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onsemi KSA473Y
- Part No.:
- KSA473Y
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-220-3
- Datasheet:
-
KSA473Y.pdf
- Description:
- TRANS PNP 30V 3A TO-220-3
- Quantity:
- Payment:
- Shipping:
Inventory:6,704
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Product details
Overview
KSA473Y from ON Semiconductor is a PNP 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 VCEO and −30 V VCBO, commonly used in low-frequency power amplifier and linear regulator circuits.
For engineers reviewing the KSA473Y datasheet, pinout, applications, or equivalent options, key selection criteria include DC current gain (hFE = 120–240 at IC = −2.5 A), VCE(sat) ≤ −0.8 V at IC = −2 A/IB = −0.2 A, fT = 100 MHz, and safe operating area compliance for industrial linear power stages.
Technical Context
The KSA473Y operates as a medium-power PNP bipolar junction transistor optimized for linear-mode applications including series pass regulation and Class-A/B audio output stages. Its complementary pairing with KSC1173 enables push-pull configurations without cross-conduction risk.
Designed for operation up to 150°C junction temperature, it features low saturation voltage (−0.3 V min at IC = −2 A), tight hFE classification (Y grade: 120–240), and 40 pF Cob at VCB = −10 V, supporting stable biasing in feedback-controlled power circuits.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Collector Current (IC) | −3 A - supports continuous load current in discrete linear regulators and amplifier output stages |
| VCEO / VCBO | −30 V - defines maximum allowable voltage across collector-emitter or collector-base under open-base conditions |
| PC (TC = 25°C) | 10 W - sets thermal design baseline for heatsink sizing in non-switching applications |
| hFE (Y grade) | 120–240 at IC = −2.5 A - ensures predictable base drive requirements in high-current linear circuits |
| VCE(sat) | ≤ −0.8 V at IC = −2 A, IB = −0.2 A - minimizes conduction loss and self-heating in saturated switching or quasi-saturated regulation |
| fT | 100 MHz - enables stable frequency response up to audio band with margin for phase compensation |
| Cob | 40 pF at VCB = −10 V - influences Miller effect and stability in high-gain amplifier topologies |
Pinout & Package
Package: TO-220 (3-pin, straight lead, insulated tab). Standard JEDEC TO-220AB variant per drawing TO220B03REV9, with pin 1 = Base, pin 2 = Collector, pin 3 = Emitter.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Base) | Current-controlled input terminal | Receives negative base current to enable conduction; requires external current-limiting resistor in most driver circuits |
| 2 (Collector) | Main current sink terminal | Connected to higher potential (e.g., unregulated rail); carries full load current to emitter |
| 3 (Emitter) | Main current source terminal | Typically tied to load or ground reference; voltage drop here affects output regulation accuracy |
Key Features
| Feature | Design Value |
|---|---|
| Complementary pair | Matched to KSC1173 NPN for balanced push-pull amplifier designs |
| hFE classification Y | Guaranteed 120–240 gain range ensures consistent base drive design across production lots |
| Low VCE(sat) | −0.3 V minimum reduces power loss and improves efficiency in linear regulator pass elements |
| High fT | 100 MHz bandwidth supports stable closed-loop compensation in audio and control amplifiers |
| TO-220 mechanical standard | Enables use of widely available heatsinks and mounting hardware in industrial power modules |
Applications
| Linear Voltage Regulator | Audio Power Amplifier |
|---|---|
Use Scenario: Discrete series pass element in adjustable 3-terminal regulator designs delivering up to 2.5 A output current. IC Role / Device Role / Timing Role: PNP pass transistor controlling output voltage via feedback loop error amplifier. Use Value: Low VCE(sat) and high hFE reduce dropout voltage and improve load regulation accuracy over temperature. | Use Scenario: Complementary output stage in Class-AB audio amplifiers driving 4–8 Ω speakers. IC Role / Device Role / Timing Role: Negative-rail output device providing symmetrical current sourcing/sinking capability. Use Value: Matched hFE and SOA with KSC1173 enables low-distortion, thermally stable push-pull operation. |
| DC Motor Driver | Power Supply Protection |
Use Scenario: High-side switch in brushed DC motor control circuits requiring reverse polarity protection. IC Role / Device Role / Timing Role: PNP-based high-side switch enabling bidirectional current flow with external logic-level drive. Use Value: −30 V VCEO withstands inductive kickback during motor commutation without snubber circuitry. | Use Scenario: Overcurrent foldback element in lab-grade bench power supplies with adjustable current limit. IC Role / Device Role / Timing Role: Current-sensing pass transistor in analog foldback loop responding to sense resistor voltage. Use Value: Tight hFE tolerance and 150°C TJ rating ensure reliable trip-point consistency across ambient conditions. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP power transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MJD47T4G | TO-252 (DPAK) package, −4 A IC, −40 V VCEO, hFE = 75–220 | Suitable for surface-mount PCBs; lower thermal resistance but reduced voltage margin | Select when board space is constrained and −40 V rating suffices for system rail voltage |
| BD139 | TO-126 package, −1.5 A IC, −80 V VCEO, hFE = 40–250 | Higher voltage rating but lower current capacity; not pin-compatible | Choose for legacy through-hole designs needing higher breakdown voltage and lower cost |
Compared with MJD47T4G and BD139, the KSA473Y offers optimal balance of current handling (−3 A), voltage rating (−30 V), and TO-220 thermal performance for through-hole linear power stages where mechanical robustness and heatsink compatibility are prioritized.
Availability
KSA473Y is available at Aetrix Electronics and suitable for linear voltage regulators, audio power amplifiers, DC motor drivers, and power supply protection circuits requiring stable component supply and long-term industrial availability.
Supply support for KSA473Y 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, sensor, and discrete solutions for automotive, industrial, and consumer markets.
The KSA473Y belongs to ON Semiconductor's legacy Fairchild discrete transistor portfolio, designed specifically for robust, cost-effective linear power control in industrial and audio applications.
FAQ
What is the pin configuration of the KSA473Y?
The KSA473Y uses a standard TO-220 package with pin 1 = Base, pin 2 = Collector, and pin 3 = Emitter when viewed with the tab facing away and leads downward. This configuration is confirmed in the official Fairchild KSA473 Rev. A2 datasheet and maintained in ON Semiconductor's product documentation for the KSA473Y.
Does the KSA473Y have a guaranteed hFE range?
Yes, the KSA473Y is classified as "Y" grade with a guaranteed DC current gain (hFE) range of 120–240 at VCE = −2 V and IC = −2.5 A, as specified in the Electrical Characteristics table of the official datasheet. This tight hFE binning ensures predictable base drive requirements in production designs.
Can the KSA473Y be used as a direct replacement for the KSA473?
Yes, the KSA473Y is the Y-grade variant of the KSA473 family and shares identical absolute maximum ratings, pinout, package, and electrical characteristics except for the hFE classification band. The "Y" suffix denotes the higher-gain bin (120–240), while standard KSA473 may include O-grade (70–140); both are functionally interchangeable where gain tolerance permits.
What is the maximum junction temperature for the KSA473Y?
The KSA473Y has a maximum junction temperature (TJ) rating of 150°C, as defined in the Absolute Maximum Ratings table. This allows operation in demanding industrial environments when paired with appropriate heatsinking and derated power dissipation per the published thermal derating curve.
Is the KSA473Y RoHS compliant?
Yes, the KSA473Y is RoHS compliant and meets the requirements of Directive 2011/65/EU, as confirmed by ON Semiconductor's material declarations and packaging data. Lead-free finish and halogen-free molding compound are standard for this part number in current production.
KSA473Y Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-220-3
- Packaging:
- Bulk
- Product Status:
- Obsolete
- Transistor Type:
- PNP
- 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
KSA473Y FAQ
1.How can I place an order for KSA473Y through Aetrix?
Please submit a Request for Quotation (RFQ) for KSA473Y 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 KSA473Y reliable?
The price and inventory of KSA473Y are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for KSA473Y is usually 5 days.
3.What payment methods are accepted for KSA473Y?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for KSA473Y transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for KSA473Y?
KSA473Y orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your KSA473Y 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 KSA473Y?
For technical support, including KSA473Y datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your KSA473Y requirements.
6.How does Aetrix verify that KSA473Y is sourced from the original manufacturer or authorized distributors?
All KSA473Y 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 KSA473Y meets industry standards.
7.What is the process for return or replacement of KSA473Y?
All KSA473Y units undergo pre-shipment inspection (PSI). If there is an issue with KSA473Y, 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 KSA473Y part is unused and in its original packaging.
Return procedure for KSA473Y:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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