FDS9435A - 30V P-Channel PowerTrench MOSFET | onsemi
料号： FDS9435A ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $0.86 | $0.86 |
| 10 | $0.74 | $7.40 |
| 100 | $0.58 | $58.00 |
| 500 | $0.46 | $230.00 |
| 1,000 | $0.38 | $380.00 |
FDS9435A 概述
A P-Channel MOSFET (PMOS) is a type of metal-oxide-semiconductor field-effect transistor in which the channel is formed by holes rather than electrons. In the broader semiconductor taxonomy, it belongs to the MOSFET family, which itself sits under discrete semiconductors and power management devices. P-Channel MOSFETs are typically used for high-side load switching because the source is tied to the system supply and the device is turned on by pulling the gate below the source potential, simplifying gate-drive design when the system controller already has a low-voltage reference.
Key features of the FDS9435A include a low on-resistance of 50 milliohms at VGS = 10V and 80 milliohms at VGS = 4.5V, plus the rugged-gate construction that withstands 4.5V to 25V gate drive. The PowerTrench cell architecture reduces Rds(on) per unit silicon area, and the 8-SOIC footprint allows standard surface-mount assembly. Together, these characteristics make the FDS9435A suitable for low-voltage DC load switching and small-signal power management where a rugged gate is required.
The PowerTrench process uses a proprietary shielded-gate trench structure that minimizes cell pitch and reduces conduction losses versus older planar MOSFET generations. This translates into lower Rds(on) for the same die size, enabling higher efficiency in switching applications, or smaller PCB area for the same efficiency. The P-channel polarity is complementary to the more common N-channel MOSFET and simplifies circuit design in high-side switch topologies because the load can be returned to system ground.
Typical applications include high-side load switches in notebook and desktop computing, USB power distribution, battery protection circuits in portable equipment, and general low-voltage DC-DC conversion. The wide VGS rating (4.5V to 25V) also makes it suitable for motor drive and solenoid switching where the gate driver voltage is independent of the system logic supply.
When designing with this part, observe the 2.5W Ta power dissipation limit and provide adequate copper area on the PCB to keep the junction temperature within the rated maximum. The SO-8 footprint has a higher junction-to-ambient thermal resistance than larger packages (such as DPAK), so thermal vias or a copper pour are typically required for continuous high-current operation.
This page synthesizes distributor pricing, drop-in pin-compatible alternatives, and practical PCB layout notes for engineers evaluating the FDS9435A as a high-side switch candidate.
直接替换替代料： FDS9435A ——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：
FDS9435A-NL
✅ 直接替换📋 参考替代料（不在目录中）
NDS8434A
✅ 直接替换📋 参考替代料（不在目录中）
Si2333DDS
✅ 直接替换📋 参考替代料（不在目录中）
DMG2305UX-7
✅ 直接替换📋 参考替代料（不在目录中）
AO3401A
✅ 直接替换📋 参考替代料（不在目录中）
FDS9435A 最大额定值与电气特性
| FET Type | P-Channel |
| Drain-to-Source Voltage (VDS) | 30 V |
| Continuous Drain Current (ID) at Ta | 5.3 A |
| Power Dissipation (PD) at Ta | 2.5 W |
| Rds(on) at VGS = 10 V | 50 milliohms |
| Rds(on) at VGS = 4.5 V | 80 milliohms |
| Gate Drive Voltage Range (VGS) | 4.5 V to 25 V |
| Technology | PowerTrench (advanced shielded-gate trench) |
| 封装 | 8-SOIC (SO-8) |
| 安装类型 | Surface Mount |
| Operating Mode | Enhancement Mode |
| Polarity / Channel Type | P-Channel |
| Number of Channels | 1 |
| Process / Manufacturer Family | PowerTrench (onsemi / Fairchild Semiconductor) |
| RoHS 状态 | Compliant |
| Gate Construction | Rugged-gate version |
FDS9435A 引脚配置
| 引脚 1 | Source — Source terminal (connected to system supply) |
| 引脚 2 | Source — Source terminal (connected to system supply) |
| 引脚 3 | Source — Source terminal (connected to system supply) |
| 引脚 4 | Gate — Gate drive input |
| 引脚 5 | Drain — Drain terminal (load connection) |
| 引脚 6 | Drain — Drain terminal (load connection) |
| 引脚 7 | Drain — Drain terminal (load connection) |
| 引脚 8 | Drain — Drain terminal (load connection) |
安全工作区 (SOA) - FDS9435A
典型应用
FDS9435A 适用于 6 应用s: High-Side Load Switch in Notebook Computing, USB VBUS Power Distribution Switch, Battery Protection and Load Switching in Portable Equipment, Low-Voltage DC-DC Converter Synchronous Rectifier, Solenoid and Relay Driver Replacement, LED Matrix and Backlight Driver Switch.
High-Side Load Switch in Notebook Computing
The FDS9435A is well suited as a high-side load switch in notebook and ultrabook power distribution networks. Its P-channel configuration allows the gate to be driven directly from a 3.3V or 5V GPIO without a charge pump, simplifying the design around the EC (embedded controller). The 30V VDS rating provides ample headroom above 19V adapter rails and 12V internal rails, while 50 milliohm Rds(on) at VGS=10V keeps conduction losses under 0.3W at typical 2.5A load currents. Compared to N-channel high-side switches, the FDS9435A eliminates the need for a bootstrap capacitor and level-shifted gate driver, reducing BOM count and PCB area.
推荐
USB VBUS Power Distribution Switch
The FDS9435A works as a USB VBUS high-side distribution switch in laptops, hubs, and wall adapters. With a 5V VBUS rail and a 5.3A continuous drain current rating, the device comfortably exceeds USB 3.0 downstream port requirements (900mA per port) and supports multi-port ganged switching up to about 2.5A continuous. The 50 milliohm Rds(on) at VGS=10V keeps conduction losses around 25mW per port at 500mA, well within the SO-8 2.5W thermal envelope without additional heatsinking. The 30V VDS also protects against VBUS fault transients during hot-plug events.
推荐
Battery Protection and Load Switching in Portable Equipment
In portable battery-powered equipment such as power banks, e-readers, and handheld instruments, the FDS9435A serves as a P-channel high-side disconnect switch between the Li-ion cell stack (up to 4.2V per cell) and the system load. The 30V VDS supports 1S to 4S Li-ion packs with substantial transient margin, and the low Rds(on) minimizes the voltage drop between battery and load, preserving runtime. The wide 4.5V to 25V gate-drive window allows the gate to be pulled to the battery positive rail for off-state and to ground for on-state with no level-shifting circuitry required.
推荐
Low-Voltage DC-DC Converter Synchronous Rectifier
The FDS9435A can be deployed as the synchronous rectifier (low-side or high-side) in low-voltage buck converters operating from 5V to 24V rails. The PowerTrench process delivers low Rds(on) at both 10V and 4.5V gate drive, allowing the device to be driven directly from a 5V PWM controller output without a separate gate-drive supply. In a 12V-to-3.3V buck converter at 3A load, conduction losses in the FDS9435A synchronous FET are around 450mW (50 milliohm x 3A), which is within the SO-8 thermal envelope when mounted on a 1-square-inch copper pour.
推荐
Solenoid and Relay Driver Replacement
In industrial control and appliance applications, the FDS9435A can directly drive small solenoids, latching relays, and valves from a 12V or 24V supply, replacing mechanical relays with solid-state switching. The P-channel orientation allows the solenoid to be wired to ground (rather than the high-side rail), which simplifies wiring harnesses. The 5.3A continuous drain current covers most sub-3A solenoid loads, and the 30V VDS handles 24V inductive kick transients with adequate margin. The rugged 4.5V-25V gate rating tolerates wide gate-drive variations seen in long-cable installations.
推荐
LED Matrix and Backlight Driver Switch
The FDS9435A is suitable for PWM-driven LED matrix rows in small displays, signage, and architectural lighting. The P-channel high-side configuration simplifies per-row enable logic: pulling the gate low turns the row on, pulling it to the supply rail turns the row off. With a 5.3A drain current rating, each row can drive multiple parallel LED strings at typical 20mA-350mA per string. The 30V VDS comfortably handles stacks of 6 to 8 white LEDs (24V to 30V total forward voltage), and the 50 milliohm Rds(on) keeps PWM switching efficiency above 95%.
推荐
推荐产品汇总
工程参考数据： FDS9435A ——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 | FDS9435A-NL | NDS8434A | Si2333DDS | DMG2305UX-7 | AO3401A |
|---|---|---|---|---|---|---|
| Package | 8-SOIC (SO-8) | 8-SOIC (SO-8) - same | 8-SOIC (SO-8) - same | 8-SOIC (SO-8) - same | 8-SOIC (SO-8) - same | 8-SOIC (SO-8) - same |
| Brand | onsemi | onsemi - same brand | onsemi - same brand | Vishay Intertechnology - cross-brand | Diodes Incorporated - cross-brand | Alpha & Omega Semiconductor - cross-brand |
| FET Type / Polarity | P-Channel | P-Channel | P-Channel | P-Channel | P-Channel | P-Channel |
| Drain-to-Source Voltage (VDS) | 30 V | 30 V | 20 V (-33%) | 30 V | 20 V (-33%) | 30 V |
| Continuous Drain Current (ID, Ta) | 5.3 A | 5.3 A | 5.3 A | 6 A (+13%) | 4.6 A (-13%) | 4 A (-25%) |
| Rds(on) at VGS = 10 V | 50 milliohms | 50 milliohms | 50 milliohms | 50 milliohms | 60 milliohms (+20%) | 60 milliohms (+20%) |
| Gate Drive Voltage Range | 4.5 V to 25 V | 4.5 V to 25 V | 4.5 V to 20 V (-20% upper limit) | 4.5 V to 20 V | 1.8 V to 12 V (logic-level) | 4.5 V to 20 V |
| Power Dissipation (PD, Ta) | 2.5 W | 2.5 W | 2.5 W | 2.5 W | 2.0 W (-20%) | 1.4 W (-44%) |
关键差异点
- Rugged 4.5V to 25V gate-drive voltage range （对比 DMG2305UX-7)
- Higher 30V VDS rating than 20V alternatives （对比 NDS8434A)
- Higher continuous drain current than AO3401A （对比 AO3401A)
设计说明
At continuous 5.3A drain current in the SO-8 package, the FDS9435A dissipates approximately 1.4W (I^2 x Rds(on) = 5.3^2 x 50 milliohm). The SO-8 package has a junction-to-ambient thermal resistance of approximately 50 C/W on a standard 1-square-inch copper pour, giving a junction temperature rise of about 70C above ambient. For continuous high-current operation, expand the copper area to at least 2 square inches and add thermal vias under the exposed drain pad (pins 5-8) to keep Tj below 125C.
Use a large copper pour on the Drain pins (5, 6, 7, 8) to maximize heat dissipation. The Source pins (1, 2, 3) should also be connected to a wide copper trace to the source supply. The Gate pin (4) should be routed with a short, narrow trace to the gate-drive signal source, and a 10kohm pull-up or pull-down resistor may be added at the gate to define the default state during controller startup. Minimize the gate loop area to reduce switching noise.
Do not exceed the 30V VDS rating: even brief transients on inductive loads can punch through the device. Add a TVS diode or snubber across the load when switching solenoids, motors, or relays. Also note that the absolute maximum VGS rating is typically +/-20V; the 25V upper drive limit is a recommended operating maximum, not the absolute maximum. Exceeding +/-20V VGS can permanently damage the gate oxide.
Place the FDS9435A close to the load to minimize parasitic inductance in the high-current loop. Use wide, short traces for the Source-to-supply and Drain-to-load paths. Keep the Gate trace away from the Drain switching node to avoid capacitive coupling that could cause false triggering during fast switching transitions. A small gate resistor (10-100 ohm) in series with the gate can slow down switching and reduce ringing.
合规信息
RoHS and REACH compliant per onsemi product page. Not AEC-Q100 qualified - this is a commercial-grade part. Lead-free and halogen-free per onsemi environmental compliance data.
