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Diodes Incorporated BC858B-7-F
- Part No.:
- BC858B-7-F
- Manufacturer:
- Diodes Incorporated
- Category:
- Single Bipolar Transistors
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
BC858B-7-F.pdf
- Description:
- TRANS PNP 30V 0.1A SOT-23-3
- Quantity:
- Payment:
- Shipping:
Inventory:2,850
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Product details
Overview
BC858B-7-F from Diodes Incorporated is a PNP small-signal transistor in SOT23 package, rated for VCEO = −30 V, IC = −100 mA, and hFE = 220–475 at IC = −2 mA. It delivers VCE(sat) ≤ −300 mV at IC = −10 mA / IB = −0.5 mA and operates across −55°C to +150°C, supporting switching and audio-frequency amplifier functions in compact consumer and industrial PCBs.
For engineers reviewing the BC858B-7-F datasheet, BC858B-7-F pinout, BC858B-7-F application, or BC858B-7-F equivalent, key selection criteria include guaranteed hFE binning (B-grade), JEDEC-qualified reliability, RoHS/"Green" compliance, and SOT23 thermal performance with RθJA = 403°C/W on minimal pad layout.
Technical Context
This PNP bipolar junction transistor uses epitaxial planar die construction with base-emitter and collector-base junctions optimized for low saturation voltage and stable DC current gain across temperature. Its fT ≥ 100 MHz supports AF amplification up to mid-audio range, while ESD ratings of 4 kV HBM ensure robustness during handling and board assembly.
The device is characterized under pulsed conditions (≤300 µs, ≤2% duty cycle) for VCE(sat), VBE(on), and hFE, and its safe operating area is defined by VCEO = −30 V, IC = −100 mA, and PD = 310 mW at TA = +25°C on standard FR-4.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | −30 V - Maximum allowable collector-emitter voltage before breakdown; defines upper rail limit in PNP switch or amplifier stages. |
| IC (cont.) | −100 mA - Continuous collector current rating; sets maximum load drive capability in linear or saturated operation. |
| hFE @ IC = −2 mA | 220–475 - B-grade DC current gain range; ensures predictable base drive requirements for biasing and switching control. |
| VCE(sat) | ≤ −300 mV @ IC = −10 mA / IB = −0.5 mA - Low saturation voltage minimizes power loss and heat generation in switching applications. |
| fT | ≥ 100 MHz - Gain-bandwidth product enabling stable small-signal amplification up to ~100 kHz with adequate gain margin. |
| RθJA | 403 °C/W - Junction-to-ambient thermal resistance on minimal 1 oz copper; informs derating needed for sustained power dissipation. |
| ESD HBM | 4,000 V - Human Body Model rating; confirms suitability for manual handling and non-ESD-controlled assembly environments. |
Pinout & Package
BC858B-7-F is housed in a surface-mount SOT23 (TO-236AB) plastic package with matte tin-plated leads, UL 94V-0 flammability rating, and moisture sensitivity level 1 per J-STD-020. Weight is approximately 0.008 g.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| E (Emitter) | Current source terminal for PNP operation | Connected to higher potential rail; base-emitter forward bias initiates conduction. |
| B (Base) | Control input for minority-carrier injection | Receives negative-going drive signal relative to emitter to turn on transistor. |
| C (Collector) | Current sink terminal | Delivers controlled current to load tied between collector and ground or lower-potential node. |
Key Features
| Feature | Design Value |
|---|---|
| JEDEC-qualified reliability | Qualified to AEC-Q standards for high-reliability applications including industrial and automotive-adjacent systems. |
| RoHS & "Green" compliant | Lead-free, halogen-free (<900 ppm Br/Cl, <1000 ppm Sb), fully compliant with EU RoHS 2015/863/EU. |
| SOT23 automatic insertion compatibility | Standardized footprint and lead geometry support high-speed pick-and-place and reflow soldering without modification. |
| Low VCE(sat) at moderate current | −300 mV max at IC = −10 mA enables efficient switching in battery-powered and thermally constrained designs. |
| Wide operating temperature | −55°C to +150°C junction range supports deployment in extended-environment applications such as motor controls and outdoor electronics. |
Applications
| LED Driver Circuit | Level-Shifting Interface |
|---|---|
|
Use Scenario: Driving discrete indicator LEDs from microcontroller GPIO pins with active-low logic. IC Role / Device Role / Timing Role: PNP switch controlling current path from VCC to LED anode; emitter tied to supply, collector to LED cathode. Use Value: VCE(sat) ≤ −300 mV ensures >95% efficiency in 3.3 V or 5 V LED circuits with 10–20 mA loads. |
Use Scenario: Translating 1.8 V logic outputs to 3.3 V or 5 V domains in mixed-voltage digital subsystems. IC Role / Device Role / Timing Role: Active-low level shifter using common-emitter configuration with pull-up on collector. Use Value: hFE ≥ 220 guarantees clean edge transitions and sub-100 ns propagation delay at 1 MHz toggle rates. |
| Audio Preamp Stage | Power Supply Enable Switch |
|
Use Scenario: Low-noise voltage amplification in microphone preamplifier front-ends or tone-control networks. IC Role / Device Role / Timing Role: Common-emitter small-signal amplifier biased at IC = −2 mA with emitter degeneration. Use Value: NF ≤ 10 dB at 1 kHz and fT ≥ 100 MHz support high-fidelity gain up to 20 kHz with minimal distortion. |
Use Scenario: Enabling/disabling downstream 3.3 V or 5 V rails via microcontroller output in power management subsystems. IC Role / Device Role / Timing Role: High-side switch controlling PMOS gate drive or LDO enable input. Use Value: VCEO = −30 V and IC = −100 mA allow direct control of loads up to 100 mA with no external driver stage. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP small-signal transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BC857B-7-F | VCEO = −45 V, VCE(sat) ≤ −250 mV @ same test condition; otherwise identical hFE bin and SOT23 footprint. | Supports higher supply rails (up to 45 V) but same thermal and switching performance. | Select when system VCC exceeds 30 V and tighter VCE(sat) is required. |
| MMBT3906 | hFE = 100–300 (unbinned), VCEO = −40 V, RθJA = 450°C/W; JEDEC-standard but not AEC-Q qualified. | Lacks guaranteed hFE binning and automotive qualification; suitable for cost-sensitive commercial use only. | Choose for non-critical, high-volume consumer applications where qualification and gain consistency are secondary. |
Compared with BC857B-7-F and MMBT3906, BC858B-7-F offers optimal balance of 30 V rail compatibility, guaranteed B-grade hFE, and AEC-Q alignment-making it preferred for industrial control and long-lifecycle embedded systems where parameter stability matters.
Availability
BC858B-7-F is available at Aetrix Electronics and suitable for LED driver circuits, level-shifting interfaces, and audio preamp stages requiring stable component supply, consistent hFE binning, and extended-temperature operation.
Supply support for BC858B-7-F 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
Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability components for industrial, computing, and consumer markets.
BC858B-7-F belongs to the BC856A–BC858C PNP transistor family, designed specifically for automated assembly, switching, and AF amplification in space-constrained, thermally demanding applications.
FAQ
What is the marking code for BC858B-7-F on the SOT23 package?
The top-side laser marking for BC858B-7-F is "K3B", as confirmed in the Diodes Incorporated ordering information table. This 3-character code identifies the device type and gain bin (B-grade), and is visible under 20× magnification on the molded plastic body.
Is BC858B-7-F suitable for automotive applications?
BC858B-7-F itself is not automotive-qualified; Diodes offers separate Q-grade variants (e.g., BC857BQ) under distinct part numbers and datasheets. While BC858B-7-F meets JEDEC reliability standards and operates from −55°C to +150°C, it lacks AEC-Q200 stress testing documentation required for automotive use.
How does BC858B-7-F differ from BC856B-7-F electrically?
BC858B-7-F has lower voltage ratings: VCEO = −30 V and VCBO = −30 V versus −65 V and −80 V for BC856B-7-F. All other parameters-including hFE range, VCE(sat), fT, and package-are identical. The BC858 series trades voltage headroom for optimized performance at lower supply rails.
Can BC858B-7-F be used in linear regulator pass transistor roles?
No-BC858B-7-F is not rated for continuous linear regulation due to limited power dissipation (310 mW) and absence of Safe Operating Area (SOA) data for DC bias conditions. Its SOA curve is defined only for single-pulse operation; sustained linear use risks thermal runaway above ~50 mW.
BC858B-7-F Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Transistor Type:
- PNP
- Current - Collector (Ic) (Max):
- 100 mA
- Voltage - Collector Emitter Breakdown (Max):
- 30 V
- Vce Saturation (Max) @ Ib, Ic:
- 650mV @ 5mA, 100mA
- Current - Collector Cutoff (Max):
- 15nA
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 220 @ 2mA, 5V
- Power - Max:
- 300 mW
- Frequency - Transition:
- 200MHz
- Operating Temperature:
- -65°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
BC858B-7-F FAQ
1.How can I place an order for BC858B-7-F through Aetrix?
Please submit a Request for Quotation (RFQ) for BC858B-7-F 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 BC858B-7-F reliable?
The price and inventory of BC858B-7-F are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC858B-7-F is usually 5 days.
3.What payment methods are accepted for BC858B-7-F?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC858B-7-F transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC858B-7-F?
BC858B-7-F orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC858B-7-F 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 BC858B-7-F?
For technical support, including BC858B-7-F datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC858B-7-F requirements.
6.How does Aetrix verify that BC858B-7-F is sourced from the original manufacturer or authorized distributors?
All BC858B-7-F 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 BC858B-7-F meets industry standards.
7.What is the process for return or replacement of BC858B-7-F?
All BC858B-7-F units undergo pre-shipment inspection (PSI). If there is an issue with BC858B-7-F, 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 BC858B-7-F part is unused and in its original packaging.
Return procedure for BC858B-7-F:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC858B-7-F Tags
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MMBT3906LT1G
onsemi
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Diodes Incorporated
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MMBT3904LT1G
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MMBT3906-7-F
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MMBT3904-TP
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onsemi
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BC847B,215
Nexperia USA Inc.
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MMBTA06LT1G
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