Diodes Incorporated AP7353-25FS4-7

Overview

AP7353-25FS4-7 from Diodes Incorporated is a 250mA low-dropout linear regulator with fixed 2.5V output, ±1% accuracy, 90dB PSRR at 1kHz, 10µV_rms output noise (10Hz–100kHz), and 18µA typical quiescent current. It operates from 2.0V to 5.5V input and delivers stable power to noise-sensitive RF and portable analog circuits in space-constrained wearable devices.

For engineers reviewing the AP7353-25FS4-7 datasheet, AP7353-25FS4-7 pinout, AP7353-25FS4-7 application, or AP7353-25FS4-7 equivalent, key selection criteria include dropout voltage at 250mA (75mV typ. @ 2.5V_OUT), enable threshold compatibility (1.2V high/0.4V low), thermal resistance (237°C/W for X2-DFN1010-4), and stability with 1µF ceramic output capacitors.

Technical Context

The AP7353-25FS4-7 integrates a CMOS-based error amplifier, precision voltage reference, current-limit circuit, and active enable control-enabling fast load transient response (<20µs) and robust short-circuit protection (~350mA clamp). Its non-discharge architecture avoids automatic output discharge during shutdown.

Designed for battery-powered systems, it features ultra-low quiescent current (18µA typ.) and standby current (0.1µA max), while maintaining tight line regulation (0.02%/V) and load regulation (0.004%/mA for Type B package) across –40°C to +85°C ambient.

Key Specifications

Pinout & Package

AP7353-25FS4-7 uses the X2-DFN1010-4 (Type B) 1.0mm × 1.0mm, 0.65mm pitch, 4-terminal surface-mount package with exposed thermal pad (EP). The compact footprint reduces PCB area by >50% vs. SOT-23 while enabling efficient thermal dissipation via EP-to-GND copper fill.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1703T-2502E/MB and XC6210B252MR-G, AP7353-25FS4-7 uniquely balances ultra-low noise (10µV_rms), high PSRR (90dB), and enable control in a 1.0mm² DFN-making it optimal for space-constrained, mixed-signal portable designs requiring both precision and flexibility.

Availability

AP7353-25FS4-7 is available at Aetrix Electronics and suitable for smartphone camera modules, Bluetooth LE audio transmitters, and wearable medical sensors requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for AP7353-25FS4-7 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, with design centers across Asia, Europe, and the US, serving consumer, industrial, and automotive markets.

The AP7353 series targets portable and wearable electronics demanding high PSRR, low noise, and minimal board space-designed specifically for RF, imaging, and precision analog subsystems in battery-constrained environments.

FAQ

What is the thermal resistance (θ_JA) of AP7353-25FS4-7, and how does PCB layout affect it?

The X2-DFN1010-4 package has θ_JA = 237°C/W under JEDEC High-K board conditions. Layout significantly impacts thermal performance: connecting the exposed pad (EP) to ≥100mm² of internal/external GND copper reduces θ_JA by up to 40%. Avoid isolated EP connections-use ≥4 thermal vias (0.3mm diameter) to inner GND planes.

Can AP7353-25FS4-7 operate with a 1µF output capacitor, and what type is recommended?

Yes-AP7353-25FS4-7 is stable with 1µF ceramic output capacitors. X7R or X5R dielectrics are required due to their stable capacitance vs. temperature and DC bias. Avoid Y5V/Z5U types, which can lose >80% capacitance at rated voltage and cause instability or overshoot during load transients.

Does AP7353-25FS4-7 include reverse-current protection or output discharge functionality?

No-AP7353-25FS4-7 is the non-discharge variant (no "D" suffix). It lacks an internal discharge FET, so the output remains floating during shutdown. For applications requiring rapid V_OUT decay (e.g., power sequencing), use AP7353D-25FS4-7, which adds a 35Ω discharge path to GND when disabled.

What is the minimum input voltage needed to maintain 2.5V output at 250mA load?

At 250mA, the typical dropout voltage is 75mV (max 168mV per datasheet). Thus, minimum input is 2.5V + 0.075V = 2.575V. To guarantee regulation across temperature and process variation, design for VIN ≥ 2.68V-especially critical in single-cell Li-ion systems near end-of-discharge (2.8V).