Diodes Incorporated AP7347D-12FDZW-7B

Overview

AP7347D-12FDZW-7B from Diodes Incorporated is a 1.2V fixed-output, 500mA low-dropout linear regulator with ±1% output voltage accuracy, 75dB PSRR at 1kHz, and 60µV_rms output noise (10Hz–100kHz). It features enable control, thermal shutdown, short-circuit protection, and auto-discharge functionality. Designed for noise-sensitive automotive and portable electronics, it operates from 1.7V to 5.5V input and delivers stable 1.2V power to core logic rails in compact PCB layouts.

For engineers reviewing the AP7347D-12FDZW-7B datasheet, AP7347D-12FDZW-7B pinout, AP7347D-12FDZW-7B application, or AP7347D-12FDZW-7B equivalent, key selection criteria include dropout voltage at 500mA (0.65V typ.), quiescent current (60µA typ.), EN logic thresholds (0.5V_IL/1.25V_IH), and W-DFN2020-6 thermal resistance (θ_JA = 54°C/W).

Technical Context

The AP7347D-12FDZW-7B integrates a CMOS-based LDO architecture with internal voltage reference, error amplifier, current-limit circuit, and NMOS pass transistor with auto-discharge path. Its enable input directly controls the pass device gate via internal logic, supporting fast turn-on/turn-off response (≤200µs) without external components.

It achieves high PSRR through multi-stage error amplifier compensation and low-noise biasing, while maintaining stability with 1µF ceramic input/output capacitors. The W-DFN2020-6 package includes an exposed thermal pad optimized for PCB copper area connection to GND, enabling junction-to-ambient thermal resistance of 54°C/W under JEDEC STD-51 conditions.

Key Specifications

Pinout & Package

AP7347D-12FDZW-7B uses the W-DFN2020-6 (SWP) Type A1 wettable flanks package (2.0mm × 2.0mm × 0.75mm), featuring an exposed thermal pad (EP) for enhanced thermal dissipation. PCB layout requires large copper area connected to GND under EP, with recommended solder mask opening per Diodes' suggested pad layout (C=0.65mm, X1=1.4mm, Y=0.8mm).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 1.2V, 500mA LDO applications.

Compared with AP7347D-12FDZW-7B, AP7361D-12FDZW-7B offers higher current headroom at the expense of noise and IQ, while XC6210B122MR-G reduces cost and noise but sacrifices thermal capability and integrated discharge-making AP7347D-12FDZW-7B optimal for thermally constrained, noise-sensitive automotive and industrial applications requiring robust power sequencing.

Availability

AP7347D-12FDZW-7B is available at Aetrix Electronics and suitable for automotive body control modules, industrial PLC I/O cards, medical wearable sensor hubs, and 5G small cell baseband processors requiring stable component supply across extended temperature ranges and high reliability.

Supply support for AP7347D-12FDZW-7B 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-performance power management, signal integrity, and protection solutions for automotive, industrial, and computing markets.

The AP7347D series belongs to Diodes' high-PSRR, low-noise LDO product line, designed specifically for noise-sensitive applications in automotive ADAS, infotainment, and body electronics where clean, accurate, and sequenced power delivery is critical.

FAQ

What is the minimum input voltage required for AP7347D-12FDZW-7B to regulate 1.2V at 500mA?

The minimum input voltage is determined by dropout: at 500mA, typical dropout is 0.65V, so VIN must be ≥1.85V. Per datasheet, guaranteed operation starts at VIN = 1.7V-but regulation at full 500mA is only assured above 1.85V. Below that, output voltage sags proportionally to (VIN – VOUT) until dropout threshold is reached.

Does AP7347D-12FDZW-7B require an external discharge resistor?

No. The device integrates an NMOS auto-discharge path (30Ω typical) between VOUT and GND, activated automatically when EN is pulled low. This eliminates the need for external resistors or FETs, reducing BOM count and PCB area while ensuring rapid VOUT decay (<100µs) for safe power-down sequencing.

Can AP7347D-12FDZW-7B be used in automotive applications?

Yes-the AP7347DQ variant is AEC-Q100 qualified, but the standard AP7347D-12FDZW-7B shares identical electrical specs, thermal performance, and construction. It operates from -40°C to +125°C ambient, includes thermal shutdown and short-circuit protection, and is widely deployed in non-safety-critical automotive modules such as infotainment power rails and body control peripherals.

What is the recommended PCB layout for the exposed pad (EP) on W-DFN2020-6?

Per Diodes' package outline, the EP must be connected to a large GND copper pour using ≥4 thermal vias (0.3mm diameter, spaced ≤1mm apart) to an internal GND plane. Do not use EP as the sole GND return for high-current paths. Solder mask should be opened fully over EP, and stencil aperture should match pad size (1.4mm × 0.6mm) to ensure void-free solder joint formation.