EmbeddedRelated.com
Jacob Beningo
Live online course · Jacob Beningo
AI for Embedded Developers
$100 off for EmbeddedRelated readers until Nov 1 · 5 live sessions, Dec 7-11
Discount ends in
15days 19hrs 06min 33sec
Learn More →
    Parts    Positive LDO regulators Family    AP2127    AP2127K-1.8TRG1
AP2127K-1.8TRG1

DIOAP2127K-1.8TRG1

Diodes Incorporated
Linear Voltage Regulator IC Positive Fixed 1 Output 300mA SOT-23-5
Active161,569 in stock
Datasheet Digi-Key Compare Prices

Overview

The AP2127K-1.8TRG1 is a 300mA fixed output linear voltage regulator designed to provide a stable 1.8V supply from input voltages up to 6V. It is optimized for low-noise performance and high PSRR, making it suitable for sensitive analog and digital circuits. The device includes integrated protection features such as over-temperature and over-current limiting in a compact SOT-23-5 package.

Why Choose This Part

This LDO is compatible with low-ESR ceramic capacitors as small as 1uF for both input and output, reducing PCB footprint requirements. It features a fast 50us soft-start time and an integrated 60-ohm auto-discharge resistor to ensure controlled power-down cycles.

Applications

Microcontroller Core Power
Provides a clean 1.8V rail for low-voltage MCU cores and digital signal processing units.
RF and Wireless Modules
Utilizes its high PSRR of 68dB at 100Hz to minimize noise in sensitive wireless communication circuits.
Battery-Powered Handhelds
Leverages a low 60uA typical quiescent current to extend battery life in portable electronics.
Post-Regulation
Cleans up ripple from switching regulators for noise-sensitive ADC or DAC reference inputs.

Key Specifications

PSRR 68dB ~ 54dB (100Hz ~ 10kHz)
Output Type Fixed
Mounting Type Surface Mount
Package / Case SC-74A, SOT-753
Current - Output 300mA
Protection Features Over Current, Over Temperature
Number of Regulators 1
Output Configuration Positive
Operating Temperature -40degC ~ 85degC
Voltage - Input (Max) 6V
Voltage Dropout (Max) 0.7V @ 300mA
Supplier Device Package SOT-23-5
Current - Quiescent (Iq) 90 uA
Voltage - Output (Min/Fixed) 1.8V

Getting Started

To implement this regulator, place a 1uF ceramic capacitor close to the VIN and VOUT pins relative to the GND pin. Ensure the EN pin is pulled high to enable the device, or low to enter a 0.1uA shutdown state. For thermal management, maximize the copper area connected to the GND pin on the SOT-23-5 footprint.

Part of Positive LDO regulators family » AP2127

AP2127 Family

Comparing specs that differ across variants. The current part is highlighted.

Part Number PSRR Output Type Package Voltage Dropout (Max) Output V Stock
AP2127K-1.8TRG1 (this part) 100Hz Fixed SC-74A, SOT-753 0.7V 1.8V 161,569
AP2127N-2.8TRG1 100Hz Fixed 3-236 0.3V 2.8V 5,602
AP2127K-ADJTRG1 100Hz Adjustable SC-74A, SOT-753 0.3V 0.8V 117,414
AP2127K-3.3TRG1 100Hz Fixed SC-74A, SOT-753 0.3V 3.3V 85,540
AP2127N-1.5TRG1 100Hz Fixed 3-236 1V 1.5V 2,905
AP2127N-3.3TRG1 100Hz Fixed 3-236 0.3V 3.3V 3,326
AP2127K-2.8TRG1 100Hz Fixed SC-74A, SOT-753 0.3V 2.8V 16,557
AP2127K-3.0TRG1 100Hz Fixed SC-74A, SOT-753 0.3V 3V 6,578
AP2127N-3.0TRG1 100Hz Fixed 3-236 0.3V 3V 1,141
AP2127K-2.5TRG1 100Hz Fixed SC-74A, SOT-753 0.3V 2.5V 1,728

Also Consider

AP2112K-1.8TRG1 DIODiodes Incorporated - Offers similar 600mA output capability if higher current drive is required for the 1.8V rail.
TLV70218DBVR TITexas Instruments - A popular alternative with even lower quiescent current for ultra-low power applications.