Diodes Incorporated AP7343-25FS4-7B

Overview

AP7343-25FS4-7B from Diodes Incorporated is a 300mA, 2.5V fixed-output low-dropout linear regulator with ±1% output accuracy, 75dB PSRR at 1kHz, and 60µV_rms output noise (10Hz–100kHz). Built on a CMOS process, it features enable control, thermal shutdown, and short-circuit protection-designed for RF supply rails in compact portable electronics.

For engineers reviewing the AP7343-25FS4-7B datasheet, AP7343-25FS4-7B pinout, AP7343-25FS4-7B application, or AP7343-25FS4-7B equivalent, key selection criteria include its 0.25V typical dropout at 300mA (V_OUT = 2.5V), 35µA quiescent current, X2-DFN1010-4 (Type B) package footprint, and EN-controlled power sequencing capability.

Technical Context

The AP7343-25FS4-7B integrates a precision voltage reference, error amplifier, current-limit circuit, and CMOS pass transistor-enabling stable regulation across 1.7V to 5.25V input while maintaining tight load/line regulation (≤30mV load shift, ≤0.1%/V line shift). Its architecture supports fast transient response with minimal external components: only 1µF input and output ceramic capacitors required.

Thermal management relies on the exposed pad (EP) of the X2-DFN1010-4 (Type B) package, delivering 85.7°C/W junction-to-board thermal resistance. The device enters shutdown when EN < 0.5V and activates fully when EN > 1.3V, with <1.0µA EN leakage and no floating-pin tolerance.

Key Specifications

Pinout & Package

The AP7343-25FS4-7B is housed in the X2-DFN1010-4 (Type B) package-a 1.0mm × 1.0mm, 0.4mm pitch, 4-terminal leadless package with an exposed thermal pad (EP). The EP must be connected to a large copper area tied to GND for optimal thermal performance (R_θJB = 85.7°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700-2502E/TO and XC6210B252MR-G, the AP7343-25FS4-7B uniquely balances 300mA drive, ±1% accuracy, and 1.0mm² footprint-making it optimal for space-constrained RF and imaging subsystems requiring both precision and density.

Availability

AP7343-25FS4-7B is available at Aetrix Electronics and suitable for RF power amplifier biasing, camera ISP power delivery, wireless adapter modules, and portable media player audio codec supplies requiring stable component supply across high-mix consumer electronics production.

Supply support for AP7343-25FS4-7B 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 company specializing in discrete, analog, and mixed-signal solutions for power management, signal integrity, and connectivity applications.

The AP7343 series targets portable and battery-powered systems-designed to deliver high PSRR, low noise, and minimal quiescent current in sub-1mm² packages for smartphones, tablets, and wearables.

FAQ

What is the maximum allowable input voltage for AP7343-25FS4-7B?

The absolute maximum input voltage is 6.0V, but the recommended operating range is 1.7V to 5.25V. Exceeding 5.25V risks violating safe operating area limits, especially under high ambient temperature or heavy load-potentially triggering thermal shutdown or degrading long-term reliability.

Does AP7343-25FS4-7B include output discharge functionality?

No-the "7B" suffix and absence of "D" in the part number indicate the non-discharge variant. When disabled via EN, the output remains floating and does not actively pull VOUT to GND. For automatic discharge, select AP7343D-25FS4-7B, which adds an internal NMOS discharge path (R_ON ≈ 30Ω).

Can AP7343-25FS4-7B operate with only a 0.47µF input capacitor?

Yes-Diodes specifies a minimum 0.47µF ceramic capacitor between VIN and GND for stability and input decoupling. However, for applications with large load transients (e.g., burst-mode RF transmission), a 1µF capacitor is recommended to prevent input droop and ensure robust line regulation.

How does the exposed pad (EP) on the X2-DFN1010-4 package affect thermal performance?

The EP significantly lowers thermal resistance: R_θJB is 85.7°C/W when soldered to a 25mm² GND copper area, versus >200°C/W without it. It must be soldered-not used as an electrical GND connection-and thermally coupled to the PCB's inner ground plane for effective heat spreading.