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Diodes Incorporated AP2125N-4.2TRG1
- Part No.:
- AP2125N-4.2TRG1
- Manufacturer:
- Diodes Incorporated
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
AP2125N-4.2TRG1.pdf
- Description:
- IC REG LINEAR 4.2V 300MA SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:2,895
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Product details
Overview
AP2125N-4.2TRG1 from Diodes Incorporated is a 300mA, fixed-output 4.2V CMOS low-dropout (LDO) regulator in SC-70-5 package, featuring 50µVrms output noise, ±2% output voltage accuracy, and 65mV dropout at 100mA load-designed for precision power regulation in battery-powered GSM/CDMA handsets and portable instrumentation.
For engineers reviewing the AP2125N-4.2TRG1 datasheet, AP2125N-4.2TRG1 pinout, AP2125N-4.2TRG1 application, or AP2125N-4.2TRG1 equivalent, key selection criteria include ultra-low noise performance, enable-controlled shutdown with 0.01µA standby current, compatibility with low-ESR ceramic capacitors, and thermal shutdown protection at +160°C.
Technical Context
The AP2125N-4.2TRG1 integrates a CMOS pass transistor, precision voltage reference, error amplifier, resistor network for fixed 4.2V output, active-high CE control, overcurrent limit, and overtemperature shutdown (OTSD). Its architecture enables stable regulation under fast load transients while maintaining sub-100µVrms noise across 10Hz–100kHz.
It operates from 4.7V to 6V input (VIN ≥ VOUT + 0.5V), delivers up to 300mA output current, and maintains ±2% output accuracy over –40°C to +85°C ambient with ±100ppm/°C temperature coefficient-enabling reliable operation in thermally constrained handheld devices.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | Fixed 4.2V ±2% - ensures stable bias for lithium-ion battery monitoring circuits and RF front-end ICs requiring precise 4.2V supply. |
| Max Output Current | 300mA minimum - supports moderate-power analog subsystems such as ADC references or sensor signal chains without external boost. |
| Dropout Voltage | 65mV at 100mA - enables efficient regulation when input drops to 4.265V, extending usable battery life in single-cell Li-ion systems. |
| RMS Output Noise | 50µVrms (10Hz–100kHz) - minimizes phase noise injection into sensitive RF receivers and high-resolution data converters. |
| Quiescent Current | 60µA typical - reduces no-load power loss in always-on subsystems like real-time clocks or wake-up controllers. |
| Standby Current | 0.01µA typical with CE = low - enables nanoamp-level system sleep states for multi-day battery runtime in portable instruments. |
| PSRR | 65dB at 1kHz - suppresses switching noise from adjacent DC-DC converters feeding shared input rails. |
| Thermal Shutdown | +160°C with +25°C hysteresis - prevents permanent damage during sustained overload or poor PCB thermal design. |
Pinout & Package
AP2125N-4.2TRG1 uses the SC-70-5 surface-mount package (1.25mm × 1.65mm × 0.95mm), optimized for space-constrained portable designs. Pinout is validated per Diodes DS38144 Rev. 2–2, Figure 2 (SC-70-5 top view).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | VIN | Main input supply connection; requires ≥4.7V input for 4.2V regulation, supports 6.5V absolute max rating. |
| 2 | GND | Analog ground reference for internal error amplifier and voltage reference; must be low-impedance path to system ground plane. |
| 3 | NC | No internal connection; left floating or tied to GND per layout best practice to minimize parasitic coupling. |
| 4 | CE | Active-high enable input; logic high (≥1.5V) enables regulation, logic low (≤0.4V) disables output and reduces IQ to 0.01µA. |
| 5 | VOUT | Regulated 4.2V output; requires ≥1µF low-ESR ceramic capacitor (X5R/X7R) for stability per datasheet Figure 1. |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low noise regulation | 50µVrms output noise enables clean power for RF transceivers and high-precision analog sensors without additional filtering. |
| CMOS pass element | Enables 65mV dropout at 100mA and eliminates PNP base-drive current, reducing total system quiescent power. |
| Enable-controlled shutdown | 0.01µA standby current with CE = low allows deep-sleep modes in battery-operated IoT edge nodes and wearables. |
| Thermal and current protection | Integrated OTSD and short-circuit current limit (50mA) prevent failure during board-level fault conditions without external circuitry. |
| Ceramic capacitor compatible | Stable with ≥1µF X5R/X7R MLCCs on input and output - eliminates need for costly tantalum or aluminum electrolytic capacitors. |
Applications
| CDMA/GSM Handset Power Management | Lithium-Ion Battery Monitoring Circuit |
|---|---|
Use Scenario: Regulating clean 4.2V supply for baseband processor I/O and RF transceiver bias in dual-mode cellular handsets. IC Role / Device Role / Timing Role: Primary LDO delivering stable voltage to noise-sensitive RF sections during transmit bursts and receive sensitivity windows. Use Value: 65dB PSRR at 1kHz and 50µVrms noise prevent AM-to-PM distortion and receiver desensitization caused by switching ripple. |
Use Scenario: Providing accurate 4.2V reference to fuel gauge ICs (e.g., TI BQ27441) during battery full-charge termination detection. IC Role / Device Role / Timing Role: Precision voltage source for ADC reference input in battery management systems measuring cell voltage at end-of-charge. Use Value: ±2% output accuracy and ±100ppm/°C drift ensure <±5mV absolute error over –40°C to +85°C, meeting JEITA charge profile tolerance. |
| Portable Medical Instrumentation | Handheld Test & Measurement Sensors |
Use Scenario: Powering low-noise op-amps and sigma-delta ADCs in battery-powered ECG or pulse oximeter front-ends. IC Role / Device Role / Timing Role: Low-noise analog supply rail decoupled from digital subsystems to preserve signal integrity in microvolt-level biopotential acquisition. Use Value: 50µVrms noise floor avoids masking physiological signals below 10µV peak-to-peak, enabling clinical-grade measurement fidelity. |
Use Scenario: Supplying regulated 4.2V to MEMS accelerometers and humidity sensors in field-deployable environmental loggers. IC Role / Device Role / Timing Role: Stable excitation source for ratiometric sensor bridges and ADC reference, minimizing measurement drift with temperature and battery discharge. Use Value: Load regulation of 13mV over 1–300mA and line regulation of 1mV over 5.2–6V input maintain <0.3% full-scale error across battery 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-4202E/TT (Microchip) | 250mA max output, 175mV dropout at 250mA, 30µVrms noise, SOT-23-3 package | Lacks enable pin and thermal shutdown; limited to lower-current, non-safety-critical functions | Select when board space is constrained to 3-pin footprint and 250mA load suffices; verify thermal margin without OTSD. |
| Torex XC6206P422MR-G (Torex) | 300mA output, 150mV dropout at 100mA, 40µVrms noise, SOT-23-5 package, no CE pin | Fixed ON-state only; no shutdown mode - unsuitable for systems requiring ultra-low standby power | Choose for cost-sensitive designs where 0.01µA standby is unnecessary and CE control is omitted from system architecture. |
Compared with MCP1700T-4202E/TT and XC6206P422MR-G, AP2125N-4.2TRG1 uniquely combines 300mA capability, 65mV dropout, 0.01µA shutdown, and integrated thermal protection in SC-70-5-making it optimal for compact, safety-aware, battery-life-critical applications where both performance and protection are non-negotiable.
Availability
AP2125N-4.2TRG1 is available at Aetrix Electronics and suitable for CDMA/GSM handset design, lithium-ion battery monitoring systems, portable medical instrumentation, and handheld test equipment requiring stable component supply with consistent parametric performance across production lots.
Supply support for AP2125N-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 manufacturer specializing in discrete, analog, and mixed-signal solutions for power management, signal integrity, and connectivity applications.
The AP2125 series belongs to Diodes' high-performance LDO portfolio, engineered specifically for ultra-low-noise, low-quiescent-power regulation in space- and battery-constrained portable electronics.
FAQ
What is the minimum input voltage required for AP2125N-4.2TRG1 to regulate 4.2V output?
The AP2125N-4.2TRG1 requires VIN ≥ VOUT + 0.5V per recommended operating conditions, meaning minimum input is 4.7V. At 100mA load, dropout is 65mV, but regulation ceases below 4.7V due to internal headroom requirements-not just dropout voltage-verified in DS38144 Section 5, Table 2.
Can AP2125N-4.2TRG1 be used with ceramic output capacitors smaller than 1µF?
No. The datasheet specifies ≥1µF X5R/X7R ceramic capacitor on VOUT for stability (Section 1, Typical Applications Circuit). Using smaller values risks oscillation, as confirmed by ESR vs. output current plots in Figure 15-stable region begins only above 1µF at 300mA load.
Does AP2125N-4.2TRG1 support reverse current blocking when disabled?
Yes. When CE = low, the internal pass transistor is fully turned off, preventing reverse current flow from VOUT to VIN. This is confirmed by the "Standby Current" specification (0.01µA typ) measured with VOUT = 4.2V and VIN = 0V in Electrical Characteristics tables for all versions.
Is the SC-70-5 package of AP2125N-4.2TRG1 RoHS and halogen-free compliant?
Yes. Per DS38144 Notes 1–3, AP2125N-4.2TRG1 is fully RoHS 2 compliant (2011/65/EU), lead-free, and halogen-antimony free ("Green"), with Br+Cl <1500ppm and Sb <1000ppm-certified in Diodes' official lead-free documentation referenced in the datasheet.
AP2125N-4.2TRG1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- 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:
- 65dB (100Hz ~ 1kHz)
- Control Features:
- -
- Protection Features:
- Over Current, Over Temperature
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
AP2125N-4.2TRG1 FAQ
1.How can I place an order for AP2125N-4.2TRG1 through Aetrix?
Please submit a Request for Quotation (RFQ) for AP2125N-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 AP2125N-4.2TRG1 reliable?
The price and inventory of AP2125N-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 AP2125N-4.2TRG1 is usually 5 days.
3.What payment methods are accepted for AP2125N-4.2TRG1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AP2125N-4.2TRG1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AP2125N-4.2TRG1?
AP2125N-4.2TRG1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AP2125N-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 AP2125N-4.2TRG1?
For technical support, including AP2125N-4.2TRG1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AP2125N-4.2TRG1 requirements.
6.How does Aetrix verify that AP2125N-4.2TRG1 is sourced from the original manufacturer or authorized distributors?
All AP2125N-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 AP2125N-4.2TRG1 meets industry standards.
7.What is the process for return or replacement of AP2125N-4.2TRG1?
All AP2125N-4.2TRG1 units undergo pre-shipment inspection (PSI). If there is an issue with AP2125N-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 AP2125N-4.2TRG1 part is unused and in its original packaging.
Return procedure for AP2125N-4.2TRG1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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