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Diodes Incorporated AP2125KS-4.2TRG1
- Part No.:
- AP2125KS-4.2TRG1
- Manufacturer:
- Diodes Incorporated
- Package:
- 5-TSSOP, SC-70-5, SOT-353
- Datasheet:
-
AP2125KS-4.2TRG1.pdf
- Description:
- IC REG LINEAR 4.2V 300MA SC70-5
- Quantity:
- Payment:
- Shipping:
Inventory:2,996
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Product details
Overview
AP2125KS-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 AP2125KS-4.2TRG1 datasheet, AP2125KS-4.2TRG1 pinout, AP2125KS-4.2TRG1 application, or AP2125KS-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 at +160°C.
Technical Context
The AP2125KS-4.2TRG1 integrates a CMOS pass transistor, error amplifier, voltage reference, and over-temperature shutdown (OTSD) circuit. Its architecture delivers stable regulation under fast load transients while maintaining 70dB PSRR at 100Hz and 1kHz for RF-sensitive applications.
It operates across -40°C to +85°C ambient, supports input voltages from (VOUT + 0.5)V up to 6V, and uses an active-high CE pin to enable/disable regulation-allowing system-level power sequencing without external logic.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | Fixed 4.2V ±2% - ensures stable bias for lithium-ion charging circuits and analog sensor front-ends. |
| Max Output Current | 300mA min - sufficient to power baseband processors or RF transceivers in handheld devices. |
| Dropout Voltage | 65mV at 100mA - enables operation with minimal headroom, extending battery runtime in 4.2V nominal systems. |
| RMS Output Noise | 50µVrms (10Hz–100kHz) - critical for low-noise analog signal chains in audio codecs or ADC references. |
| PSRR | 70dB typical at 100Hz/1kHz - suppresses switching noise from adjacent DC-DC converters in mixed-signal PCBs. |
| Quiescent Current | 60µA typical - minimizes idle power loss in always-on subsystems like real-time clocks or wake-up controllers. |
| Standby Current | 0.01µA typical - enables deep-sleep modes with negligible battery drain during extended standby. |
| Thermal Shutdown | +160°C with +25°C hysteresis - protects against sustained overload or poor PCB thermal design without latch-up. |
Pinout & Package
AP2125KS-4.2TRG1 is housed in a 5-pin SC-70-5 package (2.0mm × 2.1mm × 0.9mm), optimized for space-constrained portable designs. Pin assignments are validated per Diodes DS38144 Rev. 2–2.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | VIN | Input supply connection; accepts 4.7V to 6V input for 4.2V output regulation. |
| 2 | GND | Power ground reference; must be low-impedance path to minimize noise coupling. |
| 3 | NC | No internal connection; electrically isolated and may be left unconnected or tied to GND for mechanical stability. |
| 4 | CE | Active-high enable input; logic high (>1.5V) enables regulation, logic low (<0.4V) disables output and reduces current to 0.01µA. |
| 5 | VOUT | Regulated 4.2V output; requires ≥1µF ceramic capacitor with ESR <1Ω for stability. |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low noise regulation | 50µVrms output noise enables clean power for RF receivers and precision ADCs without additional filtering. |
| CMOS-based LDO architecture | Eliminates PNP pass transistor limitations-enables low dropout, fast transient response, and rail-to-rail input compatibility. |
| Enable-controlled shutdown | CE pin reduces total system quiescent current to nanoampere range, supporting multi-week battery shelf life in IoT endpoints. |
| Thermal and current protection | Integrated OTSD and 50mA short-circuit limit prevent damage during fault conditions without external components. |
| Low-ESR capacitor support | Stable with 1µF ceramic output capacitor-reduces BOM count and board area versus tantalum-dependent regulators. |
Applications
| Cellular Baseband Power | Lithium-Ion Charging Bias |
|---|---|
Use Scenario: Powers baseband processor core and memory in CDMA/GSM handsets where RF sensitivity demands ultra-low noise. IC Role / Device Role / Timing Role: Primary 4.2V LDO supplying VDD_CORE of Qualcomm MDM series modems. Use Value: 50µVrms noise prevents bit errors in 256-QAM demodulation; 65mV dropout extends usable battery voltage down to 4.265V. | Use Scenario: Provides precise 4.2V reference for charger IC feedback loop in single-cell Li-ion systems. IC Role / Device Role / Timing Role: Stable voltage source for charger IC's BAT sense node, ensuring accurate termination at 4.20V ±2%. Use Value: ±2% output accuracy directly translates to ±8.4mV charge voltage tolerance-meeting JEITA battery safety limits. |
| Portable Audio Codec Supply | Handheld Instrument Reference Rail |
Use Scenario: Supplies AVDD to stereo audio codecs in Bluetooth headsets and voice recorders. IC Role / Device Role / Timing Role: Low-noise analog rail decoupling DAC/ADC sections from noisy digital supplies. Use Value: 70dB PSRR attenuates 1MHz DC-DC ripple by 100×, reducing audible hiss and THD+N below 0.005%. | Use Scenario: Delivers stable 4.2V reference to 16-bit SAR ADCs and op-amp signal conditioning in handheld DMMs. IC Role / Device Role / Timing Role: Precision voltage source for ADC reference buffer and sensor excitation circuits. Use Value: ±100ppm/°C tempco ensures <±0.35mV drift over -20°C to +70°C operating range-supporting 0.1% measurement accuracy. |
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 | 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 loads | Choose when board space is constrained to 3-pin footprint and full protection is not required. |
| Torex XC6219B422MR-G | 300mA output, 150mV dropout at 100mA, 40µVrms noise, SOT-25 package | Uses active-low CE, lacks short-circuit current limit, higher dropout compromises low-VIN operation | Prefer for ultra-low-noise priority where 4.2V accuracy and thermal safety are secondary. |
Compared with MCP1700T-4202E/TT and XC6219B422MR-G, AP2125KS-4.2TRG1 uniquely combines 65mV dropout, integrated OTSD, and active-high CE in SC-70-5-making it optimal for compact, safety-aware 4.2V Li-ion systems requiring both efficiency and robustness.
Availability
AP2125KS-4.2TRG1 is available at Aetrix Electronics and suitable for cellular handset power management, portable medical sensors, handheld test equipment, and battery-backed real-time clock modules requiring stable component supply and long-term lifecycle assurance.
Supply support for AP2125KS-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 manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability power management, signal integrity, and protection solutions for consumer, industrial, and automotive markets.
The AP2125 series belongs to Diodes' precision LDO portfolio, engineered specifically for noise-sensitive, battery-operated portable electronics where low dropout, ultra-low noise, and enable-controlled power gating are mandatory.
FAQ
What is the minimum input voltage required for AP2125KS-4.2TRG1 to regulate at 4.2V?
The AP2125KS-4.2TRG1 requires VIN ≥ (VOUT + 0.5V) = 4.7V under recommended operating conditions. At 100mA load, its 65mV dropout allows regulation down to 4.265V-but guaranteed regulation starts at 4.7V per datasheet specifications to ensure line/load regulation and PSRR performance across temperature.
Can AP2125KS-4.2TRG1 be used with a 1µF ceramic output capacitor?
Yes-AP2125KS-4.2TRG1 is explicitly designed for stability with ≥1µF ceramic capacitors having ESR <1Ω. The datasheet confirms stable operation using 1µF X5R/X7R MLCCs on both input and output, eliminating need for larger or higher-ESR tantalum capacitors.
Does AP2125KS-4.2TRG1 provide reverse current protection?
No-the AP2125KS-4.2TRG1 does not integrate reverse current blocking. When VIN < VOUT, current can flow backward from VOUT to VIN through the pass device. External protection (e.g., series Schottky diode or ideal diode controller) is required if reverse voltage or backfeed scenarios exist in the system.
How does the CE pin behave during power-up and shutdown sequences?
The CE pin is active-high with 1.5V threshold (VIH) and 0.4V threshold (VIL). During power-up, regulation begins only after CE rises above 1.5V; during shutdown, output disables within 10µs of CE falling below 0.4V, and quiescent current drops to 0.01µA-enabling precise sequencing in multi-rail systems.
AP2125KS-4.2TRG1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- 5-TSSOP, SC-70-5, SOT-353
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- 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:
- Enable
- Protection Features:
- Over Current, Over Temperature
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SC-70-5
AP2125KS-4.2TRG1 FAQ
1.How can I place an order for AP2125KS-4.2TRG1 through Aetrix?
Please submit a Request for Quotation (RFQ) for AP2125KS-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 AP2125KS-4.2TRG1 reliable?
The price and inventory of AP2125KS-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 AP2125KS-4.2TRG1 is usually 5 days.
3.What payment methods are accepted for AP2125KS-4.2TRG1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AP2125KS-4.2TRG1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AP2125KS-4.2TRG1?
AP2125KS-4.2TRG1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AP2125KS-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 AP2125KS-4.2TRG1?
For technical support, including AP2125KS-4.2TRG1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AP2125KS-4.2TRG1 requirements.
6.How does Aetrix verify that AP2125KS-4.2TRG1 is sourced from the original manufacturer or authorized distributors?
All AP2125KS-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 AP2125KS-4.2TRG1 meets industry standards.
7.What is the process for return or replacement of AP2125KS-4.2TRG1?
All AP2125KS-4.2TRG1 units undergo pre-shipment inspection (PSI). If there is an issue with AP2125KS-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 AP2125KS-4.2TRG1 part is unused and in its original packaging.
Return procedure for AP2125KS-4.2TRG1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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