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onsemi KST3906MTF
- Part No.:
- KST3906MTF
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
KST3906MTF.pdf
- Description:
- TRANS PNP 40V 0.2A SOT-23-3
- Quantity:
- Payment:
- Shipping:
Inventory:7,877
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Product details
Overview
KST3906MTF from ON Semiconductor is a PNP epitaxial silicon transistor in SOT-23 package, rated for -40 V collector-emitter voltage, -200 mA continuous collector current, and 350 mW power dissipation. It delivers DC current gain (hFE) of 60–300 across 0.1–100 mA IC range and supports switching applications requiring <70 ns turn-on and <300 ns turn-off times, such as low-voltage level shifting in portable power management circuits.
For engineers reviewing the KST3906MTF datasheet, pinout, applications, or equivalent options, key selection criteria include verified PNP polarity, SOT-23 footprint compatibility, guaranteed hFE ≥60 at IC = -10 mA, and saturation voltage ≤-0.25 V at IC = -10 mA/IB = -1 mA - all confirmed per Fairchild/ON Semiconductor Rev. A3 specification.
Technical Context
This discrete PNP bipolar junction transistor operates in active, saturation, and cutoff regions with defined breakdown limits: VCBO = -40 V, VCEO = -40 V, and VEBO = -5 V. Its fT = 250 MHz at IC = -10 mA/VCE = -20 V enables use in RF-coupled preamplifier stages up to ~100 MHz.
Thermal performance is characterized by TSTG = -55°C to +150°C storage range and specified Cob = 4.5 pF at VCB = -5 V, supporting stable high-frequency bias networks. Noise figure is 4 dB at IC = -100 μA/VCE = -5 V/RS = 1 kΩ, suitable for low-noise analog front-end designs.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Device Type | PNP bipolar junction transistor - provides current sinking capability in emitter-follower or common-emitter switch configurations |
| VCEO | -40 V - maximum allowable collector-emitter voltage before avalanche breakdown under open-base conditions |
| IC(max) | -200 mA - absolute maximum continuous collector current without thermal derating at Ta = 25°C |
| hFE @ IC = -10 mA | 100 - minimum DC current gain ensures reliable base drive margin for switching loads up to 10 mA |
| VCE(sat) @ IC/IB = -10 mA/-1 mA | -0.25 V - low saturation voltage minimizes conduction loss in battery-powered load switches |
| fT | 250 MHz - usable bandwidth limit for small-signal amplification or RF coupling below 100 MHz |
| Cob | 4.5 pF - output capacitance impacts high-frequency stability and rise/fall time in switching nodes |
Pinout & Package
SOT-23 plastic surface-mount package with 3-pin configuration, 1.30 mm × 0.95 mm footprint, and 0.95 mm height. Pin 1 = Base, Pin 2 = Emitter, Pin 3 = Collector - standard orientation per JEDEC TO-236AB.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Base) | Control input terminal | Receives forward-biased current to enable conduction between emitter and collector; requires series resistor for current limiting |
| 2 (Emitter) | Current source node | Connected to higher potential rail in PNP switch; carries full load current when device is saturated |
| 3 (Collector) | Output current path | Drains current to load or ground; voltage swing limited by VCEO rating and PCB trace inductance |
Key Features
| Feature | Design Value |
|---|---|
| DC current gain range | hFE = 60–300 across IC = 0.1–100 mA - enables consistent biasing across production batches and temperature |
| Low VCE(sat) | -0.25 V at IC = -10 mA/IB = -1 mA - reduces power loss in always-on bias networks and LED drivers |
| High fT | 250 MHz - supports signal amplification and fast switching in audio preamp and pulse generator circuits |
| Low noise figure | 4 dB at 10 Hz–15.7 kHz - suitable for microphone biasing and low-level analog signal conditioning |
Applications
| Portable Power Switching | Level Translation |
|---|---|
Use Scenario: Controlling 3.3 V logic-driven loads from 5 V supply rails in handheld instrumentation. IC Role / Device Role / Timing Role: PNP switch enabling high-side sourcing with TTL/CMOS-compatible base drive. Use Value: VCE(sat) ≤ -0.25 V ensures <0.3 V drop across switch, preserving headroom for downstream LDOs or sensors. | Use Scenario: Converting 1.8 V microcontroller outputs to interface with 5 V legacy peripherals. IC Role / Device Role / Timing Role: Active pull-up translator using emitter-follower configuration. Use Value: hFE ≥ 100 at IC = -10 mA guarantees minimal base current draw (<100 μA), reducing MCU GPIO loading. |
| LED Driver | Audio Signal Amplifier |
Use Scenario: Driving indicator LEDs in automotive body control modules with 12 V supply. IC Role / Device Role / Timing Role: Low-side current sink with fixed base resistor for constant-current operation. Use Value: IC(max) = -200 mA supports multi-LED strings; Cob = 4.5 pF prevents RF coupling into adjacent CAN/LIN traces. | Use Scenario: First-stage preamplifier in battery-powered audio recorders with electret condenser microphones. IC Role / Device Role / Timing Role: Common-emitter amplifier biased at IC = -100 μA for low-noise gain. Use Value: NF = 4 dB at 10 Hz–15.7 kHz meets SNR >60 dB requirement; fT = 250 MHz avoids gain roll-off in audible band. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MMBT3906 | Same die, identical electrical specs; marking differs (no 'K' prefix), same SOT-23 package | No functional difference; accepted interchangeably in new designs per ON Semiconductor documentation | Select MMBT3906 when sourcing from distributors listing only standard ON Semi nomenclature |
| BC807-40 | hFE min = 250 @ IC = -100 mA vs. KST3906MTF's 100; Cob = 15 pF vs. 4.5 pF; VCEO = -45 V | Better gain consistency at high current but higher capacitance limits RF use; wider VCEO margin for industrial 24 V systems | Choose BC807-40 for high-current linear regulation where gain stability >250 is required and bandwidth <10 MHz suffices |
Compared with MMBT3906 and BC807-40, the KST3906MTF offers optimal balance of low Cob (4.5 pF), moderate hFE (100 at 10 mA), and proven SOT-23 reliability in portable power switching - making it preferred for space-constrained, battery-operated designs needing predictable turn-on/turn-off timing.
Availability
KST3906MTF is available at Aetrix Electronics and suitable for portable power switching, level translation, LED driver, and audio signal amplifier applications requiring stable component supply and SOT-23 footprint consistency.
Supply support for KST3906MTF 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, sensor, and connectivity solutions for automotive, industrial, and cloud infrastructure markets.
The KST3906MTF belongs to ON Semiconductor's general-purpose bipolar transistor product line, designed for cost-sensitive, high-volume applications requiring robust DC switching and moderate-frequency analog performance in compact SOT-23 packages.
FAQ
What is the pin configuration of the KST3906MTF?
The KST3906MTF uses standard SOT-23 pinout: Pin 1 is Base, Pin 2 is Emitter, Pin 3 is Collector. This matches JEDEC TO-236AB mechanical specification and is verified in the Fairchild KST3906 Rev. A3 datasheet Figure 1 layout diagram. The KST3906MTF marking "2A" on the top surface aligns with this pin assignment.
Does the KST3906MTF support switching at 1 MHz?
The KST3906MTF has tON = 70 ns and tOFF = 300 ns, yielding a theoretical maximum switching frequency near 1 MHz under ideal conditions. However, actual 1 MHz operation requires careful PCB layout to minimize stray capacitance and ensure adequate base drive strength - the KST3906MTF's fT = 250 MHz supports this, but thermal limits must be observed at sustained duty cycles.
Is the KST3906MTF RoHS compliant?
Yes, the KST3906MTF is RoHS compliant and lead-free per ON Semiconductor's product change notification PCN-17001, which confirms halogen-free molding compound and Pb-free termination finish. Compliance documentation is available via ON Semiconductor's Quality & Environmental page using the KST3906MTF part number.
Can the KST3906MTF replace a 2N3906 in existing designs?
The KST3906MTF is electrically and physically compatible with the 2N3906 in SOT-23 form factor, sharing identical VCEO, IC, hFE, and VCE(sat) specifications. However, the KST3906MTF's lower Cob (4.5 pF vs. typical 8 pF for 2N3906) may slightly improve high-frequency response - verify layout parasitics before drop-in replacement in RF-sensitive circuits.
What is the maximum operating temperature for continuous use of the KST3906MTF?
The KST3906MTF has a maximum junction temperature (TJ) rating of +150°C and a storage temperature range of -55°C to +150°C. For continuous operation at full 350 mW dissipation, ambient temperature must be limited to ≤+100°C assuming typical PCB thermal resistance; derating is required above that point - the KST3906MTF datasheet provides detailed thermal resistance curves in Figure 5.
KST3906MTF 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:
- PNP
- Current - Collector (Ic) (Max):
- 200 mA
- Voltage - Collector Emitter Breakdown (Max):
- 40 V
- Vce Saturation (Max) @ Ib, Ic:
- 400mV @ 5mA, 50mA
- Current - Collector Cutoff (Max):
- -
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 100 @ 10mA, 1V
- Power - Max:
- 350 mW
- Frequency - Transition:
- 250MHz
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
KST3906MTF FAQ
1.How can I place an order for KST3906MTF through Aetrix?
Please submit a Request for Quotation (RFQ) for KST3906MTF 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 KST3906MTF reliable?
The price and inventory of KST3906MTF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for KST3906MTF is usually 5 days.
3.What payment methods are accepted for KST3906MTF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for KST3906MTF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for KST3906MTF?
KST3906MTF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your KST3906MTF 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 KST3906MTF?
For technical support, including KST3906MTF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your KST3906MTF requirements.
6.How does Aetrix verify that KST3906MTF is sourced from the original manufacturer or authorized distributors?
All KST3906MTF 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 KST3906MTF meets industry standards.
7.What is the process for return or replacement of KST3906MTF?
All KST3906MTF units undergo pre-shipment inspection (PSI). If there is an issue with KST3906MTF, 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 KST3906MTF part is unused and in its original packaging.
Return procedure for KST3906MTF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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