Diodes Incorporated AP1117E25L-13

Overview

AP1117E25L-13 from Diodes Incorporated is a 1A low-dropout linear regulator in fixed 2.5V output mode, housed in a thermally enhanced SOT223 package. It delivers stable regulation with ≤1.4V dropout at full load, supports 6.4–18V input range, and features built-in thermal shutdown and current limiting - deployed in PC peripherals, VGA cards, and 3.3V/2.5V logic supply rails.

For engineers reviewing the AP1117E25L-13 datasheet, AP1117E25L-13 pinout, AP1117E25L-13 application, or AP1117E25L-13 equivalent, key selection criteria include dropout voltage at 1A load, thermal resistance (θJA = 107°C/W on standard FR-4), output capacitor ESR limits (≤0.5Ω), junction temperature range (0°C to +125°C), and SOT223 thermal tab connection to VOUT.

Technical Context

The AP1117E25L-13 implements a bandgap-referenced error amplifier driving a PNP pass transistor, enabling fixed 2.5V output without external resistors. Its internal current limit (~1.1A) and thermal shutdown activate at ~150°C junction temperature, providing fault protection during overload or poor heatsinking.

Designed for low-noise, low-ESR ceramic capacitor compatibility, it achieves 70dB ripple rejection at 180Hz and maintains ±1% load regulation across 0–1A output current. The device requires ≥4.7µF input/output capacitors with ESR between 0.15Ω and 0.5Ω for guaranteed stability.

Key Specifications

Pinout & Package

AP1117E25L-13 uses the SOT223 surface-mount package with exposed thermal tab electrically connected to VOUT. The tab must be soldered to a ≥5mm×5mm 2oz copper pour for thermal performance. Pin 1 (Adj/GND) is internally tied to ground for fixed-output variants; Pin 2 (VOUT) supplies regulated 2.5V; Pin 3 (VIN) accepts 4–18V input.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AP1117E25L-13, AP1117E25G-13 adds halogen-free certification without trade-offs, while LD1117S25TR offers lower dropout and better thermal performance but increases idle power draw - choice depends on priority between environmental compliance, efficiency, or thermal headroom.

Availability

AP1117E25L-13 is available at Aetrix Electronics and suitable for PC peripheral design, VGA card manufacturing, and consumer audio equipment requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for AP1117E25L-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 semiconductor company specializing in discrete, analog, and mixed-signal solutions for power management, signal integrity, and connectivity applications.

The AP1117 series belongs to Diodes' precision linear regulator product line, engineered for cost-sensitive, high-volume applications demanding reliability, low dropout, and robust thermal protection in commercial and industrial environments.

FAQ

What is the minimum input voltage required for AP1117E25L-13 to maintain regulation?

The AP1117E25L-13 requires VIN ≥ VOUT + dropout voltage. With a maximum dropout of 1.4V at 1A, the minimum valid input is 3.9V. At lighter loads (<100mA), dropout drops to ~1.2V, allowing operation down to ~3.7V - but design margin should retain 4.0V minimum for full-load reliability.

Can AP1117E25L-13 be used with ceramic capacitors, and what ESR range is acceptable?

Yes - AP1117E25L-13 is explicitly characterized for stability with X7R MLCCs ≥4.7µF. The datasheet specifies an ESR range of 0.15Ω to 0.5Ω; values outside this window risk oscillation. Y5V dielectrics are prohibited due to capacitance drift with voltage/temperature.

Is the thermal tab of the SOT223 package electrically connected, and how must it be handled?

Yes - the thermal tab is internally bonded to Pin 2 (VOUT). It must be soldered to a dedicated copper pour tied to the 2.5V output net, not system ground. This connection provides both thermal conduction and electrical continuity; floating or grounding the tab causes regulation failure and thermal runaway.

Does AP1117E25L-13 require an external bypass capacitor on the ADJ pin?

No - AP1117E25L-13 is the fixed 2.5V variant; Pin 1 (Adj/GND) is internally shorted to ground. No external components are needed on this pin. Adding resistors or capacitors here would disrupt internal feedback and cause output voltage error or instability.