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Diodes Incorporated AP2125KS-1.8TRG1
- Part No.:
- AP2125KS-1.8TRG1
- Manufacturer:
- Diodes Incorporated
- Package:
- 5-TSSOP, SC-70-5, SOT-353
- Datasheet:
-
AP2125KS-1.8TRG1.pdf
- Description:
- IC REG LINEAR 1.8V 300MA SC70-5
- Quantity:
- Payment:
- Shipping:
Inventory:2,006
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Product details
Overview
AP2125KS-1.8TRG1 from Diodes Incorporated is a 300mA, fixed-output 1.8V CMOS low-dropout (LDO) regulator in SC-70-5 package, featuring 50µVrms output noise, 70dB PSRR at 100Hz/1kHz, ±2% output voltage accuracy, and 60µA typical quiescent current-designed for powering noise-sensitive analog circuitry in battery-powered portable electronics.
For engineers reviewing the AP2125KS-1.8TRG1 datasheet, AP2125KS-1.8TRG1 pinout, AP2125KS-1.8TRG1 application, or AP2125KS-1.8TRG1 equivalent, key selection criteria include ultra-low noise performance, high PSRR under light-to-moderate load, thermal shutdown with +160°C trip point, enable-controlled shutdown with 0.01µA standby current, and compatibility with low-ESR ceramic capacitors without external compensation.
Technical Context
The AP2125KS-1.8TRG1 integrates a CMOS pass transistor, precision voltage reference, error amplifier, resistor network for fixed 1.8V output, active-high enable (CE) logic interface, overcurrent protection, and thermal shutdown circuitry. Its architecture delivers stable regulation across input voltages from 2.3V to 6V while maintaining low dropout (10mV at 10mA, 100mV at 100mA).
It operates across –40°C to +85°C ambient, supports fast transient response to load steps (10–100mA), achieves ±100ppm/°C temperature coefficient, and requires only 1µF input and output ceramic capacitors-eliminating need for tantalum or electrolytic types.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | Fixed 1.8V ±2% (1.764–1.836V), enabling direct supply to 1.8V-core logic and RF ICs without external feedback. |
| Max Output Current | 300mA minimum, sufficient for powering microcontrollers, sensors, and baseband processors in handheld devices. |
| Dropout Voltage | 10mV @ 10mA / 100mV @ 100mA, allowing operation with minimal headroom (e.g., 2.8V input → 1.8V output). |
| RMS Output Noise | 50µVrms (10Hz–100kHz), critical for preserving SNR in ADCs, audio codecs, and PLL power rails. |
| PSRR | 70dB typical at 100Hz/1kHz, suppressing switching noise from upstream DC/DC converters. |
| Quiescent Current | 60µA typical, minimizing battery drain during active operation in always-on subsystems. |
| Standby Current | 0.01µA typical when CE = low, enabling µA-level shutdown for extended battery life. |
| Thermal Shutdown | Activates at +160°C with +25°C hysteresis, protecting against sustained overload or poor PCB thermal design. |
Pinout & Package
AP2125KS-1.8TRG1 uses the SC-70-5 surface-mount package (1.25mm × 1.65mm × 0.95mm), optimized for space-constrained portable designs. Pinout is identical to SOT-23-5 but with smaller footprint and thermal resistance of 300°C/W (θJA).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | VIN | Main input supply pin; accepts 2.3V–6V; requires 1µF ceramic decoupling close to pin. |
| 2 | GND | Analog ground reference; must be connected to low-impedance PCB ground plane for noise control. |
| 3 | NC | No internal connection; left unconnected per datasheet-no routing or grounding required. |
| 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 1.8V output; requires 1µF ceramic capacitor with ESR < 1Ω for stability across 1–300mA load range. |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low noise regulation | 50µVrms output noise enables clean power for RF transceivers and high-resolution ADCs without post-LDO filtering. |
| High PSRR at audio frequencies | 70dB rejection at 100Hz/1kHz suppresses ripple from buck converters operating near audio band, preventing audible artifacts. |
| Sub-µA shutdown mode | 0.01µA standby current allows multi-year battery life in IoT sensor nodes with periodic wake-up cycles. |
| Low-ESR capacitor compatibility | Stable with 1µF ceramic capacitors (no ESR requirement), reducing BOM count and PCB area vs. legacy LDOs needing tantalum. |
| Thermal fault protection | +160°C shutdown with +25°C hysteresis prevents latch-up during short-circuit events or thermal runaway in sealed enclosures. |
| Precision output accuracy | ±2% tolerance ensures reliable operation of 1.8V I/O interfaces and core supplies without margining overhead. |
Applications
| CDMA/GSM Handset RF Front-End | Laptop Core Voltage Rail |
|---|---|
Use Scenario: Powers low-noise amplifier (LNA) and mixer stages in cellular handset transceivers. IC Role / Device Role / Timing Role: Ultra-low-noise 1.8V bias supply; replaces noisier switching regulators to preserve receiver sensitivity. Use Value: 50µVrms noise and 70dB PSRR prevent reciprocal mixing and adjacent-channel interference, improving Rx dynamic range by ≥3dB. | Use Scenario: Supplies 1.8V I/O domain for embedded controller or touchpad interface in ultrabook designs. IC Role / Device Role / Timing Role: Secondary LDO delivering regulated 1.8V from main 3.3V rail; enabled via system PMIC control signal. Use Value: 0.01µA shutdown current extends battery runtime during sleep states; SC-70-5 footprint saves space on dense motherboard layouts. |
| Portable Medical Sensor Node | PCMCIA Card Power Management |
Use Scenario: Provides clean 1.8V supply to analog front-end (AFE) and 16-bit sigma-delta ADC in wearable ECG monitor. IC Role / Device Role / Timing Role: Precision, low-drift LDO ensuring ADC reference stability and minimizing offset drift over temperature. Use Value: ±2% output accuracy and ±100ppm/°C tempco maintain <0.1% gain error across –20°C to +70°C operating range. | Use Scenario: Generates 1.8V auxiliary supply for smart card interface logic in PCMCIA expansion cards. IC Role / Device Role / Timing Role: Enable-controlled LDO activated only when card is inserted and enumerated by host controller. Use Value: CE pin allows hot-plug power sequencing; 300mA rating supports burst-mode data transfers without dropout. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LDO regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MCP1700T-1802E/TT | 250mA max output, 1.8V ±2%, 60µA IQ, but only 55dB PSRR at 1kHz and 75µVrms noise. | Lacks thermal shutdown; not rated for continuous 300mA loads above 60°C ambient. | Prefer for cost-sensitive, lower-current applications where PSRR >65dB is not required. |
| TPS7A0518PDBVR | 200mA max output, 1.8V ±1%, 25µA IQ, 30µVrms noise, but requires 2.2µF minimum COUT and has 150mV dropout @100mA. | Superior noise and IQ, but lower current capability and higher dropout limit use with weak input sources. | Choose when ultra-low IQ and noise dominate over current capacity and dropout constraints. |
Compared with MCP1700T-1802E/TT, AP2125KS-1.8TRG1 delivers 15dB higher PSRR and 25µVrms lower noise for RF/analog integrity; versus TPS7A0518PDBVR, it supports 50% higher load current and 50mV lower dropout at 100mA-critical for compact battery-powered systems with tight voltage margins.
Availability
AP2125KS-1.8TRG1 is available at Aetrix Electronics and suitable for CDMA/GSM handsets, portable medical sensors, laptop I/O rails, and PCMCIA card power management requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant green packaging.
Supply support for AP2125KS-1.8TRG1 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-performance power management, signal integrity, and protection solutions for consumer, industrial, and automotive markets.
The AP2125 series belongs to Diodes' ultra-low-noise LDO product line, engineered specifically for battery-powered portable electronics where PSRR, output noise, and standby current directly impact system-level battery life and signal fidelity.
FAQ
What is the minimum input voltage required for AP2125KS-1.8TRG1 to regulate 1.8V output?
The AP2125KS-1.8TRG1 requires VIN ≥ VOUT + VDROP. At 100mA load, dropout is 100mV (typical), so minimum input is 1.9V. Absolute minimum specified VIN is 2.3V per recommended operating conditions-ensuring stable regulation across temperature and process variation.
Can AP2125KS-1.8TRG1 be used with a 0.47µF output capacitor?
No. The datasheet specifies 1µF minimum ceramic output capacitance for stability across 1–300mA load range. Using 0.47µF risks oscillation or degraded transient response, especially at higher currents or elevated temperatures. Always use ≥1µF X5R/X7R ceramic with ≤1Ω ESR.
Does the NC pin (Pin 3) require any PCB layout treatment?
No. Pin 3 is internally unconnected and must remain floating-no solder mask opening, trace, or thermal pad is needed. Routing traces or applying solder paste to this pin may cause mechanical stress or unintended coupling; leave it unconnected and unmasked per Diodes' assembly guidelines.
How does thermal shutdown behave during sustained overload?
When junction temperature reaches +160°C, the AP2125KS-1.8TRG1 shuts down output and draws only standby current. It remains off until temperature falls by ≥25°C (hysteresis), then automatically resumes regulation. This cycle prevents permanent damage but causes intermittent output-designers must size input voltage and PCB copper to avoid repeated cycling under worst-case load.
AP2125KS-1.8TRG1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- 5-TSSOP, SC-70-5, SOT-353
- 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):
- 1.8V
- Voltage - Output (Max):
- -
- Voltage Dropout (Max):
- 0.36V @ 300mA
- Current - Output:
- 300mA
- Current - Quiescent (Iq):
- 90 µA
- Current - Supply (Max):
- -
- PSRR:
- 70db (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-1.8TRG1 FAQ
1.How can I place an order for AP2125KS-1.8TRG1 through Aetrix?
Please submit a Request for Quotation (RFQ) for AP2125KS-1.8TRG1 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-1.8TRG1 reliable?
The price and inventory of AP2125KS-1.8TRG1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AP2125KS-1.8TRG1 is usually 5 days.
3.What payment methods are accepted for AP2125KS-1.8TRG1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AP2125KS-1.8TRG1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AP2125KS-1.8TRG1?
AP2125KS-1.8TRG1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AP2125KS-1.8TRG1 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-1.8TRG1?
For technical support, including AP2125KS-1.8TRG1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AP2125KS-1.8TRG1 requirements.
6.How does Aetrix verify that AP2125KS-1.8TRG1 is sourced from the original manufacturer or authorized distributors?
All AP2125KS-1.8TRG1 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-1.8TRG1 meets industry standards.
7.What is the process for return or replacement of AP2125KS-1.8TRG1?
All AP2125KS-1.8TRG1 units undergo pre-shipment inspection (PSI). If there is an issue with AP2125KS-1.8TRG1, 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-1.8TRG1 part is unused and in its original packaging.
Return procedure for AP2125KS-1.8TRG1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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