Diodes Incorporated AP7361EA-33E-13

Overview

AP7361EA-33E-13 from Diodes Incorporated is a 1A fixed-output (3.3V), ultra-low dropout linear regulator in SOT223 package with enable input, ±1% output accuracy, 360mV dropout at 1A, and 68µA quiescent current-designed for stable power delivery in battery-powered audio/video equipment and LCD monitors.

For engineers reviewing the AP7361EA-33E-13 datasheet, AP7361EA-33E-13 pinout, AP7361EA-33E-13 application, or AP7361EA-33E-13 equivalent, key selection criteria include dropout voltage at full load, EN logic thresholds, thermal resistance (θJA = 110°C/W), and compatibility with 2.2µF MLCC output capacitors without minimum load requirement.

Technical Context

The AP7361EA-33E-13 integrates a PMOS pass element, band-gap reference, error amplifier, and thermal shutdown circuitry. Its fixed 3.3V output is internally trimmed, eliminating external feedback resistors while maintaining ±1% accuracy over -40°C to +85°C ambient temperature.

Enable functionality operates with VIH ≥ 1.0V and VIL ≤ 0.3V, supporting direct GPIO control. Foldback short-circuit protection limits output current to 400mA during fault conditions, and current limiting activates at 1.5A nominal to prevent damage under overload.

Key Specifications

Pinout & Package

SOT223 package (Type E) with exposed thermal pad; requires PCB copper area connected to GND for optimal thermal performance (θJA = 110°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700-3302E/TO and TLS850F3TLE, the AP7361EA-33E-13 uniquely balances 1A output capability, 360mV dropout, and 68µA IQ in a cost-effective SOT223 package-making it optimal for mid-power consumer electronics where both current capacity and efficiency matter.

Availability

AP7361EA-33E-13 is available at Aetrix Electronics and suitable for LCD monitor power rails, set-top box AV core supplies, and smart home appliance MCU cores requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for AP7361EA-33E-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 AP7361EA belongs to Diodes' high-performance LDO regulator product line, engineered for low-dropout, low-noise, and enable-controlled power delivery in space-constrained consumer and industrial electronics.

FAQ

What is the minimum input voltage required for stable 3.3V output at 1A?

The AP7361EA-33E-13 requires VIN ≥ VOUT + VDROPOUT = 3.3V + 0.36V = 3.66V for full 1A output. At lower inputs, output current derates per the dropout curve-e.g., at 3.5V input, maximum load is ~850mA. Input must remain ≥2.2V for basic functionality, but regulation fails below dropout margin.

Can the EN pin be left floating, or must it be tied high/low?

The EN pin must never be left floating-it has no internal pull-up/down. For always-on operation, tie EN directly to IN. For controlled enable, drive with a clean logic signal meeting VIH ≥ 1.0V and VIL ≤ 0.3V. Floating EN causes unpredictable startup behavior and potential output instability due to noise coupling.

Is an output capacitor mandatory, and what type is recommended?

Yes, a minimum 2.2µF ceramic capacitor is mandatory on the OUT pin for stability and transient response. MLCCs are preferred due to low ESR; tantalum or polymer capacitors may be used if ESR is 10–100mΩ. No minimum ESR is required, and no minimum load is needed-the device remains stable down to zero load.

How does thermal shutdown behave during sustained overload?

At junction temperature ≥150°C, thermal shutdown disables the output. Once junction cools to ~130°C (20°C hysteresis), regulation resumes automatically. Under continuous overload, this causes on/off cycling-limiting average power dissipation but potentially disrupting downstream circuitry. Proper PCB copper area and airflow are essential to avoid cycling in 1A applications.