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MIC39100-3.3WS

MCHPMIC39100-3.3WS

Microchip Technology
Linear Voltage Regulator IC Positive Fixed 1 Output 1A SOT-223-3
Active61,394 in stock
Datasheet Digi-Key Mouser Compare Prices

Overview

The MIC39100-3.3WS is a high-current, low-dropout voltage regulator capable of providing a 1A output at a fixed 3.3V. It is designed for applications requiring a low dropout voltage (maximum 0.63V at 1A) and fast transient response, making it suitable for modern digital logic and processor power supplies. The device includes robust protection features such as reversed-battery and reversed-leakage protection.

Why Choose This Part

This regulator offers a very low dropout voltage of 0.63V at its full 1A load, which minimizes power dissipation and allows for operation from narrow input-to-output voltage margins. It features comprehensive protection including thermal shutdown, current limiting, and unique reversed-battery protection. The SOT-223 package provides a balance of small surface-mount footprint and sufficient thermal performance for mid-range power tasks.

Applications

Post-Regulator for Switching Power Supplies
Provides a clean 3.3V rail by filtering high-frequency noise from upstream DC-DC converters.
PC Add-In Cards
Used on expansion cards to derive 3.3V logic power from standard computer bus voltages.
Low-Voltage Digital Logic
Powers microcontrollers and FPGAs that require a stable 3.3V supply with up to 1A of current capacity.
Battery-Powered Systems
Utilizes low dropout characteristics and reversed-battery protection to extend runtime and prevent damage from incorrect battery insertion.

Key Specifications

Output Type Fixed
Mounting Type Surface Mount
Package / Case TO-261-4, TO-261AA
Current - Output 1A
Protection Features Over Current, Over Temperature, Reverse Polarity
Number of Regulators 1
Output Configuration Positive
Operating Temperature -40degC ~ 125degC
Voltage - Input (Max) 16V
Voltage Dropout (Max) 0.63V @ 1A
Supplier Device Package SOT-223-3
Voltage - Output (Min/Fixed) 3.3V

Getting Started

When designing with the MIC39100-3.3WS, ensure a minimum output capacitor is used for stability as specified in the datasheet, typically a 10uF or larger tantalum or electrolytic capacitor. For thermal management, provide adequate copper area on the PCB connected to the SOT-223 tab to dissipate heat at high current loads. Since this is a fixed 3.3V version, no external resistor divider is required for voltage setting.

Also Consider

LM1117-3.3 TITexas Instruments - A widely available industry-standard 3.3V LDO, though it typically has a higher dropout voltage of around 1.1V to 1.2V.
AZ1117C-3.3 DIODiodes Incorporated - A cost-effective 3.3V regulator in an SOT-223 package suitable for less demanding dropout requirements.
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