Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

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

onsemi MPSA18RLRP

Name: MPSA18RLRP
Brand: onsemi
SKU: MPSA18RLRP
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: MPSA18RLRP

Manufacturer:: onsemi

Category:: Single Bipolar Transistors

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

Datasheet:: MPSA18RLRP.pdf

Description:: TRANS NPN 45V 0.2A TO92

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:4,322

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

MPSA18RLRP from onsemi is an NPN silicon low-noise general-purpose transistor in TO-92 package, rated for V_CEO = 45 V, I_C = 200 mA, and P_D = 625 mW at T_A = 25°C, with h_FE up to 1500 and f_T = 100–160 MHz - widely used in audio preamplifier stages and signal conditioning circuits where low noise and high gain are critical.

For engineers reviewing the MPSA18RLRP datasheet, pinout, applications, or equivalent options, key selection considerations include its 0.5 dB noise figure at 100 Hz (R_S = 1 kΩ), 6.5 nV/√Hz equivalent input noise voltage, TO-92 mechanical compatibility, Pb-free availability (MPSA18RLRPG), and verified performance across −55°C to +150°C junction temperature range.

Technical Context

The MPSA18RLRP operates as a discrete NPN bipolar junction transistor optimized for low-noise amplification in small-signal applications. Its design emphasizes high DC current gain (h_FE ≥ 400 at I_C = 10 mA) and broadband RF capability (f_T ≥ 100 MHz), supported by low C_cb (1.7–3.0 pF) and C_eb (5.6–6.5 pF) capacitances.

Noise performance is characterized under controlled conditions: NF = 0.5 dB typical at 100 Hz with R_S = 1 kΩ, and VT = 6.5 nV/√Hz total noise voltage. The device exhibits stable h_FE over temperature (−55°C to +125°C), with V_BE(on) = 0.6–0.7 V and V_CE(sat) ≤ 0.3 V at I_C/I_B = 10.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	45 V - Maximum safe collector-emitter voltage before breakdown; enables use in 24–36 V analog signal chains.
I_C (continuous)	200 mA - Supports medium-current preamp and driver stages without thermal derating at ambient.
h_FE	400–1500 - High and wide DC gain range allows flexible biasing and stable closed-loop gain control.
f_T	100–160 MHz - Sufficient bandwidth for audio, IF, and low-MHz RF amplification without instability.
NF (100 Hz)	0.5 dB typical - Ultra-low noise figure critical for microphone preamps and sensor front-ends.
V_CE(sat)	≤ 0.3 V @ I_C = 50 mA - Ensures minimal voltage drop and power loss in saturated switching or linear operation.
P_D @ T_A	625 mW - Enables continuous operation in standard through-hole PCB layouts with natural convection cooling.

Pinout & Package

Package: TO-92 (Case 29-11, Style 1), 3-lead through-hole plastic package with standardized lead spacing (P = 2.54 mm), compatible with manual soldering and wave soldering processes per ON Semiconductor's packaging specifications.

Pin/Terminal	Circuit Role	Design Meaning
1	Emitter	Current sink terminal; connects to ground or bias network; polarity defines NPN operation.
2	Base	Control input; requires ~0.65 V forward bias and microamp-level drive for full conduction.
3	Collector	Current source terminal; connects to supply rail or load; handles up to 45 V and 200 mA.

Key Features

Feature	Design Value
Low-noise amplification	0.5 dB NF at 100 Hz enables high-fidelity audio and precision sensor signal recovery.
High DC current gain	h_FE ≥ 400 at 10 mA ensures robust small-signal amplification with minimal base drive.
Wideband frequency response	f_T ≥ 100 MHz supports stable gain up to VHF frequencies in tuned amplifier designs.
Thermal ruggedness	Junction temperature range of −55°C to +150°C supports industrial and automotive under-hood environments.
Pb-free option available	MPSA18RLRPG variant meets RoHS requirements without performance trade-offs.

Applications

Microphone Pre-amplifier	Instrumentation Amplifier Input Stage
Use Scenario: Low-level electret microphone output (mV-range) is amplified before ADC sampling in voice-recognition modules. IC Role / Device Role / Timing Role: Discrete NPN transistor configured in common-emitter topology providing first-stage voltage gain and impedance transformation. Use Value: 0.5 dB noise figure and 6.5 nV/√Hz input-referred noise preserve SNR in sub-10 mV signals without requiring costly op-amps.	Use Scenario: Front-end amplification of thermocouple or strain gauge outputs in data acquisition systems. IC Role / Device Role / Timing Role: High-h_FE, low-drift NPN transistor used in differential pair or cascode configuration for initial signal conditioning. Use Value: Stable h_FE across −55°C to +125°C and low V_CE(sat) minimize offset drift and power dissipation in precision analog paths.
RF Intermediate Frequency Amplifier	Low-Voltage Analog Switch Driver
Use Scenario: 10.7 MHz IF amplification in AM/FM radio receivers prior to demodulation. IC Role / Device Role / Timing Role: Tuned common-emitter amplifier with LC collector load delivering selective gain at fixed frequency. Use Value: f_T ≥ 100 MHz and low C_cb/C_eb enable stable, high-Q resonant amplification without neutralization.	Use Scenario: Driving low-power analog switches (e.g., CMOS multiplexers) from microcontroller GPIO pins. IC Role / Device Role / Timing Role: Single-transistor level shifter and current booster between 3.3 V logic and 5–12 V analog switch control rails. Use Value: V_CE(sat) ≤ 0.3 V ensures <100 mV dropout at 20 mA drive current, preserving timing margins and reducing heat.

Microphone Pre-amplifier

Instrumentation Amplifier Input Stage

Use Scenario: Low-level electret microphone output (mV-range) is amplified before ADC sampling in voice-recognition modules.

IC Role / Device Role / Timing Role: Discrete NPN transistor configured in common-emitter topology providing first-stage voltage gain and impedance transformation.

Use Value: 0.5 dB noise figure and 6.5 nV/√Hz input-referred noise preserve SNR in sub-10 mV signals without requiring costly op-amps.

Use Scenario: Front-end amplification of thermocouple or strain gauge outputs in data acquisition systems.

IC Role / Device Role / Timing Role: High-h_FE, low-drift NPN transistor used in differential pair or cascode configuration for initial signal conditioning.

Use Value: Stable h_FE across −55°C to +125°C and low V_CE(sat) minimize offset drift and power dissipation in precision analog paths.

RF Intermediate Frequency Amplifier

Low-Voltage Analog Switch Driver

Use Scenario: 10.7 MHz IF amplification in AM/FM radio receivers prior to demodulation.

IC Role / Device Role / Timing Role: Tuned common-emitter amplifier with LC collector load delivering selective gain at fixed frequency.

Use Value: f_T ≥ 100 MHz and low C_cb/C_eb enable stable, high-Q resonant amplification without neutralization.

Use Scenario: Driving low-power analog switches (e.g., CMOS multiplexers) from microcontroller GPIO pins.

IC Role / Device Role / Timing Role: Single-transistor level shifter and current booster between 3.3 V logic and 5–12 V analog switch control rails.

Use Value: V_CE(sat) ≤ 0.3 V ensures <100 mV dropout at 20 mA drive current, preserving timing margins and reducing heat.

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-noise NPN transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
BC548C	Lower h_FE (420–800), higher NF (≈2.5 dB at 1 kHz), same TO-92 package.	Less suitable for ultra-low-noise audio; acceptable for general-purpose switching and medium-gain amplification.	Select BC548C only when noise <1 dB is not required and cost sensitivity outweighs gain/noise optimization.
2N5088	Higher h_FE (600–1000), lower NF (0.3 dB typ.), but lower V_CEO (30 V) and I_C (50 mA).	Better for ultra-low-noise mic preamps below 30 V supply; unsuitable for higher-voltage or higher-current loads.	Choose 2N5088 when ultimate noise performance is prioritized and operating voltage stays ≤30 V.

Compared with BC548C and 2N5088, the MPSA18RLRP delivers the best balance of high voltage rating (45 V), high current capability (200 mA), and low noise (0.5 dB), making it uniquely suited for industrial-grade audio and instrumentation designs requiring both headroom and fidelity.

Availability

MPSA18RLRP is available at Aetrix Electronics and suitable for audio preamplifiers, instrumentation signal conditioning, and RF intermediate-frequency amplifiers requiring stable component supply, consistent parametric performance, and long-term manufacturing continuity.

Supply support for MPSA18RLRP 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, serving automotive, industrial, cloud, medical, and IoT markets with differentiated silicon solutions.

The MPSA18RLRP belongs to onsemi's legacy general-purpose bipolar transistor product line, engineered specifically for low-noise, high-gain analog signal amplification in cost-sensitive, high-reliability applications.

FAQ

What is the maximum collector-emitter voltage rating for the MPSA18RLRP?

The MPSA18RLRP has a maximum collector-emitter voltage (V_CEO) rating of 45 Vdc, as specified in the Absolute Maximum Ratings table. This rating applies under DC conditions with I_B = 0 and defines the upper limit before avalanche breakdown occurs. Exceeding this voltage risks permanent device damage, and derating is recommended in high-temperature or pulsed applications.

Is the MPSA18RLRP suitable for low-noise audio amplifier designs?

Yes, the MPSA18RLRP is explicitly characterized as a low-noise transistor with a typical noise figure of 0.5 dB at 100 Hz (R_S = 1 kΩ) and 6.5 nV/√Hz equivalent input noise voltage. These parameters are measured and guaranteed per the official onsemi datasheet, making the MPSA18RLRP well-suited for microphone preamplifiers, phono stages, and other high-SNR analog signal paths where noise minimization is critical.

What package type and pin configuration does the MPSA18RLRP use?

The MPSA18RLRP uses the TO-92 (Case 29-11, Style 1) through-hole plastic package with three leads arranged in emitter-base-collector order (Pin 1 = Emitter, Pin 2 = Base, Pin 3 = Collector). This configuration is standardized across all MPSA18 variants and confirmed in the marking diagram and package dimensions section of the onsemi datasheet.

Does the MPSA18RLRP have a Pb-free version, and how is it designated?

Yes, the Pb-free version of the MPSA18RLRP is designated as MPSA18RLRPG. It shares identical electrical and thermal specifications with the MPSA18RLRP but complies with RoHS Directive 2011/65/EU. Both variants use the same TO-92 package and are supplied in 2000-unit ammo packs, as documented in the official ON Semiconductor ordering information table.

What is the DC current gain (h_FE) range for the MPSA18RLRP at typical operating conditions?

The MPSA18RLRP exhibits a DC current gain (h_FE) ranging from 400 to 1500, depending on collector current and test conditions. At I_C = 10 mA and V_CE = 5.0 Vdc, the minimum h_FE is 400, while typical values reach 500–1150 and maximum values extend to 1500. This wide gain spread is fully characterized in the Electrical Characteristics table of the onsemi datasheet for MPSA18RLRP.

MPSA18RLRP Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

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

Packaging:: Tape & Box (TB)

Product Status:: Obsolete

Transistor Type:: NPN

Current - Collector (Ic) (Max):: 200 mA

Voltage - Collector Emitter Breakdown (Max):: 45 V

Vce Saturation (Max) @ Ib, Ic:: 300mV @ 5mA, 50mA

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

DC Current Gain (hFE) (Min) @ Ic, Vce:: 500 @ 10mA, 5V

Power - Max:: 625 mW

Frequency - Transition:: 160MHz

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

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

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

MPSA18RLRP FAQ

1.How can I place an order for MPSA18RLRP through Aetrix?

Please submit a Request for Quotation (RFQ) for MPSA18RLRP 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 MPSA18RLRP reliable?

The price and inventory of MPSA18RLRP are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MPSA18RLRP is usually 5 days.

3.What payment methods are accepted for MPSA18RLRP?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MPSA18RLRP transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for MPSA18RLRP?

MPSA18RLRP orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your MPSA18RLRP 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 MPSA18RLRP?

For technical support, including MPSA18RLRP datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MPSA18RLRP requirements.

6.How does Aetrix verify that MPSA18RLRP is sourced from the original manufacturer or authorized distributors?

All MPSA18RLRP 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 MPSA18RLRP meets industry standards.

7.What is the process for return or replacement of MPSA18RLRP?

All MPSA18RLRP units undergo pre-shipment inspection (PSI). If there is an issue with MPSA18RLRP, 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 MPSA18RLRP part is unused and in its original packaging.

Return procedure for MPSA18RLRP:

1.Submit a request within 90 days.

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

Tech Hub

2026-09-09 Counterfeit Electronic Components: How to Detect, Authenticate, and Test Suspect Parts

Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …

2026-09-08 Obsolete Electronic Components: How to Source and Evaluate Replacements

A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.

2026-09-07 TTL vs CMOS Logic Levels: 74HC and 74HCT Compatibility Explained

TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.

2026-09-04 Logic Level Shifter: How to Connect 3.3V and 5V Logic Safely

A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.

2026-09-03 74HC595 vs TPIC6B595: Output Drive, Pinout, Current, and Load Selection

The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…

2026-09-02 74HC595 Pinout, Timing, Output Current, and Applications

The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…

2026-09-01 Latch vs Flip-Flop: Timing, Differences and Design Choices

A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…

2026-08-30 D Latch Circuit: Truth Table, Timing, ICs and Applications

A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …

2026-08-28 SR Latch Explained: NOR and NAND Circuits, Truth Tables, and Applications

An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…

2026-08-27 Latch Circuit: SR and D Latches, Truth Tables, Timing, and Applications

Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…