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

STMicroelectronics BD136

Name: BD136
Brand: STMicroelectronics
SKU: BD136
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: BD136

Manufacturer:: STMicroelectronics

Category:: Single Bipolar Transistors

Package:: TO-225AA, TO-126-3

Datasheet:: BD136.pdf

Description:: TRANS PNP 45V 1.5A SOT-32-3

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:2,990

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

Product details

Overview

BD136 from STMicroelectronics is a complementary PNP bipolar junction transistor (BJT) in SOT-32 package, rated for -45 V V_CEO, -1.5 A I_C, and 12.5 W P_TOT at T_C ≤ 25 °C. It delivers h_FE = 25–250 at I_C = –150 mA, V_CE = –2 V, and is pre-selected for DC current gain consistency. It serves as output stage driver in quasi-complementary audio amplifier circuits.

For engineers reviewing the BD136 datasheet, BD136 pinout, BD136 application, or BD136 equivalent, key selection criteria include its PNP polarity, safe operating area under pulsed conditions, thermal resistance (R_thj-case = 10 °C/W), and h_FE grouping (e.g., BD136-16), especially when matching with BD135/NPN counterparts in push-pull stages.

Technical Context

The BD136 operates as a medium-power linear PNP BJT optimized for Class AB audio output stages. Its design supports complementary symmetry with BD135/BD139 NPN devices, featuring low V_CE(sat) (–0.5 V at I_C = –0.5 A, I_B = –0.05 A) and controlled h_FE spread across gain groups (63–250).

It uses epitaxial planar technology with ECOPACK® lead-free interconnect, rated for T_j up to 150 °C and storage from –65 to +150 °C. Absolute maximum ratings include –80 V V_CBO, –3 A I_CM, and R_thj-amb = 100 °C/W at ambient mounting.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	–45 V - Maximum collector-emitter voltage before breakdown under open-base condition; defines safe DC rail limit in amplifier output stage
I_C	–1.5 A - Continuous collector current rating; sets peak linear output capability in audio driver applications
P_TOT (T_C ≤ 25 °C)	12.5 W - Total power dissipation with heatsink; determines thermal design margin for TO-126-equivalent mounting
h_FE	25–250 - DC current gain range at I_C = –150 mA; enables predictable biasing and gain matching in complementary pairs
V_CE(sat)	–0.5 V @ I_C = –0.5 A - Low saturation voltage reduces conduction loss and improves efficiency in Class AB operation
R_thj-case	10 °C/W - Junction-to-case thermal resistance; informs heatsink interface design for reliable 12.5 W operation

Pinout & Package

BD136 is housed in the SOT-32 (TO-126-compatible) plastic package with standardized pin layout: emitter (pin 1), base (pin 2), collector (pin 3). The case is electrically connected to the collector terminal.

Pin/Terminal	Circuit Role	Design Meaning
1 (Emitter)	Current sink terminal for PNP device	Connected to load or output node; polarity inversion requires careful PCB routing in complementary designs
2 (Base)	Control input for minority-carrier injection	Driven by preceding stage; requires current-limiting resistor due to lack of integrated base protection
3 (Collector)	Main current output terminal	Internally tied to package tab; must be electrically isolated from heatsink unless common-collector configuration is intended

Key Features

Feature	Design Value
Pre-selected h_FE groups	BD136-16 offers h_FE = 100–160 at I_C = –150 mA, enabling matched pair assembly without binning
ECOPACK® compliance	Lead-free second-level interconnect per JEDEC JESD97; meets RoHS and halogen-free requirements for industrial production
High V_CBO rating	–80 V collector-base withstand supports operation with inductive flyback in relay drivers or transformer-coupled amplifiers
Low thermal resistance	R_thj-case = 10 °C/W allows 12.5 W dissipation with modest heatsinking-critical for compact audio module designs

Applications

Audio Power Amplifier Output Stage

Quasi-Complementary Driver

Use Scenario: Final push-pull output stage in 5–10 W stereo amplifier modules using discrete transistors.

IC Role / Device Role / Timing Role: PNP complement to BD135/NPN, delivering negative half-cycle current into speaker load.

Use Value: Matched h_FE and V_CE(sat) minimize crossover distortion; 12.5 W P_TOT supports sustained RMS output without thermal shutdown.

Use Scenario: Driver stage feeding power MOSFET gates in Class D amplifier half-bridges.

IC Role / Device Role / Timing Role: Medium-current PNP switch providing fast turn-off current path for gate discharge.

Use Value: –0.5 V V_CE(sat) ensures low-loss gate pull-down; –3 A I_CM handles transient gate charge demands.

DC Motor Speed Controller

Relay Interface Circuit

Use Scenario: H-bridge low-side driver controlling bidirectional 12 V DC motors in industrial actuators.

IC Role / Device Role / Timing Role: PNP switch sinking motor current during reverse polarity phase.

Use Value: –45 V V_CEO accommodates back-EMF spikes; R_thj-case = 10 °C/W enables continuous 1.5 A operation with minimal heatsink.

Use Scenario: Solid-state replacement for mechanical relay coils in PLC I/O modules.

IC Role / Device Role / Timing Role: High-voltage PNP switch driving inductive 24 V relay coils with snubberless operation.

Use Value: –80 V V_CBO withstands coil flyback without external clamp; pre-selected h_FE ensures consistent drive current across production lots.

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP medium-power BJT applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
BD140	Higher \|V_CEO\| = –80 V and \|V_CBO\| = –80 V; otherwise identical pinout, gain, and package	Suitable for higher-rail audio or industrial supplies where >45 V headroom is required	Select BD140 when operating above ±45 V rails; BD136 remains optimal for cost-sensitive ≤±45 V designs
MJD44H11	Different package (TO-252), higher I_C = –8 A, but lower h_FE min = 15 and no factory gain binning	Used in high-current switching rather than linear audio amplification	Choose only if board redesign permits SMD footprint change and application tolerates wider h_FE variation

Compared with BD140, BD136 trades off voltage headroom for tighter h_FE control and lower cost; versus MJD44H11, it prioritizes linear gain stability over raw current capacity-making BD136 the preferred choice for fidelity-critical audio output stages.

Availability

BD136 is available at Aetrix Electronics and suitable for audio power amplifiers, relay interface circuits, DC motor controllers, and quasi-complementary driver stages requiring stable component supply and consistent h_FE performance across production batches.

Supply support for BD136 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, digital, and mixed-signal ICs and discrete components for industrial, automotive, and consumer markets.

The BD136 belongs to ST's legacy bipolar transistor product line, engineered specifically for cost-effective, thermally robust linear amplification and switching in audio and industrial control systems.

FAQ

Is BD136 pin-compatible with BD140?

Yes, BD136 and BD140 share identical SOT-32 pinout (E-B-C), package dimensions, and thermal characteristics. They differ only in absolute maximum ratings: BD140 specifies –80 V V_CEO/V_CBO, while BD136 is rated at –45 V/–45 V. No PCB redesign is needed for substitution within voltage limits.

What does "BD136-16" marking indicate?

The "-16" suffix denotes a factory-selected h_FE group: 100–160 at I_C = –150 mA, V_CE = –2 V. This binning enables direct pairing with BD135-16 (NPN counterpart) to minimize gain mismatch in complementary amplifier stages without manual sorting.

Can BD136 be used in switching applications?

Yes-BD136 supports switching use cases such as relay drivers and motor controls, with I_CM = –3 A and V_CE(sat) = –0.5 V. However, its relatively slow f_T (~3 MHz, inferred from gain-bandwidth behavior in similar ST transistors) limits suitability for >100 kHz PWM; it is best applied below 50 kHz.

Does BD136 require a heatsink in typical operation?

A heatsink is required when dissipating >1.25 W continuously at ambient temperature (P_TOT derated per R_thj-amb = 100 °C/W). For 12.5 W operation, a heatsink with R_th ≤ 9.2 °C/W (including interface resistance) is mandatory to maintain T_j ≤ 150 °C with T_C ≤ 25 °C.

BD136 Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Series:: -

Package/Case:: TO-225AA, TO-126-3

Packaging:: Tube

Product Status:: Active

Transistor Type:: PNP

Current - Collector (Ic) (Max):: 1.5 A

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

Vce Saturation (Max) @ Ib, Ic:: 500mV @ 50mA, 500mA

Current - Collector Cutoff (Max):: 100nA (ICBO)

DC Current Gain (hFE) (Min) @ Ic, Vce:: 40 @ 2V, 150MA

Power - Max:: 1.25 W

Frequency - Transition:: -

Operating Temperature:: 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: SOT-32-3

BD136 FAQ

1.How can I place an order for BD136 through Aetrix?

Please submit a Request for Quotation (RFQ) for BD136 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 BD136 reliable?

The price and inventory of BD136 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BD136 is usually 5 days.

3.What payment methods are accepted for BD136?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BD136 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BD136?

BD136 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BD136 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 BD136?

For technical support, including BD136 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BD136 requirements.

6.How does Aetrix verify that BD136 is sourced from the original manufacturer or authorized distributors?

All BD136 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 BD136 meets industry standards.

7.What is the process for return or replacement of BD136?

All BD136 units undergo pre-shipment inspection (PSI). If there is an issue with BD136, 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 BD136 part is unused and in its original packaging.

Return procedure for BD136:

1.Submit a request within 90 days.

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

Tech Hub

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…

2026-08-21 What Is an LED Driver? Types, Circuits, Dimming, and Selection

An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…