Diodes Incorporated AP7341D-33FS4-7

Overview

AP7341D-33FS4-7 from Diodes Incorporated is a 300mA, 3.3V fixed-output low-dropout linear regulator with ±1% output voltage accuracy, 75dB PSRR at 1kHz, and 60µV_rms output noise (10Hz–100kHz), designed for RF supply rails in portable wireless communication devices using a CMOS process and integrated enable control.

For engineers reviewing the AP7341D-33FS4-7 datasheet, AP7341D-33FS4-7 pinout, AP7341D-33FS4-7 application, or AP7341D-33FS4-7 equivalent, key selection criteria include dropout voltage at 300mA (≤0.40V), quiescent current (35µA typ), EN logic thresholds (0.5V_IL/1.3V_IH), and thermal performance in the X2-DFN1010-4 package.

Technical Context

The AP7341D-33FS4-7 implements a CMOS-based LDO architecture with internal voltage reference, error amplifier, current-limit circuit, and active discharge function enabled by the 'D' suffix. It operates across 1.7V–5.25V input range while maintaining regulation under load transients up to 300mA.

Its enable pin (EN) provides precise on/off control with 1µA standby current and supports direct tie-to-VIN for always-on operation. The device includes fold-back short-circuit protection (55mA typical) and thermal shutdown, with output stability guaranteed using ≥1.0µF ceramic capacitors.

Key Specifications

Pinout & Package

AP7341D-33FS4-7 uses the X2-DFN1010-4 (1.0mm × 1.0mm, 0.4mm pitch) package with exposed thermal pad. PCB layout requires large copper area connected to GND under the thermal pad for optimal thermal dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-3302E/TT and XC6206P332MR-G, the AP7341D-33FS4-7 uniquely combines 300mA drive, ±1% accuracy, EN control, active discharge, and 60µV_rms noise in a 1.0mm² DFN - making it optimal for RF and imaging subsystems demanding both precision and dynamic control.

Availability

AP7341D-33FS4-7 is available at Aetrix Electronics and suitable for smartphone RF supply, portable camera modules, wireless communication adapters, and portable media player audio codecs requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for AP7341D-33FS4-7 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 manufacturer of discrete semiconductors and analog ICs, specializing in high-performance power management, signal integrity, and protection solutions for consumer, industrial, and communications markets.

The AP7341 series belongs to Diodes' high-PSRR, low-noise LDO product line, engineered specifically for noise-sensitive RF, imaging, and portable multimedia applications where power integrity directly impacts signal fidelity.

FAQ

What is the minimum input voltage required for AP7341D-33FS4-7 to maintain regulation at 300mA?

The minimum input voltage is determined by dropout: at 300mA and 3.3V output, max dropout is 0.40V, so VIN must be ≥3.70V. However, per Recommended Operating Conditions, the absolute minimum VIN is 1.7V - but regulation is only guaranteed above VOUT + dropout voltage. For full 300mA capability at 3.3V, VIN ≥3.7V is required.

Does AP7341D-33FS4-7 require an external pull-up resistor on the EN pin?

No external pull-up is required. The EN pin has no internal pull-up; however, it must not be left floating. If enable control is unused, Diodes recommends tying EN directly to VIN to ensure reliable turn-on. A pull-up to VIN satisfies the >1.3V threshold and avoids undefined states.

How does the 'D' suffix affect the functionality of AP7341D-33FS4-7 compared to non-D variants?

The 'D' suffix denotes integrated active discharge: when EN is pulled low, an internal N-channel MOSFET connects VOUT to GND, rapidly discharging output capacitance. Non-D versions (e.g., AP7341-33FS4-7) lack this feature, leaving VOUT floating after shutdown - which can cause latch-up or sequencing issues in multi-rail systems.

Can AP7341D-33FS4-7 operate with a 0.47µF output capacitor?

Yes - the datasheet specifies stability with ≥0.47µF ceramic capacitors. However, for optimal transient response under 300mA load steps, Diodes recommends ≥1.0µF. Capacitor ESR must remain below 100mΩ (per ESR vs. IOUT graph on p.10); X5R/X7R 0.47µF ceramics typically meet this if rated for ≥6.3V.