Diodes Incorporated AP7311-15WG-7

Overview

AP7311-15WG-7 from Diodes Incorporated is a 150mA fixed-output (1.5V) low-dropout linear regulator in SOT25 package, featuring 65µA quiescent current, 150mV dropout at full load, and 65dB PSRR at 100Hz. It integrates enable control, thermal shutdown, current limiting, and short-circuit protection - designed for battery-powered portable devices requiring stable, ultra-low-power voltage regulation.

For engineers reviewing the AP7311-15WG-7 datasheet, AP7311-15WG-7 pinout, AP7311-15WG-7 application, or AP7311-15WG-7 equivalent, key selection criteria include fixed 1.5V output accuracy (±2%), fast 80µs startup, stability with 1µF ceramic output capacitor, and operation across –40°C to +85°C ambient.

Technical Context

The AP7311-15WG-7 implements a PMOS pass transistor architecture with internal 0.4V reference and error amplifier, enabling low dropout and minimal IQ across 2V–6V input range. Its EN pin provides logic-level (VIH = 1.4V) on/off control, while built-in protection circuits independently trigger at ~300mA current limit, ~50mA short-circuit clamp, and 140°C thermal shutdown with 15°C hysteresis.

Designed for transient-sensitive loads, it delivers excellent line/load regulation (±0.2%/V and ±0.6%) and fast transient response without external compensation. The device remains stable with no minimum load and supports ultra-low-noise operation via 1µF input/output ceramic capacitors - eliminating need for tantalum or high-ESR alternatives.

Key Specifications

Pinout & Package

SOT25 (5-pin, 2.9mm × 1.6mm × 1.1mm) surface-mount package with RoHS-compliant lead-free finish and green molding compound (no Br/Sb). Thermal resistance θ_JA = 190°C/W on standard FR-4 PCB with recommended pad layout.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar fixed-output LDO regulator applications.

Compared with MCP1700T-1502E/TT and TPS70615DRVR, the AP7311-15WG-7 offers optimal balance of ultra-low dropout (150mV), moderate IQ (65µA), and robust protection - making it ideal for mid-discharge-phase portable applications where both battery voltage headroom and standby efficiency matter.

Availability

AP7311-15WG-7 is available at Aetrix Electronics and suitable for wireless sensor nodes, portable medical monitors, and industrial I/O modules requiring stable component supply, RoHS compliance, and SOT25 footprint compatibility.

Supply support for AP7311-15WG-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-reliability power management, signal integrity, and protection solutions for industrial, computing, and consumer markets.

The AP7311 belongs to Diodes' low-quiescent-current LDO family, engineered specifically for battery-constrained portable electronics needing fast transient response, minimal dropout, and integrated fault protection without external components.

FAQ

What is the minimum input voltage required for AP7311-15WG-7 to maintain 1.5V output at 150mA?

The AP7311-15WG-7 requires a minimum input voltage of 1.65V to sustain 1.5V output at 150mA, based on its typical 150mV dropout voltage. At lower inputs, output regulation degrades - e.g., at VIN = 1.6V, VOUT drops to ~1.45V. Input must remain ≥2V per absolute maximum rating to avoid damage.

Can AP7311-15WG-7 operate without an output capacitor?

No - the AP7311-15WG-7 requires a minimum 1µF ceramic output capacitor connected between OUT and GND for stability and transient response. Omitting it causes oscillation and unregulated output. The datasheet confirms stability only with 1–4.7µF X5R/X7R ceramics (ESR 10–200mΩ); no-load operation is supported, but capacitor is mandatory.

Is the EN pin internally pulled up or does it require external biasing?

The EN pin has no internal pull-up or pull-down; it is a high-impedance CMOS input requiring explicit logic-level drive. To ensure reliable turn-on, connect EN directly to VIN (for always-on) or to a clean digital signal with VIH ≥1.4V and VIL ≤0.4V. Leaving EN floating may cause unpredictable enable/disable behavior due to noise coupling.

How does thermal shutdown behave under sustained overload conditions?

Under sustained overload, the AP7311-15WG-7 triggers thermal shutdown at ~140°C junction temperature, disabling the output. Once junction cools to ~125°C (15°C hysteresis), regulation resumes automatically. This cycling limits average power dissipation and prevents permanent damage - but repeated cycling indicates inadequate PCB copper area or excessive ambient temperature (>85°C).