Diodes Incorporated AP7361C-28DR-13

Overview

AP7361C-28DR-13 from Diodes Incorporated is a 1A fixed-output (2.8V) ultra-low dropout linear regulator with enable, designed for power rail regulation in space-constrained portable electronics. It delivers ±1% output accuracy, 360mV dropout at 1A (for 3.3V variant; 2.8V dropout is 340mV typ), 60µA quiescent current, and integrates thermal shutdown, fold-back short-circuit protection (400mA), and current limiting (1.5A). It is used in LCD-TV power rails where stable low-noise 2.8V supply is required for display logic.

For engineers reviewing the AP7361C-28DR-13 datasheet, AP7361C-28DR-13 pinout, AP7361C-28DR-13 application, or AP7361C-28DR-13 equivalent, key selection considerations include dropout voltage at 2.8V output, EN pin logic thresholds (VIH = 1.0V min), thermal resistance of TO252-R package (95°C/W), stability with ≥2.2µF MLCC output capacitors, and compatibility with no-load operation.

Technical Context

The AP7361C-28DR-13 implements a PMOS pass transistor architecture enabling ultra-low dropout and high PSRR (75dB @ 1kHz). Its internal 0.8V bandgap reference and error amplifier regulate output via feedback to the ADJ/NC pin - unused in fixed 2.8V configuration, where internal resistor divider sets VOUT.

Enable control is implemented as active-high logic on the EN pin, with VIH ≥ 1.0V and VIL ≤ 0.3V; EN is not available in SOT223/TO252 standard variants but is supported in TO252-R (DR) package. Protection functions include fold-back current limiting (400mA short-circuit clamp), thermal shutdown at 150°C with 20°C hysteresis, and internal current limit at 1.5A.

Key Specifications

Pinout & Package

AP7361C-28DR-13 is packaged in TO252-R (DPAK-R), a 3-pin variant with reversed pinout: Pin 1 = GND, Pin 2 = OUT, Pin 3 = IN. The exposed thermal pad is electrically connected to GND and must be soldered to a thermal copper plane for effective heat dissipation (θJA = 95°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1703T-2802E/MB and XC6210B282MR-G, AP7361C-28DR-13 uniquely combines 1A capability, TO252-R thermal robustness (95°C/W), and integrated EN functionality - making it optimal for thermally demanding, medium-power 2.8V applications requiring controlled power sequencing.

Availability

AP7361C-28DR-13 is available at Aetrix Electronics and suitable for LCD-TV power rails, set-top box USB regulators, smart home hub peripherals, and home appliance MCU supplies requiring stable component supply across industrial temperature ranges and long production lifecycles.

Supply support for AP7361C-28DR-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 manufacturer specializing in discrete, analog, and mixed-signal solutions for power management, signal integrity, and connectivity applications.

The AP7361C belongs to Diodes' high-performance LDO family targeting portable and consumer electronics, engineered for ultra-low dropout, low IQ, and robust protection in compact packages like TO252-R and U-DFN3030-8.

FAQ

What is the minimum input voltage required for AP7361C-28DR-13 to maintain regulation at full 1A load?

The minimum input voltage is calculated as VOUT + VDROPOUT = 2.8V + 0.34V = 3.14V. At 1A load and 25°C, the device maintains regulation down to 3.14V input; below this, output voltage drops nonlinearly. Input must remain ≥2.2V per absolute rating, but regulation is only guaranteed above 3.14V under full load.

Can AP7361C-28DR-13 operate without an output capacitor?

No. The datasheet explicitly requires ≥2.2µF ceramic output capacitance for stability. Omitting COUT causes oscillation and potential damage due to phase margin loss. The device is optimized for MLCCs but also stable with solid polymer or low-ESR electrolytic capacitors meeting the 2.2µF minimum.

Is the EN pin internally pulled up or down in AP7361C-28DR-13?

The EN pin has no internal pull-up or pull-down. It exhibits 3.0MΩ internal pull-down resistance (RENPD), meaning it will default to OFF if left floating. For always-on operation, EN must be tied directly to IN; for controlled enable, drive with a logic signal meeting VIH ≥ 1.0V and VIL ≤ 0.3V.

How does thermal performance differ between TO252 (D) and TO252-R (DR) packages for AP7361C-28DR-13?

TO252-R (DR) has identical mechanical dimensions but reversed pinout (GND/OUT/IN) and optimized thermal pad layout. Its θJA is 95°C/W versus 95°C/W for standard TO252 (D) - identical when mounted per recommended footprint. However, DR's pin 1 = GND simplifies grounding the thermal pad, improving real-world thermal reliability in high-density layouts.