mA continuous, and f_T = 350 MHz, with V_CE(sat) ≤ 0.2 V at I_C = 30 mA / I_B = 3 mA - used in low-voltage digital logic interface and signal switching circuits.

For engineers reviewing the MPS3646 datasheet, pinout, applications, or equivalent options, key selection considerations include its 15 V V_CEO rating, 300 mA DC current capability, fast switching times (t_on ≤ 18 ns, t_off ≤ 28 ns), thermal resistance R_JA = 200 °C/W, and TO-92 mechanical compatibility with legacy through-hole designs.

Technical Context

The MPS3646 is a general-purpose NPN bipolar junction transistor optimized for low-power switching applications where fast turn-on/turn-off and low saturation voltage are required. It operates with base-emitter forward bias and collector-emitter conduction under controlled current gain (h_FE = 30–120 at I_C = 30–100 mA).

Its dynamic performance is characterized by t_on ≤ 18 ns, t_off ≤ 28 ns, and f_T = 350 MHz at I_C = 30 mA / V_CE = 10 V, confirming suitability for medium-speed digital switching up to ~10 MHz clocked logic interfaces and pulse amplification.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	15 Vdc - maximum safe collector-emitter voltage under open-base conditions; defines upper rail limit in 5 V or 12 V logic-level switching.
I_C (continuous)	300 mAdc - supports driving small relays, LEDs, or gate inputs without external heat sinking at ambient temperatures ≤ 25°C.
h_FE (min)	30 at I_C = 30 mAdc / V_CE = 0.4 V - ensures reliable saturation with modest base drive (e.g., 1 mA base current switches ≥30 mA load).
V_CE(sat)	0.2 V max at I_C = 30 mAdc / I_B = 3 mAdc - minimizes power loss (<6 mW) and voltage drop in active-low switch configurations.
f_T	350 MHz - enables use in RF predriver stages or high-speed pulse shaping up to ~30 MHz fundamental frequency.
t_off	28 ns max - supports clean edge transitions in 20–30 MHz digital waveform generation and TTL-compatible buffering.

Pinout & Package

Package: TO-92 (CASE 29−11, STYLE 1), through-hole, epoxy-molded plastic case with 3.43 mm radius contour and 12.70 mm body length (K dimension). Lead finish is Pb-free per onsemi specification.

Pin/Terminal	Circuit Role	Design Meaning
1 (Emitter)	Current sink terminal	Connected to ground or low-side return path; requires low-impedance PCB trace to minimize V_BE error in precision switching.
2 (Base)	Control input	Receives current-limited drive (typically 1–10 mA); base resistor must be sized to ensure h_FE-based saturation across temperature.
3 (Collector)	Current source terminal	Connects to load and positive supply; layout must avoid parasitic inductance to preserve t_r/t_f performance.

Key Features

Feature	Design Value
Pb-free packaging	Complies with RoHS Directive 2011/65/EU; no lead content in die attach, bond wires, or external terminations.
High f_T	350 MHz enables stable operation in broadband amplifier and pulse generator front-end stages without external compensation.
Low V_CE(sat)	0.2 V typical at I_C/I_B = 10 ensures >98% efficiency in 3.3 V or 5 V load switching applications.
Wide T_J range	−55°C to +150°C junction operation supports deployment in automotive under-hood and industrial control environments.

Applications

Logic-Level Signal Switching	LED Driver Interface
Use Scenario: Isolating microcontroller GPIO pins from higher-current loads in embedded control panels. IC Role / Device Role / Timing Role: NPN switch enabling/disabling 20 mA LED indicators or optocoupler inputs with <20 ns edge fidelity. Use Value: Eliminates need for level-shifting ICs while maintaining TTL-compatible rise/fall times and low quiescent current in standby.	Use Scenario: Driving discrete red/green status LEDs in industrial HMIs with 3.3 V MCU outputs. IC Role / Device Role / Timing Role: Low-saturation switch providing precise on/off control without color shift or brightness variation due to V_CE(sat) drift. Use Value: Delivers consistent LED luminance across −40°C to +85°C ambient via stable h_FE and minimal V_CE(sat) temperature coefficient.
Small-Relay Driver	Digital Pulse Amplifier
Use Scenario: Activating 5 V, 100 Ω coil relays in programmable logic controllers. IC Role / Device Role / Timing Role: Sustained 300 mA collector current switch with t_off ≤ 28 ns to suppress back-EMF-induced contact chatter. Use Value: Reduces relay coil energy dissipation by 35% versus standard 2N3904 due to lower V_CE(sat) and faster deactivation.	Use Scenario: Boosting 0–3.3 V square-wave signals to 0–5 V levels for FPGA clock distribution networks. IC Role / Device Role / Timing Role: Emitter-follower configured amplifier preserving edge integrity with f_T-limited bandwidth up to 100 MHz. Use Value: Maintains <10% overshoot and <1 ns jitter accumulation over 10 cm FR4 traces at 25 MHz repetition rate.

Logic-Level Signal Switching

LED Driver Interface

Use Scenario: Isolating microcontroller GPIO pins from higher-current loads in embedded control panels.

IC Role / Device Role / Timing Role: NPN switch enabling/disabling 20 mA LED indicators or optocoupler inputs with <20 ns edge fidelity.

Use Value: Eliminates need for level-shifting ICs while maintaining TTL-compatible rise/fall times and low quiescent current in standby.

Use Scenario: Driving discrete red/green status LEDs in industrial HMIs with 3.3 V MCU outputs.

IC Role / Device Role / Timing Role: Low-saturation switch providing precise on/off control without color shift or brightness variation due to V_CE(sat) drift.

Use Value: Delivers consistent LED luminance across −40°C to +85°C ambient via stable h_FE and minimal V_CE(sat) temperature coefficient.

Small-Relay Driver

Digital Pulse Amplifier

Use Scenario: Activating 5 V, 100 Ω coil relays in programmable logic controllers.

IC Role / Device Role / Timing Role: Sustained 300 mA collector current switch with t_off ≤ 28 ns to suppress back-EMF-induced contact chatter.

Use Value: Reduces relay coil energy dissipation by 35% versus standard 2N3904 due to lower V_CE(sat) and faster deactivation.

Use Scenario: Boosting 0–3.3 V square-wave signals to 0–5 V levels for FPGA clock distribution networks.

IC Role / Device Role / Timing Role: Emitter-follower configured amplifier preserving edge integrity with f_T-limited bandwidth up to 100 MHz.

Use Value: Maintains <10% overshoot and <1 ns jitter accumulation over 10 cm FR4 traces at 25 MHz repetition rate.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
2N3904	V_CEO = 40 V, I_C = 200 mA, f_T = 300 MHz, V_CE(sat) = 0.2 V @ I_C/I_B = 10 - lower current rating and slightly reduced speed.	Preferred where higher V_CEO margin is needed but load current stays below 200 mA; less suitable for 300 mA relay drivers.	Select 2N3904 only if design requires >15 V collector swing or legacy footprint compatibility with identical pinout.
BC547B	V_CEO = 45 V, I_C = 100 mA, h_FE = 200–450, V_CE(sat) = 0.25 V @ I_C/I_B = 10 - higher gain but lower current and slower switching (t_off ≈ 300 ns).	Better for linear amplification or low-current analog switching; not recommended for >100 mA pulsed loads or sub-50 ns timing-critical paths.	Choose BC547B when high DC gain is prioritized over speed and current capacity - e.g., sensor signal conditioning with low base drive.

Compared with 2N3904 and BC547B, the MPS3646 delivers superior combination of 300 mA current handling, 350 MHz f_T, and 28 ns t_off, making it optimal for compact, high-efficiency digital switching where both speed and drive strength are constrained by board space and thermal budget.

Availability

MPS3646 is available at Aetrix Electronics and suitable for logic-level signal switching, LED driver interface, and small-relay driver applications requiring stable component supply, long-term manufacturability, and RoHS-compliant sourcing.

Supply support for MPS3646 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 specializing in energy-efficient power management, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The MPS3646 belongs to onsemi's general-purpose bipolar transistor product line, designed specifically for cost-sensitive, high-volume switching applications demanding reliability, Pb-free compliance, and proven TO-92 mechanical interoperability.

FAQ

What is the maximum continuous collector current rating for the MPS3646?

The MPS3646 has a maximum continuous collector current (I_C) rating of 300 mAdc at T_A = 25°C. Derating applies above 25°C at 5.0 mW/°C for free-air operation. This rating allows the MPS3646 to reliably drive moderate-current loads such as indicator LEDs, small solenoids, or logic-level buffers without external heatsinking in typical ambient conditions.

Does the MPS3646 support Pb-free assembly processes?

Yes, the MPS3646 is manufactured in a Pb-free package per onsemi's specification and complies with RoHS Directive 2011/65/EU. The device uses lead-free solderable terminations and is qualified for standard reflow and wave soldering profiles, including JEDEC J-STD-020 moisture sensitivity level (MSL) 1 handling.

What is the typical DC current gain (h_FE) of the MPS3646 at 30 mA collector current?

The MPS3646 exhibits a minimum h_FE of 30 at I_C = 30 mAdc and V_CE = 0.4 Vdc, with typical values reaching 80–100 under the same conditions. This gain ensures robust saturation with base currents as low as 0.3–1.0 mA, making the MPS3646 well-suited for direct GPIO interfacing from 3.3 V microcontrollers.

Can the MPS3646 be used in high-frequency amplifier circuits?

The MPS3646 has an f_T of 350 MHz, supporting stable small-signal amplification up to ~100 MHz in common-emitter configuration. However, it is not optimized for RF power amplification; its primary design intent is fast, efficient switching. For amplifier use, bias stability and matching network design must account for its C_ibo = 9.0 pF and C_obo = 5.0 pF capacitances.

What are the absolute maximum ratings for junction temperature and storage temperature of the MPS3646?

The MPS3646 has an operating and storage junction temperature range of −55°C to +150°C. This wide range enables deployment in harsh environments such as automotive engine compartments, industrial motor controls, and outdoor equipment enclosures where thermal cycling and extended ambient extremes are expected.

MPS3646 Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

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

Packaging:: Bulk

Product Status:: Obsolete

Transistor Type:: NPN

Current - Collector (Ic) (Max):: 300 mA

Voltage - Collector Emitter Breakdown (Max):: 15 V

Vce Saturation (Max) @ Ib, Ic:: 500mV @ 30mA, 300mA

Current - Collector Cutoff (Max):: 500nA

DC Current Gain (hFE) (Min) @ Ic, Vce:: 30 @ 30mA, 400mV

Power - Max:: 625 mW

Frequency - Transition:: 350MHz

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

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-92 (TO-226)

MPS3646 FAQ

1.How can I place an order for MPS3646 through Aetrix?

Please submit a Request for Quotation (RFQ) for MPS3646 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 MPS3646 reliable?

The price and inventory of MPS3646 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MPS3646 is usually 5 days.

3.What payment methods are accepted for MPS3646?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MPS3646 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for MPS3646?

MPS3646 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your MPS3646 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 MPS3646?

For technical support, including MPS3646 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MPS3646 requirements.

6.How does Aetrix verify that MPS3646 is sourced from the original manufacturer or authorized distributors?

All MPS3646 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 MPS3646 meets industry standards.

7.What is the process for return or replacement of MPS3646?

All MPS3646 units undergo pre-shipment inspection (PSI). If there is an issue with MPS3646, 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 MPS3646 part is unused and in its original packaging.

Return procedure for MPS3646:

1.Submit a request within 90 days.

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

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