Diodes Incorporated AP1117E33G-13

Overview

AP1117E33G-13 from Diodes Incorporated is a fixed-output 3.3V, 1A low-dropout linear regulator in SOT223 package, designed for stable voltage regulation in space-constrained applications requiring ≤1.4V dropout at full load. It delivers well-regulated 3.3V supply for high-speed bus termination, VGA cards, and PC peripherals with input range 4.8–12V and guaranteed thermal shutdown protection.

For engineers reviewing the AP1117E33G-13 datasheet, AP1117E33G-13 pinout, AP1117E33G-13 application, or AP1117E33G-13 equivalent, key selection criteria include dropout voltage at 1A load, output stability with MLCC capacitors, thermal resistance (θJA = 107°C/W), and industrial-grade junction temperature range (–40°C to +125°C).

Technical Context

The AP1117E33G-13 integrates a precision bandgap reference (1.25V ±2.5%), current-limiting circuitry, and thermal shutdown logic into a monolithic IC. Its internal PNP pass transistor enables 1.4V max dropout at 1A while maintaining <33mV load regulation across 0–1A output current.

It operates as a three-terminal fixed-mode regulator: VIN (Pin 3), VOUT (Pin 2), and GND (Pin 1). Stability is ensured with ≥4.7µF ceramic output capacitor (ESR ≤0.5Ω) and supports both tantalum and MLCC dielectrics-X7R recommended, Y5V prohibited.

Key Specifications

Pinout & Package

SOT223 package with exposed thermal tab electrically connected to VOUT (Pin 2); requires minimum 5mm × 5mm copper pad for thermal management per Diodes Inc. AP02001 layout guidelines.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LD1117S33TR and AZ1117C-3.3TRG1, AP1117E33G-13 offers wider temperature qualification and superior MLCC compatibility, but requires careful attention to VOUT-tab grounding and copper-area thermal design to achieve rated 1A performance.

Availability

AP1117E33G-13 is available at Aetrix Electronics and suitable for PC peripheral power, industrial communication modules, and consumer set-top box logic requiring stable component supply with industrial temperature support and RoHS compliance.

Supply support for AP1117E33G-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 power management, signal integrity, and protection solutions for industrial, computing, and consumer markets.

The AP1117 series targets cost-effective, thermally robust linear regulation in space-constrained applications-designed specifically for high-reliability 3.3V/2.5V/1.8V logic supplies where dropout and noise rejection matter more than efficiency.

FAQ

What is the minimum input voltage required for AP1117E33G-13 to regulate at full 1A load?

The device requires VIN ≥ VOUT + 1.4V to maintain regulation at 1A, so minimum input is 4.7V. At 4.8V input, it delivers full 3.3V output with ≤1.4V dropout. Below this threshold, output drops linearly with input; datasheet guarantees regulation only when VIN exceeds VOUT by ≥1.3V at 1A.

Can AP1117E33G-13 be used with 1µF ceramic capacitors instead of the recommended 4.7µF?

No-1µF violates the minimum output capacitance requirement. The device requires ≥4.7µF ceramic (X7R) or solid tantalum capacitor with ESR ≤0.5Ω for stability. Using 1µF risks oscillation, especially under load transients, as confirmed by frequency compensation analysis in the datasheet's stability section.

Is the thermal tab of AP1117E33G-13 electrically isolated or connected to a pin?

The thermal tab is electrically connected to Pin 2 (VOUT), not isolated. This is explicitly stated in the "Pin Assignments" diagram and "Package Outline Dimensions" notes. PCB layout must treat the tab as part of the VOUT net-no solder mask opening or isolation is permitted unless VOUT routing accommodates it.

Does AP1117E33G-13 support reverse-voltage protection or input surge tolerance?

No-AP1117E33G-13 lacks built-in reverse-voltage or surge protection. Absolute maximum rating for VIN is –0.3V; applying reverse polarity will damage the IC. External protection (e.g., series Schottky diode or TVS) is required if input reversal or transients >18V are possible in the system.