Diodes Incorporated AP7343D-295FS4-7B

Overview

AP7343D-295FS4-7B from Diodes Incorporated is a 300mA low-dropout linear regulator with fixed 2.95V output, high PSRR (75dB at 1kHz), ultra-low noise (60µV_rms, 10Hz–100kHz), ±1% output voltage accuracy, and enable-controlled shutdown. It operates from 1.7V to 5.25V input and delivers stable power to RF circuitry, camera modules, and portable media subsystems in space-constrained handheld devices.

For engineers reviewing the AP7343D-295FS4-7B datasheet, AP7343D-295FS4-7B pinout, AP7343D-295FS4-7B application, or AP7343D-295FS4-7B equivalent, key selection criteria include dropout voltage at 300mA (0.22–0.29V for V_OUT = 2.95V), thermal resistance (R_θJA = 237°C/W in X2-DFN1010-4), EN logic thresholds (V_IL ≤ 0.5V, V_IH ≥ 1.3V), and built-in discharge functionality.

Technical Context

The AP7343D integrates a CMOS-based pass transistor, precision voltage reference, error amplifier, current-limit protection, and thermal shutdown circuitry. Its enable input (EN) provides precise on/off control with <1.0µA leakage and defined logic thresholds, supporting low-power sequencing in battery-operated systems.

It features an internal auto-discharge path (enabled by the 'D' suffix) that actively pulls V_OUT to GND when disabled, eliminating residual voltage hold-up - critical for multi-rail power domains requiring controlled power-down timing and avoiding latch-up in downstream logic.

Key Specifications

Pinout & Package

AP7343D-295FS4-7B uses the X2-DFN1010-4 (Type B) package: 1.0mm × 1.0mm, 0.4mm pitch, 4-pin leadless DFN with exposed thermal pad (EP). The EP must be connected to PCB ground plane 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 MCP1700T-3002E/MB and XC6210B295MR-G, the AP7343D-295FS4-7B uniquely combines discharge functionality, 75dB PSRR, and 237°C/W thermal resistance in a 1.0mm² footprint - making it optimal for compact, multi-rail, battery-sensitive designs requiring controlled power sequencing.

Availability

AP7343D-295FS4-7B is available at Aetrix Electronics and suitable for smartphone camera modules, Wi-Fi/Bluetooth RF supplies, portable media player audio codecs, and industrial handheld scanner logic rails requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for AP7343D-295FS4-7B 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 belongs to Diodes' high-performance LDO portfolio, designed specifically for low-noise, high-PSRR power delivery in portable and battery-powered consumer electronics where board space, thermal efficiency, and sequencing control are critical.

FAQ

What is the purpose of the 'D' suffix in AP7343D-295FS4-7B?

The 'D' denotes integrated auto-discharge functionality: when the EN pin is driven low, an internal NMOS transistor actively discharges the V_OUT capacitor to GND within 100µs. This prevents residual voltage from interfering with downstream logic states during power-down sequences - eliminating the need for external discharge resistors and reducing BOM count.

Can AP7343D-295FS4-7B operate from a 3.0V input supply?

Yes. With a 2.95V output and maximum dropout of 0.29V at 300mA, the minimum required input is 3.24V. A 3.0V supply falls below this threshold and will cause dropout - the regulator cannot maintain regulation. For 3.0V input, select a lower-V_OUT variant (e.g., AP7343D-285FS4-7B) or verify actual load current, as dropout decreases at lighter loads.

Is the X2-DFN1010-4 (Type B) package thermally compatible with standard reflow profiles?

Yes. The X2-DFN1010-4 (Type B) package is qualified for JEDEC J-STD-020 moisture sensitivity level 1 (MSL1) and supports standard Pb-free reflow profiles (peak 260°C). Thermal pad soldering is mandatory: use ≥80% solder coverage on the EP, connect to a solid GND plane, and ensure ≥6 thermal vias (0.3mm diameter) beneath the pad to achieve specified R_θJB = 85.7°C/W.

How does the AP7343D handle short-circuit conditions?

Under V_OUT-to-GND short, the AP7343D limits output current to ~55mA via fold-back current limiting and activates thermal shutdown if junction temperature exceeds +150°C. Recovery is automatic once fault is removed and die temperature drops below +130°C hysteresis. This dual protection prevents damage during accidental shorts or PCB assembly errors.