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Diodes Incorporated AP2125KC-4.2TRE1
- Part No.:
- AP2125KC-4.2TRE1
- Manufacturer:
- Diodes Incorporated
- Package:
- SC-82
- Datasheet:
-
AP2125KC-4.2TRE1.pdf
- Description:
- IC REG LINEAR 4.2V 300MA SC82
- Quantity:
- Payment:
- Shipping:
Inventory:2,986
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Product details
Overview
AP2125KC-4.2TRE1 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-4.2TRE1 datasheet, AP2125KC-4.2TRE1 pinout, AP2125KC-4.2TRE1 application, or AP2125KC-4.2TRE1 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-4.2TRE1 integrates a CMOS pass transistor, error amplifier, voltage reference, and enable-controlled shutdown logic. Its architecture delivers stable regulation under fast load transients while maintaining 70dB PSRR at 100Hz and 65dB at 1kHz for noise-sensitive analog rails.
It operates across -40°C to +85°C ambient, supports input voltages from (VOUT + 0.5)V up to 6V, and includes over-temperature shutdown with +25°C hysteresis and 50mA short-circuit current limiting - enabling robust operation in compact portable systems without external protection circuitry.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | Fixed 4.2V ±2% - ensures stable bias for lithium-ion charging management and RF front-end ICs requiring tight voltage tolerance. |
| Max Output Current | 300mA minimum - sufficient to power baseband processors, sensor hubs, or dual-band RF transceivers in handheld devices. |
| Dropout Voltage | 65mV at 100mA - enables operation with minimal headroom (e.g., 4.25V input), extending battery runtime in single-cell Li-ion systems. |
| Output Noise | 50µVrms (10Hz–100kHz) - preserves signal integrity in ADC reference supplies and low-noise amplifier (LNA) bias rails. |
| PSRR | 65dB at 1kHz - suppresses switching noise from adjacent DC/DC converters feeding mixed-signal SoCs. |
| Quiescent Current | 60µA typical - minimizes no-load power loss during system sleep modes in always-on sensor nodes. |
| Standby Current | 0.01µA typical - enables microamp-level shutdown state for long-term storage or deep-sleep firmware updates. |
Pinout & Package
AP2125KC-4.2TRE1 is housed in a 5-pin SC-70-5 surface-mount 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 voltage supply | Accepts 4.7V–6V input; requires ≥1µF ceramic input capacitor for stability and transient response. |
| 2 (GND) | Ground reference | Common return path for input, output, and internal circuits; must be low-impedance connection to minimize noise coupling. |
| 3 (NC) | No connection | Internally unconnected; left floating per design - no external tie required or recommended. |
| 4 (CE) | Enable control input | Active-high logic interface (1.5V min high, 0.4V max low); controls LDO on/off state with <1µs response time. |
| 5 (VOUT) | Regulated output | Delivers 4.2V ±2% to load; requires ≥1µF low-ESR ceramic capacitor for loop stability and noise filtering. |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low output noise | 50µVrms (10Hz–100kHz) - eliminates need for post-regulation LC filtering in RF receiver bias paths. |
| High PSRR at audio frequencies | 65dB @ 1kHz - rejects ripple from buck converter switching edges before they modulate sensitive analog stages. |
| Thermal shutdown with hysteresis | +160°C trip with +25°C hysteresis - prevents latch-up during sustained overload while allowing safe recovery after cooling. |
| Ceramic capacitor compatible | Stable with ≥1µF X5R/X7R MLCCs - reduces BOM count and PCB area vs. tantalum-based LDO solutions. |
| Precision output accuracy | ±2% over temperature and line/load - enables direct powering of 4.2V-tolerant USB PHYs or PMIC reference inputs without trimming. |
Applications
| Cellular RF Front-End | Lithium-Ion Charger Bias Rail |
|---|---|
Use Scenario: Powering LNA, mixer, and PA bias circuits in GSM/CDMA handsets where supply noise directly impacts EVM and receive sensitivity. IC Role / Device Role / Timing Role: Primary low-noise voltage source for analog RF subsystems; regulates VBIAS lines independent of main SoC rail. Use Value: 50µVrms noise and 65dB PSRR prevent AM-to-PM distortion and maintain >35dB ACLR in 850MHz transmit bands. |
Use Scenario: Providing precise 4.2V reference to charger IC feedback networks during constant-voltage charge termination. IC Role / Device Role / Timing Role: Accuracy-critical auxiliary regulator supplying charger IC's VREF pin or op-amp bias in linear/switch-mode charger designs. Use Value: ±2% output tolerance ensures ±10mV absolute accuracy at 4.2V, meeting JEITA-compliant charge termination thresholds. |
| Portable Medical Sensor Hub | Low-Power IoT Edge Node |
Use Scenario: Supplying ADC reference voltage and op-amp rails in wearable ECG/PPG modules where baseline drift degrades diagnostic accuracy. IC Role / Device Role / Timing Role: Ultra-low-noise analog supply generator; decouples digital MCU noise from analog signal chain. Use Value: 50µVrms noise contributes <0.01% FS error in 24-bit delta-sigma ADCs measuring sub-mV bio-potentials. |
Use Scenario: Powering BLE/Wi-Fi SoC peripherals (e.g., flash memory, sensors) during active transmit bursts in battery-operated gateways. IC Role / Device Role / Timing Role: Enable-controlled auxiliary LDO activated only during RF transmission to minimize average system current. Use Value: 0.01µA standby current extends 10-year battery life in sealed industrial telemetry nodes using CR2477 cells. |
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 analog rails | Select when board space is constrained and enable/shutdown functionality is unnecessary. |
| Torex XC6206P422MR-G | 300mA max output, 150mV dropout at 100mA, 40µVrms noise, SOT-23-5 package | Higher dropout limits use with Li-ion cells below 4.35V; no CE pin - always-on operation | Choose for cost-sensitive designs where 4.2V accuracy and low noise are critical but enable control is omitted. |
Compared with MCP1700T-4202E/TT and XC6206P422MR-G, AP2125KC-4.2TRE1 uniquely combines enable control, thermal shutdown, and 65mV ultra-low dropout - making it the only option suitable for dynamically powered RF sections in energy-harvested or coin-cell IoT nodes requiring both precision and safety features.
Availability
AP2125KC-4.2TRE1 is available at Aetrix Electronics and suitable for cellular handset RF biasing, lithium-ion charger reference regulation, portable medical sensor powering, and low-power IoT edge node design requiring stable component supply and full RoHS/Green compliance.
Supply support for AP2125KC-4.2TRE1 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 AP2125 series belongs to Diodes' precision LDO portfolio, engineered specifically for battery-powered portable electronics demanding ultra-low noise, high PSRR, and minimal quiescent current - with emphasis on RF and analog subsystem reliability.
FAQ
What is the minimum input voltage required for AP2125KC-4.2TRE1 to regulate at 4.2V?
The AP2125KC-4.2TRE1 requires VIN ≥ (VOUT + 0.5V) = 4.7V for guaranteed regulation across temperature and load, per Recommended Operating Conditions. At 100mA load, its 65mV dropout allows operation down to 4.265V, but 4.7V ensures stability under worst-case line/load regulation and temperature drift.
Can AP2125KC-4.2TRE1 be used with a 2.2µF ceramic output capacitor?
Yes - the device is explicitly characterized and stable with ≥1µF low-ESR ceramic capacitors (X5R/X7R). A 2.2µF capacitor improves transient response and further reduces output impedance above 100kHz, with no risk of oscillation or phase margin degradation.
Does AP2125KC-4.2TRE1 support reverse current blocking?
No - the AP2125KC-4.2TRE1 does not integrate reverse current blocking. When VIN < VOUT, reverse current can flow through the internal pass FET body diode. External reverse-blocking diodes or MOSFETs are required in applications where backfeed must be prevented.
Is the NC pin (Pin 3) required to be grounded or left floating?
Pin 3 is internally unconnected and must be left floating - no external connection (to GND or otherwise) is permitted. Connecting it may cause unpredictable behavior or damage, as confirmed in the DS38144 pin description table and functional block diagram.
AP2125KC-4.2TRE1 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-4.2TRE1 FAQ
1.How can I place an order for AP2125KC-4.2TRE1 through Aetrix?
Please submit a Request for Quotation (RFQ) for AP2125KC-4.2TRE1 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-4.2TRE1 reliable?
The price and inventory of AP2125KC-4.2TRE1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AP2125KC-4.2TRE1 is usually 5 days.
3.What payment methods are accepted for AP2125KC-4.2TRE1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AP2125KC-4.2TRE1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AP2125KC-4.2TRE1?
AP2125KC-4.2TRE1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AP2125KC-4.2TRE1 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-4.2TRE1?
For technical support, including AP2125KC-4.2TRE1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AP2125KC-4.2TRE1 requirements.
6.How does Aetrix verify that AP2125KC-4.2TRE1 is sourced from the original manufacturer or authorized distributors?
All AP2125KC-4.2TRE1 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-4.2TRE1 meets industry standards.
7.What is the process for return or replacement of AP2125KC-4.2TRE1?
All AP2125KC-4.2TRE1 units undergo pre-shipment inspection (PSI). If there is an issue with AP2125KC-4.2TRE1, 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-4.2TRE1 part is unused and in its original packaging.
Return procedure for AP2125KC-4.2TRE1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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