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AP7331-18WG-7

DIOAP7331-18WG-7

Diodes Incorporated
Linear Voltage Regulator IC Positive Fixed 1 Output 300mA SOT-25
Active572 in stock

Overview

The AP7331-18WG-7 is a 300mA low dropout (LDO) linear regulator that provides a fixed 1.8V output from an input voltage range of 2V to 6V. It is designed with a high-speed response to line and load transients, making it suitable for noise-sensitive digital and analog circuits. The device includes integrated protection features such as current limiting, short-circuit protection, and thermal shutdown to ensure system reliability.

Why Choose This Part

This regulator is stable with low ESR ceramic output capacitors as small as 1uF, reducing total PCB BOM cost and area. It features a low quiescent current of 65uA and a shutdown current of just 1uA, extending battery life in portable applications. The wide 2V to 6V input range allows for operation from 1-cell Li-ion batteries or 5V USB rails.

Applications

Microcontroller I/O Rails
Providing a stable 1.8V supply for low-voltage MCU cores and digital interfaces in battery-powered devices.
Low-Power Wireless Modules
Powering Bluetooth Low Energy (BLE) or Zigbee radios that require clean voltage and low quiescent current during sleep modes.
Portable Media Players
Regulating power for audio decoders and display controllers where a small SOT-25 footprint is required.
Sensor Instrumentation
Supplying low-noise power to analog-to-digital converters and sensitive transducers.

Key Specifications

PSRR 65dB (100Hz)
Output Type Fixed
Mounting Type Surface Mount
Package / Case SC-74A, SOT-753
Control Features Enable
Current - Output 300mA
Protection Features Over Current, Over Temperature
Number of Regulators 1
Output Configuration Positive
Operating Temperature -40degC ~ 85degC
Voltage - Input (Max) 6V
Current - Supply (Max) 85 uA
Supplier Device Package SOT-25
Current - Quiescent (Iq) 75 uA
Voltage - Output (Min/Fixed) 1.8V

Getting Started

To implement this LDO, place a 1uF ceramic capacitor as close as possible to both the VIN and VOUT pins relative to the ground plane. Ensure the EN pin is pulled high for operation or low to enter the ultra-low current shutdown mode. For high-current loads, calculate the thermal rise based on the SOT-25 package's thermal resistance to prevent hitting the thermal shutdown threshold.

Also Consider

MCP1700T-1802E/TT MCHPMicrochip Technology - Lower quiescent current of 1.6uA for extremely power-constrained battery applications.
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