onsemi BD180G

Overview

BD180G from onsemi is a plastic medium-power silicon PNP transistor designed for 5.0–10 W audio amplifiers and drivers in complementary or quasi-complementary circuits, with V_CEO = 80 V, I_C = 1.0 A, P_D = 30 W at T_C = 25 °C, h_FE = 40–250 (at I_C = 0.15 A), and TO-225 package.

For engineers reviewing the BD180G datasheet, pinout, applications, or equivalent options, key selection criteria include safe operating area (SOA) compliance in Class-B audio output stages, thermal resistance R_θJC = 4.16 °C/W, V_CE(sat) ≤ 0.8 V at I_C = 1.0 A/I_B = 0.1 A, and Pb-free RoHS-compliant packaging.

Technical Context

The BD180G operates as a linear PNP power transistor in audio output stage configurations, supporting quasi-complementary push-pull topologies with its 80 V V_CEO rating and 1.0 A continuous collector current capability. Its f_T = 3.0 MHz enables stable gain in mid-frequency audio bandwidths without oscillation risk under proper biasing.

Thermal design relies on junction-to-case conduction via the TO-225 metal tab (pin 2/4 = collector), requiring mechanical mounting to heatsinks. Safe operating area is limited by secondary breakdown above 0.5 A at V_CE > 20 V in DC conditions, per Figure 1.

Key Specifications

Pinout & Package

BD180G uses the TO-225 package (Case 77-09, Style 1), with a metal tab electrically connected to the collector and mechanically mounted to heatsinks. Pin 1 is emitter, pin 2 and 4 are collector (dual-tab configuration), and pin 3 is base.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MJD180G and BD179, BD180G offers higher power dissipation (30 W vs. 20 W) and through-hole TO-225 mounting for robust mechanical and thermal attachment, making it preferred for prototyping, repair, and high-reliability linear audio applications where heatsink clamping is standard practice.

Availability

BD180G is available at Aetrix Electronics and suitable for Hi-Fi audio output stages, quasi-complementary amplifiers, and industrial linear regulator pass elements requiring stable component supply and long-lifecycle support.

Supply support for BD180G 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, sensor, and connectivity solutions for automotive, industrial, cloud, medical, and IoT applications.

The BD180G belongs to onsemi's legacy discrete power transistor family, engineered specifically for linear audio amplifier output stages and complementary driver applications where ruggedness, predictable gain, and thermal reliability are essential.

FAQ

What is the maximum continuous collector current for BD180G?

The BD180G has a maximum continuous collector current (I_C) of 1.0 A at T_C = 25 °C. Derating applies above 25 °C at 240 mW/°C. At elevated case temperatures, the usable I_C decreases linearly-for example, at T_C = 75 °C, max I_C drops to approximately 0.88 A. This rating assumes adequate heatsinking per the R_θJC = 4.16 °C/W specification. BD180G must not be operated beyond its SOA curve (Figure 1) to avoid secondary breakdown.

Is BD180G pin-compatible with BD179?

No, BD180G is not pin-compatible with BD179. While BD180G (PNP) and BD179 (NPN) are complementary devices sharing identical TO-225 package outlines and pin numbering (Style 1), their internal polarity differs: BD180G pin 1 = emitter, pins 2/4 = collector, pin 3 = base; BD179 pin 1 = collector, pins 2/4 = emitter, pin 3 = base. Swapping them without circuit revision causes immediate reverse-bias failure. BD180G and BD179 are intended for opposite sides of push-pull stages-not drop-in replacements.

What does the 'G' suffix mean in BD180G?

For BD180G, the 'G' suffix indicates a Pb-free (lead-free) and RoHS-compliant package per onsemi's standard marking convention. It confirms that the device meets EU RoHS Directive 2011/65/EU requirements, with lead content below 1000 ppm and no restricted substances above threshold limits. The 'G' does not denote a different die or electrical specification-the BD180G shares identical maximum ratings, electrical characteristics, and thermal performance with the legacy BD180, except for termination finish.

Can BD180G be used in switching applications?

BD180G can be used in low-frequency switching applications (<10 kHz) such as relay drivers or PWM-controlled linear regulators, provided V_CE(sat) ≤ 0.8 V and switching speed constraints are met. Its f_T = 3.0 MHz supports moderate edge rates, but storage time (not specified in the datasheet) and lack of optimized switching parameters make it less suitable than dedicated switching transistors like MJD127G. For hard-switching above 20 kHz, BD180G risks excessive switching losses and thermal runaway; consult SOA curves and ensure turn-off is actively accelerated.

What is the safe operating area (SOA) limitation for BD180G at DC operation?

At DC operation, BD180G's SOA is bounded by thermal and secondary breakdown limits. Per Figure 1, the DC boundary intersects ~0.3 A at V_CE = 100 V, ~0.15 A at V_CE = 50 V, and ~0.05 A at V_CE = 200 V. Exceeding these I_C–V_CE combinations risks instantaneous failure due to localized hot-spot formation. Designers must ensure the load line remains fully within the DC SOA envelope-including worst-case variations in supply voltage, signal swing, and thermal resistance-and apply derating for ambient temperature and heatsink performance. BD180G is not rated for avalanche operation.