onsemi MPSW51AG

Overview

MPSW51AG from onsemi is a PNP silicon bipolar junction transistor rated for −40 V_CEO, −50 V_CBO, −5.0 V_EBO, −1000 mA continuous collector current, and 2.5 W total dissipation at T_C = 25°C, used in high-current switching and linear amplification circuits such as power supply regulators and relay drivers.

For engineers reviewing the MPSW51AG datasheet, pinout, applications, or equivalent options, key selection considerations include its TO-92 package thermal resistance (R_JC = 50°C/W), DC current gain (h_FE ≥ 60 at I_C = −100 mA), V_CE(sat) ≤ −0.7 V, and safe operating area limits under pulsed and continuous conditions.

Technical Context

The MPSW51AG operates as a medium-power PNP BJT with verified breakdown ratings of −40 V_CEO and −50 V_CBO, supporting robust voltage margin in negative-rail switching applications. Its f_T = 50 MHz enables use in audio-frequency amplification and fast-switching control loops.

Thermal design is constrained by R_JA = 125°C/W (ambient) and R_JC = 50°C/W (case), requiring heatsinking for sustained >1.25 W operation. C_obo = 30 pF at V_CB = −10 V supports stable performance in low-noise bias networks.

Key Specifications

Pinout & Package

Package: TO-92 (Case 29-10, Style 1), Pb-free, 1 W rating at T_A = 25°C, with bent or straight lead options.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPSW51G and PN2907A, the MPSW51AG delivers superior current handling (−1000 mA vs. −600 mA) and thermal capability (2.5 W vs. 0.625 W), making it the preferred choice for industrial loads demanding both voltage margin and sustained power delivery.

Availability

MPSW51AG is available at Aetrix Electronics and suitable for industrial relay drivers, linear voltage regulators, DC motor H-bridge complements, and LED constant-current drivers requiring stable component supply and RoHS-compliant sourcing.

Supply support for MPSW51AG 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 manufacturer specializing in energy-efficient power, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The MPSW51AG belongs to onsemi's general-purpose bipolar transistor product line, engineered for robust high-current switching and linear amplification in harsh industrial environments with extended temperature and reliability requirements.

FAQ

What is the maximum continuous collector current rating for the MPSW51AG?

The MPSW51AG is rated for −1000 mAdc continuous collector current at T_C = 25°C. Derating applies above 25°C case temperature per the datasheet's 20 mW/°C slope. This rating assumes proper heatsinking and PCB copper area to maintain thermal resistance below specified limits. The MPSW51AG must not be operated beyond this current without verifying junction temperature rise using R_JC = 50°C/W and ambient or case temperature measurements.

Does the MPSW51AG have Pb-free and RoHS-compliant packaging?

Yes, the MPSW51AG uses a Pb-free TO-92 package and is RoHS compliant, as confirmed in the official onsemi datasheet (Rev. 5, June 2013). The "G" suffix denotes Pb-free construction, and the device carries the required marking per EU RoHS Directive 2011/65/EU. No lead content is present in the terminations or mold compound, and soldering profiles follow onsemi's Pb-free guidelines in SOLDERRM/D.

What is the DC current gain (h_FE) of the MPSW51AG at different operating points?

The MPSW51AG specifies h_FE ≥ 60 at I_C = −100 mAdc, V_CE = −1.0 Vdc; ≥ 50 at I_C = −1000 mAdc, V_CE = −1.0 Vdc; and ≥ 55 at I_C = −10 mAdc, V_CE = −1.0 Vdc. These values are minimum guaranteed parameters measured at T_A = 25°C. The MPSW51AG exhibits stable gain across its operating range, supporting predictable base drive design in both switching and linear applications.

Can the MPSW51AG be used in high-frequency amplifier circuits?

The MPSW51AG has an f_T of 50 MHz at I_C = −50 mAdc, V_CE = −10 Vdc, making it suitable for audio-frequency amplification and low-speed switching up to ~10–20 MHz. It is not optimized for RF or microwave applications. For stable small-signal gain, biasing must remain within the linear active region, and layout must minimize parasitic capacitance - especially given its C_obo = 30 pF. The MPSW51AG performs best in sub-10 MHz analog stages and PWM-driven power control.

What is the safe operating area (SOA) limitation for the MPSW51AG in pulse applications?

The MPSW51AG SOA curve (Figure 7) defines absolute maximum combinations of V_CE and I_C under pulsed conditions: for 1 ms pulses at ≤10% duty cycle, it supports up to −40 V and −500 mA simultaneously. At DC, thermal limits constrain operation to ≤−1000 mA only below −2.5 V_CE. Exceeding SOA boundaries risks second breakdown. The MPSW51AG must be applied within these validated boundaries - especially in inductive switching - using snubbers or clamps where needed.