Diodes Incorporated AP7343D-33W5-7

Overview

AP7343D-33W5-7 from Diodes Incorporated is a 300mA, 3.3V fixed-output low-dropout linear regulator with high PSRR (75dB at 1kHz), ultra-low output noise (60µV_rms, 10Hz–100kHz), ±1% output voltage accuracy, and enable-controlled shutdown. Built on CMOS process, it delivers stable power to RF supplies and camera modules in space-constrained portable electronics using its SOT25 package.

For engineers reviewing the AP7343D-33W5-7 datasheet, AP7343D-33W5-7 pinout, AP7343D-33W5-7 application, or AP7343D-33W5-7 equivalent, key selection criteria include dropout voltage (≤0.29V at 300mA), quiescent current (35µA typ), thermal shutdown threshold (+150°C), and EN logic compatibility (1.3V high threshold).

Technical Context

The AP7343D-33W5-7 integrates a precision voltage reference, error amplifier, current-limit circuit, and thermal shutdown protection within a single CMOS LDO architecture. Its enable input (EN) provides precise on/off control with 0.5V max low threshold and 1.3V min high threshold, supporting system-level power sequencing.

It features built-in discharge functionality (denoted by "D" suffix), actively pulling VOUT to GND during shutdown via a 30Ω internal N-channel switch. This prevents residual voltage hold-up in multi-rail systems and eliminates need for external bleed resistors in battery-powered applications.

Key Specifications

Pinout & Package

AP7343D-33W5-7 uses the SOT25 (SC-74A) 5-pin surface-mount package - compact (2.9mm × 1.6mm × 1.1mm), thermally enhanced with exposed pad connected to GND for improved heat dissipation (R_θJA = 179°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700-3302E/TO and XC6210B332MR-G, the AP7343D-33W5-7 uniquely combines 300mA drive, 75dB PSRR, and integrated discharge in SOT25 - enabling robust RF and imaging power delivery without external components or performance trade-offs.

Availability

AP7343D-33W5-7 is available at Aetrix Electronics and suitable for RF power amplifiers, CMOS image sensors, wireless adapter interfaces, and portable media player audio codecs requiring stable component supply, long-term lifecycle assurance, and automotive-grade reliability derivatives (AP7343Q).

Supply support for AP7343D-33W5-7 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 ICs, with design centers in Asia, Europe, and the U.S., serving consumer, industrial, computing, and automotive markets.

The AP7343 series belongs to Diodes' high-performance LDO portfolio, engineered specifically for noise-sensitive, battery-powered portable electronics demanding low IQ, high PSRR, and fast transient response.

FAQ

What is the minimum input voltage required for AP7343D-33W5-7 to maintain regulation at 300mA?

The minimum input voltage is calculated as VOUT + dropout voltage. At 300mA and +25°C, dropout is 0.22V (typ) to 0.31V (max) in SOT25. Thus, VIN must be ≥3.52V to guarantee 3.3V output under full load. Below this, output collapses proportionally per the dropout curve in the datasheet.

Does AP7343D-33W5-7 require an external discharge resistor?

No. The "D" suffix denotes integrated discharge functionality: a 30Ω N-channel MOSFET connects VOUT to GND when EN is low. This eliminates need for external resistors, reduces board area, and ensures rapid VOUT decay (<1ms for 1µF load) without leakage current penalties.

Can AP7343D-33W5-7 operate with ceramic output capacitors smaller than 1µF?

Yes - the device is stable with ≥0.47µF ceramic capacitors. However, 1µF is recommended to meet transient response specs (≤2% deviation for 1mA↔300mA step). Capacitors below 0.47µF risk instability or excessive ringing due to insufficient phase margin.

How does thermal performance differ between SOT25 and X2-DFN1010-4 packages?

SOT25 has R_θJA = 179°C/W; X2-DFN1010-4 (Type B) is 237°C/W - meaning SOT25 dissipates heat more effectively on standard PCBs. The SOT25's lower junction-to-ambient resistance allows higher continuous current at ambient temperatures up to +85°C without derating.