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onsemi KSC1173YTSTUA
- Part No.:
- KSC1173YTSTUA
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-220-3
- Datasheet:
-
KSC1173YTSTUA.pdf
- Description:
- TRANS NPN 30V 3A TO-220-3
- Quantity:
- Payment:
- Shipping:
Inventory:9,306
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Product details
Overview
KSC1173YTSTUA from ON Semiconductor is an NPN epitaxial silicon power transistor in TO-220 package, rated for 3 A collector current and 10 W collector dissipation at TC = 25°C, with 30 V collector-emitter and collector-base breakdown voltages; used in low-frequency power amplifier and linear regulator circuits.
For engineers reviewing the KSC1173YTSTUA datasheet, pinout, applications, or equivalent options, key selection criteria include DC current gain (hFE = 70–240), VCE(sat) ≤ 0.8 V at IC = 2 A/IB = 0.2 A, fT = 100 MHz, Cob = 35 pF, and thermal derating above 25°C case temperature.
Technical Context
This device operates as a medium-power bipolar junction transistor optimized for linear and switching applications up to ~100 MHz. Its design emphasizes low saturation voltage and stable DC current gain across collector currents from 0.5 A to 2.5 A, with complementary pairing to KSA473 for push-pull configurations.
The KSC1173YTSTUA features epitaxial base construction for improved switching consistency and safe operating area (SOA) defined up to 10 W DC dissipation at 25°C, with linear derating to zero at 150°C junction temperature; output capacitance (Cob = 35 pF at VCB = 10 V) supports predictable high-frequency behavior in amplifier feedback paths.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Collector Current (IC) | 3 A - supports continuous load drive in power regulators and audio output stages |
| Collector Dissipation (PC) | 10 W at TC = 25°C - defines maximum steady-state power handling with heatsink |
| Breakdown Voltage (BVCEO) | 30 V - sets upper limit for supply rail compatibility in 24 V systems |
| DC Current Gain (hFE) | 70–240 - enables bias stability across operating points in Class-A/B amplifiers |
| VCE(sat) | 0.3–0.8 V at IC = 2 A/IB = 0.2 A - minimizes conduction loss in linear pass elements |
| fT | 100 MHz - ensures usable gain margin in low-frequency RF driver and broadband amplifier designs |
| Cob | 35 pF at VCB = 10 V - influences Miller effect and stability compensation in high-gain stages |
Pinout & Package
Package: TO-220 (3-lead, through-hole, insulated tab). Standard mechanical outline per Fairchild/ON Semiconductor drawing; tab electrically connected to collector.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Base) | Control electrode | Receives forward-biased current to modulate collector current; requires external base resistor for current-limited drive |
| 2 (Collector) | High-current output node | Connected to heatsink via insulated tab; carries full load current and dissipates majority of heat |
| 3 (Emitter) | Reference terminal | Typically grounded or tied to negative rail; provides return path for emitter current and bias reference |
Key Features
| Feature | Design Value |
|---|---|
| Complementary Pairing | Matched as NPN counterpart to KSA473 PNP transistor for balanced push-pull output stages |
| Low Saturation Voltage | VCE(sat) ≤ 0.8 V at 2 A enables <1.6 W conduction loss in linear regulator pass devices |
| High fT Bandwidth | 100 MHz fT supports stable operation in wideband audio drivers and broadband signal conditioning |
| Thermal Robustness | Junction temperature rating of 150°C allows operation in industrial ambient environments with proper heatsinking |
Applications
| Audio Power Amplifier | Linear Voltage Regulator |
|---|---|
Use Scenario: Output stage in discrete Class-AB audio amplifiers delivering up to 20 W into 8 Ω loads. IC Role / Device Role / Timing Role: NPN power switch amplifying input signal with minimal crossover distortion. Use Value: Low VCE(sat) and high hFE ensure efficient power delivery and stable quiescent current control. | Use Scenario: Pass transistor in adjustable linear regulators powering analog sensor subsystems. IC Role / Device Role / Timing Role: Series pass element regulating output voltage under variable load conditions. Use Value: 3 A current capability and 30 V BVCEO support 24 V input/5–15 V output configurations with margin. |
| DC Motor Driver | Power Supply Protection Circuit |
Use Scenario: Single-ended drive for small brushed DC motors in industrial actuators. IC Role / Device Role / Timing Role: Switching or linear current controller interfacing microcontroller GPIO. Use Value: TO-220 package enables direct heatsink mounting; SOA supports pulsed motor stall currents. | Use Scenario: Overcurrent foldback element in lab-grade bench power supplies. IC Role / Device Role / Timing Role: Current-sensing pass transistor triggering shutdown when load exceeds threshold. Use Value: Precise hFE classification (O/Y) ensures repeatable trip point calibration across production units. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar NPN power transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MJD122G | Higher BVCEO (80 V), lower hFE (20–100), same TO-220 package | Better suited for higher-voltage switching; less ideal for precision linear regulation due to wider hFE spread | Select when system supply exceeds 30 V or robustness against transients is prioritized over gain linearity |
| TIP31C | Same BVCEO (30 V), lower IC (3 A), higher VCE(sat) (1.2 V), TO-220 package | Lower efficiency in linear mode; broader hFE range (10–50) reduces bias predictability | Choose for cost-sensitive legacy designs where marginal VCE(sat) increase is acceptable |
Compared with MJD122G and TIP31C, the KSC1173YTSTUA offers superior hFE consistency and lower saturation voltage for linear applications, while maintaining identical voltage ratings and package compatibility-making it optimal for precision-regulated or audio-critical implementations where thermal and gain stability are essential.
Availability
KSC1173YTSTUA is available at Aetrix Electronics and suitable for audio power amplifiers, linear voltage regulators, DC motor drivers, and power supply protection circuits requiring stable component supply and long-term industrial availability.
Supply support for KSC1173YTSTUA 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 power management, analog, sensors, and connectivity solutions for automotive, industrial, and cloud infrastructure markets.
The KSC1173YTSTUA belongs to ON Semiconductor's legacy power bipolar transistor portfolio, originally developed by Fairchild Semiconductor for robust, discrete power control in linear and switching applications demanding reliability and thermal resilience.
FAQ
What is the maximum junction temperature for the KSC1173YTSTUA?
The KSC1173YTSTUA has a maximum junction temperature (TJ) rating of 150°C, as specified in its absolute maximum ratings table. This value defines the upper thermal limit for reliable operation; sustained operation near this limit requires careful heatsink design and derating per the published power derating curve. The KSC1173YTSTUA must be mounted with appropriate thermal interface material and mechanical clamping to maintain TJ within specification under full load.
Is the KSC1173YTSTUA pin-compatible with the KSA473?
No, the KSC1173YTSTUA is not pin-compatible with the KSA473. While they are complementary NPN/PNP pairs intended for matched use in push-pull circuits, the KSA473 uses a different pinout (Emitter-Base-Collector) versus the KSC1173YTSTUA's Base-Collector-Emitter arrangement. PCB layout must account for this inversion; direct substitution without board revision will result in incorrect biasing and potential device failure.
What does the 'Y' suffix in KSC1173YTSTUA indicate?
The 'Y' in KSC1173YTSTUA denotes the hFE classification bin: devices marked 'Y' have a DC current gain (hFE) range of 120–240 at VCE = 2 V and IC = 0.5 A. This tighter gain grouping improves predictability in bias-critical applications like linear regulators and Class-A amplifiers. The KSC1173YTSTUA is thus selected for designs requiring higher and more consistent current amplification than the 'O' bin (70–140).
Can the KSC1173YTSTUA be used in switching applications?
Yes, the KSC1173YTSTUA can be used in low-frequency switching applications such as PWM motor control or relay drivers, provided switching speed requirements remain below ~100 kHz. Its fT = 100 MHz and Cob = 35 pF support reasonable turn-on/turn-off times, but it lacks optimized switching characteristics (e.g., low storage time, integrated anti-saturation clamp) found in dedicated switching transistors. For the KSC1173YTSTUA, base drive must be sufficiently strong to avoid saturation delay and ensure clean transitions.
Does the KSC1173YTSTUA require a heatsink in all applications?
A heatsink is required for the KSC1173YTSTUA whenever power dissipation exceeds ~1.5 W at ambient temperatures above 40°C, based on its 10 W TC = 25°C rating and linear derating slope. Without forced airflow or heatsinking, even moderate loads (e.g., 1 A at 2 V VCE) generate >2 W-exceeding natural convection limits. The KSC1173YTSTUA's TO-220 tab is electrically connected to the collector, so electrical isolation hardware must be used if mounting to a common heatsink shared with other components.
KSC1173YTSTUA Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-220-3
- Packaging:
- Tube
- Product Status:
- Obsolete
- Transistor Type:
- NPN
- Current - Collector (Ic) (Max):
- 3 A
- Voltage - Collector Emitter Breakdown (Max):
- 30 V
- Vce Saturation (Max) @ Ib, Ic:
- 800mV @ 200mA, 2A
- Current - Collector Cutoff (Max):
- 1µA (ICBO)
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 120 @ 500mA, 2V
- Power - Max:
- 10 W
- Frequency - Transition:
- 100MHz
- Operating Temperature:
- 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TO-220-3
KSC1173YTSTUA FAQ
1.How can I place an order for KSC1173YTSTUA through Aetrix?
Please submit a Request for Quotation (RFQ) for KSC1173YTSTUA 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 KSC1173YTSTUA reliable?
The price and inventory of KSC1173YTSTUA are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for KSC1173YTSTUA is usually 5 days.
3.What payment methods are accepted for KSC1173YTSTUA?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for KSC1173YTSTUA transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for KSC1173YTSTUA?
KSC1173YTSTUA orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your KSC1173YTSTUA 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 KSC1173YTSTUA?
For technical support, including KSC1173YTSTUA datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your KSC1173YTSTUA requirements.
6.How does Aetrix verify that KSC1173YTSTUA is sourced from the original manufacturer or authorized distributors?
All KSC1173YTSTUA 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 KSC1173YTSTUA meets industry standards.
7.What is the process for return or replacement of KSC1173YTSTUA?
All KSC1173YTSTUA units undergo pre-shipment inspection (PSI). If there is an issue with KSC1173YTSTUA, 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 KSC1173YTSTUA part is unused and in its original packaging.
Return procedure for KSC1173YTSTUA:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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