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Diodes Incorporated AP2127K-4.2TRG1
- Part No.:
- AP2127K-4.2TRG1
- Manufacturer:
- Diodes Incorporated
- Package:
- SC-74A, SOT-753
- Datasheet:
-
AP2127K-4.2TRG1.pdf
- Description:
- IC REG LINEAR 4.2V 300MA SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:3,342
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Product details
Overview
AP2127K-4.2TRG1 from Diodes Incorporated is a 300mA, 4.2V fixed-output CMOS low-dropout (LDO) regulator in SOT-23-5 package, featuring 170mV dropout at 300mA, ±2% output voltage accuracy, and 60μVRMS output noise-designed for stable power delivery in portable battery-powered systems such as notebook motherboard core rails.
For engineers reviewing the AP2127K-4.2TRG1 datasheet, AP2127K-4.2TRG1 pinout, AP2127K-4.2TRG1 application, or AP2127K-4.2TRG1 equivalent, key selection criteria include dropout performance at full load, thermal behavior in SOT-23-5, shutdown control timing, RMS noise under light-load conditions, and compatibility with 1μF ceramic input/output capacitors.
Technical Context
The AP2127K-4.2TRG1 uses a PMOS pass transistor architecture enabling ultra-low dropout (170mV @ 300mA for VOUT = 4.2V) and high PSRR (68dB @ 1kHz). Its internal 0.8V reference feeds a precision error amplifier that maintains regulation across –40°C to +85°C ambient.
It integrates active shutdown control with 0.1μA standby current, auto-discharge MOSFET (RDS(ON) = 60Ω), over-temperature protection (trip at +165°C), and short-circuit current limiting (50mA). The device operates from 2.5V to 6V input and requires no external compensation with 1μF X7R/X5R MLCCs on both VIN and VOUT.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | Fixed 4.2V ±2% - ensures stable bias for 4.2V Li-ion charging management ICs and USB PD sink rails. |
| Max Output Current | 300mA continuous - supports moderate-power logic, sensors, and RF front-end biasing without thermal derating in SOT-23-5. |
| Dropout Voltage | 170mV @ 300mA - enables operation down to VIN = 4.37V, critical for maintaining regulation during battery discharge. |
| Output Noise | 60μVRMS (10Hz–100kHz) - meets low-noise requirements for ADC references and RF synthesizer VCO supplies. |
| PSRR | 68dB @ 1kHz - suppresses switching noise from upstream DC/DC converters feeding the LDO input. |
| Quiescent Current | 60μA typical - extends battery life in always-on subsystems like real-time clocks and wake-up controllers. |
| Shutdown Current | 0.1μA - enables deep-sleep modes in portable devices with fast wake-up via active-high SHDN pin. |
Pinout & Package
SOT-23-5 package: 2.9mm × 1.6mm × 1.1mm body, exposed pad for thermal enhancement (to be connected to GND), RoHS-compliant, halogen-free "Green" construction.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VIN (Pin 2) | Power Input | Accepts 2.5V–6V supply; requires 1μF ceramic decoupling placed adjacent to pin for stability. |
| GND (Pin 1) | Ground Reference | Primary return path for load current and internal bias; connects to exposed thermal pad. |
| VOUT (Pin 3) | Regulated Output | Delivers 4.2V ±2% to load; stable with ≥1μF ceramic capacitor; includes integrated 60Ω discharge FET. |
| Shutdown (Pin 4) | Enable Control | Active-high logic input; drives device into 0.1μA standby when pulled low; internal 3MΩ pull-down. |
| NC/ADJ (Pin 5) | No Connection | Not bonded in fixed-output variants; left unconnected per datasheet guidance for AP2127K-4.2TRG1. |
Key Features
| Feature | Design Value |
|---|---|
| Low-noise regulation | 60μVRMS output noise enables clean power for precision analog circuits without external filtering. |
| Fast soft-start | 50μs startup time prevents inrush current and output overshoot during power-up sequences. |
| Thermal robustness | +165°C over-temperature shutdown with +30°C hysteresis ensures reliable operation under sustained overload. |
| Ceramic capacitor compatible | Stable with 1μF X7R/X5R MLCCs on input and output-reduces BOM count and PCB area vs. tantalum solutions. |
| Auto-output discharge | Integrated 60Ω MOSFET discharges VOUT capacitance rapidly upon shutdown, meeting system-level power sequencing requirements. |
Applications
| USB Power Delivery Sink Rail | Notebook Motherboard Core Logic |
|---|---|
Use Scenario: Supplies regulated 4.2V to USB PD sink controller ICs and Type-C port power switches. IC Role / Device Role / Timing Role: Primary post-regulator delivering precise 4.2V rail with fast transient response to handle dynamic load steps during negotiation. Use Value: ±2% accuracy and 68dB PSRR ensure compliance with USB PD specification voltage tolerance and noise immunity. | Use Scenario: Powers DDR memory termination (VTT) or chipset I/O buffers requiring stable 4.2V bias. IC Role / Device Role / Timing Role: Low-noise, low-dropout LDO providing clean auxiliary voltage for high-speed digital interfaces. Use Value: 60μVRMS noise and 170mV dropout maintain signal integrity and timing margin during battery sag conditions. |
| Portable Medical Sensor Module | Industrial Handheld Terminal |
Use Scenario: Powers analog front-end (AFE) and low-power MCU in battery-operated glucose meters or pulse oximeters. IC Role / Device Role / Timing Role: Main system regulator delivering 4.2V to mixed-signal SoC with minimal self-heating in compact enclosure. Use Value: 0.1μA shutdown current extends shelf life; thermal shutdown protects against enclosure overheating during extended use. | Use Scenario: Supplies 4.2V to barcode scanner engine and display backlight driver in ruggedized handheld terminals. IC Role / Device Role / Timing Role: Robust local regulator handling wide input range (2.5V–6V) across Li-ion, USB, and adapter inputs. Use Value: Wide VIN range and 50mA short-circuit limit prevent latch-up during ESD events on exposed I/O ports. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar fixed-output LDO regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MCP1700T-4202E/TT | 250mA max output, 1.6μA quiescent current, no shutdown pin, SOT-23-3 package | Lacks enable control and auto-discharge; lower current rating limits use in higher-load scenarios | Select when ultra-low IQ dominates design priority and shutdown functionality is unnecessary. |
| Torex XC6206P422MR-G | 300mA output, 1.0μA IQ, no thermal shutdown, SOT-23-3 package | Missing over-temperature protection and soft-start; limited thermal capability in same footprint | Choose only for cost-sensitive, non-safety-critical applications where thermal margin is guaranteed externally. |
Compared with MCP1700T-4202E/TT and XC6206P422MR-G, the AP2127K-4.2TRG1 uniquely combines 300mA drive, active shutdown, auto-discharge, and thermal protection in a 5-pin SOT-23 package-enabling safer, more feature-complete power management in space-constrained portable designs.
Availability
AP2127K-4.2TRG1 is available at Aetrix Electronics and suitable for notebook motherboard power rails, USB PD sink implementations, and portable medical sensor modules requiring stable component supply with full traceability and long-term lifecycle support.
Supply support for AP2127K-4.2TRG1 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 company specializing in discrete, analog, and mixed-signal ICs, with emphasis on power management, signal integrity, and connectivity solutions.
The AP2127 series belongs to Diodes' high-performance LDO portfolio targeting battery-powered and noise-sensitive applications-designed to deliver low dropout, ultra-low noise, and robust protection features in miniature packages.
FAQ
What is the minimum input voltage required for AP2127K-4.2TRG1 to maintain regulation at 300mA load?
The minimum input voltage is 4.37V, calculated as VOUT + VDROP = 4.2V + 0.17V. At 300mA load and TA = +25°C, the dropout voltage is guaranteed ≤300mV, but typical performance is 170mV. Below 4.37V, output voltage drops linearly with input, entering dropout region.
Can AP2127K-4.2TRG1 be used with aluminum polymer capacitors instead of ceramic?
No-aluminum polymer capacitors typically exhibit higher ESR (>10mΩ) than the <10mΩ required for AP2127 stability. The device is characterized and guaranteed stable only with low-ESR ceramic capacitors (X7R/X5R, ≥1μF). Using polymer caps may cause oscillation or poor transient response.
Is the NC/ADJ pin (Pin 5) required to be tied to ground or left floating in AP2127K-4.2TRG1?
Pin 5 is not bonded internally in fixed-output versions and must be left unconnected (floating). The datasheet explicitly states "NC/ADJ" for this pin in fixed-voltage variants and confirms no connection is required-tying it to GND or any other node risks undefined behavior or damage.
Does AP2127K-4.2TRG1 support reverse current blocking when VIN is disconnected while VOUT remains powered?
No-the AP2127K-4.2TRG1 does not integrate reverse current blocking. When VIN is removed and VOUT is back-driven, current can flow from VOUT to VIN through the internal pass device's body diode. External reverse-blocking circuitry (e.g., series Schottky diode or ideal diode controller) is required for such fault conditions.
AP2127K-4.2TRG1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- SC-74A, SOT-753
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Output Configuration:
- Positive
- Output Type:
- Fixed
- Number of Regulators:
- 1
- Voltage - Input (Max):
- 6V
- Voltage - Output (Min/Fixed):
- 4.2V
- Voltage - Output (Max):
- -
- Voltage Dropout (Max):
- 0.3V @ 300mA
- Current - Output:
- 300mA
- Current - Quiescent (Iq):
- 90 µA
- Current - Supply (Max):
- -
- PSRR:
- 68dB ~ 54dB (100Hz ~ 10kHz)
- Control Features:
- -
- Protection Features:
- Over Current, Over Temperature
- Operating Temperature:
- -40°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-5
AP2127K-4.2TRG1 FAQ
1.How can I place an order for AP2127K-4.2TRG1 through Aetrix?
Please submit a Request for Quotation (RFQ) for AP2127K-4.2TRG1 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for AP2127K-4.2TRG1 reliable?
The price and inventory of AP2127K-4.2TRG1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AP2127K-4.2TRG1 is usually 5 days.
3.What payment methods are accepted for AP2127K-4.2TRG1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AP2127K-4.2TRG1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AP2127K-4.2TRG1?
AP2127K-4.2TRG1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AP2127K-4.2TRG1 order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for AP2127K-4.2TRG1?
For technical support, including AP2127K-4.2TRG1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AP2127K-4.2TRG1 requirements.
6.How does Aetrix verify that AP2127K-4.2TRG1 is sourced from the original manufacturer or authorized distributors?
All AP2127K-4.2TRG1 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that AP2127K-4.2TRG1 meets industry standards.
7.What is the process for return or replacement of AP2127K-4.2TRG1?
All AP2127K-4.2TRG1 units undergo pre-shipment inspection (PSI). If there is an issue with AP2127K-4.2TRG1, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The AP2127K-4.2TRG1 part is unused and in its original packaging.
Return procedure for AP2127K-4.2TRG1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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