Diodes Incorporated AP2127N3-1.2TRG1

Overview

AP2127N3-1.2TRG1 from Diodes Incorporated is a fixed-output 1.2V, 300mA CMOS low-dropout linear regulator in SOT-23-3 package, featuring ±2% output voltage accuracy, 60μA typical quiescent current, 170mV dropout at 300mA (for 3.3V version; 1.2V version dropout is 1200–1300mV), and 60μVRMS output noise - optimized for power-sensitive portable electronics requiring stable low-noise biasing.

For engineers reviewing the AP2127N3-1.2TRG1 datasheet, AP2127N3-1.2TRG1 pinout, AP2127N3-1.2TRG1 application, or AP2127N3-1.2TRG1 equivalent, key selection criteria include input voltage range (2.5V–6V), thermal shutdown threshold (+165°C), soft-start time (50μs), auto-discharge R_DS(ON) (60Ω), and compatibility with 1μF ceramic input/output capacitors.

Technical Context

The AP2127N3-1.2TRG1 implements a PMOS pass transistor architecture enabling ultra-low quiescent current (60μA typ) and fast transient response without external compensation. Its internal 0.8V reference feeds a precision error amplifier that maintains regulation across –40°C to +85°C ambient temperature.

Unlike NMOS-based LDOs, this CMOS design eliminates the need for a charge pump, reducing EMI and simplifying PCB layout. The integrated shutdown logic accepts TTL-compatible enable signals (V_SHDN(H) ≥1.5V, V_SHDN(L) ≤0.5V), and the auto-discharge MOSFET actively pulls down VOUT during disable to prevent hold-up voltage in multi-rail systems.

Key Specifications

Pinout & Package

SOT-23-3 package: 3-pin surface-mount plastic package with exposed pad (not electrically connected), footprint compatible with JEDEC TO-236AB, thermal resistance θ_JA = 250°C/W (no copper pour).

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 AP2127N3-1.2TRG1 uniquely combines 300mA drive capability, integrated auto-discharge, and full thermal protection - making it optimal for battery-powered systems requiring robustness, fast power-down, and reliable operation across industrial temperature ranges.

Availability

AP2127N3-1.2TRG1 is available at Aetrix Electronics and suitable for wearable health sensors, industrial IoT edge nodes, USB-C peripherals, and automotive cabin infotainment modules requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant sourcing.

Supply support for AP2127N3-1.2TRG1 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 emphasis on power management, signal integrity, and protection devices for industrial, computing, and consumer markets.

The AP2127 series belongs to Diodes' high-performance LDO portfolio designed specifically for battery-powered portable electronics demanding ultra-low noise, low quiescent current, and fast transient response in miniature packages.

FAQ

What is the minimum input voltage required for regulation at 1.2V output?

The AP2127N3-1.2TRG1 requires VIN ≥ 2.5V per datasheet specifications. At 300mA load, its dropout voltage is 1200–1300mV for 1.2V output, meaning VIN must be ≥ 2.4V to maintain regulation - but the absolute minimum specified input is 2.5V to guarantee performance across temperature and process variation.

Does AP2127N3-1.2TRG1 require an external shutdown pull-up resistor?

No. The shutdown pin is internally pulled down with 3MΩ resistance; only a logic-high signal (≥1.5V) is needed to enable the device. No external pull-up resistor is required, simplifying design and reducing component count in space-constrained layouts.

Can AP2127N3-1.2TRG1 be used with ceramic capacitors smaller than 1μF?

No. The datasheet explicitly specifies stability with ≥1μF X5R/X7R ceramic capacitors on both input and output. Using smaller values risks instability, oscillation, or degraded PSRR and transient response - confirmed by frequency-domain stability analysis in the application notes.

Is the SOT-23-3 package thermally enhanced with an exposed pad?

No. The SOT-23-3 variant (AP2127N3-xxx) does not include an exposed thermal pad. Its θ_JA is rated at 250°C/W with no copper pour; thermal performance relies solely on PCB copper area connected to GND pin (Pin 2), unlike the SOT-23-5 version which features an exposed pad for improved heat dissipation.