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Diodes Incorporated AP2129K-1.2TRG1
- Part No.:
- AP2129K-1.2TRG1
- Manufacturer:
- Diodes Incorporated
- Package:
- SC-74A, SOT-753
- Datasheet:
-
AP2129K-1.2TRG1.pdf
- Description:
- IC REG LINEAR 1.2V 300MA SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:1,380
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Product details
Overview
AP2129K-1.2TRG1 from Diodes Incorporated is a 300mA, fixed-output 1.2V CMOS low-dropout (LDO) regulator in SOT-23-5 package, featuring 60µA typical quiescent current, 60µVrms output noise, ±2% output voltage accuracy, and 65dB PSRR at 1kHz. It delivers stable power to noise-sensitive analog and RF circuitry in portable electronics with tight voltage tolerance and fast 50µs soft-start.
For engineers reviewing the AP2129K-1.2TRG1 datasheet, AP2129K-1.2TRG1 pinout, AP2129K-1.2TRG1 application, or AP2129K-1.2TRG1 equivalent, key selection criteria include dropout voltage at 300mA (600mV), shutdown current (0.1µA), thermal shutdown threshold (+165°C), and compatibility with 1µF ceramic input/output capacitors.
Technical Context
The AP2129K-1.2TRG1 uses a CMOS pass transistor architecture with internal 0.8V reference and precision feedback network to maintain regulated 1.2V output across 1mA–300mA load range. Its UVLO circuit disables regulation below 1.8V input, while foldback current limiting and thermal shutdown protect against overloads and junction overheating.
It integrates an active discharge MOSFET (RDS(ON) = 60Ω) that pulls VOUT to GND during shutdown, preventing floating outputs in battery-powered systems. The 3MΩ internal pull-down on the Shutdown pin ensures default-disable behavior without external components.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | Fixed 1.2V ±2% - ensures stable core voltage for 1.2V logic rails and low-voltage analog sensors |
| Max Output Current | 450mA peak - supports transient loads beyond nominal 300mA rating without latch-off |
| Dropout Voltage | 600mV @ 300mA - enables operation down to 1.8V input, suitable for single-cell Li-ion or dual-cell alkaline systems |
| PSRR | 65dB @ 1kHz - suppresses switching noise from upstream DC/DC converters feeding sensitive ADCs or PLLs |
| Output Noise | 60µVrms (10Hz–100kHz) - meets low-noise requirements for RF front-ends and precision instrumentation amplifiers |
| Quiescent Current | 60µA typical - extends battery life in always-on monitoring circuits such as IoT sensor nodes |
| Shutdown Current | 0.1µA - enables ultra-low-power deep-sleep modes in portable devices |
Pinout & Package
AP2129K-1.2TRG1 is housed in a RoHS-compliant, lead-free SOT-23-5 package (2.9mm × 1.6mm × 1.1mm), optimized for space-constrained PCB layouts and reflow-compatible assembly.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Shutdown) | Active-high enable control | Logic high (≥1.5V) enables regulation; logic low (≤0.4V) disables output and activates 60Ω discharge path |
| 2 (GND) | Power ground reference | Common return path for input, output, and internal bias circuits; requires low-impedance PCB connection |
| 3 (VIN) | Input voltage supply | Accepts 1.8V–6V input; must be decoupled with ≥1µF ceramic capacitor close to pin |
| 4 (VOUT) | Regulated output | Delivers fixed 1.2V ±2%; requires ≥1µF ceramic capacitor to ensure stability and transient response |
| 5 (ADJ/NC) | Adjust pin / No connection | No connection in fixed-output variants; left unconnected - not internally tied or biased |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low noise regulation | 60µVrms output noise enables direct powering of RF transceivers and high-resolution ADCs without additional filtering |
| Fast soft-start | 50µs startup time prevents inrush current spikes and avoids brown-out in cascaded power domains |
| Integrated output discharge | 60Ω internal MOSFET actively discharges VOUT during shutdown, eliminating need for external bleed resistor |
| Ceramic capacitor compatible | Stable with 1µF input and 1µF output ceramic capacitors - reduces BOM count and board area vs. tantalum-based LDOs |
| Thermal protection with hysteresis | +165°C shutdown with +30°C hysteresis prevents thermal cycling and ensures safe recovery after overload conditions |
Applications
| Wireless Sensor Node | USB-Powered Peripheral |
|---|---|
|
Use Scenario: Battery-operated temperature/humidity sensor transmitting via BLE or Zigbee. IC Role / Device Role / Timing Role: Primary 1.2V supply for MCU core and RF transceiver IC. Use Value: 60µA quiescent current extends 2xAA battery life to >2 years; 60µVrms noise prevents RF desense during transmission. |
Use Scenario: USB audio interface with DAC, op-amps, and microcontroller. IC Role / Device Role / Timing Role: Clean 1.2V rail for analog signal chain and digital logic. Use Value: 65dB PSRR at 1kHz rejects USB switcher ripple; ±2% accuracy ensures consistent DAC reference compliance. |
| Industrial PLC I/O Module | Wearable Health Monitor |
|
Use Scenario: Isolated analog input channel with precision ADC and signal conditioning. IC Role / Device Role / Timing Role: Local 1.2V supply for ADC reference buffer and PGA. Use Value: Low 1.5%/A load regulation maintains reference stability across varying sensor excitation currents. |
Use Scenario: Compact ECG/PPG module powered by coin cell or small Li-po. IC Role / Device Role / Timing Role: Main power source for ASIC and analog front-end. Use Value: 600mV dropout allows full utilization of 2.0V–3.0V battery range; 0.1µA shutdown current enables multi-year shelf life. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LDO regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MCP1700T-1202E/TT | 250mA max output, 1.8µA quiescent current, no integrated discharge MOSFET | Lacks active VOUT discharge; requires external resistor for fast turn-off | Preferred where ultra-low IQ dominates over discharge requirement and load current ≤250mA |
| Torex XC6206P122MR-G | 300mA output, 1µA IQ, 45dB PSRR @ 1kHz, no thermal shutdown | No thermal protection; lower PSRR limits use in noisy DC/DC-fed systems | Suitable for cost-sensitive, thermally benign environments with minimal ripple coupling risk |
Compared with MCP1700T-1202E/TT and XC6206P122MR-G, AP2129K-1.2TRG1 uniquely combines 300mA capability, 60µVrms noise, active discharge, and thermal shutdown - making it optimal for compact, battery-powered systems requiring both precision and robustness.
Availability
AP2129K-1.2TRG1 is available at Aetrix Electronics and suitable for wireless sensor nodes, USB peripherals, industrial I/O modules, and wearable health monitors requiring stable component supply, long-term lifecycle support, and RoHS/Green compliance.
Supply support for AP2129K-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 manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability power management, signal integrity, and protection solutions for industrial, computing, and consumer markets.
The AP2129 series belongs to Diodes' high-performance LDO portfolio, designed specifically for noise-sensitive, battery-constrained applications demanding ultra-low IQ, fast transient response, and integrated safety features.
FAQ
What is the minimum input voltage required for AP2129K-1.2TRG1 to regulate at full 300mA load?
The AP2129K-1.2TRG1 requires VIN ≥ 1.8V to operate, but to sustain 300mA output at 1.2V with guaranteed dropout margin, VIN must be ≥ 1.8V. Per datasheet Note 2, for 1.2V version, VIN = 2.8V is specified for full-load testing - meaning 1.8V input yields reduced current capability due to headroom constraints. For reliable 300mA delivery, VIN ≥ 1.8V is absolute minimum, though 2.0V+ is recommended.
Can AP2129K-1.2TRG1 be used with tantalum or electrolytic output capacitors?
No - the AP2129K-1.2TRG1 is explicitly characterized and stabilized for use with low-ESR ceramic capacitors (≥1µF). Tantalum or aluminum electrolytic capacitors exhibit higher ESR and capacitance drift, which can cause instability, overshoot, or oscillation. The datasheet mandates ceramic COUT; substituting other types voids performance guarantees and risks regulation failure.
Does the Shutdown pin require a pull-up resistor for normal operation?
No - the Shutdown pin has an internal 3MΩ pull-down resistor, ensuring default-disable state when left floating. A pull-up is only needed if active-high enable is required in systems where the controlling GPIO defaults low. Applying ≥1.5V to Shutdown enables regulation; ≤0.4V disables it and activates the 60Ω discharge path.
Is AP2129K-1.2TRG1 qualified for automotive applications?
No - AP2129K-1.2TRG1 is rated for -40°C to +85°C ambient operation and is not AEC-Q100 qualified. It lacks automotive-specific stress testing, extended temperature validation, and PPAP documentation. For automotive use, Diodes offers the pin-compatible AP7361C-12YG-13 (AEC-Q100 Grade 2), which shares the same 1.2V/300mA specification but with automotive qualification.
AP2129K-1.2TRG1 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):
- 1.2V
- Voltage - Output (Max):
- -
- Voltage Dropout (Max):
- 0.6V @ 300mA (Typ)
- Current - Output:
- 300mA
- Current - Quiescent (Iq):
- 90 µA
- Current - Supply (Max):
- -
- PSRR:
- 65dB ~ 45dB (100Hz ~ 10kHz)
- Control Features:
- Enable
- Protection Features:
- Over Current, Over Temperature, Under Voltage Lockout (UVLO)
- Operating Temperature:
- -40°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-5
AP2129K-1.2TRG1 FAQ
1.How can I place an order for AP2129K-1.2TRG1 through Aetrix?
Please submit a Request for Quotation (RFQ) for AP2129K-1.2TRG1 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 AP2129K-1.2TRG1 reliable?
The price and inventory of AP2129K-1.2TRG1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AP2129K-1.2TRG1 is usually 5 days.
3.What payment methods are accepted for AP2129K-1.2TRG1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AP2129K-1.2TRG1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AP2129K-1.2TRG1?
AP2129K-1.2TRG1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AP2129K-1.2TRG1 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 AP2129K-1.2TRG1?
For technical support, including AP2129K-1.2TRG1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AP2129K-1.2TRG1 requirements.
6.How does Aetrix verify that AP2129K-1.2TRG1 is sourced from the original manufacturer or authorized distributors?
All AP2129K-1.2TRG1 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 AP2129K-1.2TRG1 meets industry standards.
7.What is the process for return or replacement of AP2129K-1.2TRG1?
All AP2129K-1.2TRG1 units undergo pre-shipment inspection (PSI). If there is an issue with AP2129K-1.2TRG1, 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 AP2129K-1.2TRG1 part is unused and in its original packaging.
Return procedure for AP2129K-1.2TRG1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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