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

Taiwan Semiconductor Corporation HER305G-K

Name: HER305G-K
Brand: Taiwan Semiconductor Corporation
SKU: HER305G-K
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: HER305G-K

Manufacturer:: Taiwan Semiconductor Corporation

Category:: Single Diodes

Package:: DO-201AD, Axial

Datasheet:: HER305G-K.pdf

Description:: 50NS, 3A, 400V, HIGH EFFICIENT R

Quantity:: RFQ Add To RFQ list

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Product details

Overview

HER305G-K from Taiwan Semiconductor is a high-efficiency, single-die, ultrafast recovery rectifier diode in DO-201AD package, rated for 400 V repetitive peak reverse voltage (V_RRM), 3 A average forward current (I_F), and 1.3 V forward voltage at 3 A and 25°C. It delivers 50 ns reverse recovery time (t_rr) and 60 pF junction capacitance at 1 MHz and 4.0 V reverse bias, suited for high-frequency switching power supplies.

For engineers reviewing the HER305G-K datasheet, HER305G-K pinout, HER305G-K application, or HER305G-K equivalent, key selection considerations include its 400 V V_RRM, 50 ns t_rr, DO-201AD mechanical compatibility, thermal resistance (R_θJL = 10 °C/W), and freewheeling performance in DC-DC converters.

Technical Context

This device operates as a unidirectional, single-junction silicon rectifier with ultrafast recovery characteristics optimized for high-frequency switching topologies. Its 50 ns t_rr and low Q_rr minimize switching losses during turn-off, while the 60 pF junction capacitance at 1 MHz/4.0 V supports stable high-speed waveform integrity.

The DO-201AD package provides robust thermal conduction (R_θJL = 10 °C/W) and mechanical reliability per JESD 201 Class 1A whisker testing. Cathode polarity is marked by a visible band, and terminals are pure tin-plated for J-STD-002 solderability.

Key Specifications

Parameter	Value and Actual Design Meaning
V_RRM	400 V - Maximum non-repetitive reverse voltage the diode blocks without breakdown; defines usable input voltage range in flyback or boost stages.
I_F	3 A - Continuous average forward current rating at case temperature ≤ 75°C; determines steady-state power handling capability.
t_rr	50 ns - Measured at I_F = 0.5 A, I_R = 1.0 A, I_rr = 0.25 A; enables operation up to ~2–3 MHz switching frequencies with low turn-off loss.
V_F	1.3 V @ 3 A, 25°C - Forward voltage drop under nominal load; directly impacts conduction loss and thermal design margin.
C_J	60 pF @ 1 MHz, V_R = 4.0 V - Junction capacitance affecting high-frequency noise coupling and snubber sizing in resonant circuits.
R_θJL	10 °C/W - Junction-to-lead thermal resistance; enables accurate heatsinkless thermal modeling when mounted on PCB copper pour.
I_FSM	125 A @ 8.3 ms half-sine - Surge current rating defining short-circuit and startup stress tolerance in SMPS primary-side rectification.

Pinout & Package

HER305G-K uses the DO-201AD axial-leaded package with cathode indicated by a colored band. Leads are pure tin-plated and compliant with J-STD-002 solderability requirements. The case meets UL 94V-0 flammability rating.

Pin/Terminal	Circuit Role	Design Meaning
Anode	Forward current entry point	Connected to lower-potential node (e.g., transformer secondary center-tap or switch node return); must sustain full I_F and I_FSM.
Cathode	Forward current exit / reverse blocking terminal	Marked by band; connects to output rail or filter capacitor positive; withstands full V_RRM during off-state.

Key Features

Feature	Design Value
Ultrafast recovery (50 ns)	Reduces reverse recovery charge (Q_rr) and associated switching losses in high-frequency converters (>100 kHz).
Low forward voltage (1.3 V @ 3 A)	Lowers conduction loss by ~15–20% vs. standard FR series, improving efficiency in 12–48 V output SMPS designs.
DO-201AD package with R_θJL = 10 °C/W	Enables direct PCB copper thermal relief without external heatsink for ≤2 W dissipation at ambient ≤60°C.
RoHS & halogen-free compliance	Meets IEC 61249-2-21 and EU RoHS Directive 2011/65/EU for environmentally constrained industrial and telecom applications.
JESD 201 Class 1A whisker resistance	Ensures long-term reliability of tin-plated leads under thermal cycling and humidity exposure in automotive-adjacent power modules.

Applications

DC-DC Converters	Switching Inverters
Use Scenario: Secondary-side synchronous rectification in isolated 24 V–48 V buck-derived DC-DC modules for server PSUs. IC Role / Device Role / Timing Role: High-efficiency freewheeling diode replacing Schottky in cost-sensitive designs where 400 V blocking is required. Use Value: 50 ns t_rr and 1.3 V V_F reduce total loss by 0.8–1.2 W per diode versus HER304G-K, lowering thermal stress on PCB layout.	Use Scenario: Output stage rectification in 1–3 kW solar microinverters operating at 50–100 kHz switching frequency. IC Role / Device Role / Timing Role: Unidirectional current path with fast turn-off to minimize dead-time conduction loss in H-bridge output filtering. Use Value: 60 pF C_J at 4 V bias ensures minimal capacitive feedthrough into gate drivers, preserving PWM fidelity.
Freewheeling Diodes	Industrial SMPS
Use Scenario: Inductive load flyback protection in PLC output driver modules driving solenoids and relays. IC Role / Device Role / Timing Role: Clamp diode absorbing L·di/dt energy during MOSFET turn-off in 24 V/3 A control outputs. Use Value: 125 A I_FSM rating handles repetitive 50 A surge peaks without degradation, extending field lifetime beyond 10 years.	Use Scenario: Primary-side auxiliary supply rectification in industrial AC-DC front-ends with universal 85–265 VAC input. IC Role / Device Role / Timing Role: High-reliability, high-V_RRM rectifier for bias winding output delivering 15 V/0.5 A to control ICs. Use Value: 150°C maximum junction temperature and -55°C to +150°C storage range support operation in sealed enclosures at 70°C ambient.

DC-DC Converters

Switching Inverters

Use Scenario: Secondary-side synchronous rectification in isolated 24 V–48 V buck-derived DC-DC modules for server PSUs.

IC Role / Device Role / Timing Role: High-efficiency freewheeling diode replacing Schottky in cost-sensitive designs where 400 V blocking is required.

Use Value: 50 ns t_rr and 1.3 V V_F reduce total loss by 0.8–1.2 W per diode versus HER304G-K, lowering thermal stress on PCB layout.

Use Scenario: Output stage rectification in 1–3 kW solar microinverters operating at 50–100 kHz switching frequency.

IC Role / Device Role / Timing Role: Unidirectional current path with fast turn-off to minimize dead-time conduction loss in H-bridge output filtering.

Use Value: 60 pF C_J at 4 V bias ensures minimal capacitive feedthrough into gate drivers, preserving PWM fidelity.

Freewheeling Diodes

Industrial SMPS

Use Scenario: Inductive load flyback protection in PLC output driver modules driving solenoids and relays.

IC Role / Device Role / Timing Role: Clamp diode absorbing L·di/dt energy during MOSFET turn-off in 24 V/3 A control outputs.

Use Value: 125 A I_FSM rating handles repetitive 50 A surge peaks without degradation, extending field lifetime beyond 10 years.

Use Scenario: Primary-side auxiliary supply rectification in industrial AC-DC front-ends with universal 85–265 VAC input.

IC Role / Device Role / Timing Role: High-reliability, high-V_RRM rectifier for bias winding output delivering 15 V/0.5 A to control ICs.

Use Value: 150°C maximum junction temperature and -55°C to +150°C storage range support operation in sealed enclosures at 70°C ambient.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
STTH3L04S	400 V V_RRM, 3 A I_F, 50 ns t_rr, but TO-220AC package (vs. DO-201AD); higher R_θJA (50 °C/W)	Requires heatsink for >1.5 W dissipation; unsuitable for space-constrained board layouts	Prefer HER305G-K for compact, heatsinkless designs; STTH3L04S only if thermal mass or mounting flexibility is prioritized.
ON Semi MUR3040	400 V V_RRM, 3 A I_F, 60 ns t_rr, DO-201AD package, but 1.5 V V_F @ 3 A (vs. 1.3 V)	Slightly higher conduction loss; same footprint and pinout	HER305G-K offers lower V_F and faster t_rr; MUR3040 may be selected only if dual-sourcing or legacy qualification mandates.

Compared with STTH3L04S and MUR3040, HER305G-K uniquely combines DO-201AD form factor, 1.3 V forward drop, and 50 ns recovery in a single RoHS/halogen-free device-making it optimal for thermally constrained, high-efficiency 400 V rectification where leaded axial mounting is acceptable.

Availability

HER305G-K is available at Aetrix Electronics and suitable for DC-DC converters, switching inverters, and freewheeling applications requiring stable component supply, consistent parametric performance across production lots, and long-term industrial lifecycle support.

Supply support for HER305G-K 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

Taiwan Semiconductor Corporation (TSC) is a vertically integrated analog and discrete semiconductor manufacturer headquartered in Hsinchu, Taiwan, serving global industrial, computing, and power electronics markets since 1979.

The HER30xG-K series was developed specifically for high-frequency, high-reliability rectification in switching-mode power supplies-emphasizing low V_F, fast t_rr, and robust thermal performance in axial-leaded packages.

FAQ

What is the maximum repetitive peak reverse voltage (V_RRM) for HER305G-K?

The HER305G-K has a specified V_RRM of 400 V, as confirmed in the Absolute Maximum Ratings table of the official Taiwan Semiconductor datasheet (Version C2105). This value is fixed for the HER305G-K variant and distinguishes it from adjacent family members like HER304G-K (300 V) and HER306G-K (600 V). Exceeding 400 V risks irreversible avalanche breakdown.

What is the forward voltage (V_F) of HER305G-K under typical operating conditions?

The HER305G-K exhibits a maximum forward voltage of 1.3 V when conducting 3 A at junction temperature of 25°C, per the Electrical Specifications table. At elevated temperatures (e.g., 125°C), V_F decreases slightly due to semiconductor physics, but system design should reference the 25°C max value for worst-case loss calculation. This V_F is measured using a 0.3 ms pulse test.

Does HER305G-K have a defined reverse recovery time (t_rr) and how is it measured?

Yes, HER305G-K has a maximum reverse recovery time of 50 ns, tested under conditions of I_F = 0.5 A, I_R = 1.0 A, and I_rr = 0.25 A, as documented in the Electrical Specifications section. This parameter is critical for minimizing switching losses in high-frequency converters and is verified using the test circuit shown in Figure 6 of the HER30xG-K datasheet.

What package type does HER305G-K use and what are its key mechanical attributes?

HER305G-K uses the DO-201AD axial-leaded package, with cathode polarity indicated by a visible band. Key attributes include UL 94V-0 mold compound, pure tin-plated leads compliant with J-STD-002, JESD 201 Class 1A whisker resistance, and a typical weight of 1.10 g. The package outline dimensions and marking diagram are provided in the final pages of the Taiwan Semiconductor datasheet.

Is HER305G-K suitable for automotive applications?

HER305G-K is not qualified to AEC-Q101 or automotive-grade reliability standards. While it operates across -55°C to +150°C and meets JESD 201 whisker testing, Taiwan Semiconductor explicitly states these devices are "not designed for use in medical, life-saving, or life-sustaining applications"-and automotive safety-critical systems fall under this exclusion. HER305G-K is intended for industrial, computing, and telecom power supplies.

HER305G-K Specifications

Product attributes: Attribute value

Manufacturer:: Taiwan Semiconductor Corporation

Series:: -

Package/Case:: DO-201AD, Axial

Packaging:: Tape & Reel (TR)

Product Status:: Active

Technology:: Standard

Voltage - DC Reverse (Vr) (Max):: 400 V

Current - Average Rectified (Io):: 3A

Voltage - Forward (Vf) (Max) @ If:: 1.3 V @ 3 A

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

Reverse Recovery Time (trr):: 50 ns

Current - Reverse Leakage @ Vr:: 10 µA @ 400 V

Capacitance @ Vr, F:: 60pF @ 4V, 1MHz

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: DO-201AD

Operating Temperature - Junction:: -55°C ~ 150°C

HER305G-K FAQ

1.How can I place an order for HER305G-K through Aetrix?

Please submit a Request for Quotation (RFQ) for HER305G-K 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 HER305G-K reliable?

The price and inventory of HER305G-K are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for HER305G-K is usually 5 days.

3.What payment methods are accepted for HER305G-K?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for HER305G-K transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for HER305G-K?

HER305G-K orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your HER305G-K 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 HER305G-K?

For technical support, including HER305G-K datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your HER305G-K requirements.

6.How does Aetrix verify that HER305G-K is sourced from the original manufacturer or authorized distributors?

All HER305G-K 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 HER305G-K meets industry standards.

7.What is the process for return or replacement of HER305G-K?

All HER305G-K units undergo pre-shipment inspection (PSI). If there is an issue with HER305G-K, 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 HER305G-K part is unused and in its original packaging.

Return procedure for HER305G-K:

1.Submit a request within 90 days.

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

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