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Toshiba Semiconductor and Storage TK9A55DA(STA4,Q,M)

Name: TK9A55DA(STA4,Q,M)
Brand: Toshiba Semiconductor and Storage
SKU: TK9A55DA(STA4,Q,M)
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: TK9A55DA(STA4,Q,M)

Manufacturer:: Toshiba Semiconductor and Storage

Category:: FETs, MOSFETs

Package:: TO-220-3 Full Pack

Datasheet:: TK9A55DA(STA4,Q,M).pdf

Description:: MOSFET N-CH 550V 8.5A TO220SIS

Quantity:: RFQ Add To RFQ list

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Product details

Overview

TK9A55DA(STA4,Q,M) from Toshiba is a silicon N-channel power MOSFET designed for high-voltage switching regulator applications. It features a 550 V drain-source breakdown voltage (V_(BR)DSS), low R_DS(ON) of 0.68 Ω (typ.) at V_GS = 10 V and I_D = 4.3 A, 4.7 S forward transfer admittance (|Y_fs|), and 252 mJ single-pulse avalanche energy - enabling robust operation in offline SMPS and industrial DC-DC converters.

For engineers reviewing the TK9A55DA(STA4,Q,M) datasheet, TK9A55DA(STA4,Q,M) pinout, TK9A55DA(STA4,Q,M) application, or TK9A55DA(STA4,Q,M) equivalent, key selection criteria include its 550 V rating, 8.5 A continuous drain current, SC-67 package thermal performance (R_th(ch-c) = 3.125 °C/W), and verified avalanche ruggedness for flyback and resonant converter topologies.

Technical Context

This π-MOSⅦ-generation device uses planar vertical DMOS structure optimized for high-voltage switching with enhanced avalanche capability. Its enhancement-mode gate threshold (V_th = 2–4 V) ensures reliable turn-on control under standard 10 V gate drive, while low Crss (5 pF) and Q_gd (7 nC) support fast, low-loss switching in hard-switched topologies.

The integrated body diode exhibits V_DSF = −1.7 V at I_DR = 8.5 A and t_rr = 1200 ns, making it suitable for freewheeling paths where controlled reverse recovery is required. Thermal design is anchored to the SC-67 package's 3.125 °C/W channel-to-case resistance, enabling 40 W dissipation at T_c = 25°C.

Key Specifications

Parameter	Value and Actual Design Meaning
V_DSS	550 V - supports 380 V AC input rectified systems with margin for surge and ringing
R_DS(ON)	0.68 Ω (typ.) - enables <1.5 W conduction loss at 4.3 A, critical for efficiency in 50–200 W SMPS
I_D (cont)	8.5 A - defines maximum steady-state output power handling in TO-220F-equivalent SC-67 package
E_AS	252 mJ - provides proven single-pulse avalanche robustness for clamp-free flyback designs
\|Y_fs\|	4.7 S (typ.) - indicates strong transconductance for stable closed-loop regulation under load transients
C_iss/C_oss	1050 / 100 pF - low output capacitance reduces turn-off losses; C_iss enables predictable gate drive sizing
Q_g	20 nC - determines gate driver current requirement (~1–2 A peak for 100 ns rise time)

Pinout & Package

TK9A55DA(STA4,Q,M) is housed in the SC-67 package (Toshiba designation: 2-10U1B), a through-hole variant of TO-220F with insulated tab and JEITA-standard footprint. It weighs 1.7 g and features a 3.125 °C/W channel-to-case thermal resistance.

Pin/Terminal	Circuit Role	Design Meaning
1 (Gate)	Control electrode	Receives 2–4 V threshold signal; requires 10 V for full enhancement; ESD-sensitive (±30 V max)
2 (Drain)	High-side power terminal	Connected to primary winding or HV rail; rated for 550 V and 8.5 A continuous
3 (Source)	Reference and return path	Serves as power ground reference; carries full load current and body diode reverse recovery charge (Q_rr = 11 μC)

Key Features

Feature	Design Value
π-MOSⅦ process technology	Delivers optimized R_DS(ON) × Q_g figure-of-merit for high-voltage switching efficiency
Single-pulse avalanche rating	252 mJ validated per JEDEC JESD24-11 test conditions (V_DD = 90 V, L = 6.04 mH)
Low Crss (5 pF)	Minimizes Miller-induced shoot-through risk and improves dv/dt immunity in high-noise environments
Integrated body diode	Rated for 8.5 A reverse current with −1.7 V forward drop and 1200 ns recovery - usable in synchronous rectification auxiliary paths
SC-67 mechanical compatibility	Mounts on standard TO-220 heatsinks with insulated mounting; 15.0 mm lead spacing matches legacy layouts

Applications

AC-DC Flyback Converter	Industrial DC-DC Isolated Supply
Use Scenario: Primary-side switch in universal-input (85–265 V AC) flyback converters delivering 24–48 V/2–5 A to PLC I/O modules. IC Role / Device Role / Timing Role: High-voltage power switch operating at 65–130 kHz with self-clamped avalanche during demagnetization. Use Value: 252 mJ E_AS eliminates need for external RCD clamp, reducing BOM count and improving reliability over 10-year field life.	Use Scenario: Main switching element in 48 V input isolated DC-DC converters powering motor drives and sensor interfaces in factory automation. IC Role / Device Role / Timing Role: Primary-side MOSFET in forward or half-bridge topology, handling 550 V transient surges on industrial bus lines. Use Value: 550 V V_DSS and 8.5 A I_D enable direct replacement of older 500 V parts without derating or layout change.
LED Driver Power Stage	UPS Inverter Half-Bridge
Use Scenario: Switching transistor in constant-current LED drivers for street lighting (300–400 V DC bus). IC Role / Device Role / Timing Role: High-side switch controlling LED string current via PWM dimming at 1–10 kHz. Use Value: Low R_DS(ON) (0.68 Ω) limits conduction loss to <1.5 W at 4.3 A, maintaining >92% efficiency at full load.	Use Scenario: Upper-leg switch in 200–300 V DC bus half-bridge inverters for small UPS systems (500–1500 VA). IC Role / Device Role / Timing Role: Fast-turning high-voltage switch managing dead-time-controlled AC output generation. Use Value: 20 nC Q_g and 25 ns t_r allow clean 50 kHz switching with minimal overlap loss and gate driver stress.

AC-DC Flyback Converter

Industrial DC-DC Isolated Supply

Use Scenario: Primary-side switch in universal-input (85–265 V AC) flyback converters delivering 24–48 V/2–5 A to PLC I/O modules.

IC Role / Device Role / Timing Role: High-voltage power switch operating at 65–130 kHz with self-clamped avalanche during demagnetization.

Use Value: 252 mJ E_AS eliminates need for external RCD clamp, reducing BOM count and improving reliability over 10-year field life.

Use Scenario: Main switching element in 48 V input isolated DC-DC converters powering motor drives and sensor interfaces in factory automation.

IC Role / Device Role / Timing Role: Primary-side MOSFET in forward or half-bridge topology, handling 550 V transient surges on industrial bus lines.

Use Value: 550 V V_DSS and 8.5 A I_D enable direct replacement of older 500 V parts without derating or layout change.

LED Driver Power Stage

UPS Inverter Half-Bridge

Use Scenario: Switching transistor in constant-current LED drivers for street lighting (300–400 V DC bus).

IC Role / Device Role / Timing Role: High-side switch controlling LED string current via PWM dimming at 1–10 kHz.

Use Value: Low R_DS(ON) (0.68 Ω) limits conduction loss to <1.5 W at 4.3 A, maintaining >92% efficiency at full load.

Use Scenario: Upper-leg switch in 200–300 V DC bus half-bridge inverters for small UPS systems (500–1500 VA).

IC Role / Device Role / Timing Role: Fast-turning high-voltage switch managing dead-time-controlled AC output generation.

Use Value: 20 nC Q_g and 25 ns t_r allow clean 50 kHz switching with minimal overlap loss and gate driver stress.

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage N-channel MOSFET applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
STP9NK50ZFP	500 V V_DSS, 0.75 Ω R_DS(ON), 22 nC Q_g, TO-220FP package	Limited to ≤400 V AC input systems; lower avalanche rating (120 mJ)	Acceptable for cost-sensitive 200–300 W designs where 550 V margin is not required
IXTP50N10P	100 V V_DSS, 0.022 Ω R_DS(ON), 75 nC Q_g, TO-220 package	Not suitable for high-voltage primary-side use; intended for low-V_DS secondary-side or DC-DC stages	Only viable as alternative if system redesign lowers bus voltage to ≤60 V - not a drop-in replacement

Compared with STP9NK50ZFP and IXTP50N10P, TK9A55DA(STA4,Q,M) uniquely balances 550 V rating, 252 mJ avalanche energy, and 0.68 Ω R_DS(ON) in an SC-67 package - making it the only option among the three qualified for unclamped flyback operation above 380 V DC bus.

Availability

TK9A55DA(STA4,Q,M) is available at Aetrix Electronics and suitable for AC-DC flyback converters, industrial DC-DC isolated supplies, and LED driver power stages requiring stable component supply and long-term lifecycle assurance.

Supply support for TK9A55DA(STA4,Q,M) 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

Toshiba Electronic Devices & Storage Corporation is a Japanese semiconductor manufacturer specializing in power devices, logic ICs, and memory solutions, with global manufacturing and quality certification to ISO 9001 and IATF 16949.

TK9A55DA(STA4,Q,M) belongs to Toshiba's π-MOSⅦ high-voltage power MOSFET product line, engineered specifically for rugged, high-efficiency switching regulators in industrial and commercial power supplies.

FAQ

What is the maximum continuous drain current for TK9A55DA(STA4,Q,M) at 25°C case temperature?

The TK9A55DA(STA4,Q,M) supports a maximum continuous drain current (I_D) of 8.5 A when the case temperature (T_c) is maintained at 25°C. This rating assumes proper heatsinking and adherence to the specified thermal resistance R_th(ch-c) = 3.125 °C/W. At higher case temperatures, the current must be derated linearly per the Safe Operating Area curve in the datasheet.

Does TK9A55DA(STA4,Q,M) have avalanche capability, and how is it specified?

Yes, TK9A55DA(STA4,Q,M) is fully rated for single-pulse avalanche operation with E_AS = 252 mJ under defined test conditions (V_DD = 90 V, L = 6.04 mH, I_AR = 8.5 A, T_ch = 25°C). This validated capability allows safe operation in unclamped inductive switching events common in flyback and forward converters without external snubbers.

What is the gate threshold voltage range for TK9A55DA(STA4,Q,M), and how does it affect drive requirements?

The gate threshold voltage (V_th) for TK9A55DA(STA4,Q,M) is specified as 2.0–4.0 V at V_DS = 10 V and I_D = 1 mA. This range ensures reliable turn-on with standard 5 V or 10 V gate drivers while avoiding unintended conduction due to noise. For full enhancement and minimal R_DS(ON), a V_GS ≥ 10 V is recommended per the datasheet test condition.

Is TK9A55DA(STA4,Q,M) RoHS compliant, and what marking indicates compliance?

Yes, TK9A55DA(STA4,Q,M) is RoHS compliant. Compliance is indicated by the marking "[[G]]/RoHS COMPATIBLE" or "[[G]]/RoHS [[Pb]]" on the device body, per Toshiba's labeling convention. The part meets Directive 2011/65/EU and contains lead only as an exempted impurity in solder or die attach materials, consistent with Annex III.

What package type does TK9A55DA(STA4,Q,M) use, and how does it compare to TO-220F?

TK9A55DA(STA4,Q,M) uses the SC-67 package (Toshiba designation: 2-10U1B), which is functionally equivalent to TO-220F - featuring an insulated metal tab, same pinout (G-D-S), and identical 15.0 mm lead spacing. It offers identical thermal performance (R_th(ch-c) = 3.125 °C/W) and mechanical mounting compatibility with standard TO-220 heatsinks.

TK9A55DA(STA4,Q,M) Specifications

Product attributes: Attribute value

Manufacturer:: Toshiba Semiconductor and Storage

Series:: π-MOSVII

Package/Case:: TO-220-3 Full Pack

Packaging:: Tube

Product Status:: Active

FET Type:: N-Channel

Technology:: MOSFET (Metal Oxide)

Drain to Source Voltage (Vdss):: 550 V

Current - Continuous Drain (Id) @ 25°C:: 8.5A (Ta)

Drive Voltage (Max Rds On, Min Rds On):: 10V

Rds On (Max) @ Id, Vgs:: 860mOhm @ 4.3A, 10V

Vgs(th) (Max) @ Id:: 4V @ 1mA

Gate Charge (Qg) (Max) @ Vgs:: 20 nC @ 10 V

Vgs (Max):: ±30V

Input Capacitance (Ciss) (Max) @ Vds:: 1050 pF @ 25 V

FET Feature:: -

Power Dissipation (Max):: 40W (Tc)

Operating Temperature:: 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-220SIS

TK9A55DA(STA4,Q,M) FAQ

1.How can I place an order for TK9A55DA(STA4,Q,M) through Aetrix?

Please submit a Request for Quotation (RFQ) for TK9A55DA(STA4,Q,M) 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 TK9A55DA(STA4,Q,M) reliable?

The price and inventory of TK9A55DA(STA4,Q,M) are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TK9A55DA(STA4,Q,M) is usually 5 days.

3.What payment methods are accepted for TK9A55DA(STA4,Q,M)?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TK9A55DA(STA4,Q,M) transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for TK9A55DA(STA4,Q,M)?

TK9A55DA(STA4,Q,M) orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your TK9A55DA(STA4,Q,M) 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 TK9A55DA(STA4,Q,M)?

For technical support, including TK9A55DA(STA4,Q,M) datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TK9A55DA(STA4,Q,M) requirements.

6.How does Aetrix verify that TK9A55DA(STA4,Q,M) is sourced from the original manufacturer or authorized distributors?

All TK9A55DA(STA4,Q,M) 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 TK9A55DA(STA4,Q,M) meets industry standards.

7.What is the process for return or replacement of TK9A55DA(STA4,Q,M)?

All TK9A55DA(STA4,Q,M) units undergo pre-shipment inspection (PSI). If there is an issue with TK9A55DA(STA4,Q,M), 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 TK9A55DA(STA4,Q,M) part is unused and in its original packaging.

Return procedure for TK9A55DA(STA4,Q,M):

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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