Diodes Incorporated AP7361E-18FGE-7

Overview

AP7361E-18FGE-7 from Diodes Incorporated is a 1A fixed-output low-dropout linear regulator with 1.8V output, enable control, and power-good monitoring in a U-DFN3030-8 (Type E) package. It delivers ±1% output accuracy, 360mV dropout at 1A (for 3.3V version; 1.8V dropout is 400mV typical), 60µA quiescent current, and integrated thermal shutdown, current limit, and fold-back short-circuit protection. It is designed for stable local regulation in space-constrained battery-powered and portable electronics.

For engineers reviewing the AP7361E-18FGE-7 datasheet, AP7361E-18FGE-7 pinout, AP7361E-18FGE-7 application, or AP7361E-18FGE-7 equivalent, key selection criteria include fixed 1.8V output voltage, ultra-low IQ for standby efficiency, PG open-drain signaling for supply sequencing, dropout performance under 1A load, and compatibility with 2.2µF MLCC output capacitors.

Technical Context

The AP7361E-18FGE-7 implements a PMOS pass transistor architecture enabling ultra-low dropout and fast transient response. Its internal 0.8V bandgap reference and error amplifier regulate output via feedback to the ADJ/NC pin - unused in this fixed 1.8V variant - ensuring tight line and load regulation (±0.2% and ±1.5%, respectively).

It integrates independent protection blocks: thermal shutdown triggers at +150°C with +20°C hysteresis; current limit activates at 1.5A typical; short-circuit fold-back limits fault current to 400mA; and the open-drain PG pin asserts low when VOUT falls below 82% of nominal (1.476V) and releases high-impedance above 92% (1.656V), supporting reliable power sequencing.

Key Specifications

Pinout & Package

AP7361E-18FGE-7 is housed in a thermally enhanced U-DFN3030-8 (Type E) package with exposed thermal pad (pin #4 GND). The 3.0mm × 3.0mm footprint supports high-density PCB layouts and requires soldering the thermal pad to a dedicated ground plane for optimal thermal performance (θJA = 70°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-1802E/MB and TLC7603CDR, AP7361E-18FGE-7 uniquely balances 1A capability, 400mV dropout at 1.8V, integrated PG, and 60µA IQ in a 3×3mm DFN - making it optimal for compact, battery-sensitive designs requiring full fault protection and sequencing support.

Availability

AP7361E-18FGE-7 is available at Aetrix Electronics and suitable for portable audio devices, industrial HMI panels, and smart home sensors requiring stable component supply, consistent parametric performance, and long-term production continuity.

Supply support for AP7361E-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 AP7361E series belongs to Diodes' high-performance LDO portfolio, engineered specifically for space-constrained, battery-powered systems demanding ultra-low dropout, low IQ, and integrated protection features.

FAQ

What is the minimum input voltage required for AP7361E-18FGE-7 to maintain regulation at 1A load?

The minimum input voltage is calculated as VOUT + VDROPOUT = 1.8V + 0.4V = 2.2V. At 1A load and 25°C, the device maintains regulation down to 2.2V input, matching its absolute minimum VIN rating. Below this, output collapses; design margin should include worst-case dropout increase over temperature and process variation.

Can the PG pin be pulled up to a voltage higher than the input supply?

Yes - the PG pin is rated for pull-up voltages up to 6V, which may exceed VIN. This allows direct interfacing with higher-voltage logic domains (e.g., 3.3V or 5V microcontrollers) even when VIN is only 2.2V–3.3V, simplifying level-shifting requirements in multi-rail systems.

Is an external resistor divider required for AP7361E-18FGE-7?

No - the "18" suffix denotes a factory-trimmed fixed 1.8V output. Pin 3 (ADJ/NC) is internally disconnected and must remain unconnected. Adding external resistors would disrupt regulation and is strictly prohibited per datasheet guidance.

How does thermal performance change if the exposed thermal pad is not soldered to PCB ground?

Omitting thermal pad connection increases θJA from 70°C/W to >150°C/W, causing junction temperature to rise ~80°C higher at 1A load. This risks premature thermal shutdown, reduced lifetime, and potential failure - full thermal pad soldering with ≥4 thermal vias is mandatory for rated 1A operation.