Diodes Incorporated AP7343-18W5-7

Overview

AP7343-18W5-7 from Diodes Incorporated is a 300mA, 1.8V fixed-output low-dropout linear regulator with ±1% output voltage accuracy, 75dB PSRR at 1kHz, and 60µV_rms output noise (10Hz–100kHz). Built on a CMOS process, it features enable control, thermal shutdown, and short-circuit protection, and is optimized for RF supply rails in space-constrained portable electronics.

For engineers reviewing the AP7343-18W5-7 datasheet, AP7343-18W5-7 pinout, AP7343-18W5-7 application, or AP7343-18W5-7 equivalent, key selection criteria include its 1.7V–5.25V input range, 35µA quiescent current, SOT25 package footprint, and guaranteed 300mA output under low dropout conditions - critical for battery-powered RF subsystems requiring clean, stable biasing.

Technical Context

The AP7343-18W5-7 integrates a precision voltage reference, error amplifier, current-limit circuit, and CMOS pass transistor to deliver tightly regulated 1.8V output. Its architecture supports fast load transient response (<100µs recovery) and high power-supply rejection across 100Hz–100kHz, enabled by internal compensation and compatibility with 1µF ceramic output capacitors.

Enable logic operates with TTL-compatible thresholds (EN low ≤0.5V, high ≥1.3V), and the device includes fold-back current limiting (~55mA short-circuit clamp) and thermal shutdown at +150°C with +20°C hysteresis. It lacks built-in output discharge (non-D variant), confirmed by ordering code "W5" (SOT25) and absence of "D" prefix.

Key Specifications

Pinout & Package

AP7343-18W5-7 is packaged in the SOT25 (TSOT-23-5) surface-mount package - a 2.9mm × 1.6mm × 1.1mm 5-pin leaded outline with exposed pad for thermal enhancement. Pin 5 is NC (no connection); the exposed pad must be connected to GND via large copper area for optimal thermal dissipation but not used as primary GND electrode.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-1802E/TT and XC6206P182MR-G, AP7343-18W5-7 uniquely balances 300mA drive, 75dB PSRR, 60µV_rms noise, and enable control in the compact SOT25 package - making it the preferred choice for RF and imaging subsystems demanding both performance and space efficiency.

Availability

AP7343-18W5-7 is available at Aetrix Electronics and suitable for RF power amplifier biasing, mobile camera ISP core supplies, wireless adapter baseband regulation, and portable media player audio codec powering requiring stable component supply across production volumes.

Supply support for AP7343-18W5-7 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 devices, with emphasis on power management, signal integrity, and connectivity solutions for consumer, industrial, and automotive markets.

The AP7343 series belongs to Diodes' high-performance LDO portfolio, engineered specifically for low-noise, high-PSRR regulation in battery-powered portable electronics - especially where RF sensitivity, small footprint, and precise voltage accuracy are critical.

FAQ

What is the maximum allowable input voltage for AP7343-18W5-7?

The absolute maximum input voltage is 6.0V, but the recommended operating range is 1.7V to 5.25V. Exceeding 5.25V risks violating safe operating area limits and may trigger thermal shutdown or degrade long-term reliability, even if within absolute max ratings.

Does AP7343-18W5-7 include output discharge functionality?

No. AP7343-18W5-7 is the non-discharge variant (ordering code lacks "D" prefix). When disabled via EN pin, the output remains floating; an external bleed resistor or dedicated discharge FET is required if rapid VOUT decay is needed.

Can AP7343-18W5-7 operate with a 1µF ceramic output capacitor?

Yes - the device is explicitly characterized and stable with 1µF X5R/X7R ceramic capacitors. Layout best practice requires placing this capacitor within 2mm of VOUT and GND pins, using short wide traces to minimize ESL and ensure robust transient response.

What thermal derating applies when using AP7343-18W5-7 in a 4-layer PCB without thermal vias?

In a standard JEDEC High-K 2×2-inch board (1oz planes, 2oz traces), R_θJA is 179°C/W for SOT25. Without thermal vias to inner ground planes, junction temperature rise exceeds safe limits above ~150mA at +85°C ambient - derate output current or add ≥4 thermal vias under the exposed pad.