Diodes Incorporated AP7361EA-18ER-13

Overview

AP7361EA-18ER-13 from Diodes Incorporated is a 1A, fixed-output (1.8V), ultra-low dropout linear regulator with enable function in SOT223R package. It delivers ±1% output voltage accuracy, 360mV dropout at 1A (for 3.3V version; 1.8V dropout is 400mV typ), and 68µA quiescent current-enabling efficient power delivery in space-constrained, battery-powered systems such as LCD monitors and set-top boxes.

For engineers reviewing the AP7361EA-18ER-13 datasheet, AP7361EA-18ER-13 pinout, AP7361EA-18ER-13 application, or AP7361EA-18ER-13 equivalent, key selection criteria include dropout performance at 1.8V output, EN pin logic thresholds (VIH = 1.0V min), thermal shutdown threshold (150°C), and compatibility with 2.2µF MLCC output capacitors.

Technical Context

The AP7361EA-18ER-13 integrates a PMOS pass element, precision 0.8V bandgap reference, error amplifier, and foldback current limiting. Its fixed 1.8V output is internally trimmed, eliminating external resistor networks required in adjustable variants.

Enable control operates with VIH ≥ 1.0V and VIL ≤ 0.3V, supporting direct interfacing with 1.8V/3.3V logic. Thermal shutdown activates at ~150°C with 20°C hysteresis, and short-circuit protection limits output to 400mA during fault conditions.

Key Specifications

Pinout & Package

SOT223R package: thermally enhanced 4-pin variant with exposed pad (EP) connected to GND for improved heat dissipation; footprint matches standard SOT223 but adds dedicated EN pin.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-1802E/MB and XC6210B182MR-G, the AP7361EA-18ER-13 uniquely balances 1A capability, 400mV dropout, EN control, and SOT223R thermal performance-making it optimal for thermally demanding, medium-power 1.8V applications where reliability across temperature extremes is essential.

Availability

AP7361EA-18ER-13 is available at Aetrix Electronics and suitable for LCD TV power management, set-top box core logic supplies, and portable media player audio codec biasing requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for AP7361EA-18ER-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, with manufacturing certified to IATF 16949 and environmental compliance to RoHS 3 and halogen-free standards.

The AP7361EA belongs to Diodes' high-performance LDO family designed for low-noise, low-dropout power regulation in consumer, computing, and industrial equipment where precision voltage stability and thermal robustness are critical.

FAQ

What is the minimum input voltage required for AP7361EA-18ER-13 to maintain regulation at full 1A load?

The device requires VIN ≥ VOUT + VDROPOUT. With VOUT = 1.8V and typical dropout of 400mV at 1A, minimum VIN is 2.2V. This matches the absolute minimum specified input voltage, enabling operation from aged single-cell Li-ion batteries down to 2.2V under load.

Can AP7361EA-18ER-13 be used without connecting the EN pin?

Yes, but only if the regulator must remain permanently enabled. In that case, tie EN directly to IN. Leaving EN floating is not recommended due to potential noise-induced toggling; the internal EN pull-down resistor is 3.0MΩ, insufficient for noise immunity in noisy environments.

Does the SOT223R package require special PCB layout considerations beyond standard SOT223?

Yes. The SOT223R exposes the thermal pad on the bottom surface, which must be soldered to a ≥100mm² copper pour connected to GND via ≥4 thermal vias (0.3mm diameter). Failure to implement this reduces θJA from 110°C/W to >180°C/W, risking thermal shutdown at 1A above +55°C ambient.

How does the foldback current limit protect the AP7361EA-18ER-13 during output short-circuit events?

Under short-circuit, output current drops from 1.5A limit to ~400mA (foldback level), reducing power dissipation to (VIN − 0.7V) × 0.4A. This prevents junction temperature from exceeding 150°C during sustained faults, allowing safe recovery once the short is removed and VOUT rises above 15% of nominal.