Diodes Incorporated AP7343Q-12W5-7

Overview

AP7343Q-12W5-7 from Diodes Incorporated is an automotive-grade 300mA low-dropout linear regulator with fixed 1.2V output, ±1% accuracy, 75dB PSRR at 1kHz, 60µVrms output noise (10Hz–100kHz), and 35µA quiescent current. It features enable control, thermal shutdown, and short-circuit protection, and is qualified for ADAS camera and infotainment power rails in AEC-Q100 Grade 1 environments.

For engineers reviewing the AP7343Q-12W5-7 datasheet, AP7343Q-12W5-7 pinout, AP7343Q-12W5-7 application, or AP7343Q-12W5-7 equivalent, this page delivers verified package mapping (SOT25), validated pin functions, automotive thermal performance (−40°C to +125°C), and real-world LDO selection criteria including dropout voltage (0.46V typ. @300mA), load transient response, and PCB layout guidance for noise-sensitive RF supplies.

Technical Context

The AP7343Q-12W5-7 uses a CMOS-based architecture with integrated voltage reference, error amplifier, and current-limit circuitry. Its enable input provides precise on/off control with defined logic thresholds (EN high ≥1.3V, EN low ≤0.5V), and it lacks internal discharge functionality-confirmed by part suffix "W5" and ordering table distinction from AP7343DQ variants.

It operates across 1.7V–5.25V input range while maintaining 1.2V output stability under 300mA load, with dropout voltage specified at 0.46V (typ) and 0.72V (max) at full load. Thermal protection activates at +150°C with +20°C hysteresis, and the device achieves 75dB ripple rejection at 1kHz due to high PSRR design optimized for automotive RF and sensor supply domains.

Key Specifications

Pinout & Package

AP7343Q-12W5-7 is packaged in SOT25 (5-pin, 2.9mm × 2.8mm × 1.3mm), a thermally enhanced surface-mount package with exposed pad not present - distinct from W-DFN2020-6 variants. Pin 4 is NC (no connect), recommended tied to GND for thermal relief; pin 5 is VOUT; pin 1 is VIN; pin 2 is EN; pin 3 is GND.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AP7343Q-12W5-7, the FDZW variant improves thermal management in dense layouts but demands PCB redesign, while TLD1121-12ESV50 trades noise/PSRR for wide-input flexibility-neither is pin-compatible, and both require validation of load transient response and startup timing in target systems.

Availability

AP7343Q-12W5-7 is available at Aetrix Electronics and suitable for automotive infotainment power supplies, ADAS camera modules, and RF subsystems requiring stable component supply with AEC-Q100 compliance and traceable sourcing.

Supply support for AP7343Q-12W5-7 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 manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability power management, signal integrity, and protection solutions for automotive, industrial, and computing markets.

The AP7343Q belongs to Diodes' automotive-qualified LDO portfolio, designed specifically for noise-sensitive point-of-load regulation in ADAS, infotainment, and telematics systems where PSRR, low noise, and AEC-Q100 Grade 1 operation are mandatory.

FAQ

Is AP7343Q-12W5-7 pin-compatible with AP7343DQ-12W5-7?

No. AP7343Q-12W5-7 lacks internal output discharge, while AP7343DQ-12W5-7 integrates an active discharge FET. Though both share identical pinout and electrical specs under normal operation, the DQ version pulls VOUT to GND within 100µs after EN deactivation-critical for systems requiring rapid rail collapse. Swapping them without verifying discharge timing may cause reset glitches or data corruption in downstream logic.

What is the minimum input voltage required for stable 1.2V output at 300mA?

The minimum input voltage is 1.66V, calculated from the typical dropout voltage of 0.46V added to the nominal 1.2V output. At maximum load and worst-case conditions (−40°C, aging), the guaranteed dropout is 0.72V, so 1.92V input ensures regulation across full temperature and lifetime. Input below 1.7V violates Recommended Operating Conditions and risks output collapse.

Can AP7343Q-12W5-7 be used without an output capacitor?

No. The datasheet mandates ≥1µF ceramic output capacitance for stability and transient response. Omitting COUT causes oscillation under load steps, evidenced by ringing in load transient waveforms (Fig. 8–9). Ceramic capacitors with X5R/X7R dielectric and ≤10mΩ ESR are required; tantalum or aluminum electrolytics alone are insufficient due to higher ESR and instability risk.

Does AP7343Q-12W5-7 require a heatsink in SOT25 package at 300mA continuous load?

No external heatsink is needed, but PCB thermal design is critical. With θJA = 179°C/W, 300mA at 1.2V output (0.36W dissipation) yields ~64°C junction rise above ambient. At +85°C ambient, TJ ≈ 149°C - near thermal shutdown. Use ≥2oz copper, thermal vias under pin 3 (GND), and connect pin 4 (NC) to GND pour to reduce θJA by up to 30°C and ensure margin below +150°C.