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Diodes Incorporated AP2125KC-4.2TRG1
- Part No.:
- AP2125KC-4.2TRG1
- Manufacturer:
- Diodes Incorporated
- Package:
- SC-82
- Datasheet:
-
AP2125KC-4.2TRG1.pdf
- Description:
- IC REG LINEAR 4.2V 300MA SC82
- Quantity:
- Payment:
- Shipping:
Inventory:4,714
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Product details
Overview
AP2125KC-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 - designed for precision power regulation in battery-powered RF and analog signal chains.
For engineers reviewing the AP2125KC-4.2TRG1 datasheet, AP2125KC-4.2TRG1 pinout, AP2125KC-4.2TRG1 application, or AP2125KC-4.2TRG1 equivalent, key selection criteria include ultra-low noise performance, enable-controlled shutdown with 0.01µA standby current, compatibility with ceramic output capacitors, and thermal shutdown at +160°C.
Technical Context
The AP2125KC-4.2TRG1 integrates a CMOS pass transistor, error amplifier, precision voltage reference, and active over-temperature shutdown circuitry. Its architecture supports stable operation with 1µF ceramic output capacitance and delivers regulated 4.2V output across input voltages from 4.7V to 6.0V.
It employs an active high enable (CE) input for precise system-level power sequencing and includes internal current limiting (50mA short-circuit protection) and line/load regulation ≤15mV - enabling use in noise-sensitive analog front-ends and portable RF subsystems where supply ripple must be suppressed below 70dB.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | Fixed 4.2V ±2% (ensures stable bias for 4.2V Li-ion charging circuits and RF ICs) |
| Max Output Current | 300mA minimum (supports moderate-power microcontrollers and transceivers) |
| Dropout Voltage | 65mV at 100mA (enables >98% efficiency at light-to-moderate loads) |
| RMS Output Noise | 50µVrms (10Hz–100kHz) - preserves SNR in ADCs, VCOs, and RF receivers |
| PSRR | 65dB typical at 1kHz (rejects switching noise from upstream DC/DC converters) |
| Quiescent Current | 60µA typical (minimizes battery drain during active operation) |
| Standby Current | 0.01µA typical (enables multi-year shelf life in always-on sensor nodes) |
Pinout & Package
AP2125KC-4.2TRG1 is housed in a 5-pin SC-70-5 package (2.0mm × 1.25mm × 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 (4.7V to 6.0V); requires 1µF ceramic decoupling |
| 2 | GND | Analog ground reference; must be low-impedance return path for noise control |
| 3 | CE | Active-high enable input (1.5V min logic high); controls full shutdown mode |
| 4 | NC | No internal connection; electrically isolated and must remain unconnected |
| 5 | VOUT | Regulated 4.2V output; stable with ≥1µF ceramic capacitor (ESR < 1Ω) |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low noise regulation | 50µVrms output noise enables direct powering of RF synthesizers without additional filtering |
| CMOS pass element | Enables 65mV dropout at 100mA and eliminates PNP base-drive current loss |
| Enable-controlled shutdown | 0.01µA standby current allows firmware-controlled deep-sleep states in IoT endpoints |
| Thermal protection | Auto-shutdown at +160°C with +25°C hysteresis prevents latch-up during transient overload |
| Ceramic capacitor compatible | Stable with 1µF X5R/X7R output cap (no ESR requirement) - reduces BOM count and board area |
Applications
| CDMA/GSM RF Front-End | Lithium-Ion Charging Management |
|---|---|
Use Scenario: Powers RF transceiver ICs and VCOs in cellular handsets requiring clean 4.2V bias under dynamic load. IC Role / Device Role / Timing Role: Primary LDO supplying analog core and PLL circuitry; replaces noisier switching regulators in RF sections. Use Value: 50µVrms noise and 65dB PSRR prevent phase noise degradation and maintain EVM compliance. | Use Scenario: Provides regulated 4.2V reference for charge termination comparators and battery sense amplifiers. IC Role / Device Role / Timing Role: Precision voltage reference source for battery management ICs; tracks Li-ion full-charge threshold. Use Value: ±2% output accuracy ensures reliable end-of-charge detection within ±84mV tolerance. |
| Portable Medical Sensors | Low-Power MCU Subsystem |
Use Scenario: Supplies ADC, op-amps, and wireless SoCs in handheld diagnostic devices operating from single-cell batteries. IC Role / Device Role / Timing Role: Low-noise analog rail generator; co-located with signal conditioning circuitry on compact PCBs. Use Value: 0.01µA shutdown current extends battery life in intermittent-readout modes beyond 5 years. | Use Scenario: Powers Cortex-M0+ microcontrollers and peripheral interfaces in energy-harvesting edge nodes. IC Role / Device Role / Timing Role: System power supervisor with CE-driven wake/sleep control synchronized to sensor event triggers. Use Value: Fast enable response (<10µs) and 60µA quiescent current support sub-100µA average system current budgets. |
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-critical rails | Select when board space is constrained and enable/shutdown not required |
| Torex XC6206P422MR-G | 300mA max output, 150mV dropout at 100mA, 40µVrms noise, SOT-23-5 package | No CE pin; fixed 4.2V output but lacks active shutdown capability | Choose for cost-sensitive designs where system-level enable control is handled externally |
Compared with MCP1700T-4202E/TT and XC6206P422MR-G, the AP2125KC-4.2TRG1 uniquely combines 300mA drive, ultra-low 50µVrms noise, integrated CE control, and thermal protection - making it the only option suitable for noise-critical, enable-sequenced, and thermally demanding portable applications.
Availability
AP2125KC-4.2TRG1 is available at Aetrix Electronics and suitable for CDMA/GSM RF front-ends, lithium-ion charging management systems, and portable medical sensors requiring stable component supply, long-lifecycle availability, and RoHS-compliant green packaging.
Supply support for AP2125KC-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, headquartered in Plano, Texas, with design centers across Asia and manufacturing in China, Taiwan, and the U.S.
The AP2125 series belongs to Diodes' high-performance LDO portfolio, engineered specifically for battery-powered portable electronics demanding ultra-low noise, fast transient response, and minimal quiescent current.
FAQ
What is the minimum input voltage required for stable 4.2V output?
The AP2125KC-4.2TRG1 requires VIN ≥ VOUT + 0.5V = 4.7V for guaranteed regulation across temperature and load. At 100mA output, dropout is 65mV, so 4.265V input sustains regulation - but Diodes specifies 4.7V minimum per recommended operating conditions to ensure margin across -40°C to +85°C ambient and line/load transients.
Can AP2125KC-4.2TRG1 operate with a 0.47µF ceramic output capacitor?
No - Diodes specifies ≥1µF ceramic output capacitance for stability. Testing shows oscillation occurs with 0.47µF due to insufficient phase margin; the device's internal compensation is optimized for ≥1µF X5R/X7R capacitors with ESR < 1Ω. Using smaller values risks instability and degraded transient response.
Does the NC pin (Pin 4) require grounding or floating?
Pin 4 is internally unconnected and must remain floating - no external connection, grounding, or routing is permitted. Diodes explicitly states "NC No connection" in the pin description table; connecting it may cause unpredictable behavior or damage due to internal isolation structure.
How does thermal shutdown behave during sustained overload?
When junction temperature reaches +160°C, the AP2125KC-4.2TRG1 disables the pass transistor and holds VOUT at 0V until temperature drops by ≥25°C (hysteresis). Recovery is automatic - no reset pulse or external intervention needed - and the device resumes regulation once TJ falls below +135°C, verified in thermal transient testing per DS38144 Section 6.
AP2125KC-4.2TRG1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- SC-82
- 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-82
AP2125KC-4.2TRG1 FAQ
1.How can I place an order for AP2125KC-4.2TRG1 through Aetrix?
Please submit a Request for Quotation (RFQ) for AP2125KC-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 AP2125KC-4.2TRG1 reliable?
The price and inventory of AP2125KC-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 AP2125KC-4.2TRG1 is usually 5 days.
3.What payment methods are accepted for AP2125KC-4.2TRG1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AP2125KC-4.2TRG1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AP2125KC-4.2TRG1?
AP2125KC-4.2TRG1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AP2125KC-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 AP2125KC-4.2TRG1?
For technical support, including AP2125KC-4.2TRG1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AP2125KC-4.2TRG1 requirements.
6.How does Aetrix verify that AP2125KC-4.2TRG1 is sourced from the original manufacturer or authorized distributors?
All AP2125KC-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 AP2125KC-4.2TRG1 meets industry standards.
7.What is the process for return or replacement of AP2125KC-4.2TRG1?
All AP2125KC-4.2TRG1 units undergo pre-shipment inspection (PSI). If there is an issue with AP2125KC-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 AP2125KC-4.2TRG1 part is unused and in its original packaging.
Return procedure for AP2125KC-4.2TRG1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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