Diodes Incorporated AP2127K-1.2TRG1

Overview

AP2127K-1.2TRG1 from Diodes Incorporated is a 300mA, 1.2V fixed-output CMOS low-dropout (LDO) regulator in SOT-23-5 package, featuring 170mV dropout at 300mA (V_OUT = 3.3V), ±2% output voltage accuracy, and 60μV_RMS ultra-low noise-designed for power-sensitive applications including notebook CPU core logic and embedded microcontroller I/O rails.

For engineers reviewing the AP2127K-1.2TRG1 datasheet, AP2127K-1.2TRG1 pinout, AP2127K-1.2TRG1 application, or AP2127K-1.2TRG1 equivalent, key selection criteria include its 2.5V–6V input range, 60μA typical quiescent current, integrated shutdown control with 0.1μA standby mode, and compatibility with 1μF ceramic input/output capacitors for compact, stable battery-powered designs.

Technical Context

The AP2127K-1.2TRG1 employs a PMOS pass transistor architecture enabling low dropout and high PSRR (68dB @ 1kHz). Its internal 0.8V reference feeds a precision error amplifier that regulates output against line, load, and temperature variations across –40°C to +85°C.

It integrates active shutdown with auto-discharge (60Ω R_DS(ON)), thermal shutdown (+165°C), and short-circuit current limiting (50mA), all operating without external components beyond 1μF C_IN/C_OUT. The SOT-23-5 package includes dedicated Shutdown and GND pins for robust enable sequencing and noise isolation.

Key Specifications

Pinout & Package

SOT-23-5 package with exposed pad (thermal enhancement), footprint compatible with JEDEC MO-178AA. Pin 1 = VIN, Pin 2 = GND, Pin 3 = VOUT, Pin 4 = Shutdown, Pin 5 = NC/ADJ (no connection for fixed-version variants).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-1202E/TT and XC6206P122MR-G, the AP2127K-1.2TRG1 delivers higher output current (300mA vs. ≤250mA), integrated shutdown with auto-discharge, and full thermal/short-circuit protection-making it suitable for dynamically controlled, thermally constrained, and safety-critical applications where reliability and feature completeness outweigh minimal IQ savings.

Availability

AP2127K-1.2TRG1 is available at Aetrix Electronics and suitable for notebook computers, industrial sensor nodes, wearable health monitors, and mobile baseband power systems requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for AP2127K-1.2TRG1 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 solutions, with design centers in Asia, Europe, and the U.S., and ISO/TS 16949-certified manufacturing facilities.

The AP2127 Series belongs to Diodes' high-performance LDO portfolio targeting battery-powered and noise-sensitive applications, emphasizing ultra-low noise, low dropout, and seamless integration into compact, thermally constrained PCB layouts.

FAQ

What is the minimum input voltage required for AP2127K-1.2TRG1 to maintain regulation?

The AP2127K-1.2TRG1 requires a minimum input voltage of 2.5V per its recommended operating conditions. At 300mA load and 1.2V output, the dropout voltage is not explicitly listed in the datasheet for this specific V_OUT, but extrapolation from adjacent 1.0V/1.5V data indicates ~1300mV–1500mV; thus, VIN ≥ 2.5V ensures reliable operation across temperature and process variation.

Can AP2127K-1.2TRG1 be used with a 10μF output capacitor?

Yes-the AP2127K-1.2TRG1 is stable with ceramic capacitors ≥1μF and does not require ESR damping. A 10μF X5R/X7R MLCC improves transient response and reduces output ripple further, especially under dynamic loads like burst-mode wireless transmission, with no stability risk.

Is the Shutdown pin compatible with 1.8V logic levels?

Yes-the Shutdown pin has a guaranteed logic-high threshold of 1.5V (min) and logic-low threshold of 0.5V (max), making it fully compatible with 1.8V GPIO outputs. No level-shifting circuitry is needed when interfacing with modern low-voltage microcontrollers.

Does AP2127K-1.2TRG1 require an external feed-forward capacitor?

No-feed-forward capacitors are only required for the adjustable (ADJ) version of the AP2127. The AP2127K-1.2TRG1 is a fixed-output variant with internally trimmed feedback, so no external ADJ network or feed-forward capacitor is needed or recommended.