Diodes Incorporated AP7361EA-18FGE-7

Overview

AP7361EA-18FGE-7 from Diodes Incorporated is a 1A ultra-low dropout linear regulator with fixed 1.8V output, enable control, and U-DFN3030-8 (Type E) package. It delivers ±1% output accuracy, 360mV dropout at 1A (for 3.3V), and 68µA typical quiescent current. Designed for battery-powered devices and audio/video equipment, it integrates thermal shutdown, foldback short-circuit protection (400mA), and current limiting (1.5A).

For engineers reviewing the AP7361EA-18FGE-7 datasheet, AP7361EA-18FGE-7 pinout, AP7361EA-18FGE-7 application, or AP7361EA-18FGE-7 equivalent, key selection criteria include dropout voltage at 1A load, EN logic thresholds (VIH = 1.0V, VIL = 0.3V), stability with ≥2.2µF MLCC output capacitance, and thermal resistance (θJA = 70°C/W) in the U-DFN3030-8 package.

Technical Context

The AP7361EA-18FGE-7 uses a PMOS pass transistor architecture enabling ultra-low dropout operation and high PSRR (75dB @ 1kHz). Its internal 0.8V bandgap reference and error amplifier support precise output regulation across input voltages from 2.2V to 6.0V.

Enable functionality is implemented via a dedicated EN pin with 3.0MΩ internal pull-down resistor and ±0.1µA leakage; activation requires VIH ≥ 1.0V. Protection circuitry includes foldback current limiting (triggers at ~1.1A, clamps short-circuit current to 400mA) and thermal shutdown at +150°C with 20°C hysteresis.

Key Specifications

Pinout & Package

AP7361EA-18FGE-7 is housed in a thermally enhanced U-DFN3030-8 (Type E) package with exposed pad (EP) for improved heat dissipation. The 3.0mm × 3.0mm footprint supports high-density layouts and requires connection of the EP to GND via multiple thermal vias for optimal θJA = 70°C/W performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1703T-1802E/MB and TLS850B2ELVSE, AP7361EA-18FGE-7 uniquely balances 1A output, ultra-low dropout (250mV typ. @ 1.8V), and industrial-temp operation (-40°C to +85°C) in a 3×3mm DFN - making it optimal for space-constrained, medium-power consumer electronics where automotive certification is unnecessary.

Availability

AP7361EA-18FGE-7 is available at Aetrix Electronics and suitable for portable audio devices, LCD monitor power rails, IoT sensor nodes, and set-top box SoC core supply requiring stable component supply, consistent parametric performance, and long-term production continuity.

Supply support for AP7361EA-18FGE-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 semiconductor manufacturer 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-noise, low-dropout operation in battery-powered and noise-sensitive systems - emphasizing efficiency, thermal robustness, and ease of integration.

FAQ

What is the minimum input voltage required for AP7361EA-18FGE-7 to regulate 1.8V at 1A?

The minimum input voltage is determined by dropout: 250mV typical at 1A for 1.8V output. Thus, VIN(min) = 1.8V + 0.25V = 2.05V. However, the absolute minimum specified input is 2.2V per datasheet - ensuring guaranteed regulation across process, voltage, and temperature corners. Operating below 2.2V risks loss of regulation or increased dropout.

Can AP7361EA-18FGE-7 be used without connecting the exposed pad (EP)?

No. The EP is thermally critical: θJA degrades from 70°C/W to >120°C/W if unconnected, causing premature thermal shutdown at ≤500mA load. Diodes specifies mandatory soldering of EP to a GND-connected copper area with ≥4 thermal vias (0.3mm diameter). Leaving EP floating violates thermal design requirements and voids performance guarantees.

Does AP7361EA-18FGE-7 require an external resistor divider for 1.8V output?

No. AP7361EA-18FGE-7 is the fixed 1.8V variant; the ADJ/NC pin is not functional and must remain unconnected. Only adjustable versions (e.g., AP7361EA-FGE-7) use the ADJ pin with R1/R2 to set output voltage. Connecting resistors to ADJ/NC on this part will disrupt internal feedback and cause regulation failure.

How does the foldback short-circuit protection behave during a sustained output short?

When OUT shorts to GND, the regulator immediately limits current to ~400mA (not 1.5A current limit). This foldback action reduces power dissipation (P = 1.8V × 0.4A = 0.72W), preventing thermal runaway. Output recovers automatically once short is removed and VOUT rises above 0.27V (15% of 1.8V); no manual reset is needed.