Diodes Incorporated AP7343-185W5-7

Overview

AP7343-185W5-7 from Diodes Incorporated is a 300mA, 1.85V fixed-output low-dropout linear regulator with ±1% output voltage accuracy, 75dB PSRR at 1kHz, and 60µV_rms output noise (10Hz–100kHz). Built on CMOS process, it features enable control, thermal shutdown, and short-circuit protection. It powers RF supply rails in compact portable devices where low quiescent current (35µA) and high transient response are critical.

For engineers reviewing the AP7343-185W5-7 datasheet, AP7343-185W5-7 pinout, AP7343-185W5-7 application, or AP7343-185W5-7 equivalent, key selection criteria include dropout voltage at 300mA (0.35V typ. for 1.85V output), EN logic thresholds (0.5V low / 1.3V high), thermal resistance in SOT25 (179°C/W), and compatibility with 1µF ceramic input/output capacitors.

Technical Context

The AP7343-185W5-7 integrates a precision voltage reference, error amplifier, current-limit circuit, and NMOS pass transistor in a CMOS-based LDO architecture. Its enable input directly controls the pass device gate, supporting fast turn-on/turn-off with controlled slew rates.

It delivers stable 1.85V output across –40°C to +85°C ambient, with line regulation ≤0.1%/V and load regulation ≤30mV from 1mA to 300mA. Thermal shutdown activates at +150°C with +20°C hysteresis, and short-circuit current is clamped to ~55mA.

Key Specifications

Pinout & Package

SOT25 (5-pin, 2.9mm × 1.6mm) package with exposed thermal pad (EP); pin 1 = VIN, pin 2 = GND, pin 3 = EN, pin 4 = VOUT, pin 5 = NC (no connection). EP must be connected to PCB ground plane for optimal thermal performance (R_θJB = 79.2°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1703T-1852E/MB and XC6219B185MR-G, the AP7343-185W5-7 uniquely combines ±1% accuracy, 75dB PSRR, 60µV_rms noise, and full thermal/short-circuit protection in SOT25-making it optimal for RF and mixed-signal subsystems demanding both precision and robustness.

Availability

AP7343-185W5-7 is available at Aetrix Electronics and suitable for RF power amplifier biasing, camera ISP powering, Bluetooth SoC core rails, and portable media player audio codec applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for AP7343-185W5-7 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 manufacturer specializing in discrete, analog, and mixed-signal ICs, with emphasis on power management, signal integrity, and connectivity solutions for consumer, industrial, and automotive markets.

The AP7343 series belongs to Diodes' high-PSRR, low-noise LDO product line, designed specifically for noise-sensitive portable electronics requiring ultra-stable, low-quiescent-current voltage regulation in minimal footprint packages.

FAQ

What is the minimum input voltage required for AP7343-185W5-7 to regulate 1.85V at 300mA?

The minimum input voltage is determined by dropout: at 300mA, typical dropout is 0.35V, so VIN(min) = 1.85V + 0.35V = 2.2V. Absolute minimum VIN per datasheet is 1.7V, but regulation fails below 2.2V under full load. For guaranteed 300mA output, maintain VIN ≥2.25V across temperature and tolerance.

Can AP7343-185W5-7 be used without an enable signal?

Yes-pin 3 (EN) must not be left floating. To operate continuously, tie EN directly to VIN. This ensures the internal NMOS pass device remains fully enhanced. Do not connect EN to VOUT or use resistive dividers; only direct VIN or clean logic-level signals meet the 1.3V minimum high threshold.

Is the exposed pad (EP) on the SOT25 package electrically connected?

No-the EP is thermally conductive but electrically isolated. It must be soldered to a PCB copper pour tied to GND for heat dissipation (R_θJB = 79.2°C/W), but it serves no electrical function and must not be used as a GND terminal for current return paths.

Does AP7343-185W5-7 include output discharge functionality?

No-AP7343-185W5-7 is the non-discharge variant (ordering code lacks "D"). When disabled via EN, VOUT remains floating and discharges only through load leakage or external bleed resistors. For active discharge, select AP7343D-185W5-7, which adds an internal NMOS switch (R_ON ≈30Ω) between VOUT and GND.