company blog about Recycle ST Power Transistors:IGBTs,Power Bipolar,Power MOSFETs,PowerGaN,SiC MOSFETs

Recycle ST Power Transistors:IGBTs,Power Bipolar,Power MOSFETs,PowerGaN,SiC MOSFETs

Shenzhen Mingjiada Electronics Co., Ltd. has specialised in the electronic component recycling sector for many years and is a professional provider of inventory management and recycling services within the industry. We purchase genuine, original manufacturer products, obsolete stock, discontinued products and idle chips at highly competitive prices, helping businesses to quickly clear their inventory, recover capital and reduce warehousing and management costs.

Key Advantages of Our Recycling Services

Comprehensive Purchasing: No minimum purchase quantity required; we can provide quotations for everything from small batches of samples to full trays of stock;

Efficient Cash Settlement: Preliminary online valuation based on photographs; for bulk consignments, we can arrange on-site inspection; payment is settled immediately upon confirmation;

Suitable for a Wide Range of Sources: We accept unsold factory stock, discontinued project stock, clearance stock and brand-new, unused components;

Standardised Material Handling: The handling of recycled materials complies with relevant regulations; we have established comprehensive partnerships with component recycling channels to help businesses capitalise on idle assets and free up warehouse space.

Transaction Process

Submit Inventory List: Compile detailed component information (part number, quantity, batch, package type, condition, packaging) and send via WeChat, email or telephone;

Accurate Quotation: Our valuation team will swiftly verify the specifications based on market conditions and issue a formal quotation;

Confirm the transaction: Once both parties have reached an agreement, a recycling agreement is signed and delivery arrangements are made (collection from your premises or by courier);

Delivery and payment: Settlement is processed immediately following on-site inspection or receipt of the goods, ensuring prompt payment.

I. ST Power Bipolar Junction Transistors (BJTs)

Power bipolar junction transistors (BJTs) are classic current-controlled power devices and were among the first power transistors to be industrialised. Drawing on years of technical expertise, ST has developed a range of highly reliable and cost-effective bipolar junction transistor products, designed primarily for medium- and low-voltage, low-frequency, high-current steady-state operating conditions.

1. Core Operating Principle

Power bipolar junction transistors are bipolar conductive devices that rely on a base input to continuously control the current, driving the conduction and cutoff of the current between the emitter and collector; both electron and hole carriers participate in the conduction process. As current-driven, fully controlled devices, they require a continuous base drive current to maintain the on-state during operation and do not feature a gate voltage control structure.

2. Key Technical Characteristics

ST’s power bipolar transistors cover a wide voltage range, from 15 V to 1,700 V, and include products with both conventional and high-gain Darlington configurations, with current ratings ranging from several amperes to several hundred amperes. Their core advantages include low saturation voltage, low steady-state conduction losses at high currents, strong shock resistance, mature manufacturing processes, low cost, and reliability proven over decades in the market.

However, these devices have significant shortcomings: slow switching speeds, with operating frequencies typically below 50 kHz, making them unsuitable for high-frequency conversion applications; high drive losses, requiring a continuous base current and resulting in high power consumption in the drive circuit; and relatively high switching losses, with dynamic response speeds far inferior to those of MOSFETs and IGBTs. Consequently, they are gradually being replaced by newer power devices and are now retained only in traditional applications where they remain essential.

3. Core Application Scenarios

These are primarily used in traditional industrial control applications characterised by low frequency, low speed and high steady-state current, including low-frequency motor drives, line-frequency switching power supplies, relay drivers, industrial voltage regulation circuits, small-scale inverter equipment and audio power amplifier circuits. They are predominantly employed in consumer and low-end industrial equipment where switching frequency is not a requirement and cost control is a priority.

II. ST Power MOSFETs (Silicon-based)

Silicon-based power MOSFETs are ST’s most widely used and diverse range of medium- and low-voltage power devices. As voltage-controlled unipolar devices that rely solely on majority carriers for conduction, they have completely overcome the high-frequency limitations of bipolar transistors and are the mainstream devices for small- and medium-power high-frequency power electronic systems. ST offers a full range of power MOSFET products, including low-voltage, medium- and high-voltage, and super-junction types, covering both general-purpose and high-end industrial applications.

1. Core Operating Principles

Power MOSFETs are voltage-driven, fully controlled devices that regulate channel conduction and turn-off via a threshold voltage between the gate and source. Conductivity relies solely on electrons as the sole charge carrier, with no minority carrier recombination process, resulting in extremely fast switching response times. The devices feature extremely high input impedance and require virtually no drive current during steady-state operation, leading to highly simplified drive circuits and minimal power consumption.

2. Key Technical Characteristics

ST’s silicon-based power MOSFETs cover a voltage range of 20 V to 900 V, a current range from milliamperes to several hundred amperes, and operating frequencies from 100 kHz to several MHz, making them ideally suited for high-frequency conversion applications. Their core advantages include fast switching speed, extremely low switching losses, simple drive requirements, good thermal stability, strong immunity to interference, and no risk of secondary breakdown.

ST’s proprietary technologies include the SuperJunction CoolMOS and SupremMOS series, which significantly reduce the on-resistance (Rds(on)) through optimised chip architecture, thereby achieving lower conduction losses and higher power density. A limitation lies in the noticeable disadvantage in forward voltage drop under high-voltage conditions; in high-voltage, high-power applications above 600 V, conduction losses are higher than those of IGBT devices.

3. Core Application Scenarios

Widely used in small- and medium-power high-frequency power electronic equipment, these are core components in consumer electronics and telecommunications equipment. Typical applications include mobile phone adaptors, PC switching power supplies, server and telecommunications power supplies, DC-DC converters, low-voltage motor drives, smart home control systems, and automotive low-voltage power supply systems.

III. ST IGBT (Insulated-Gate Bipolar Transistor)

The IGBT is a composite power device that combines the advantages of MOSFETs and bipolar transistors, perfectly balancing the requirements of high-voltage, high-current and medium-to-high-frequency operation. It serves as the core component in medium- and high-voltage, high-power industrial power electronics systems. ST’s IGBT product range covers multiple application levels—including consumer, industrial, automotive and rail transport—and is suitable for a wide range of power and frequency conditions.

1. Core Operating Principles

The IGBT integrates the gate-voltage drive structure of a MOSFET with the high-current conduction structure of a bipolar transistor. The input side utilises a MOSFET structure to enable voltage-driven operation and low drive power consumption; the output side employs a bipolar conduction structure, which reduces high-voltage conduction voltage drop through minority carrier injection. It thus combines the high-frequency characteristics of unipolar devices with the low conduction loss advantages of bipolar devices.

2. Key Technical Characteristics

ST IGBTs cover a voltage range of 600 V to 6.5 kV and current ratings of up to several thousand amperes, making them suitable for ultra-high-power applications. Their operating frequencies typically range from several kHz to 50 kHz, making them suitable for medium- to high-frequency, high-power conversion scenarios. Their core advantages include extremely low conduction losses at high voltages and currents, high current density, high voltage withstand capability, simple drive requirements and excellent stability.

The device’s limitations include tailing current during the turn-off process, switching speeds lower than those of power MOSFETs and wide-bandgap devices, and a significant increase in switching losses under high-frequency conditions, making it unsuitable for MHz-level high-frequency applications. ST has launched specialised series tailored to different scenarios, such as high-speed IGBTs, low-loss IGBTs and automotive-grade IGBTs, balancing loss and frequency characteristics.

3. Core Application Scenarios

Focusing on medium- and high-voltage, high-power power electronics applications, including industrial variable-frequency motor drives, UPS (uninterruptible power supply) systems, industrial welding machines, induction heating equipment, photovoltaic and wind power inverters, electric vehicle control systems, rail transport traction converters, and high-voltage industrial voltage stabilisers.

IV. ST Power GaN (Gallium Nitride) Devices

GaN (gallium nitride) devices are third-generation wide-bandgap semiconductor devices. ST primarily promotes silicon-based GaN power devices, which are suited to high-frequency, high-efficiency and miniaturised power conversion applications. These devices have broken through the frequency and efficiency limits of silicon-based devices and are the core components for upgrading high-frequency, medium-to-low-power high-end power supplies.

1. Core Operating Principles

ST’s GaN power devices are enhancement-mode voltage-controlled devices. Leveraging the high electron mobility characteristics of the wide-bandgap GaN material, they do not require the PN-junction conduction structure found in silicon-based devices. Instead, they rely on a two-dimensional electron gas (2DEG) to achieve high-speed conduction. Their carrier mobility and saturation drift velocity far exceed those of silicon, enabling switching response times in the nanosecond range.

2. Key Technical Characteristics

ST’s GaN devices are primarily available in 100 V and 650 V voltage ratings, offering outstanding core advantages: switching speeds far exceed those of silicon-based MOSFETs, with operating frequencies reaching tens of MHz, resulting in significantly reduced switching losses; on-resistance is extremely low, yielding on-state losses superior to those of silicon-based devices of the same specification; the devices are smaller in size and offer significantly higher power density, enabling the miniaturisation and weight reduction of power supply equipment.

Compared to silicon-based devices, GaN devices offer greater resistance to high temperatures and high-voltage breakdown, with reverse recovery losses approaching zero, thereby completely resolving the issue of reverse losses under high-frequency operating conditions. Their drawbacks include higher costs than silicon-based devices, stricter requirements for drive circuit precision, and more demanding constraints on PCB layout and process design.

3. Core Application Scenarios

These devices are primarily targeted at high-frequency, high-efficiency, and miniaturised high-end power conversion applications, including high-end fast-charging power supplies, high-frequency server power supplies, telecommunications base station power supplies, on-board chargers (OBCs) for vehicles, high-frequency DC-DC converters, lightweight new energy power supplies, and small-scale power equipment for the aerospace sector.

V. ST SiC MOSFET (Silicon Carbide)

SiC (silicon carbide) MOSFETs are currently the premier wide-bandgap devices in the high-voltage, high-power sector. ST has developed a comprehensive range of commercial SiC MOSFETs covering all medium- and high-voltage power ratings. Thanks to their ultra-high voltage withstand capability, ultra-low losses and high-temperature resistance, they are gradually replacing traditional silicon-based IGBTs to become the core components in high-end, high-power equipment for new energy applications.

1. Core Operating Principle

ST SiC MOSFETs are fabricated from 4H-SiC monocrystalline silicon carbide material and are unipolar voltage-controlled devices. They rely solely on electron carriers for conduction and are free from the minority carrier tailing effect, thereby completely resolving the switching loss bottleneck associated with silicon-based IGBTs. The material’s bandgap width, breakdown field strength and thermal conductivity are far superior to those of silicon, providing exceptional suitability for high-voltage, high-frequency applications.

2. Key Technical Characteristics

ST’s commercial SiC MOSFETs cover a voltage range of 650 V to 3,300 V, with prototype devices reaching up to 6,500 V, making them suitable for ultra-high-voltage, high-power applications. Their core characteristics include high breakdown field strength, high-temperature resistance and excellent thermal conductivity, enabling stable operation under high-temperature and harsh conditions; they feature extremely fast switching speeds, with switching losses amounting to less than one-third of those of silicon-based IGBTs; they exhibit extremely low conduction losses under high-voltage, high-current conditions, with overall energy efficiency far exceeding that of silicon-based devices.

Compared to GaN devices, SiC devices offer higher voltage ratings, superior high-temperature resistance and greater power capacity, making them ideal for high-voltage, high-power applications; their drawbacks include the highest device cost, stringent requirements for packaging and drive processes, and a relatively high barrier to system design.

3. Core Application Scenarios

Focusing on high-end, high-voltage, high-power, high-efficiency and high-reliability applications, these are core components in the new energy industry. Applications include main drive inverters for new energy vehicles, on-board high-voltage DC-DC converters, super-charging stations, large-scale photovoltaic and wind power inverters, energy storage PCS systems, high-voltage industrial variable-frequency equipment, rail transport traction systems, and high-end military power equipment.