Diodes Incorporated AP7315D-26FS4-7B

Overview

AP7315D-26FS4-7B from Diodes Incorporated is a 2.6V fixed-output, 150mA low-dropout linear regulator with high PSRR (75dB at 1kHz), ultra-low output noise (60µVrms, 10Hz–100kHz), ±1% output voltage accuracy, and enable-controlled shutdown. It employs CMOS process technology and integrates current limiting, thermal protection, and auto-discharge functionality. Designed for RF supply rails in compact portable electronics, it operates from 1.7V to 5.25V input and delivers stable bias under fast load transients.

For engineers reviewing the AP7315D-26FS4-7B datasheet, AP7315D-26FS4-7B pinout, AP7315D-26FS4-7B application, or AP7315D-26FS4-7B equivalent, key selection criteria include dropout voltage at 150mA (max 0.29V), quiescent current (35µA typ), EN logic thresholds (0.5V low / 1.3V high), thermal performance in X2-DFN1010-4, and discharge capability for rapid VOUT decay during shutdown.

Technical Context

The AP7315D-26FS4-7B implements a CMOS-based LDO architecture with integrated voltage reference, error amplifier, and N-channel pass transistor. Its built-in auto-discharge path (30Ω typical ON-resistance) actively pulls VOUT to GND when EN is low, eliminating residual charge in downstream capacitance.

It supports wide-input operation (1.7V–5.25V) while maintaining ±1% output accuracy across –40°C to +85°C and exhibits robust line/load regulation (0.1%/V and 1.0%/A max). The device achieves 75dB ripple rejection at 1kHz and sustains stability with only 0.47µF ceramic input/output capacitors.

Key Specifications

Pinout & Package

X2-DFN1010-4 package: 1.0mm × 1.0mm, 0.4mm pitch, thermally enhanced with exposed pad (not electrically connected to GND by default; recommended to tie to GND plane for thermal relief).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700-2602E/TO and XC6206P262MR-G, the AP7315D-26FS4-7B uniquely combines 2.6V precision regulation, 150mA delivery, ultra-low noise, and integrated discharge in a 1.0mm² DFN-making it optimal for space-constrained, noise-sensitive, and rapidly cycled portable RF systems.

Availability

AP7315D-26FS4-7B is available at Aetrix Electronics and suitable for RF power amplifier bias, camera sensor core supply, wireless adapter baseband regulation, and portable media player audio codec applications requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for AP7315D-26FS4-7B 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 consumer, industrial, and automotive markets.

The AP7315 series belongs to Diodes' high-PSRR, low-noise LDO product line, engineered specifically for noise-critical portable electronics where compact size, rapid transient response, and clean power delivery are essential.

FAQ

What is the function of the thermal pad on the X2-DFN1010-4 package?

The thermal pad on the AP7315D-26FS4-7B's X2-DFN1010-4 package is a non-electrical thermal interface designed to enhance heat dissipation. It must be soldered to a large PCB copper area connected to GND for optimal thermal performance. While it improves power handling up to 400mW, it is not an electrical GND terminal and should not be used as the sole ground connection.

Does AP7315D-26FS4-7B require an external discharge resistor?

No. The "D" suffix denotes integrated auto-discharge functionality. When EN is pulled low, an internal 30Ω NMOS switch connects VOUT to GND, actively discharging output capacitance. This eliminates the need for external bleed resistors, saving board space and reducing BOM count in portable designs.

Can AP7315D-26FS4-7B operate with a 1.8V input supply?

Yes. With a 2.6V output and maximum dropout of 0.29V at 150mA, the AP7315D-26FS4-7B requires minimum VIN = 2.89V. A 1.8V input is below the operational range and will cause dropout failure. Valid input range is strictly 1.7V–5.25V, but usable VIN must exceed VOUT + dropout (≥2.89V for full 150mA).

How does the AP7315D-26FS4-7B handle short-circuit conditions?

Under VOUT-to-GND short, the AP7315D-26FS4-7B activates fold-back current limiting, clamping output current to approximately 55–60mA. This protects the device from thermal damage while maintaining safe junction temperature. Recovery is automatic upon fault removal, with no latch-off or manual reset required.