Diodes Incorporated AP7361C-33SPR-13

Overview

AP7361C-33SPR-13 from Diodes Incorporated is a 1A fixed-output (3.3V), ultra-low dropout linear regulator with enable, designed for point-of-load regulation in space-constrained power rails. It delivers ±1% output accuracy, 360mV dropout at 1A, and 60µA quiescent current, supporting stable operation in battery-powered audio/video systems and LCD-TVs.

For engineers reviewing the AP7361C-33SPR-13 datasheet, AP7361C-33SPR-13 pinout, AP7361C-33SPR-13 application, or AP7361C-33SPR-13 equivalent, key selection criteria include dropout voltage at full load, thermal shutdown threshold (150°C), EN logic thresholds (VIH ≥ 1.0V), PSRR (75dB @ 1kHz), and SO-8EPR package thermal resistance (θJA = 100°C/W).

Technical Context

The AP7361C-33SPR-13 integrates a PMOS pass element, band-gap reference (0.8V), error amplifier, and fold-back current limiting (400mA short-circuit clamp). Its fixed 3.3V output eliminates external resistor divider requirements while retaining EN-controlled sequencing capability.

It operates across 2.2V–6.0V input range with line regulation of 0.1%/V and load regulation of ±1.0% over 1.2V–3.3V outputs. Thermal shutdown activates at 150°C with 20°C hysteresis, enabling safe cycling under sustained overload conditions.

Key Specifications

Pinout & Package

AP7361C-33SPR-13 uses the SO-8EPR package: thermally enhanced 8-pin exposed-pad surface-mount package with pin 1 (IN), pin 2 (GND), pin 3 (OUT), pin 4 (GND), pin 5 (EN), pin 6 (NC), pin 7 (NC), pin 8 (GND). The exposed thermal pad must be soldered to PCB ground plane for θJA = 100°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 MCP1700-3302E/TO and TLS850B2LF33, AP7361C-33SPR-13 uniquely balances 1A output, EN control, and SO-8EPR thermal performance-making it optimal for consumer electronics requiring both high current and compact thermal management.

Availability

AP7361C-33SPR-13 is available at Aetrix Electronics and suitable for LCD-TV power management, set-top box core logic supply, and smart home appliance MCU supply requiring stable component supply, consistent parametric performance, and long-term production continuity.

Supply support for AP7361C-33SPR-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 IATF16949:2016 and environmental compliance to RoHS 3 and halogen-free standards.

The AP7361C belongs to Diodes' high-performance LDO portfolio targeting portable and consumer electronics, emphasizing ultra-low dropout, low IQ, and multi-package flexibility for design-in scalability.

FAQ

What is the minimum input voltage required for AP7361C-33SPR-13 to maintain regulation at 1A load?

The minimum input voltage is calculated as VOUT + VDROPOUT = 3.3V + 0.36V = 3.66V. At 1A load and 25°C, the device maintains regulation down to this input level. Below 3.66V, output voltage drops proportionally per the dropout characteristic curve in the datasheet.

Can AP7361C-33SPR-13 operate without an output capacitor?

No. A minimum 2.2µF ceramic capacitor is mandatory between OUT and GND for stability. Omitting it causes oscillation and potential damage. The capacitor must be placed within 2mm of the OUT and GND pins, with low-ESR construction recommended.

Is the EN pin internally pulled down, and what happens if left unconnected?

Yes-the EN pin has a 3.0MΩ internal pull-down resistor. If left unconnected, the device remains disabled. To ensure reliable turn-on, drive EN to ≥1.0V using a GPIO or connect directly to IN for always-on operation.

How does thermal performance differ between SO-8EPR and U-DFN3030-8 packages at 1A load?

SO-8EPR has θJA = 100°C/W versus U-DFN3030-8's 70°C/W. At 1A with 3.66V input, power dissipation is (3.66−3.3)×1 = 0.36W. SO-8EPR junction rise is 36°C above ambient; U-DFN3030-8 rises only 25°C-enabling higher ambient operation or smaller heatsinking.