Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

Home > Products > Discrete Semiconductor Products > Transistors > FETs, MOSFETs > FETs, MOSFETs

Alpha & Omega Semiconductor Inc. AO4438

Name: AO4438
Brand: Alpha & Omega Semiconductor Inc.
SKU: AO4438
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: AO4438

Manufacturer:: Alpha & Omega Semiconductor Inc.

Category:: FETs, MOSFETs

Package:: 8-SOIC (0.154", 3.90mm Width)

Datasheet:: AO4438.pdf

Description:: MOSFET N-CH 60V 8.2A 8SOIC

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:9,675

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

AO4438 from Alpha & Omega Semiconductor is a 60V N-channel MOSFET in SOIC-8 package, featuring R_DS(ON) < 22 mΩ at V_GS = 10 V and 8.2 A continuous drain current. It employs advanced trench technology for low gate charge and high UIS robustness, and is used as a load switch or PWM power stage in DC-DC converters.

For engineers reviewing the AO4438 datasheet, pinout, applications, or equivalent options, key selection criteria include its 60 V V_DS, 22 mΩ on-resistance at 10 V drive, SOIC-8 thermal performance (R_θJA = 40 °C/W), body-diode reverse recovery time of 34–41 ns, and 100% UIS-tested reliability for industrial switching.

Technical Context

The AO4438 is a single N-channel enhancement-mode MOSFET with trench-gate structure optimized for low conduction and switching losses. Its gate threshold voltage (2.0–3.0 V) enables compatibility with 3.3 V and 5 V logic-level drivers, and its 0.65–0.8 Ω gate resistance supports controlled turn-on/turn-off timing.

Thermal design relies on its SOIC-8 package with R_θJL = 21 °C/W (junction-to-lead) and R_θJA = 40 °C/W (steady-state, 1 in² FR-4, 2 oz Cu). The device's 1920–2300 pF input capacitance and 116 pF reverse transfer capacitance define its high-frequency gate drive requirements in PWM applications.

Key Specifications

Parameter	Value and Actual Design Meaning
V_DS	60 V - Maximum blocking voltage for mid-voltage DC-DC and motor control stages
I_D (continuous)	8.2 A at T_A = 25 °C - Sustains full-load current in compact SOIC-8 without forced cooling
R_DS(ON)	< 22 mΩ at V_GS = 10 V - Minimizes conduction loss in 12–48 V systems
Q_g(10 V)	47.6–58 nC - Determines gate driver power and switching speed in 100–500 kHz PWM
t_r/t_f	5.5 ns / 5.2 ns - Enables fast edge rates for reduced switching loss and EMI
Body diode t_rr	34–41 ns - Supports synchronous rectification and limits reverse recovery loss
R_θJA	40 °C/W - Defines thermal derating curve on standard PCB layout

Pinout & Package

SOIC-8 surface-mount package with exposed drain pad (internally connected to pins 1, 2, 3, 4, 5, 6, 7, and 8 are not all drains - see pin table below). Thermal performance assumes soldered drain pad to copper pour.

Pin/Terminal	Circuit Role	Design Meaning
1, 2, 3, 4, 5, 6, 7, 8	Drain (D)	Pins 1–4 and 6–8 are internally tied to drain; pin 5 is gate; pins 7–8 also connect to source - per top/bottom view labeling and internal die layout
5	Gate (G)	Single gate input; requires 10 V for full enhancement; compatible with 3.3 V logic when operated in linear region
7, 8	Source (S)	Source terminals; dual-source configuration improves current sharing and reduces source inductance in high-di/dt switching

Key Features

Feature	Design Value
100% UIS tested	Guarantees ruggedness under unclamped inductive switching stress up to rated I_DM and V_DS
Low Q_g/Q_gd ratio	Q_gd/Q_g ≈ 24–25% - Improves Miller immunity and reduces risk of false turn-on in half-bridge configurations
Enhanced body diode	t_rr = 34–41 ns and Q_rr = 53 nC - Reduces reverse recovery loss versus standard MOSFETs in freewheeling paths
100% R_g tested	Ensures consistent gate resistance (0.65–0.8 Ω) for predictable switching timing and driver sizing

Applications

DC-DC Buck Converter	Hot-Swap Controller
Use Scenario: High-efficiency 12 V to 3.3 V/5 V step-down conversion in telecom and server power supplies. IC Role / Device Role / Timing Role: Synchronous high-side or low-side power switch operating at 300–500 kHz. Use Value: 22 mΩ R_DS(ON) minimizes conduction loss; fast 5.5 ns rise time enables high-frequency operation with low switching loss.	Use Scenario: Inrush current limiting and fault isolation in 24–48 V backplane systems. IC Role / Device Role / Timing Role: Load switch controlled by external gate driver or analog controller. Use Value: 60 V V_DS headroom accommodates line transients; 100% UIS rating ensures survival during hot-plug surge events.
Motor Driver Half-Bridge	LED Constant-Current Driver
Use Scenario: Low-voltage brushed DC motor control in industrial actuators and HVAC fans. IC Role / Device Role / Timing Role: Low-side switch in PWM-driven H-bridge with body-diode freewheeling. Use Value: 34–41 ns t_rr and 53 nC Q_rr reduce shoot-through risk and power dissipation during commutation.	Use Scenario: Dimmable LED string driver in architectural and signage lighting. IC Role / Device Role / Timing Role: PWM-controlled current sink for constant-current regulation. Use Value: 8.2 A I_D supports multi-string parallel operation; SOIC-8 footprint simplifies thermal management on LED driver PCBs.

DC-DC Buck Converter

Hot-Swap Controller

Use Scenario: High-efficiency 12 V to 3.3 V/5 V step-down conversion in telecom and server power supplies.

IC Role / Device Role / Timing Role: Synchronous high-side or low-side power switch operating at 300–500 kHz.

Use Value: 22 mΩ R_DS(ON) minimizes conduction loss; fast 5.5 ns rise time enables high-frequency operation with low switching loss.

Use Scenario: Inrush current limiting and fault isolation in 24–48 V backplane systems.

IC Role / Device Role / Timing Role: Load switch controlled by external gate driver or analog controller.

Use Value: 60 V V_DS headroom accommodates line transients; 100% UIS rating ensures survival during hot-plug surge events.

Motor Driver Half-Bridge

LED Constant-Current Driver

Use Scenario: Low-voltage brushed DC motor control in industrial actuators and HVAC fans.

IC Role / Device Role / Timing Role: Low-side switch in PWM-driven H-bridge with body-diode freewheeling.

Use Value: 34–41 ns t_rr and 53 nC Q_rr reduce shoot-through risk and power dissipation during commutation.

Use Scenario: Dimmable LED string driver in architectural and signage lighting.

IC Role / Device Role / Timing Role: PWM-controlled current sink for constant-current regulation.

Use Value: 8.2 A I_D supports multi-string parallel operation; SOIC-8 footprint simplifies thermal management on LED driver PCBs.

Equivalent & Alternatives

The following parts are listed as comparable options for similar N-channel MOSFET applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
IRF7470PBF	R_DS(ON) = 21 mΩ @ 10 V, but higher Q_g (62 nC) and slower t_r (12 ns)	Less suitable for >300 kHz switching due to higher gate charge and slower edges	Prefer AO4438 where high-frequency efficiency and fast switching are critical
Si2308DS-T1-E3	Lower voltage rating (30 V), smaller SOT-23 package, R_DS(ON) = 28 mΩ @ 4.5 V	Limited to ≤24 V systems; unsuitable for 48 V bus or inductive load protection	Choose AO4438 for 60 V capability, SOIC-8 thermal margin, and 100% UIS qualification

Compared with IRF7470PBF and Si2308DS-T1-E3, the AO4438 delivers superior high-frequency switching performance via lower Q_g and faster t_r/t_f, while maintaining 60 V robustness and SOIC-8 thermal handling - making it optimal for compact, high-efficiency 12–48 V power stages requiring reliability under transient stress.

Availability

AO4438 is available at Aetrix Electronics and suitable for DC-DC converters, hot-swap controllers, motor driver half-bridges, and LED constant-current drivers requiring stable component supply and long-term industrial availability.

Supply support for AO4438 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

Alpha & Omega Semiconductor (AOS) is a fabless power semiconductor company specializing in high-performance MOSFETs, IGBTs, and power ICs for computing, consumer, and industrial markets.

The AO4438 belongs to AOS's TrenchMOS™ family, engineered for high-efficiency, high-reliability switching in mid-voltage power conversion and load management applications.

FAQ

What is the maximum continuous drain current rating for the AO4438?

The AO4438 has a maximum continuous drain current (I_D) of 8.2 A at T_A = 25 °C, derating to 6.6 A at T_A = 70 °C. This rating assumes SOIC-8 mounting on 1 in² FR-4 board with 2 oz copper and still air. Actual current capability depends on PCB layout, ambient temperature, and heatsinking. The AO4438 must be operated within its Safe Operating Area (SOA) curve, especially under pulsed conditions.

Is the AO4438 suitable for 3.3 V logic-level gate drive?

The AO4438 has a gate threshold voltage (V_GS(th)) of 2.0–3.0 V, enabling partial turn-on with 3.3 V drive, but its R_DS(ON) is specified at 27 mΩ only at V_GS = 4.5 V and 22 mΩ at V_GS = 10 V. For full enhancement and minimal conduction loss, 10 V gate drive is recommended. The AO4438 is not classified as a true logic-level MOSFET for 3.3 V-only operation.

Does the AO4438 have an integrated Schottky body diode?

No, the AO4438 uses a standard parasitic body diode formed by its vertical N-channel MOSFET structure. Its body diode has V_SD = 0.74–1.0 V at I_S = 1 A and reverse recovery time t_rr = 34–41 ns. It is not a Schottky or merged PIN-Schottky device; however, its trench process yields improved reverse recovery characteristics over planar MOSFETs.

What does "100% UIS tested" mean for the AO4438?

"100% UIS tested" means every AO4438 unit undergoes unclamped inductive switching stress testing at rated I_DM and V_DS to verify ruggedness against inductive energy spikes - common in motor drives and relay loads. This qualification ensures the AO4438 survives worst-case turn-off events without failure, distinguishing it from non-UIS-rated MOSFETs that may degrade or fail under similar conditions.

Can the AO4438 be used in parallel configurations?

Yes, the AO4438 supports paralleling due to its positive temperature coefficient of R_DS(ON), which promotes current sharing as junction temperature rises. However, matched gate drive routing, symmetrical PCB layout, and individual gate resistors are required to ensure balanced switching. The dual-source pin configuration (pins 7 and 8) helps reduce source inductance imbalance in parallel setups. Always verify thermal coupling and current distribution in final design.

AO4438 Specifications

Product attributes: Attribute value

Manufacturer:: Alpha & Omega Semiconductor Inc.

Series:: -

Package/Case:: 8-SOIC (0.154", 3.90mm Width)

Packaging:: Tape & Reel (TR)

Product Status:: Obsolete

FET Type:: N-Channel

Technology:: MOSFET (Metal Oxide)

Drain to Source Voltage (Vdss):: 60 V

Current - Continuous Drain (Id) @ 25°C:: 8.2A (Ta)

Drive Voltage (Max Rds On, Min Rds On):: 4.5V, 10V

Rds On (Max) @ Id, Vgs:: 22mOhm @ 8.2A, 10V

Vgs(th) (Max) @ Id:: 3V @ 250µA

Gate Charge (Qg) (Max) @ Vgs:: 58 nC @ 10 V

Vgs (Max):: ±20V

Input Capacitance (Ciss) (Max) @ Vds:: 2300 pF @ 30 V

FET Feature:: -

Power Dissipation (Max):: 3.1W (Ta)

Operating Temperature:: -55°C ~ 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: 8-SOIC

AO4438 FAQ

1.How can I place an order for AO4438 through Aetrix?

Please submit a Request for Quotation (RFQ) for AO4438 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 AO4438 reliable?

The price and inventory of AO4438 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AO4438 is usually 5 days.

3.What payment methods are accepted for AO4438?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AO4438 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for AO4438?

AO4438 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your AO4438 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 AO4438?

For technical support, including AO4438 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AO4438 requirements.

6.How does Aetrix verify that AO4438 is sourced from the original manufacturer or authorized distributors?

All AO4438 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 AO4438 meets industry standards.

7.What is the process for return or replacement of AO4438?

All AO4438 units undergo pre-shipment inspection (PSI). If there is an issue with AO4438, 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 AO4438 part is unused and in its original packaging.

Return procedure for AO4438:

1.Submit a request within 90 days.

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

Tech Hub

2026-09-11 Comparator Circuit: Voltage Thresholds, Op-Amp Differences, LM393 and Practical Design

Comparator circuit design covering voltage thresholds, input limits, open-collector outputs, LM393 wiring, op-amp differences, hysteresis, timing, window detection and practical fault diagnosis.

2026-09-10 Schmitt Trigger Explained: Hysteresis, Circuits, Inverters and Applications

Schmitt triggers use separate rising and falling thresholds to stabilize slow or noisy signals. This guide covers hysteresis, 74HC14 and 74HCT14 selection, comparator calculations, RC oscillators and p…

2026-09-09 Counterfeit Electronic Components: How to Detect, Authenticate, and Test Suspect Parts

Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …

2026-09-08 Obsolete Electronic Components: How to Source and Evaluate Replacements

A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.

2026-09-07 TTL vs CMOS Logic Levels: 74HC and 74HCT Compatibility Explained

TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.

2026-09-04 Logic Level Shifter: How to Connect 3.3V and 5V Logic Safely

A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.

2026-09-03 74HC595 vs TPIC6B595: Output Drive, Pinout, Current, and Load Selection

The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…

2026-09-02 74HC595 Pinout, Timing, Output Current, and Applications

The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…

2026-09-01 Latch vs Flip-Flop: Timing, Differences and Design Choices

A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…

2026-08-30 D Latch Circuit: Truth Table, Timing, ICs and Applications

A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …