Diodes Incorporated AP2281-3FMG-7

Overview

AP2281-3FMG-7 from Diodes Incorporated is a single P-channel MOSFET high-side load switch with 100µs controlled turn-on slew rate, 80mΩ typical R_DS(ON) at 5V, and integrated fast discharge FET (65Ω typical). It operates from 1.5V to 6V input, supports up to 2A continuous load current, and delivers ultra-low 0.01µA quiescent current-ideal for battery-powered portable electronics requiring precise power sequencing and output discharge.

For engineers reviewing the AP2281-3FMG-7 datasheet, AP2281-3FMG-7 pinout, AP2281-3FMG-7 application, or AP2281-3FMG-7 equivalent, key selection criteria include slew-controlled inrush limiting, active-high enable logic compatibility with 1.5–6V systems, thermal performance in U-DFN2018-6 package, and verified discharge capability for safe rail shutdown in multi-rail mobile platforms.

Technical Context

The AP2281-3FMG-7 integrates a P-channel MOSFET with internal gate driver circuitry that enforces a 100µs typical output voltage rise time under 10Ω load, preventing supply rail collapse during hot-plug events. Its enable threshold is adaptive: VIH ranges from 1.4V (1.5–2.7V VIN) to 1.7V (≥5.25V VIN), ensuring robust logic-level compatibility across mixed-voltage domains.

A dedicated discharge FET (R_DISCH = 65–100Ω) activates automatically when EN is low, rapidly discharging output capacitance without external components. Thermal design leverages the U-DFN2018-6's 78°C/W θ_JA and exposed thermal pad (Pin 7), enabling reliable 2A operation up to +85°C ambient when properly grounded.

Key Specifications

Pinout & Package

AP2281-3FMG-7 uses the U-DFN2018-6 (2.0mm × 1.8mm, 0.5mm pitch) package with an exposed thermal pad (Pin 7) requiring connection to PCB ground plane for optimal thermal performance. Pin numbering follows top-view orientation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-side load switch applications.

Compared with TPS22915YZPR and RT9711CGQW, AP2281-3FMG-7 uniquely combines 1.5V operability, 0.01µA IQ, and integrated 65Ω discharge FET-making it optimal for ultra-low-power, multi-rail portable designs requiring guaranteed output discharge without BOM overhead.

Availability

AP2281-3FMG-7 is available at Aetrix Electronics and suitable for smartphone power sequencing, GPS navigator rail control, and notebook subsystem isolation requiring stable component supply, full lifecycle support, and RoHS-compliant sourcing.

Supply support for AP2281-3FMG-7 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-efficiency power management, signal integrity, and protection solutions for consumer, industrial, and computing markets.

The AP2281 product line delivers slew-controlled, low-IQ load switches optimized for portable electronics requiring precise inrush limiting, rail isolation, and autonomous discharge-addressing critical power sequencing challenges in space-constrained, battery-sensitive designs.

FAQ

What is the maximum continuous load current supported by AP2281-3FMG-7?

The AP2281-3FMG-7 supports up to 2A continuous load current at TA ≤ +85°C with proper thermal design. At VIN = 5V and IOUT = 2A, power dissipation is 0.32W (based on 80mΩ R_DS(ON)). With U-DFN2018-6's 78°C/W θ_JA, junction temperature rise is ~25°C above ambient-well within the 125°C TJ(max) limit when PCB thermal pad is fully implemented.

Does AP2281-3FMG-7 require external components for basic operation?

Yes-two mandatory external capacitors: a 1µF ceramic capacitor between IN and GND for input decoupling, and a 0.1µF ceramic capacitor between OUT and GND for output stability. No external resistors or FETs are needed for enable control or discharge, as both functions are fully integrated. The thermal pad (Pin 7) must be soldered to a grounded copper area with ≥3 thermal vias.

How does the discharge FET operate, and what is its impact on system timing?

The discharge FET activates automatically when EN is pulled low, connecting OUT to GND through a 65Ω typical path. For a 100µF load, this discharges output voltage from 5V to <0.8V in ~9ms (τ = R×C ≈ 6.5ms). This eliminates floating outputs and ensures predictable state transitions-critical for USB OTG role switching or memory subsystem power-down where residual charge could cause enumeration failures or data corruption.

Can AP2281-3FMG-7 be used with 1.5V input systems, and how does performance scale at low voltage?

Yes-AP2281-3FMG-7 is fully specified down to 1.5V input. At VIN = 1.5V, R_DS(ON) increases to 210–280mΩ (vs. 80mΩ at 5V), limiting max continuous current to ~1.1A for <100mW dissipation. VIH remains functional at 1.4V minimum, ensuring reliable enable control even at lowest VIN. Quiescent current stays at 0.01µA, preserving battery life in deep-sleep modes.