STMicroelectronics

BUZ71A - 50V 13A N-Channel Power MOSFET | STMicroelectronics

N.º da peça: BUZ71A ✓ Ativo
Em estoque Enviado em 1 a 3 dias úteis
50 V Vdss 13 A Id 0.1 ohm Rds(on) TO-220 (TO-220AB) Package
A partir de $0.61 USD / unidade
MOQ: 1 |
Preço atualizado: 2026-10-20
Preços por volume
Qtd. Preço unitário Total
1 $1.2 $1,20
10 $1.02 $10,20
100 $0.85 $85,00
500 $0.72 $360,00
1.000 $0.61 $610,00
ℹ️ Todos os preços estão em USD

BUZ71A Visão geral

The STMicroelectronics BUZ71A is an N-channel 50V, 13A, 0.1 ohm (typical RDS(on)) StripFET power MOSFET in a TO-220 through-hole package, rated for 40W power dissipation and 175C operating junction temperature with 100% avalanche testing.

A power MOSFET is a voltage-controlled semiconductor switch that dominates the power-management layer of modern electronics. As an enhancement-mode N-channel device, it conducts when the gate is driven above the source and offers far higher switching speed and lower gate-drive power than bipolar transistors. Power MOSFETs sit within the broader hierarchy of discrete semiconductors: transistor family, field-effect transistor (FET) class, metal-oxide-semiconductor (MOS) technology, used wherever efficient load switching is required.

Key features of the BUZ71A include STStripFET cell geometry for low on-state resistance (0.1 ohm typical), avalanche-rugged technology that is 100% avalanche energy tested for inductive-load robustness, high continuous current capability of 13A at 25C case temperature, and a maximum operating temperature of 175C. Older Intersil and Motorola second sources specify 0.120 ohm maximum RDS(on) at 13A, confirming parametric equivalence across vendors.

The device uses an enhancement-mode silicon-gate vertical DMOS structure. The StripFET layout minimizes channel resistance and gate charge, enabling efficient switching in regulators and converters where both conduction and switching losses matter. Gate drive requirements are modest, allowing direct drive from logic-level circuitry with adequate voltage headroom.

Typical applications include switching regulators, switching converters, motor drivers, relay and solenoid drivers, and high-power bipolar transistor driver stages - exactly the application list cited in the manufacturer datasheet. It also fits general-purpose DC-DC bricks and lighting ballasts.

Design consideration: verify gate-drive amplitude against the gate threshold specification and add a gate series resistor to damp parasitic ringing; at 13A, even 0.1 ohm RDS(on) dissipates roughly 17W (estimated: I^2 x R = 13^2 x 0.1), so heatsinking on the TO-220 tab is essential at high duty cycles.

This page synthesizes distributor pricing, cross-referenced drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone.

Alternativas drop-in para BUZ71A — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.

Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:

BUZ71

✅ Drop-In
📦 TO-220
same 50V rating and G-D-S pinout; earlier cell structure, ID 18A rating but higher RDS(on) than A-version

📋 Alternativa de referência (fora do catálogo)

BUZ72A

✅ Drop-In
📦 TO-220
same BUZ family A-version, TO-220 G-D-S pinout; different RDS(on)/current grade within 30%

📋 Alternativa de referência (fora do catálogo)

BUZ74A

✅ Drop-In
📦 TO-220
same BUZ family, 50V class, pin-compatible; higher RDS(on) grade (up to 30% parametric difference)

📋 Alternativa de referência (fora do catálogo)

BUZ76A

✅ Drop-In
📦 TO-220
same family 50V-class TO-220, pin-compatible; higher current grade with different RDS(on)

📋 Alternativa de referência (fora do catálogo)

MTP3055VL

✅ Drop-In
📦 TO-220AB
60V vs 50V (+20% VDS), 12A vs 13A (-8% ID), higher RDS(on) class; listed as functional equivalent in cross-reference data

📋 Alternativa de referência (fora do catálogo)

BUZ71A

✅ Drop-In
STMicroelectronics
📦 TO-220AB
N-Channel · Enhancement mode · 50 V · 13 A · 0.1 ohm · 0.120 ohm at ID = 13 A · 40 W

✓ Em estoque

$0.61 / unidade

Ver ficha técnica →

BUZ71A Classificações máximas e características elétricas

Polarity N-Channel
Operating Mode Enhancement mode
Drain-Source Voltage (VDS) 50 V
Continuous Drain Current (ID) 13 A
RDS(on) Typical 0.1 ohm
RDS(on) Maximum (per Intersil/Motorola data) 0.120 ohm at ID = 13 A
Power Dissipation (Pd) 40 W
Avalanche Test 100% avalanche tested
Technology STripFET
Temperatura de junção de operação -55C to +175C
Encapsulamento TO-220 (TO-220AB)
Tipo de montagem Through Hole
Contagem de pinos 3
Configuration Single MOSFET (1 element)
Typical Applications Switching regulators, converters, motor/relay drivers

Configuração de pinos do BUZ71A

TO-220 Package Pinout Diagram TO-220 3-pin vertical mount with tab, JEDEC. 1 2 3 TO-220
Pino 1 Gate — Gate control terminal; drive with 10V for full enhancement
Pino 2 Drain — Drain terminal, connected to the metal mounting tab
Pino 3 Source — Source terminal; reference for gate drive

Aplicações típicas

BUZ71A é adequado para 6 aplicaçãos: Switching Regulators, Switching Converters (DC-DC), Motor Drivers, Relay and Solenoid Drivers, Driver for High-Power Bipolar Switching Transistors, Audio Amplifier Power Supply Repair.

⚡

Switching Regulators

The BUZ71A is explicitly listed in the manufacturer datasheet as designed for switching regulators, where it acts as the main PWM switch. Its 0.1 ohm typical RDS(on) keeps conduction losses low during the on-phase, while STripFET technology limits gate charge so switching transitions are fast, reducing overlap losses at typical 20-200 kHz regulator frequencies. The 50V VDS rating comfortably covers 24V industrial buses with transient margin, and the 100% avalanche test provides robustness against leakage-inductance spikes on the switching node. Designers should include a snubber or clamp and verify gate drive of about 10V to achieve full enhancement and datasheet-level RDS(on).

🔌

Switching Converters (DC-DC)

In DC-DC switching converters, the BUZ71A serves as the primary-side or synchronous switch where 50V blocking and 13A capability align with 12V/24V input brick converters. The low 0.1 ohm RDS(on) means an estimated 17W conduction loss at full 13A (I^2 x R), so heat spreading via the TO-220 tab and heatsink is required at high duty cycle. Avalanche ruggedness absorbs transformer leakage energy, and the 175C junction rating gives thermal headroom in sealed enclosures. A gate driver delivering 10-12V with a small series resistor minimizes switching loss and damps ringing for efficient, reliable conversion.

🏭

Motor Drivers

For DC motor control, the BUZ71A functions as a low-side PWM switch or as part of an H-bridge leg. Its 13A continuous rating covers most 12V/24V fractional-horsepower motors, and the 100% avalanche energy test protects against the repetitive inductive kick from motor windings when the device switches off. Low RDS(on) of 0.1 ohm typical reduces voltage drop and heating during long on-times, which matters in stalled-rotor conditions. Add a flyback diode or TVS across the motor terminals, drive the gate with 10V for minimum on-resistance, and size the heatsink for worst-case stall current to keep junction temperature safely below 175C.

🔧

Relay and Solenoid Drivers

The BUZ71A is well suited to driving relays and solenoids from microcontroller or logic systems. The MOSFET presents a purely capacitive gate load, so drive power is negligible compared with bipolar alternatives such as the TIP120 Darlington, which needs a base resistor and dissipates about 1.4V of saturation drop. With 0.1 ohm RDS(on), the BUZ71A drops an estimated 1.3V at 13A - roughly an order of magnitude less loss. The avalanche-tested die tolerates coil de-energization spikes, though a clamp diode is still recommended. A gate series resistor of a few hundred ohms limits inrush into the gate capacitance from the GPIO pin.

🖥️

Driver for High-Power Bipolar Switching Transistors

The manufacturer datasheet specifically cites the BUZ71A for driving high-power bipolar switching transistors requiring high speed and low gate-drive power. In this topology, the MOSFET acts as a fast pre-driver that abruptly removes base drive from a BJT switch, sharply reducing storage time and improving overall converter efficiency. The BUZ71A's low gate charge and 0.1 ohm RDS(on) allow rapid charge extraction with minimal dissipation, while the 50V rating withstands the driver-rail transients typical of such stages. This arrangement appears in legacy switching power supplies and inverters being serviced or rebuilt with available TO-220 components.

🎧

Audio Amplifier Power Supply Repair

Repair communities frequently replace the BUZ71/BUZ71A family in audio amplifier switch-mode power supplies, as documented in repair forum threads. The BUZ71A's 50V, 13A, 0.1 ohm ratings match the demands of half-bridge and forward converter stages in hi-fi power supplies, where low RDS(on) reduces heat buildup in confined chassis. Because the TO-220 footprint and G-D-S pinout are standard, replacements such as BUZ72A or onsemi MTP3055VL can be fitted without PCB rework, though gate resistors should be checked when moving between MOSFET generations with different gate charge. Match devices from the same batch in push-pull stages for balanced switching.

Resumo dos produtos recomendados

LM2576D-ADJRG HANSCHIP Usado em: Switching Regulators UC3842 Current-mode PWM controller driving the gate Usado em: Switching Regulators SG3525 PWM controller for push-pull converter gate drive Usado em: Switching Converters (DC-DC) MBR20100CT Schottky rectifier for converter output stage Usado em: Switching Converters (DC-DC) L298 Dual H-bridge driver for complementary motor control Usado em: Motor Drivers 1N5822 Flyback freewheeling diode across motor terminals Usado em: Motor Drivers 1N4007 Flyback diode across relay coil Usado em: Relay and Solenoid Drivers TLP250 Optocoupled gate driver for isolation Usado em: Relay and Solenoid Drivers TIP41C STMicroelectronics Usado em: Driver for High-Power Bipolar Switching Transistors TL494 PWM control IC for the converter stage Usado em: Driver for High-Power Bipolar Switching Transistors TL431 Secondary-side voltage reference for feedback Usado em: Audio Amplifier Power Supply Repair PC817 Optocoupler for feedback isolation Usado em: Audio Amplifier Power Supply Repair
What are the key specifications of the BUZ71A MOSFET?
The BUZ71A is an N-channel enhancement-mode power MOSFET rated 50V VDS, 13A continuous drain current, with 0.1 ohm typical RDS(on) (0.120 ohm max per second-source data), 40W power dissipation, and 175C maximum junction temperature. It is built on STMicroelectronics STripFET technology and is 100% avalanche energy tested. According to the STMicroelectronics datasheet, it comes in a 3-pin TO-220 package.
What is the pinout of the BUZ71A in TO-220 package?
The BUZ71A uses the standard TO-220 power MOSFET pinout: pin 1 is the Gate, pin 2 is the Drain (also connected to the metal tab), and pin 3 is the Source. This G-D-S ordering is shared by virtually all TO-220/TO-220AB power MOSFETs, which is why same-pinout devices such as BUZ71, BUZ72A, and onsemi MTP3055VL can be dropped onto the same PCB footprint. Always confirm against the manufacturer datasheet before substitution.
What is the best drop-in replacement for BUZ71A?
The closest drop-in replacements are the same-family ST parts BUZ71 (50V, 18A) and BUZ72A, which share the identical TO-220 G-D-S pinout and voltage class. Cross-brand, the onsemi MTP3055VL (60V, 12A, TO-220AB) is listed as a functional equivalent in cross-reference databases, and New Jersey Semiconductor manufactures its own BUZ71A under the same part number. All four mount on the same footprint without PCB changes.
Can MTP3055VL replace BUZ71A?
Yes, in most general-purpose switching applications the onsemi/ST MTP3055VL (60V, 12A, 0.150-0.175 ohm class RDS(on), TO-220AB) can replace the BUZ71A (50V, 13A, 0.1-0.12 ohm). It is pin-compatible and offers higher voltage margin but lower current rating (-8%) and higher on-resistance, so conduction losses rise. For designs running near 13A continuously or needing minimum RDS(on), prefer the ST BUZ71/BUZ72A family instead.
What is the difference between BUZ71A and BUZ71?
The BUZ71A is the improved A-suffix version of the BUZ71: both are ST N-channel 50V TO-220 MOSFETs, but the BUZ71A uses STripFET technology with 0.1 ohm typical RDS(on), while the BUZ71 is specified at 18A with earlier-generation cell structure and higher on-resistance. The A version offers lower conduction losses at the same 50V rating and identical pinout, making it the preferred choice for new designs and repairs.
What is the price of BUZ71A and where can I buy it online?
As of 2026-10-21, BUZ71A pricing on XAIPART starts at approximately USD 1.20 for 1 piece, dropping to about USD 0.61 at 1000 pieces. Distributors such as Mouser, Win Source, and Octopart-listed suppliers (6 distributors per Octopart) also carry stock or accept RFQs. Availability varies by region, so request a quote for volume pricing and current lead time before committing a production BOM.
Is BUZ71A in stock, and what is the typical lead time?
Stock status for BUZ71A changes frequently because it is an older TO-220 part carried by a limited number of distributors. Octopart currently lists 6 distributors offering the ST part, and secondary sources such as New Jersey Semiconductor provide same-spec alternatives. On XAIPART, quote-based ordering applies; expect typical distributor lead times of a few days to several weeks depending on quantity. Always confirm live stock at checkout as of your order date.
Is BUZ71A suitable for a motor driver or relay driver circuit?
Yes. The manufacturer datasheet explicitly targets switching regulators, switching converters, motor drivers, and relay drivers. The 50V VDS provides margin over 12V and 24V rails, the 13A rating covers most small DC motors and relay coils, and the 100% avalanche energy test provides ruggedness against inductive kickback from motor windings and relay coils. Still add a flyback diode or TVS across inductive loads for maximum reliability.
Can BUZ71A be driven directly from an Arduino or microcontroller GPIO?
Partly: the BUZ71A is not a logic-level MOSFET, so it may not fully enhance at 5V gate drive, increasing RDS(on) and heat at high currents. Community experience (e.g., Arduino project discussions) shows it can switch small loads from 5V GPIO with a series gate resistor, but for full 13A capability you should drive the gate with 10V (or add a gate driver such as a MOSFET driver IC). For 5V-only designs, choose a logic-level MOSFET instead.
How much power does the BUZ71A dissipate at 10A load?
Estimated: with 0.1 ohm typical RDS(on), conduction loss at 10A is P = I^2 x R = 100 x 0.1 = 10W. At 13A it rises to roughly 17W. The TO-220 package dissipates 40W only with an adequate heatsink keeping the case near 25C; a bare part in free air handles only a few watts. Size the heatsink so junction temperature stays below 175C with margin - practically below 125C for reliability.
Where can I download the BUZ71A datasheet PDF?
The BUZ71A datasheet PDF from STMicroelectronics (8 pages, describing the N-channel 50V, 0.1 ohm, 13A STripFET power MOSFET) is available via the link on this page, hosted by alldatasheet.com. Equivalent datasheets exist from second sources: Intersil (6 pages, 13A, 50V, 0.120 ohm) and Motorola/Philips (12A, 50V, 0.12 ohm, TO-220AB). The ST version is authoritative for the current-manufactured part.
What is the best STMicroelectronics equivalent for BUZ71A if it goes out of stock?
Within STMicroelectronics, the best equivalents are BUZ72A and BUZ74A from the same BUZ TO-220 family - all share the standard G-D-S pinout and 50V-class ratings. Choose BUZ72A when similar current capability is needed; choose higher-current family members like BUZ76A for extra margin. Verify RDS(on) and gate threshold against your gate-drive voltage before substitution, since the BUZ family spans several RDS(on) and current grades.
BUZ71A vs IRF530/IRF540 - which should I choose?
Choose the BUZ71A when you want a proven 50V, 13A, 0.1 ohm STripFET part with avalanche testing and low cost for regulators, converters, and relay drivers. Choose IRF-series parts (International Rectifier/Infineon) when you need broader second-source availability or higher voltage classes, noting that classic IRF530/IRF540 also require 10V gate drive. All are TO-220, pin-compatible G-D-S devices, so PCB reuse is straightforward - the deciding factors are RDS(on), gate charge, and sourcing.
Is the BUZ71A RoHS compliant and lead-free?
Compliance data for the BUZ71A was not confirmed in the sources reviewed as of 2026-10-21, so RoHS and REACH status should be verified on the official STMicroelectronics product page or the distributor certificate of conformance (CoC) before use in EU-market products. Because the part remains an active ST listing, current production is typically RoHS-compliant and lead-free, but do not rely on assumption - request the CoC from your supplier for documentation.
Is the BUZ71A obsolete? What is its lifecycle status?
The BUZ71A remains listed as an active STMicroelectronics part with 6 distributors offering it on Octopart as of October 2026, and second sources such as New Jersey Semiconductor actively supply it. It is a legacy TO-220 device - not recommended for brand-new cutting-edge designs - but it is widely available for maintenance and repair of existing equipment such as audio amplifiers and power supplies. For new designs, consider newer ST SuperMesh or stripFET generations.

Dados de referência de engenharia para BUZ71A — comparação, orientação de projeto e informações de conformidade.

Guia de seleção

Choose the BUZ71A when you need a rugged, low-RDS(on) 50V N-channel MOSFET for switching regulators, converters, motor, or relay drivers and can provide ~10V gate drive and adequate heatsinking. Within the ST family, pick BUZ71 for legacy stock compatibility, BUZ72A or BUZ74A if parametric grades better fit your RDS(on)/current needs, and BUZ76A when extra current margin is required - all share the same TO-220 footprint. Choose onsemi MTP3055VL when a 60V rating matters more than minimum on-resistance and when sourcing BUZ parts is difficult; it costs some conduction efficiency (higher RDS(on), 12A vs 13A). For brand-new 5V-driven designs, consider a modern logic-level MOSFET instead, since the BUZ71A is only partially enhanced at 5V gate drive.

Comparação com alternativas

Parâmetro Este produto BUZ71 BUZ72A MTP3055VL BUZ71A (NJS)
Package TO-220 (ST) TO-220 - same TO-220 - same TO-220AB - same footprint TO-220AB - same footprint
Brand STMicroelectronics STMicroelectronics STMicroelectronics onsemi NJS (New Jersey Semiconductor)
Drain-Source Voltage 50 V 50 V 50 V 60 V 50 V
Max Junction Temperature 175 C 175 C 175 C 175 C 175 C

Principais diferenciais

  • Lowest RDS(on) in its 50V TO-220 peer group (vs MTP3055VL)
  • 100% avalanche energy tested (vs MTP3055VL)
  • Higher current rating within same ST family (vs BUZ71A (NJS second source))
  • Trade-off: not logic-level (vs Modern logic-level MOSFETs)

Notas de projeto

Estimated: at 13A continuous with 0.1 ohm RDS(on), conduction loss is about 17W, requiring a substantial heatsink since the TO-220 case must stay near 25C to sustain the 40W rating. Practically, target junction temperature below 125C: with a typical 2-3 C/W heatsink plus interface, a 17W dissipation demands forced air or a large extruded heatsink. For compact designs, reduce continuous current to 5-8A or lower the duty cycle, and use thermal paste rather than dry mounting on the tab.

The BUZ71A is a through-hole TO-220, so minimize gate loop area by placing the driver close to pin 1 and add a 100 ohm (typical) series gate resistor to damp ringing against gate capacitance. Keep the source return path (pin 3) directly to the driver ground to prevent source-lead inductance from slowing switching. For higher current paths, reinforce the drain/source traces with solder or wire links, since 13A exceeds the capability of a standard 1oz 2mm trace.

The BUZ71A is not a logic-level MOSFET: driving it from a 5V GPIO at high current leaves it partially enhanced, raising RDS(on) far above 0.1 ohm and causing overheating. Use a 10-12V gate drive or a gate driver IC. Also note the drain is bonded to the tab - isolated hardware is needed when mounting to a live heatsink. Handle with ESD precautions; silicon-gate MOSFETs are sensitive to gate oxide damage from static discharge.

Informações de conformidade

RoHS
Unknown
REACH
Unknown
AEC-Q100
Not Applicable
Sem chumbo
Unknown
Sem halogênios
Unknown
Minerais de conflito
Unknown

Compliance status was not stated in the reviewed sources as of 2026-10-21. Verify RoHS/REACH on the official STMicroelectronics product page or request a certificate of conformance from the distributor.

Dados verificados em: 2026-10-21 — dados verificados e curados pela equipe de engenharia de componentes da XAIPART

Buscas relacionadas

BUZ71A datasheet BUZ71A STMicroelectronics MOSFET BUZ71A equivalent substitute BUZ71A vs MTP3055VL 50V 13A N-channel MOSFET TO-220 BUZ71A pinout gate drain source BUZ71A price buy BUZ71A drop-in replacement BUZ71A motor driver switching regulator can BUZ71A replace BUZ71 BUZ71A logic level gate drive 5V STripFET power MOSFET avalanche tested

Componentes & termos relacionados

STMicroelectronics BUZ71A BUZ71 BUZ72A BUZ74A BUZ76A MTP3055VL NJS (New Jersey Semiconductor) power MOSFET N-channel enhancement mode MOSFET field-effect transistor discrete semiconductor STripFET TO-220 TO-220AB RDS(on) avalanche rugged technology VDS (drain-source voltage) gate threshold voltage switching regulator motor driver relay driver through-hole mounting
RFQ de cotação rápida
Preencha todos os detalhes — nossa equipe de vendas responderá em até 24 horas
Part number Fabricante Encapsulamento QTY Preço-alvo Total
Total: $0.00 USD
✓
Cotação enviada!

Responderemos seu e-mail em até 24 horas

1
RFQ enviada
2
Cotação recebida
3
Pedido realizado
4
Pagamento
5
Enviado
6
Entregue
Ver detalhes da RFQ