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onsemi BC81740NMMTF
- Part No.:
- BC81740NMMTF
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
BC81740NMMTF.pdf
- Description:
- TRANS NPN 45V 0.8A SOT-23-3
- Quantity:
- Payment:
- Shipping:
Inventory:5,164
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Product details
Overview
BC81740NMMTF from ON Semiconductor is an NPN epitaxial silicon transistor in SOT-23 package, rated for 45 V VCEO, 800 mA IC, and hFE of 250–630 at IC = 100 mA. It serves as a general-purpose switching and amplification device in low-power analog and digital signal paths, including AF driver stages and low-power output stages.
For engineers reviewing the BC81740NMMTF datasheet, pinout, applications, or equivalent options, key selection criteria include verified hFE classification (40), VCE(sat) ≤ 0.7 V at 500 mA/50 mA drive, thermal resistance of 403 °C/W, and SOT-23 footprint compatibility with standard PCB land patterns.
Technical Context
This transistor operates as a discrete bipolar junction device with epitaxial base construction, optimized for linear amplification and saturated switching. Its DC current gain is binned to hFE = 250–630 (hFE1) and ≥170 (hFE2 at 300 mA), and it maintains stable VBE(on) = 1.2 V at IC = 300 mA.
Thermal performance is defined by RθJA = 403 °C/W on FR-4 PCB (76 mm × 114 mm, minimum land pattern), with power dissipation derated at 2.48 mW/°C above 25 °C. Absolute maximum ratings include VCBO = 50 V, TJ = 150 °C, and storage range of –65 to +150 °C.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 45 V - Maximum collector-emitter voltage before breakdown under open-base conditions; defines safe operating voltage in common-emitter switch configurations. |
| IC (DC) | 800 mA - Continuous collector current rating; supports load switching up to ~700 mA with adequate heatsinking and derating. |
| hFE (Class 40) | 250–630 - Guaranteed DC current gain range at VCE = 1 V, IC = 100 mA; enables predictable base drive sizing for saturation. |
| VCE(sat) | 0.7 V max at IC = 500 mA, IB = 50 mA - Low saturation voltage minimizes conduction loss in switching applications. |
| fT | 100 MHz - Current-gain bandwidth product at VCE = 5 V, IC = 10 mA; supports audio-frequency amplification and fast digital switching. |
| RθJA | 403 °C/W - Junction-to-ambient thermal resistance on standard FR-4 board; determines temperature rise under given power dissipation. |
Pinout & Package
SOT-23 (TO-236AB) 3-lead plastic surface-mount package with gull-wing leads; standardized footprint per JEDEC MO-178AB. Dimensions: 2.92 ± 0.20 mm length, 1.30+0.20−0.15 mm width, 1.20 mm max height.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Base) | Control terminal for minority-carrier injection | Receives forward-biased current to modulate collector current; requires current-limiting resistor in most driver circuits. |
| 2 (Emitter) | Source of majority carriers (electrons) | Common reference node in common-emitter configuration; tied to ground or low-impedance return path. |
| 3 (Collector) | Output current terminal | Delivers amplified/saturated current to load; connected to supply rail via load in switching topologies. |
Key Features
| Feature | Design Value |
|---|---|
| hFE classification "40" | Guaranteed 250–630 gain range ensures consistent base drive requirements across production lots. |
| Low VCE(sat) | ≤ 0.7 V at 500 mA enables <100 mW conduction loss in typical 5 V logic-level switching. |
| Complementary pairing | Designed as NPN counterpart to BC807/BC808 PNP transistors for push-pull and differential amplifier designs. |
| JEDEC-standard SOT-23 | Enables automated placement and reflow compatibility with industry-standard pick-and-place equipment and solder profiles. |
Applications
| Audio Pre-Amplifier Stage | Microcontroller GPIO Driver |
|---|---|
|
Use Scenario: Amplifying weak line-level signals (≤100 mV) before ADC sampling in portable audio recorders. IC Role / Device Role / Timing Role: Linear small-signal amplifier with fixed bias network; operates in active region with VCE ≈ 3–5 V. Use Value: High hFE (250–630) reduces required base current, minimizing loading on preceding stage; fT = 100 MHz ensures flat response up to 20 kHz. |
Use Scenario: Driving LED indicators or small relays from 3.3 V or 5 V microcontroller outputs. IC Role / Device Role / Timing Role: Digital switch in common-emitter configuration; biased into saturation with IB/IC ≥ 10. Use Value: VCE(sat) ≤ 0.7 V limits power loss to <350 mW at 500 mA, enabling reliable operation without external heat sinking. |
| Low-Power Output Stage | AF Driver for Small Speakers |
|
Use Scenario: Final gain stage in battery-powered intercoms delivering ≤100 mW to 8 Ω loads. IC Role / Device Role / Timing Role: Class-A or class-AB emitter-follower or common-emitter amplifier with emitter degeneration. Use Value: VCEO = 45 V headroom accommodates 12 V supply rails with transient margin; low Cob = 12 pF avoids high-frequency instability. |
Use Scenario: Driving 0.5 W, 8 Ω miniature speakers in handheld medical devices. IC Role / Device Role / Timing Role: Voltage-controlled current source in single-ended output topology with DC-coupled input. Use Value: Verified hFE binning ensures consistent gain matching across units; TJ ≤ 150 °C rating supports sealed enclosure operation. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar NPN general-purpose transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BC817-40LT1G | Same hFE bin (250–630), identical SOT-23 package, but manufactured by ON Semiconductor post-Fairchild integration; marking "8FC" vs "40". | No functional difference; fully interchangeable in all documented BC817-40 use cases. | Select BC817-40LT1G when sourcing from ON Semiconductor's current production line with updated nomenclature compliance. |
| MMBT3904LT1G | Lower hFE (100–300), same VCEO = 40 V, lower IC = 200 mA, higher VCE(sat) = 0.3 V typical at 10 mA. | Not suitable for >200 mA switching or high-gain amplification; limited to low-current signal routing and logic interface. | Choose MMBT3904LT1G only for low-power, cost-sensitive designs where gain and current capability are secondary to footprint and availability. |
Compared with BC81740NMMTF, BC817-40LT1G offers identical electrical and mechanical specifications with updated branding, while MMBT3904LT1G trades gain and current capacity for broader distribution and lower unit cost in sub-200 mA roles.
Availability
BC81740NMMTF is available at Aetrix Electronics and suitable for audio pre-amplifier stages, microcontroller GPIO drivers, and low-power output stages requiring stable component supply, consistent hFE binning, and JEDEC-compliant SOT-23 packaging.
Supply support for BC81740NMMTF 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
ON Semiconductor is a global semiconductor manufacturer specializing in energy-efficient power management, analog, sensors, and discrete components for automotive, industrial, cloud, and consumer markets.
The BC81740NMMTF belongs to ON Semiconductor's legacy general-purpose bipolar transistor product line, originally developed by Fairchild and maintained for cost-sensitive, high-volume linear and switching applications requiring proven reliability and broad design support.
FAQ
What is the hFE range guaranteed for BC81740NMMTF?
The BC81740NMMTF is binned to hFE = 250–630 at VCE = 1 V and IC = 100 mA (hFE1), and ≥170 at IC = 300 mA (hFE2). This classification ("40") is laser-marked as "8FC" on the device body and confirmed in the official ON Semiconductor datasheet revision 1.1.0.
Is BC81740NMMTF pin-compatible with BC817-40LT1G?
Yes, BC81740NMMTF is mechanically and electrically pin-compatible with BC817-40LT1G: both use SOT-23 package with identical pinout (1=Base, 2=Emitter, 3=Collector), same absolute maximum ratings, and overlapping electrical characteristics. The difference lies only in branding and manufacturing lineage post-Fairchild integration.
What is the maximum continuous collector current for BC81740NMMTF?
The BC81740NMMTF is rated for IC = 800 mA DC under recommended operating conditions. Derating applies above 25 °C ambient: power dissipation must be reduced by 2.48 mW per °C, limiting usable current in high-temperature environments unless board-level thermal management is enhanced.
Does BC81740NMMTF support switching applications up to 100 kHz?
Yes, BC81740NMMTF supports switching applications up to at least 100 kHz due to its fT = 100 MHz and low Cob = 12 pF. Switching speed is further enabled by VCE(sat) ≤ 0.7 V at 500 mA/50 mA drive, ensuring fast turn-on/turn-off with appropriate base drive circuitry.
What is the thermal resistance (RθJA) of BC81740NMMTF on a standard PCB?
The BC81740NMMTF has RθJA = 403 °C/W when mounted on a standard FR-4 PCB measuring 76 mm × 114 mm × 1.57 mm with minimum land pattern. This value assumes no additional copper pour or thermal vias; adding thermal relief or copper area reduces effective RθJA in practice.
BC81740NMMTF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Transistor Type:
- NPN
- Current - Collector (Ic) (Max):
- 800 mA
- Voltage - Collector Emitter Breakdown (Max):
- 45 V
- Vce Saturation (Max) @ Ib, Ic:
- 700mV @ 50mA, 500mA
- Current - Collector Cutoff (Max):
- 100nA
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 250 @ 100mA, 1V
- Power - Max:
- 310 mW
- Frequency - Transition:
- 100MHz
- Operating Temperature:
- 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
BC81740NMMTF FAQ
1.How can I place an order for BC81740NMMTF through Aetrix?
Please submit a Request for Quotation (RFQ) for BC81740NMMTF 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 BC81740NMMTF reliable?
The price and inventory of BC81740NMMTF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC81740NMMTF is usually 5 days.
3.What payment methods are accepted for BC81740NMMTF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC81740NMMTF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC81740NMMTF?
BC81740NMMTF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC81740NMMTF 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 BC81740NMMTF?
For technical support, including BC81740NMMTF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC81740NMMTF requirements.
6.How does Aetrix verify that BC81740NMMTF is sourced from the original manufacturer or authorized distributors?
All BC81740NMMTF 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 BC81740NMMTF meets industry standards.
7.What is the process for return or replacement of BC81740NMMTF?
All BC81740NMMTF units undergo pre-shipment inspection (PSI). If there is an issue with BC81740NMMTF, 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 BC81740NMMTF part is unused and in its original packaging.
Return procedure for BC81740NMMTF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC81740NMMTF Tags
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