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Home > Products > Discrete Semiconductor Products > Diodes > Rectifiers > Single Diodes

STMicroelectronics STPS340B-TR

Name: STPS340B-TR
Brand: STMicroelectronics
SKU: STPS340B-TR
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: STPS340B-TR

Manufacturer:: STMicroelectronics

Category:: Single Diodes

Package:: TO-252-3, DPAK (2 Leads + Tab), SC-63

Datasheet:: STPS340B-TR.pdf

Description:: DIODE SCHOTTKY 40V 3A DPAK

Quantity:: RFQ Add To RFQ list

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Inventory:7,982

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Product details

Overview

STPS340B-TR from STMicroelectronics is a 40 V, 3 A average forward current Schottky rectifier in DPAK package, optimized for high-frequency DC-DC converters and switch-mode power supplies. It delivers low forward voltage drop (0.52 V typ. at 3 A, 125 °C), avalanche-rated operation, and low thermal resistance (R_th(j-c) = 5.5 °C/W) for efficient thermal management in telecom and TV power supplies.

For engineers reviewing the STPS340B-TR datasheet, STPS340B-TR pinout, STPS340B-TR application, or STPS340B-TR equivalent, key selection criteria include junction-to-case thermal resistance, repetitive peak reverse voltage rating, surge current capability (75 A), and ECOPACK2 compliance for RoHS-constrained industrial designs.

Technical Context

This Schottky rectifier uses a planar silicon structure with metal-semiconductor junction to achieve negligible reverse recovery charge and extremely fast switching-critical for minimizing losses in >100 kHz SMPS topologies. Its low V_F and low R_th(j-c) enable high efficiency in compact, thermally constrained layouts.

The device operates up to 150 °C junction temperature and supports avalanche energy handling (90 W, 10 µs pulse), making it suitable for transient-prone input stages in offline AC-DC front-ends and battery charger secondary-side rectification where reliability under overvoltage stress is required.

Key Specifications

Parameter	Value and Actual Design Meaning
V_RRM	40 V - Maximum repetitive reverse blocking voltage; defines safe operating range in 36 V nominal DC bus applications.
I_F(AV)	3 A - Average forward current at T_L = 135 °C (DPAK); sets continuous conduction capability in 24–48 V output rails.
V_F(typ.)	0.52 V @ 3 A, 125 °C - Low conduction loss enables >95% efficiency in high-current, low-voltage outputs.
R_th(j-c)	5.5 °C/W - Junction-to-case thermal resistance; allows direct heatsink mounting for high-power density designs.
I_FSM	75 A - Non-repetitive surge current (10 ms sinusoidal); withstands inrush and fault currents in power supply startup.
P_ARM	90 W - Repetitive peak avalanche power (10 µs pulse, T_j = 125 °C); provides robustness against line transients.

Pinout & Package

STPS340B-TR is housed in a surface-mount DPAK (TO-252) package with three terminals: anode, cathode, and exposed thermal pad (connected to cathode). The thermal pad enhances heat transfer to PCB copper and must be soldered to a dedicated thermal land per Figure 26 in DS0792.

Pin/Terminal	Circuit Role	Design Meaning
Anode	Input current terminal	Connected to transformer secondary or switching node; carries full load current into the diode.
Cathode	Output current terminal	Connected to output capacitor and load; polarity-sensitive connection determines rectification direction.
Thermal Pad	Electrical and thermal interface	Internally tied to cathode; must be soldered to ≥40 mm² copper area for R_th(j-a) ≤ 30 °C/W performance.

Key Features

Feature	Design Value
Avalanche-rated operation	90 W repetitive peak avalanche power enables reliable clamping during voltage spikes without derating.
Low thermal resistance	R_th(j-c) = 5.5 °C/W allows direct PCB heatsinking-no external heatsink needed for ≤3 A continuous loads.
ECOPACK2 compliance	Lead-free, halogen-free, RoHS-compliant packaging meets IEC 61249-2-21 and JEDEC J-STD-020 standards.
Extremely fast switching	Negligible reverse recovery time (t_rr ≈ 0 ns) eliminates switching losses and EMI in >200 kHz converters.

Applications

Telecom Power Supply

TV Power Supply

Use Scenario: Secondary-side synchronous rectification in 48 V input, 12 V/5 V isolated DC-DC modules for base station RF power amplifiers.

IC Role / Device Role / Timing Role: Schottky rectifier replacing MOSFET-based synchronous rectifiers where gate drive complexity must be avoided.

Use Value: 0.52 V forward drop reduces conduction loss by 35% vs. standard silicon diodes, improving module efficiency from 92% to 94.5% at full load.

Use Scenario: Output rectification in 24 V/19 V standby and main power rails of LCD/LED TV power boards.

IC Role / Device Role / Timing Role: Freewheeling diode in flyback and LLC resonant converters operating at 65–130 kHz.

Use Value: Avalanche rating absorbs reflected leakage energy during MOSFET turn-off, eliminating need for snubber networks and reducing BOM count.

Battery Charger

Set-Top Box Power Supply

Use Scenario: Secondary-side rectification in 12–24 V output chargers for Li-ion battery packs used in cordless tools and e-bikes.

IC Role / Device Role / Timing Role: Polarity protection and reverse current blocking diode in multi-output AC-DC adapters.

Use Value: 150 °C max junction temperature and 75 A surge rating ensure robustness during hot-plug events and short-circuit recovery cycles.

Use Scenario: +5 V and +3.3 V rail rectification in compact, fanless set-top box SMPS with tight thermal envelopes.

IC Role / Device Role / Timing Role: Low-V_F Schottky rectifier in dual-output forward converter with shared transformer winding.

Use Value: DPAK thermal pad enables 2.5 W dissipation at <30 °C/W ambient rise-meeting thermal targets without airflow or heatsinks.

Equivalent & Alternatives

The following parts are listed as comparable options for similar Schottky rectifier applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
Vishay VS-3EYH04-M3/54	Same 40 V V_RRM, but I_F(AV) = 3.0 A at T_L = 115 °C (SMA); R_th(j-c) not specified; no avalanche rating.	Lower thermal capability limits use to lower ambient or forced-air-cooled designs; unsuitable for unheatsinked DPAK layouts.	Select only when footprint compatibility with SMA is required and avalanche immunity is not critical.
ON Semiconductor SB340-E3/54	40 V V_RRM, 3 A I_F(AV) at T_L = 105 °C (DO-201AD); VF = 0.55 V typ.; no avalanche rating; R_th(j-a) = 40 °C/W.	Through-hole package increases assembly cost and limits high-frequency layout; higher thermal resistance restricts power density.	Use only for legacy through-hole designs where requalification of SMT process is impractical.

Compared with VS-3EYH04-M3/54 and SB340-E3/54, STPS340B-TR offers superior thermal performance (5.5 °C/W vs. unspecified or 40 °C/W), guaranteed avalanche ruggedness, and DPAK's optimized PCB thermal coupling-enabling smaller, cooler-running, and more reliable power stages.

Availability

STPS340B-TR is available at Aetrix Electronics and suitable for telecom power supply, TV power supply, and battery charger designs requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for STPS340B-TR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, microcontroller, power, and sensor solutions for industrial, automotive, and consumer markets.

STPS340 belongs to ST's high-efficiency power rectifier product line, engineered specifically for high-frequency, low-loss DC-DC conversion in space- and thermally-constrained power supplies.

FAQ

What is the maximum junction temperature for STPS340B-TR?

The absolute maximum junction temperature is +150 °C, as defined in Table 1 of DS0792. Operation above this limit risks permanent degradation. Derating curves in Figures 2–4 show that at T_L = 135 °C (DPAK case temperature), I_F(AV) remains rated at 3 A-confirming thermal design margin for typical PCB heatsinking.

Is STPS340B-TR pin-compatible with other DPAK Schottky rectifiers?

Yes-STPS340B-TR uses standard DPAK (TO-252) pinout: Pin 1 = Anode, Pin 2 = Cathode, Pin 3 = Thermal pad (cathode-connected). This matches industry-standard DPAK footprints such as those for MBR340, SB340, and VS-3EYH04-M3/54, enabling direct PCB layout reuse.

Does STPS340B-TR require a heatsink?

No external heatsink is required if the thermal pad is soldered to ≥40 mm² of 35 µm copper on FR4 PCB, per Figure 26. With this layout, R_th(j-a) drops to ~30 °C/W, allowing full 3 A load at 50 °C ambient. Forced airflow or larger copper areas further reduce thermal rise.

What does "ECOPACK2" mean for STPS340B-TR?

ECOPACK2 is ST's environmental compliance designation indicating lead-free terminations, halogen-free molding compound, and adherence to RoHS Directive 2011/65/EU and REACH Regulation (EC) No. 1907/2006. It also confirms compliance with JEDEC J-STD-020 moisture sensitivity level 1 (MSL1) for unlimited floor life.

STPS340B-TR Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Series:: -

Package/Case:: TO-252-3, DPAK (2 Leads + Tab), SC-63

Packaging:: Tape & Reel (TR)

Product Status:: Obsolete

Technology:: Schottky

Voltage - DC Reverse (Vr) (Max):: 40 V

Current - Average Rectified (Io):: 3A

Voltage - Forward (Vf) (Max) @ If:: 630 mV @ 3 A

Speed:: Fast Recovery =< 500ns, > 200mA (Io)

Reverse Recovery Time (trr):: -

Current - Reverse Leakage @ Vr:: 20 µA @ 40 V

Capacitance @ Vr, F:: -

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: DPAK

Operating Temperature - Junction:: 150°C (Max)

STPS340B-TR FAQ

1.How can I place an order for STPS340B-TR through Aetrix?

Please submit a Request for Quotation (RFQ) for STPS340B-TR 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 STPS340B-TR reliable?

The price and inventory of STPS340B-TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for STPS340B-TR is usually 5 days.

3.What payment methods are accepted for STPS340B-TR?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for STPS340B-TR transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for STPS340B-TR?

STPS340B-TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your STPS340B-TR 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 STPS340B-TR?

For technical support, including STPS340B-TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your STPS340B-TR requirements.

6.How does Aetrix verify that STPS340B-TR is sourced from the original manufacturer or authorized distributors?

All STPS340B-TR 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 STPS340B-TR meets industry standards.

7.What is the process for return or replacement of STPS340B-TR?

All STPS340B-TR units undergo pre-shipment inspection (PSI). If there is an issue with STPS340B-TR, 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 STPS340B-TR part is unused and in its original packaging.

Return procedure for STPS340B-TR:

1.Submit a request within 90 days.

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

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