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onsemi KST56MTF
- Part No.:
- KST56MTF
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
KST56MTF.pdf
- Description:
- TRANS PNP 80V 0.5A SOT-23-3
- Quantity:
- Payment:
- Shipping:
Inventory:9,190
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Product details
Overview
KST56MTF from ON Semiconductor is a PNP epitaxial silicon transistor designed for general-purpose switching and amplification in low-power circuits, featuring VCEO = -80 V, IC = -500 mA, PC = 350 mW, hFE ≥ 50 at IC = -100 mA, and fT = 50 MHz - commonly used in discrete logic interface, relay driver, and level-shifting stages.
For engineers reviewing the KST56MTF datasheet, pinout, applications, or equivalent options, key selection criteria include guaranteed VCEO rating, SOT-23 thermal resistance (Rθj-a = 357°C/W), saturation voltage (VCE(sat) = -0.25 V @ IC = -100 mA), and complementary pairing with KST06.
Technical Context
This device operates as a medium-voltage PNP bipolar junction transistor with fixed emitter-base and collector-base breakdown limits (VEBO = -4 V, VCBO = -80 V), optimized for DC-coupled switching where low VCE(sat) and stable hFE across 10–100 mA bias are required.
Its SOT-23 package enables surface-mount integration in space-constrained designs, and its fT = 50 MHz supports moderate-speed digital edge control and audio-frequency amplification without requiring external compensation.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | -80 V - maximum safe collector-emitter reverse voltage before breakdown in common-emitter configuration |
| IC | -500 mA - continuous collector current limit defining maximum load drive capability |
| PC | 350 mW - maximum power dissipation at Ta = 25°C, constraining usable current/voltage combinations in ambient air |
| hFE | ≥50 @ IC = -100 mA - minimum DC current gain ensuring reliable base-driven switching with ≤10 mA base current |
| VCE(sat) | -0.25 V @ IC = -100 mA, IB = -10 mA - low saturation voltage enabling efficient on-state power loss below 25 mW |
| fT | 50 MHz - unity-gain bandwidth limiting usable frequency range for small-signal amplification or fast switching |
Pinout & Package
SOT-23 plastic surface-mount package with gull-wing leads; standardized 3-pin layout supporting automated placement and reflow soldering.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base | Control terminal accepting forward-biased current to enable conduction between collector and emitter |
| 2 | Emitter | Current source terminal in PNP configuration; connected to higher potential rail in typical switch layouts |
| 3 | Collector | Current sink terminal; delivers load current to ground or lower-potential node when biased on |
Key Features
| Feature | Design Value |
|---|---|
| High VCEO rating | -80 V enables use in 48 V industrial bus interfaces and automotive subsystems with transient margin |
| Low VCE(sat) | -0.25 V reduces conduction loss in high-duty-cycle switching applications like LED drivers |
| Complementary pair | Designed as direct counterpart to KST06 NPN, simplifying push-pull stage implementation |
| SOT-23 footprint | Standardized 3-pin package allows drop-in replacement in legacy designs using similar small-signal transistors |
Applications
| Relay Driver Stage | Logic Level Shifter |
|---|---|
Use Scenario: Driving 12 V/24 V electromagnetic relays from 3.3 V or 5 V microcontroller GPIO pins. IC Role / Device Role / Timing Role: PNP switch providing inverted current sink path to relay coil, with base resistor limiting IB to ensure full saturation. Use Value: VCEO = -80 V accommodates relay coil flyback spikes up to 60 V, eliminating need for external clamping diodes in many cases. | Use Scenario: Translating TTL/CMOS logic outputs to higher-voltage domains (e.g., 12 V) for sensor interface or actuator control. IC Role / Device Role / Timing Role: Active-low level shifter using emitter-follower or common-emitter inversion topology. Use Value: hFE ≥ 50 ensures sufficient drive strength at 100 mA loads while maintaining <1 µs propagation delay due to fT = 50 MHz. |
| Discrete Amplifier Stage | Power Supply Sequencing Control |
Use Scenario: Low-noise preamplifier for analog sensor signals in battery-powered instrumentation. IC Role / Device Role / Timing Role: Common-emitter amplifier with emitter degeneration resistor for DC bias stability and AC gain control. Use Value: fT = 50 MHz supports bandwidth up to ~5 MHz with gain ≤10, suitable for piezoelectric or thermocouple signal conditioning. | Use Scenario: Enabling/disabling auxiliary rails (e.g., 3.3 V, 5 V) based on main supply status in multi-rail power systems. IC Role / Device Role / Timing Role: High-side enable switch controlling PMOS gate drive or LDO EN pin via open-collector logic. Use Value: IC = -500 mA rating allows direct control of enable inputs drawing up to 400 µA without external buffering. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MMBT56 | Same die, identical electrical specs; marking code differs (2G vs. MMBT56), same SOT-23 package | No functional difference; used interchangeably in production where marking compliance is not mandated | Select MMBT56 when standard ON Semiconductor part numbering is required for procurement or traceability |
| PN2907A | Higher Rθj-a (400°C/W), lower fT (≈30 MHz), same VCEO (-60 V) but lower than KST56MTF's -80 V rating | Limited to ≤30 MHz operation and less robust against voltage transients in 48 V systems | Choose PN2907A only if legacy design uses TO-92 and board redesign is not feasible |
Compared with MMBT56 and PN2907A, the KST56MTF offers superior voltage margin (−80 V), tighter thermal resistance (357°C/W), and higher bandwidth (50 MHz), making it optimal for new SMT designs requiring reliability in industrial voltage domains.
Availability
KST56MTF is available at Aetrix Electronics and suitable for relay driver circuits, logic level shifters, discrete amplifier stages, and power supply sequencing control requiring stable component supply and consistent SOT-23 form factor.
Supply support for KST56MTF 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 connectivity solutions for automotive, industrial, cloud, and consumer markets.
The KST56MTF belongs to ON Semiconductor's legacy small-signal transistor portfolio, originally developed by Fairchild and optimized for cost-sensitive, high-volume discrete switching and amplification applications.
FAQ
What is the maximum collector-emitter voltage rating for KST56MTF?
The KST56MTF has a guaranteed VCEO rating of -80 V at Ta = 25°C. This value represents the maximum reverse voltage that can be applied between collector and emitter with the base open before breakdown occurs. It is validated per JEDEC test conditions (VCE = -80 V, IB = 0) and defines the safe operating area for high-side switching applications. Engineers must verify derating curves in the official ON Semiconductor datasheet for elevated temperature operation.
Is KST56MTF pin-compatible with KST55MTF?
Yes, KST56MTF is pin-compatible with KST55MTF - both use identical SOT-23 packaging and share the same pinout (1: Base, 2: Emitter, 3: Collector). However, KST56MTF offers higher VCEO (-80 V vs. -60 V) and identical hFE/fT performance. The devices are not interchangeable without verifying voltage margin requirements in the target circuit, especially in 48 V or transient-prone environments where KST55MTF may enter breakdown.
What is the typical DC current gain (hFE) of KST56MTF at 100 mA collector current?
The KST56MTF exhibits hFE ≥ 50 when tested at VCE = -1 V and IC = -100 mA. This minimum guaranteed value ensures predictable base drive requirements - for example, ≤10 mA IB suffices to saturate the transistor under those conditions. Actual hFE may vary between 50–250 depending on lot and operating point; design margins should account for this spread using worst-case values from the datasheet's hFE distribution graph.
Does KST56MTF require a heatsink in standard SOT-23 mounting?
No, KST56MTF does not require an external heatsink under typical operating conditions. With Rθj-a = 357°C/W and PC = 350 mW max, junction temperature rise is approximately 125°C above ambient at full power - acceptable only for short pulses or low-duty-cycle operation. For continuous 350 mW dissipation, PCB copper area (≥1 cm² 2-oz copper) is recommended to improve thermal conduction. Most applications operate well below PC(max), keeping Tj within safe limits without added thermal mass.
How does KST56MTF compare to its NPN complement KST06?
KST56MTF is the designated PNP complement to the NPN KST06 transistor, sharing identical SOT-23 package, pinout, and thermal characteristics. Both exhibit matched VCEO/VCBO ratings (KST06: 80 V), comparable hFE ranges, and symmetric saturation behavior - enabling balanced push-pull output stages, H-bridge drivers, and differential amplifiers. Their complementary pairing simplifies BOM consolidation and layout symmetry in dual-transistor topologies.
KST56MTF 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):
- 500 mA
- Voltage - Collector Emitter Breakdown (Max):
- 80 V
- Vce Saturation (Max) @ Ib, Ic:
- 250mV @ 10mA, 100mA
- Current - Collector Cutoff (Max):
- 100nA
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 50 @ 100mA, 1V
- Power - Max:
- 350 mW
- Frequency - Transition:
- 50MHz
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
KST56MTF FAQ
1.How can I place an order for KST56MTF through Aetrix?
Please submit a Request for Quotation (RFQ) for KST56MTF 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 KST56MTF reliable?
The price and inventory of KST56MTF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for KST56MTF is usually 5 days.
3.What payment methods are accepted for KST56MTF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for KST56MTF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for KST56MTF?
KST56MTF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your KST56MTF 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 KST56MTF?
For technical support, including KST56MTF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your KST56MTF requirements.
6.How does Aetrix verify that KST56MTF is sourced from the original manufacturer or authorized distributors?
All KST56MTF 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 KST56MTF meets industry standards.
7.What is the process for return or replacement of KST56MTF?
All KST56MTF units undergo pre-shipment inspection (PSI). If there is an issue with KST56MTF, 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 KST56MTF part is unused and in its original packaging.
Return procedure for KST56MTF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
KST56MTF Tags
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MMBT3906LT1G
onsemi
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MMBT3904-7-F
Diodes Incorporated
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MMBT3904LT1G
onsemi
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MMBT3906-7-F
Diodes Incorporated
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MMBT3904-TP
Micro Commercial Co
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MMBT2222A-7-F
Diodes Incorporated
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BC846BLT1G
onsemi
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BC847B,215
Nexperia USA Inc.
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SMMBT3904LT1G
onsemi
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MMBT2222A-TP
Micro Commercial Co
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MMBTA06LT1G
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MMBT2222ALT1G
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