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 BC107

Name: BC107
Brand: STMicroelectronics
SKU: BC107
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: BC107

Manufacturer:: STMicroelectronics

Category:: Single Bipolar Transistors

Package:: TO-206AA, TO-18-3 Metal Can

Datasheet:: BC107.pdf

Description:: TRANS NPN 45V 0.1A TO-18

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:2,952

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

Product details

Overview

BC107 from STMicroelectronics is a silicon planar epitaxial NPN bipolar junction transistor in TO-18 metal package, designed for low-noise audio amplifier input stages and driver applications. It delivers h_FE = 110–450 (BC107/BC107B), V_CEO = 45 V, I_C = 100 mA, and NF = 2–10 dB at 1 kHz with 200 Hz bandwidth - used in TV receiver signal processing and preamplifier circuits.

For engineers reviewing the BC107 datasheet, BC107 pinout, BC107 application, or BC107 equivalent, key selection criteria include noise figure under 2 mA bias, DC current gain spread across variants, thermal resistance (R_thj-case = 200 °C/W), TO-18 mechanical compatibility, and complementary pairing with BC177/BC177B for push-pull audio stages.

Technical Context

The BC107 operates as a general-purpose low-noise NPN BJT optimized for linear amplification in analog signal chains. Its design emphasizes low base-emitter saturation voltage (V_BE(sat) = 750–950 mV), high small-signal current gain (h_fe = 250–300 at 1 kHz), and controlled junction capacitance (C_CB = 4–6 pF, C_EB = 12 pF) to support stable audio-frequency operation up to 100 MHz f_T.

It features a maximum junction temperature of 175 °C and thermal resistance of 200 °C/W (junction-to-case), enabling reliable operation in compact TO-18 metal-can packages without forced cooling. Absolute ratings include V_CBO = 50 V, V_EBO = 6 V, and P_tot = 0.3 W at T_amb ≤ 25 °C.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	45 V - supports rail voltages up to ±22.5 V in Class-A audio stages without breakdown
h_FE	110–450 - wide DC gain range enables bias point flexibility in discrete amplifier designs
NF	2–10 dB @ 1 kHz - low noise performance critical for microphone preamp and tuner IF stages
C_CB	4–6 pF - limits high-frequency roll-off and ensures stability in feedback amplifier topologies
R_thj-case	200 °C/W - allows direct mounting to heatsinks in TO-18-compatible fixtures for thermal management
I_C	100 mA - sufficient for line-level driver and intermediate gain stage current demands

Pinout & Package

BC107 is housed in a hermetically sealed TO-18 metal can package with three axial leads: Emitter (shortest lead), Base (center), Collector (longest lead, case-connected). The metal case serves as the collector terminal and provides electromagnetic shielding.

Pin/Terminal	Circuit Role	Design Meaning
Emitter (E)	Current output terminal	Shortest lead; connects to ground or emitter resistor for bias stabilization
Base (B)	Control input terminal	Center lead; accepts low-current drive for linear amplification or switching
Collector (C)	Current input terminal	Longest lead; electrically tied to metal case for heat sinking and EMI reduction

Key Features

Feature	Design Value
Low-noise amplification	NF = 2 dB min at 0.2 mA, enabling high-SNR audio front-ends
High DC current gain	h_FE ≥ 110 at 2 mA ensures stable bias in resistor-loaded CE stages
TO-18 metal-can shielding	Hermetic seal and conductive case suppress RF interference in sensitive analog paths
Complementary pairing	Matched with BC177/BC177B for push-pull output stages in discrete audio amps

Applications

TV Receiver IF Amplifier

Microphone Preamplifier

Use Scenario: Amplifies intermediate frequency signals (45.75 MHz) after mixer stage in analog TV tuners.

IC Role / Device Role / Timing Role: NPN BJT configured in common-emitter topology for 20–30 dB voltage gain with minimal added noise.

Use Value: NF ≤ 10 dB ensures preserved SNR in weak-signal reception; h_fe > 250 maintains gain stability across temperature.

Use Scenario: First-stage amplification of electret microphone output (1–10 mV) before ADC or tone control.

IC Role / Device Role / Timing Role: Low-bias, low-noise NPN amplifier biased at 0.2 mA for optimal noise performance.

Use Value: 2 dB NF at 200 Hz–20 kHz band enables clean voice capture without active cooling or complex compensation.

Audio Tone Control Driver

Discrete Op-Amp Input Stage

Use Scenario: Drives passive Baxandall tone stack (bass/treble controls) in analog hi-fi preamps.

IC Role / Device Role / Timing Role: Common-collector (emitter-follower) buffer with high input impedance and low output Z.

Use Value: h_ie = 4–4.8 kΩ and low V_CE(sat) (70–250 mV) prevent loading of RC networks and preserve frequency response.

Use Scenario: Input differential pair in discrete op-amp designs requiring matched gain and offset.

IC Role / Device Role / Timing Role: NPN transistor in long-tailed pair configuration with BC177 complement for balanced inputs.

Use Value: Tight h_FE spread (BC107B: 200–450) and low C_CB reduce input offset drift and improve CMRR above 10 kHz.

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-noise NPN BJT amplifier applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
BC547	Plastic TO-92 package; h_FE = 110–800; NF ≈ 10 dB; R_thj-amb = 200 °C/W	No metal-can shielding; lower thermal robustness; unsuitable for EMI-sensitive IF stages	Preferred for cost-sensitive consumer audio where RF immunity is not critical
2N3904	TO-92; V_CEO = 40 V; h_FE = 100–300; NF = 5 dB @ 1 kHz; C_CB = 4 pF	Lower V_CEO limits supply headroom; identical noise but no case-grounded collector	Used in general-purpose amplifiers where TO-18 mechanical fit and shielding are unnecessary

Compared with BC547 and 2N3904, BC107 offers superior EMI shielding via TO-18 metal case, tighter thermal resistance control, and guaranteed low-noise performance down to 200 Hz - making it preferred for broadcast-grade analog signal conditioning where layout constraints prevent external shielding.

Availability

BC107 is available at Aetrix Electronics and suitable for TV receiver IF amplifiers, microphone preamplifiers, audio tone control drivers, and discrete op-amp input stages requiring stable component supply and legacy through-hole compatibility.

Supply support for BC107 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, designing and manufacturing analog, digital, and mixed-signal ICs and discrete components for industrial, automotive, and consumer markets.

The BC107 belongs to ST's legacy bipolar transistor product line, engineered specifically for high-fidelity analog signal amplification in broadcast and professional audio equipment where reliability, noise performance, and thermal stability are critical.

FAQ

Is BC107 pin-compatible with BC108 or BC109?

No. While all share TO-18 packaging and NPN polarity, BC108/BC109 have higher V_CEO (20 V/25 V) and lower h_FE ranges (110–800), and differ in noise figure and capacitance. Direct substitution requires verification of gain, voltage rating, and noise requirements per circuit node.

Can BC107 be used in switching applications?

Yes, but not optimally. Its relatively slow transition frequency (f_T ≈ 100 MHz) and moderate h_fe make it viable for low-speed (<100 kHz) switching, yet its primary design intent is linear amplification. For switching, dedicated fast-switching transistors like BC337 offer better saturation characteristics.

What is the significance of the 'B' suffix in BC107B?

The 'B' denotes an enhanced version with higher minimum h_FE (200 vs. 110 for BC107) and extended h_FE range (200–450), achieved via tighter process control. It also specifies improved noise figure consistency and is recommended for designs requiring guaranteed gain margin in production.

Does BC107 require derating above 25°C ambient?

Yes. With R_thj-amb = 500 °C/W, power dissipation must be linearly reduced above 25°C. At 70°C ambient, P_tot drops to 0.195 W. Derating curves in the datasheet show safe operating area boundaries - critical when used in enclosed chassis or stacked PCB assemblies.

BC107 Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Series:: -

Package/Case:: TO-206AA, TO-18-3 Metal Can

Packaging:: Tube

Product Status:: Obsolete

Transistor Type:: NPN

Current - Collector (Ic) (Max):: 100 mA

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

Vce Saturation (Max) @ Ib, Ic:: 600mV @ 5mA, 100mA

Current - Collector Cutoff (Max):: 15nA (ICBO)

DC Current Gain (hFE) (Min) @ Ic, Vce:: 110 @ 2mA, 5V

Power - Max:: 300 mW

Frequency - Transition:: -

Operating Temperature:: 175°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-18

BC107 FAQ

1.How can I place an order for BC107 through Aetrix?

Please submit a Request for Quotation (RFQ) for BC107 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 BC107 reliable?

The price and inventory of BC107 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC107 is usually 5 days.

3.What payment methods are accepted for BC107?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC107 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BC107?

BC107 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BC107 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 BC107?

For technical support, including BC107 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC107 requirements.

6.How does Aetrix verify that BC107 is sourced from the original manufacturer or authorized distributors?

All BC107 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 BC107 meets industry standards.

7.What is the process for return or replacement of BC107?

All BC107 units undergo pre-shipment inspection (PSI). If there is an issue with BC107, 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 BC107 part is unused and in its original packaging.

Return procedure for BC107:

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…