Diodes Incorporated AP1117EL-13

Overview

AP1117EL-13 from Diodes Incorporated is a 1A low-dropout linear regulator in fixed 3.3V output mode, housed in a SOT223 package. It delivers stable voltage regulation with ≤1.4V dropout at full load, supports 6.4–18V input, and operates across 0°C to +125°C junction temperature. Designed for high-speed bus termination and low-current 3.3V logic supply, it enables compact power delivery in PC peripherals and VGA cards.

For engineers reviewing the AP1117EL-13 datasheet, AP1117EL-13 pinout, AP1117EL-13 application, or AP1117EL-13 equivalent, key selection criteria include dropout voltage at 1A load, thermal shutdown behavior, output capacitor ESR requirements (≤0.5Ω), and fixed 3.3V output tolerance (±2% at 10mA).

Technical Context

The AP1117EL-13 integrates a precision bandgap reference (1.25V ±2.5%), current-limiting circuitry, and thermal shutdown protection triggered at ~150°C. Its internal pass transistor uses a PNP-based architecture optimized for low dropout and fast transient response under dynamic load changes.

It requires external 4.7µF ceramic or tantalum output capacitance (ESR 0.15–0.5Ω) for stability and supports MLCCs-unlike legacy 1117 variants-enabling smaller, more reliable decoupling in space-constrained designs.

Key Specifications

Pinout & Package

SOT223 package with exposed thermal tab connected to VOUT for enhanced heat dissipation. Pin 1 (Adj/GND) serves as ground for fixed-output variants; Pin 2 (VOUT) supplies regulated 3.3V; Pin 3 (VIN) accepts 4.7–18V input. The metal tab is electrically tied to Pin 2 and must be soldered to a thermal pad.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AP1117E33-13, AP1117EL-13 offers identical performance but distinct traceability; versus LD1117S33TR, it provides superior noise immunity and ceramic capacitor compatibility-critical for high-speed digital loads.

Availability

AP1117EL-13 is available at Aetrix Electronics and suitable for PC peripheral design, VGA card manufacturing, and consumer equipment logic rail applications requiring stable component supply, consistent thermal performance, and RoHS-compliant packaging.

Supply support for AP1117EL-13 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 AP1117 series targets cost-sensitive, space-constrained applications needing robust fixed- or adjustable-output LDOs with enhanced thermal and transient performance over legacy 1117 architectures.

FAQ

What is the minimum input voltage required for AP1117EL-13 to regulate 3.3V output at 1A?

The AP1117EL-13 requires VIN ≥ VOUT + dropout voltage. With max dropout of 1.4V at 1A, minimum input is 4.7V. Datasheet specifies 4.8V minimum for test conditions, and operation below this risks loss of regulation during load transients or temperature rise.

Can AP1117EL-13 be used with 10µF X5R ceramic capacitors on input and output?

Yes-AP1117EL-13 is explicitly qualified for MLCCs including X5R and X7R dielectrics. Input and output require ≥4.7µF with ESR between 0.15Ω and 0.5Ω; 10µF X5R meets both criteria and improves transient response over tantalum alternatives.

Does AP1117EL-13 include reverse-polarity or reverse-current protection?

No. AP1117EL-13 lacks internal reverse-voltage or reverse-current blocking. If input can fall below output (e.g., during power-down), an external Schottky diode from VIN to VOUT is required to prevent backfeed and potential damage to upstream circuitry.

How does thermal shutdown behave during sustained overload?

When junction temperature reaches ~150°C, the AP1117EL-13 disables its pass transistor and holds output at 0V until die cools to ~135°C, then resumes regulation. This hiccup-mode cycling prevents permanent damage but causes intermittent output-designers must size heatsinking to avoid repeated triggering.