onsemi MPS651G

Overview

MPS651G from onsemi is an NPN bipolar junction transistor (BJT) designed for general-purpose amplification and switching in medium-power linear and digital circuits. It features 60 V collector-emitter breakdown voltage (V_(BR)CEO), 2.0 A continuous collector current (I_C), and 1.5 W total power dissipation at T_C = 25°C, operating across −55°C to +150°C junction temperature range.

For engineers reviewing the MPS651G datasheet, pinout, applications, or equivalent options, this device is commonly selected for DC-DC converter drivers, relay drivers, and low-frequency amplifier stages where robust SOA, Pb-free TO-92 packaging, and stable h_FE ≥75 at 50–500 mA are required.

Technical Context

This NPN transistor operates with a minimum DC current gain (h_FE) of 75 at I_C = 50 mA and V_CE = 2.0 V, maintaining h_FE ≥40 up to I_C = 2.0 A. Its safe operating area (SOA) is defined by thermal, second breakdown, and wire bond limits - validated for pulsed operation up to 100 s at V_CE ≤ 20 V and I_C ≤ 2.0 A.

It exhibits V_CE(sat) ≤ 0.5 V at I_C = 2.0 A / I_B = 200 mA and V_BE(sat) ≤ 1.2 V under same conditions, with f_T = 75 MHz at I_C = 50 mA, V_CE = 5.0 V, enabling use in audio-frequency switching and low-speed logic interfacing.

Key Specifications

Pinout & Package

Package: TO-92 (Case 29-11), Pb-free, straight or bent lead options. Dimensions per ANSI Y14.5M: body height 4.45–5.20 mm, lead pitch 2.54 mm, emitter-base-collector pinout confirmed per marking diagram and mechanical drawing.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN general-purpose transistor applications.

Compared with MMBT651LT1G and BC639, the MPS651G provides the highest combination of current (2.0 A), power (1.5 W), and voltage (60 V) in a standardized TO-92 footprint - making it optimal for through-hole medium-power switching where thermal derating and SOA integrity are design-critical.

Availability

MPS651G is available at Aetrix Electronics and suitable for relay drivers, DC-DC converter switches, and linear amplifier stages requiring stable component supply, long-term manufacturability, and Pb-free compliance.

Supply support for MPS651G 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 delivering energy-efficient silicon solutions for automotive, industrial, cloud, medical, and IoT applications.

The MPS651G belongs to onsemi's legacy general-purpose BJT product line, engineered for reliability in industrial control, power management, and signal conditioning circuits where cost-effective, through-hole discrete switching and amplification are needed.

FAQ

What is the maximum continuous collector current for MPS651G?

The MPS651G supports a maximum continuous collector current (I_C) of 2.0 A at T_C = 25°C. Derating applies above 25°C - 12 mW/°C for case-mounted operation. This rating is validated under SOA constraints shown in Figure 7 of the official datasheet, and must be verified against actual board-level thermal performance in the target application.

Does MPS651G have Pb-free packaging?

Yes, the MPS651G is supplied in a Pb-free TO-92 package (Case 29-11), compliant with RoHS Directive 2011/65/EU. The "G" suffix explicitly denotes Pb-free construction, and the device meets onsemi's Soldering and Mounting Techniques Reference Manual requirements for lead-free reflow profiles.

What is the DC current gain (h_FE) range for MPS651G at 500 mA collector current?

At I_C = 500 mA and V_CE = 2.0 V, the MPS651G guarantees h_FE ≥75 (minimum), per the Electrical Characteristics table. Typical values exceed 100, but design margining should use the min spec. This gain remains stable across −55°C to +125°C, as confirmed in Figure 1 of the MPS650/D datasheet.

Can MPS651G replace MPS650G in existing designs?

Yes, the MPS651G can replace MPS650G where higher voltage blocking is required: MPS651G offers 60 V V_(BR)CEO versus 40 V for MPS650G, with identical pinout, package, and gain characteristics. No PCB changes are needed, but verify that the increased V_(BR)CBO (80 V vs. 60 V) and SOA curves align with system transient requirements.

What is the thermal resistance junction-to-case (R_θJC) for MPS651G?

The MPS651G has a thermal resistance junction-to-case (R_θJC) of 83.3°C/W, as specified in the Thermal Characteristics table. This value assumes proper mechanical contact between the TO-92 case and heatsink or copper pour; actual board-level R_θJA will vary significantly based on layout and airflow.