FQD6N25TM - 250V 4.4A N-Channel QFET MOSFET | onsemi
料号： FQD6N25TM ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $0.62 | $0.62 |
| 10 | $0.54 | $5.40 |
| 100 | $0.42 | $42.00 |
| 500 | $0.34 | $170.00 |
| 1,000 | $0.28 | $280.00 |
FQD6N25TM 概述
A MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) is a voltage-controlled three-terminal device in which the gate voltage modulates the conductivity of a channel between drain and source. Power MOSFETs such as the FQD6N25TM belong to the discrete semiconductor family and sit within the broader taxonomy: power MOSFET -> MOSFET -> field-effect transistor -> discrete semiconductor -> semiconductor. Their key advantages over bipolar transistors include high input impedance, fast switching, and no minority-carrier storage time, which makes them the workhorse of modern switch-mode power supplies.
Key features include a 250 V VDS rating that provides ample headroom for 110-220 V rectified off-line applications, a continuous ID of 4.4 A at TC with pulsed capability well above this, an ultra-low RDS(on) of 1.0 ohm at VGS = 10 V to minimize conduction losses, and a typical gate charge of 6.6 nC that reduces drive losses at high frequency. The TO-252AA surface-mount footprint with an exposed drain tab supports 2.5 W dissipation at TA and 45 W at TC, and the device is RoHS compliant.
The FQD6N25TM uses onsemi's planar stripe DMOS process technology, which trades slightly higher specific on-resistance for lower cost and excellent ruggedness. Its avalanche-rated single-pulse energy and dv/dt tolerance make it suitable for snubberless switching topologies, while the intrinsic body diode supports use in half-bridge and synchronous-rectifier-replacement circuits where a dedicated Schottky is not present.
Typical applications include AC-DC flyback and forward converters, solid-state relay (SSR) outputs, motor control drivers, and general-purpose low-side switches. Designers select this part where the 250 V rating provides margin against voltage transients on rectified mains rails, and where 4.4 A continuous current is sufficient without active cooling.
When designing with this part, ensure the gate drive swing reaches at least 10 V to fully enhance the channel and achieve the rated 1.0 ohm RDS(on); a 12 V gate drive is recommended for best performance. Provide adequate copper area on the drain tab to keep junction temperature below 150 C under worst-case load, and consider an external TVS or snubber for highly inductive loads to stay within the device's avalanche rating.
This page synthesizes distributor pricing, drop-in alternatives from multiple manufacturers, and practical design notes that go beyond the raw manufacturer datasheet, giving engineers a single consolidated reference for sourcing, substitution, and circuit design with the FQD6N25TM.
直接替换替代料： FQD6N25TM ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
快速对比工具——选择替代料号进行并排对比：
FQD6N25
✅ 直接替换📋 参考替代料（不在目录中）
NDD02N25
✅ 直接替换📋 参考替代料（不在目录中）
STD4NK50ZD
✅ 直接替换📋 参考替代料（不在目录中）
IRFR3711
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
RFD3055SM
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
FQD6N25TM 最大额定值与电气特性
| Manufacturer | onsemi (formerly Fairchild Semiconductor) |
| Part Number | FQD6N25TM |
| Technology | QFET (N-Channel enhancement-mode planar stripe DMOS) |
| Drain-Source Voltage (VDS) | 250 V |
| Continuous Drain Current (ID) | 4.4 A (Tc) |
| Static Drain-Source On-Resistance (RDS(on)) | 1.0 ohm at VGS = 10 V |
| Gate-Source Voltage (VGS) | +/- 30 V max (data range not in source) |
| Typical Gate Charge (Qg) | 6.6 nC |
| Power Dissition (TA) | 2.5 W |
| Power Dissipation (TC) | 45 W |
| 工作结温 | -55 C to +150 C |
| 封装 | TO-252AA (DPAK), surface mount |
| 安装类型 | Surface Mount |
| RoHS 状态 | Compliant |
| Lead-Free | Yes |
FQD6N25TM 引脚配置
| 引脚 1 | GATE — Gate control input (drive to +10 V to fully enhance) |
| 引脚 2 | DRAIN — Drain terminal (also electrically common with the exposed tab) |
| 引脚 3 | SOURCE — Source terminal (return for gate drive) |
安全工作区 (DC)
典型应用
FQD6N25TM 适用于 6 应用s: AC-DC Off-Line Flyback Converter, Solid-State Relay (SSR) Output Stage, Brushed DC Motor Driver (Low-Side), 48 V Telecom Hot-Swap Switch, Linear Mode LED Driver (Low-Side Switch), Battery Protection / Load Disconnect.
AC-DC Off-Line Flyback Converter
The FQD6N25TM fits the primary-side switch position in 110-127 V AC flyback converters where its 250 V VDS provides margin above the rectified 155-179 V bus plus inductive ringing transients, and its 4.4 A continuous drain current handles up to roughly 25 W of output power. In a typical 12 V/2 A flyback design, the FET operates at 65-100 kHz with a 12 V gate drive from a controller such as the NCP1014 or TinySwitch-LT family. Compared to a 400 V part, the FQD6N25TM delivers lower RDS(on) and lower gate charge, which reduces both conduction and switching losses at the cost of headroom against worst-case surge events.
推荐
Solid-State Relay (SSR) Output Stage
In AC-line solid-state relay outputs and DC switching modules, the FQD6N25TM is wired as a low-side switch between the load and ground, controlling resistive heating elements, lamps, or DC solenoids up to 4.4 A continuous. The 250 V VDS rating supports both 110 V AC and 24-200 V DC load voltages. A logic-level opto-isolator (MOC3021 or similar) provides 5 kV galvanic isolation between the control microcontroller and the FET gate. The 1.0 ohm RDS(on) contributes only modest self-heating, eliminating the need for an external heatsink for loads under 2 A.
推荐
Brushed DC Motor Driver (Low-Side)
For brushed DC motors and bidirectional solenoid drivers, the FQD6N25TM serves as the low-side switch in a half-bridge or full H-bridge topology. The 4.4 A continuous drain current drives small motors up to about 150 W mechanical, and the 1.0 ohm RDS(on) keeps conduction losses manageable. A flyback diode across the motor is essential to absorb inductive kickback - the FET's internal body diode is too slow for PWM operation above 1 kHz. Pair the FQD6N25TM with a gate driver such as the UCC27517 for fast 20-100 kHz PWM switching in closed-loop speed control.
推荐
48 V Telecom Hot-Swap Switch
In -48 V telecom distribution and 48 V industrial bus systems, the FQD6N25TM is well-suited as the main hot-swap FET because its 250 V VDS withstands -48 V plus full transient surges up to ~100 V, and its 4.4 A rating covers line-card inrush currents of several amps at startup. Place a current-sense resistor in series with the source and feed the voltage to a hot-swap controller (such as the LTC4210 or TPS2491) to provide inrush limiting and fault protection. The TO-252AA surface-mount package supports compact line-card designs.
推荐
Linear Mode LED Driver (Low-Side Switch)
For constant-current LED drivers in signage, architectural lighting, and industrial indicators, the FQD6N25TM operates in linear mode as a low-side current sink. The gate is driven from an op-amp error amplifier that senses a shunt resistor in series with the LED string and adjusts VGS to regulate current. The 250 V rating covers most LED strings up to 72 V, and the 4.4 A continuous rating handles currents up to about 4 A per string. Compared to a switching driver, this linear approach eliminates EMI and provides flicker-free dimming for sensitive applications.
推荐
Battery Protection / Load Disconnect
In multi-cell battery packs and DC power systems, the FQD6N25TM functions as a load-disconnect or charge-disconnect switch in series with the battery negative terminal (low-side configuration). Its 4.4 A continuous rating covers discharges up to about 50 W from a 12 V battery, and the 250 V VDS protects against load-dump transients in automotive 12 V systems. Drive the gate from a battery management IC such as the BQ29700 family, which provides overcurrent, overvoltage, and undervoltage protection. The TO-252AA package handles continuous current up to 2-3 A without an external heatsink in modest ambient temperatures.
推荐
推荐产品汇总
工程参考数据： FQD6N25TM ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | FQD6N25 | NDD02N25 | STD4NK50ZD |
|---|---|---|---|---|
| Package | TO-252AA (DPAK) | TO-252AA (DPAK) - same | TO-252AA (DPAK) - same | TO-252AA (DPAK) - same |
| Brand | onsemi | onsemi - same | onsemi - same | STMicroelectronics - cross-brand |
| Drain-Source Voltage (VDS) | 250 V | 250 V | 250 V | 500 V |
| Continuous Drain Current (ID) | 4.4 A | 4.4 A | 2.5 A | 3.0 A |
关键差异点
- Highest continuous drain current in this voltage class at DPAK （对比 NDD02N25 (onsemi))
- Lower RDS(on) than 500 V class alternatives （对比 STD4NK50ZD (STMicroelectronics))
- Proven QFET planar stripe DMOS technology （对比 FQD6N25 (TO-220 variant))
设计说明
Estimated: at VGS = 10 V and full rated load of 4.4 A continuous, the FQD6N25TM dissipates P = I^2 * R = 4.4^2 * 1.0 = 19.4 W, which exceeds the 2.5 W TA rating without heatsinking. With the TO-252AA tab soldered to a 1 square inch of 2 oz copper on a 1 oz FR-4 board, theta JA drops to about 50 C/W, allowing ~2 W dissipation at 25 C ambient. For continuous 4.4 A operation, attach an external clip-on heatsink to the drain tab or operate below 2 A continuous without one. Never exceed TJ(max) = 150 C - derate by 25 C for industrial reliability and 50 C for automotive designs.
Route the gate trace directly from the driver output to pin 1 of the FQD6N25TM without passing near the drain tab. Keep the gate-source loop area small (under 1 cm^2) to minimize parasitic inductance that could cause gate ringing and dv/dt-induced turn-on. Place a 10 ohm gate-source resistor close to the FET to damp the gate loop and prevent Miller-effect-induced turn-on in half-bridge circuits. Connect the source sense (if used) with a Kelvin connection to pin 3, not the tab, for accurate current sensing.
Do not exceed VGS = +/-20 V absolute maximum, even though +/-30 V is sometimes quoted - operation outside +/-20 V accelerates gate-oxide degradation. Do not rely on the internal body diode for hard-switched half-bridge operation above 1 kHz - its reverse recovery time is too slow and will cause shoot-through; use a co-packaged MOSFET with a Schottky diode or external anti-parallel diode. Do not forget the VGS(th) minimum gate drive - the FQD6N25TM is not a logic-level FET and requires at least 6-8 V VGS to fully enhance; 10 V is recommended for rated RDS(on).
The TO-252AA drain tab is the primary thermal path and must be soldered to a copper pad of at least 50 mm^2 per mm^2 of tab area on the PCB. Use multiple thermal vias (typically 4-8 of 0.3 mm diameter) under the tab to conduct heat to the bottom-side copper plane, which can act as a heatsink. For TO-252AA parts in high-current designs (>2 A continuous), follow JEDEC JESD51 thermal measurement standards and provide at least 100 mm^2 of copper on the drain tab for adequate thermal performance.
合规信息
RoHS and lead-free compliance confirmed by onsemi datasheet markings. AEC-Q100 not qualified - for automotive applications use an AEC-Q100 qualified equivalent such as NVHL072N120SC1 (where applicable). Halogen-free status not confirmed in source data.
