onsemi BD436G

Overview

BD436G from onsemi is a plastic medium-power silicon PNP transistor rated for 32 V_CEO, 4.0 A collector current, and 36 W total device dissipation at T_C = 25°C, with DC current gain (h_FE) of 40–475 depending on operating conditions. It serves as a switching or linear amplifier in power supply control, motor drive stages, and relay drivers where robust PNP complementarity to BD437 is required.

For engineers reviewing the BD436G datasheet, pinout, applications, or equivalent options, key selection criteria include verified V_CEO/V_CBO = 32 V, guaranteed h_FE ≥ 40 at I_C = 10 mA, V_CE(sat) ≤ 0.5 V at I_C = 2.0 A/I_B = 0.2 A, thermal resistance R_θJC = 3.5 °C/W, and TO-225 package compatibility with industrial PCB layouts.

Technical Context

The BD436G operates as a discrete PNP bipolar junction transistor with fixed emitter-base and collector-base junction structures optimized for medium-power linear and saturated switching. Its safe operating area (SOA) is defined up to 150°C junction temperature, with secondary breakdown limits validated for DC and pulsed operation per Figure 4.

It features complementary pairing with BD437 (NPN), enabling push-pull and Class-B amplifier topologies. Electrical characteristics are specified at T_C = 25°C, with derating applied above that temperature per its 288 mW/°C thermal slope.

Key Specifications

Pinout & Package

BD436G is housed in a TO-225 package (Case 77-09, Style 1), featuring a 3-pin configuration with pin 4 internally connected to the collector and electrically tied to the metal tab (backside). The package is Pb-free and RoHS compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BD438G, the BD436G offers tighter voltage margin at lower cost and identical thermal performance in TO-225; versus MJD44H11G, BD436G provides through-hole reliability and proven legacy design support but requires different board layout and lacks SMT scalability.

Availability

BD436G is available at Aetrix Electronics and suitable for power supply regulation, DC motor control, and relay driver applications requiring stable component supply, long-term industrial availability, and RoHS-compliant manufacturing.

Supply support for BD436G 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 BD436G belongs to onsemi's legacy medium-power discrete transistor family, designed specifically for cost-sensitive industrial and power conversion applications demanding ruggedness, thermal stability, and complementary NPN/PNP pairing.

FAQ

What is the maximum continuous collector current rating for BD436G?

The BD436G has a maximum continuous collector current (I_C) rating of 4.0 A at T_C = 25°C. In real-world designs, sustained current must be reduced based on thermal derating - for example, at T_C = 75°C, usable I_C drops to approximately 2.5 A due to the 288 mW/°C derating slope and power dissipation limits. Always verify junction temperature using R_θJC = 3.5 °C/W in your thermal model.

Is BD436G pin-compatible with BD438G?

Yes, BD436G is pin-compatible with BD438G - both use the TO-225 package (Case 77-09, Style 1) with identical pin 1 (emitter), pins 2 & 4 (collector), and pin 3 (base) assignments. The only functional difference is V_CEO/V_CBO rating (32 V vs. 45 V); all other electrical and mechanical specifications match, allowing direct substitution where voltage margin permits.

Does BD436G require a heatsink in typical switching applications?

BD436G requires a heatsink when dissipating more than ~5 W continuously - for example, in linear regulator or high-duty-cycle PWM applications. At I_C = 2.0 A and V_CE(sat) = 0.5 V, conduction loss alone is 1.0 W, but switching losses and ambient temperature may necessitate heatsinking. With R_θJC = 3.5 °C/W and a 20°C/W heatsink, junction temperature stays within 150°C limit up to ~12 W total dissipation.

What is the guaranteed DC current gain (h_FE) of BD436G at I_C = 500 mA?

The BD436G guarantees h_FE ≥ 85 at I_C = 500 mA, V_CE = 1.0 V, and T_C = 25°C. This high mid-current gain ensures reliable saturation with modest base drive - for instance, only ~5.9 mA I_B is needed to fully turn on BD436G at 500 mA collector current, easing microcontroller GPIO or op-amp driver design.

Can BD436G be used as a direct replacement for BD436 in legacy designs?

Yes, BD436G is the Pb-free, RoHS-compliant version of the legacy BD436, sharing identical electrical specifications, TO-225 package dimensions, and pinout. The "G" suffix denotes green packaging; no circuit redesign or layout change is required when upgrading from BD436 to BD436G, provided lead-free soldering processes are used.