Diodes Incorporated AP7340D-25FS4-7

Overview

AP7340D-25FS4-7 from Diodes Incorporated is a 2.5V fixed-output, 150mA low-dropout linear regulator with ±1% output voltage accuracy, 75dB PSRR at 1kHz, and 60µV_RMS output noise (10Hz–100kHz). It features enable control, ultra-low 35µA quiescent current, and operates from 1.7V to 5.25V input. Designed for RF supply rails in portable wireless devices, it delivers stable biasing under fast load transients.

For engineers reviewing the AP7340D-25FS4-7 datasheet, AP7340D-25FS4-7 pinout, AP7340D-25FS4-7 application, or AP7340D-25FS4-7 equivalent, key selection criteria include dropout voltage at 150mA (0.21–0.27V), EN logic thresholds (0.5V low / 1.3V high), thermal performance in X2-DFN1010-4, and built-in auto-discharge functionality.

Technical Context

The AP7340D-25FS4-7 integrates a CMOS-based error amplifier, precision voltage reference, current-limit circuit, and active pull-down transistor for output discharge during shutdown. Its architecture enables fast line/load transient response while maintaining stability with 0.47µF ceramic capacitors on both input and output.

This variant includes an internal discharge path (R_ON ≈ 30Ω) activated when EN = low, ensuring rapid VOUT decay to prevent back-powering downstream circuitry. The device operates across –40°C to +85°C ambient and supports up to 300mA short-circuit foldback current.

Key Specifications

Pinout & Package

AP7340D-25FS4-7 uses the X2-DFN1010-4 package (1.0mm × 1.0mm, 0.4mm height), featuring a thermal pad optimized for PCB copper area connection to GND for enhanced power dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-2502E/TT and XC6210B252MR-G, the AP7340D-25FS4-7 uniquely balances RF-grade PSRR (75dB), integrated discharge, and 150mA capability in a 1.0mm² footprint-making it optimal for space-constrained, noise-sensitive wireless subsystems.

Availability

AP7340D-25FS4-7 is available at Aetrix Electronics and suitable for smartphone RF supply, portable camera sensor bias, and BLE SoC I/O regulation requiring stable component supply, traceable sourcing, and lifecycle continuity.

Supply support for AP7340D-25FS4-7 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 semiconductor company specializing in discrete, analog, and mixed-signal solutions for power management, signal integrity, and connectivity applications.

The AP7340 series belongs to Diodes' high-PSRR, low-noise LDO portfolio, engineered specifically for noise-sensitive RF, imaging, and portable communication subsystems demanding precision regulation in minimal footprint.

FAQ

What is the purpose of the thermal pad on the AP7340D-25FS4-7 package?

The thermal pad is a non-electrical mechanical feature designed to enhance heat transfer from the die to the PCB. It must be soldered to a ≥25mm² copper area connected to GND (or left floating) to improve thermal resistance by up to 40°C/W. It is not a functional ground terminal and must not be used as the sole GND connection.

Does AP7340D-25FS4-7 require external capacitors, and what values are recommended?

Yes - a 0.47µF ceramic capacitor is required between VIN and GND, and another 0.47µF ceramic capacitor between VOUT and GND. Both must be placed within 1mm of their respective pins. Larger bulk capacitors (e.g., 10µF tantalum) may be added in parallel for high-dV/dt loads, but the 0.47µF ceramics are mandatory for stability.

How does the auto-discharge function operate, and when is it active?

The auto-discharge path (≈30Ω) connects VOUT to GND only when EN is driven low. It activates within 1µs of EN falling below 0.5V and discharges a 1µF load from 2.5V to 0.1V in <100µs. This prevents back-powering of upstream circuitry during power sequencing or fault conditions.

Can AP7340D-25FS4-7 be used with input voltages below 1.7V?

No - the absolute minimum input voltage is 1.7V per datasheet specifications. Operation below this threshold risks improper regulation, increased dropout, or failure to maintain 2.5V output. For sub-1.7V applications, consider alternative LDOs with ultra-low VIN capability, such as the AP2204K-25.