Diodes Incorporated AP7347D-25FDZW-7B

Overview

AP7347D-25FDZW-7B from Diodes Incorporated is a 2.5V fixed-output, 500mA low-dropout linear regulator with ±1% output voltage accuracy, 75dB PSRR at 1kHz, 60µV_rms output noise (10Hz–100kHz), and 60µA quiescent current. It features enable control, thermal shutdown, short-circuit protection, and auto-discharge functionality, housed in a wettable W-DFN2020-6 (SWP) package for automotive-grade PCB reliability.

For engineers reviewing the AP7347D-25FDZW-7B datasheet, AP7347D-25FDZW-7B pinout, AP7347D-25FDZW-7B application, or AP7347D-25FDZW-7B equivalent, key selection criteria include dropout voltage at 500mA (0.31–0.36V for 2.5V output), EN logic thresholds (0.5V_IL/1.25V_IH), thermal resistance (θ_JA = 54°C/W), and compatibility with 1µF ceramic input/output capacitors.

Technical Context

The AP7347D-25FDZW-7B implements a CMOS-based LDO architecture with integrated voltage reference, error amplifier, current-limit circuit, and NMOS pass transistor with auto-discharge path. Its enable input controls regulator state via TTL/CMOS-compatible logic levels, while internal thermal shutdown triggers at +170°C with +20°C hysteresis.

Designed for noise-sensitive systems, it achieves high PSRR through optimized internal compensation and low-noise biasing, maintaining stability with minimal 1µF ceramic capacitors on both input and output. The W-DFN2020-6 (SWP) package supports enhanced thermal dissipation via exposed pad connection to PCB ground plane.

Key Specifications

Pinout & Package

AP7347D-25FDZW-7B is packaged in a 2.0mm × 2.0mm, 0.75mm height W-DFN2020-6 (SWP) (Type A1) wettable flanks package with exposed thermal pad (EP). This RoHS-compliant, halogen-free "Green" package supports automated optical inspection (AOI) and improves solder joint reliability in automotive and industrial applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AP7347D-25FDZW-7B, the AP7361D variant offers higher current headroom at the expense of slightly reduced efficiency, while the MCP1826 trades PSRR, accuracy, and package reliability for lower unit cost in consumer-grade applications.

Availability

AP7347D-25FDZW-7B is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor nodes, medical wearables, and point-of-sale terminals requiring stable component supply, high-reliability packaging, and long-term lifecycle support.

Supply support for AP7347D-25FDZW-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 semiconductor manufacturer specializing in discrete, analog, and mixed-signal solutions for automotive, industrial, computing, and consumer markets.

The AP7347D series targets noise-sensitive, space-constrained applications requiring high PSRR, low IQ, and automotive-compliant packaging - particularly in ADAS subsystems, battery-powered sensors, and portable medical devices.

FAQ

What is the minimum input voltage required for AP7347D-25FDZW-7B to regulate 2.5V at 500mA?

The minimum input voltage is determined by dropout: 2.5V + 0.36V = 2.86V. Per datasheet specifications, the device maintains regulation down to VIN = 2.86V at full load and TJ = +125°C. At room temperature and light load, it can operate as low as 1.7V but will not sustain 500mA below the dropout threshold.

Can the NC pins (2 and 5) be left floating in the W-DFN2020-6 package?

No - pins 2 and 5 are internally unconnected but thermally and electrically coupled to the die substrate. Diodes recommends connecting them to GND to improve thermal conduction and reduce EMI susceptibility. Floating these pins may degrade thermal performance and increase radiated emissions in sensitive layouts.

Does AP7347D-25FDZW-7B require an external discharge resistor for safe shutdown?

No - the device integrates an auto-discharge NMOS (R_ON ≈ 30Ω) between VOUT and GND when EN is low. This eliminates the need for external components to bleed off output capacitance, simplifying BOM and ensuring predictable power-down timing in sequenced systems.

Is the exposed pad (EP) electrically connected to GND inside the AP7347D-25FDZW-7B package?

No - the exposed pad is a thermal slug only, not bonded to any internal die node. It must be connected to PCB GND copper for heat dissipation but must not serve as the sole GND return path. Internal GND is routed exclusively through pin 3; EP provides thermal conduction only.