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Diodes Incorporated AP2121N-3.3TRG1
- Part No.:
- AP2121N-3.3TRG1
- Manufacturer:
- Diodes Incorporated
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
AP2121N-3.3TRG1.pdf
- Description:
- IC REG LINEAR 3.3V 200MA SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:3,160
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Product details
Overview
AP2121N-3.3TRG1 from Diodes Incorporated is a 3.3V fixed-output, high-speed, ultra-low-noise CMOS LDO regulator in SOT-23-3 package, delivering up to 200mA output current with 150mV typical dropout at 100mA, 30µVrms output noise (10Hz–100kHz), and ±2% output voltage accuracy over -40°C to +85°C - designed for powering noise-sensitive analog circuitry in portable battery-powered systems.
For engineers reviewing the AP2121N-3.3TRG1 datasheet, AP2121N-3.3TRG1 pinout, AP2121N-3.3TRG1 application, or AP2121N-3.3TRG1 equivalent, key selection considerations include its low quiescent current (25µA typ), 70dB PSRR at 1kHz, compatibility with 1µF ceramic output capacitors, and CE-enabled shutdown capability - all critical for space-constrained, low-power, high-PSRR rail generation.
Technical Context
The AP2121N-3.3TRG1 integrates a precision voltage reference, error amplifier, and current-limit protection in a single-stage CMOS architecture optimized for fast transient response and minimal output voltage deviation under load or line changes. Its internal chip-enable circuit enables logic-controlled power gating with 0.1µA standby current.
It operates across 2V to 6V input range while maintaining stable 3.3V output with ≤12mV load regulation and ≤4mV line regulation. The device uses no external compensation and is stable with ceramic capacitors as low as 1µF and ESR between 0.01Ω and 100Ω.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | 3.3V ±2% - ensures reliable biasing of 3.3V logic, ADCs, and RF front-ends without post-regulation trimming |
| Max Output Current | 200mA continuous - sufficient for powering microcontrollers, sensors, and interface ICs in compact portable devices |
| Dropout Voltage | 150mV typ @ 100mA - enables operation from single-cell Li-ion (3.0V min) or two-cell alkaline (3.2V min) with margin |
| Output Noise | 30µVrms (10Hz–100kHz) - preserves SNR in audio codecs, precision ADCs, and RF synthesizer VCO supplies |
| PSRR | 70dB typ @ 1kHz - suppresses switching noise from upstream DC/DC converters feeding the LDO input |
| Quiescent Current | 25µA typ - extends battery life in always-on sensor nodes and low-duty-cycle IoT endpoints |
| Enable Threshold | VCE(HI) ≥1.5V, VCE(LO) ≤0.25V - compatible with 1.8V/3.3V GPIO for clean, low-leakage power sequencing |
Pinout & Package
SOT-23-3 package: 3-pin surface-mount, JEDEC MO-178AA compliant, 1.3mm × 2.9mm footprint, 1.45mm height, thermal resistance θJA = 250°C/W.
| Pin | Circuit Role | Design Meaning |
|---|---|---|
| 1 (VIN) | Input voltage supply | Accepts 2V–6V unregulated input; requires ≥1µF ceramic decoupling capacitor close to pin |
| 2 (GND) | Ground reference | Common return path for input/output currents; must be low-impedance connection to system ground plane |
| 3 (VOUT) | Regulated output | Delivers stable 3.3V; requires ≥1µF ceramic output capacitor with ESR 0.01–100Ω for stability |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low noise regulation | 30µVrms output noise enables direct powering of RF VCOs and high-resolution SAR ADCs without additional filtering |
| High PSRR at audio frequencies | 70dB rejection at 1kHz suppresses ripple from buck converter switching harmonics entering the LDO input rail |
| Low-quiescent-current enable control | 0.1µA standby current during CE = low allows >1-year battery life in wake-on-event sensor applications |
| Ceramic capacitor compatibility | Stable with 1µF output capacitance eliminates need for bulk tantalum or electrolytic capacitors, reducing board area and cost |
| Precision output accuracy | ±2% tolerance over temperature and load ensures timing-critical circuits (e.g., USB PHY, SDIO) meet voltage compliance margins |
Applications
| Mobile Phone Baseband Power | Wireless Audio Codec Supply |
|---|---|
Use Scenario: Powering baseband processor I/O and memory interface rails in slim smartphone designs. IC Role / Device Role / Timing Role: Primary 3.3V LDO supplying core logic and DDR I/O buffers with tight voltage tolerance. Use Value: Low dropout enables operation down to 3.0V battery voltage; 30µVrms noise prevents digital switching noise from corrupting analog baseband signals. |
Use Scenario: Clean power delivery to stereo audio DAC/ADC in Bluetooth earbuds and portable speakers. IC Role / Device Role / Timing Role: Dedicated low-noise analog supply rail decoupled from noisy digital subsystems. Use Value: 70dB PSRR attenuates 1MHz+ switching noise from PMU DC/DC; ±2% accuracy maintains THD+N spec across battery discharge cycle. |
| Industrial Sensor Node MCU Core | Camera Module Image Signal Processor |
Use Scenario: Regulating 3.3V for ARM Cortex-M0+ MCU and sub-GHz RF transceiver in battery-operated environmental monitors. IC Role / Device Role / Timing Role: Always-on LDO with CE-controlled shutdown during deep sleep mode. Use Value: 25µA quiescent current and 0.1µA shutdown current extend 2xAA battery life beyond 2 years in 1-minute sampling intervals. |
Use Scenario: Providing stable 3.3V to CIS image signal processor and MIPI D-PHY interface in compact security cameras. IC Role / Device Role / Timing Role: Low-noise, fast-transient LDO placed adjacent to ISP die for minimal supply-induced jitter. Use Value: Excellent load transient response prevents frame corruption during burst pixel readout; 1µF ceramic compatibility saves PCB real estate. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LDO regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AP7343-33SG-7 | Successor LDO with same 3.3V output, 300mA rating, lower 50mV dropout, and improved 80dB PSRR at 1kHz | Designed for new designs requiring longer product lifecycle support and AEC-Q100 qualification path | Preferred for new designs due to active status, enhanced specs, and automotive qualification readiness |
| MCP1700T-3302E/TT | 3.3V LDO with 250mA rating, 175mV dropout, 60dB PSRR at 1kHz, and 1.6µA quiescent current - but higher noise (40µVrms) | Better suited for ultra-low-IQ applications where noise sensitivity is secondary to battery longevity | Consider only if <2µA quiescent current is mandatory and 10µVrms noise margin can be relaxed |
Compared with AP2121N-3.3TRG1, AP7343-33SG-7 offers superior PSRR and lower dropout for next-gen designs, while MCP1700T-3302E/TT trades noise performance for extreme low-IQ - making AP2121N-3.3TRG1 optimal where 30µVrms noise and 25µA IQ represent the best balance for portable analog-intensive systems.
Availability
AP2121N-3.3TRG1 is available at Aetrix Electronics and suitable for mobile phone baseband power, wireless audio codec supply, industrial sensor node MCU core, and camera module image signal processor applications requiring stable component supply with known legacy design support.
Supply support for AP2121N-3.3TRG1 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 communications markets.
The AP2121 series belongs to Diodes' high-speed, low-noise LDO product line, engineered specifically for battery-powered portable electronics demanding ultra-low noise, fast transient response, and minimal board space.
FAQ
What is the recommended input and output capacitor configuration for AP2121N-3.3TRG1?
A minimum 1µF X5R/X7R ceramic capacitor is required at both input and output. The output capacitor must have ESR between 0.01Ω and 100Ω; typical 1µF/0603 ceramics meet this. Place capacitors within 2mm of respective pins with short, wide traces and solid ground plane beneath.
Does AP2121N-3.3TRG1 require an external enable pull-up resistor?
No external pull-up is required: the CE pin has an internal 5MΩ pull-down resistor (2.5–10MΩ range). When left floating, CE defaults to logic low, disabling the output. To enable, drive CE ≥1.5V from a GPIO or dedicated enable signal - no external components needed.
Can AP2121N-3.3TRG1 operate with input voltage below 3.3V?
Yes - it functions down to VIN = 2.0V. At VIN = 3.0V, dropout is ~150mV, delivering 2.85V output. Full 3.3V regulation requires VIN ≥ 3.45V (3.3V + 150mV). For single-cell Li-ion (2.8–4.2V), it regulates fully above ~3.45V and enters dropout below that threshold.
Is AP2121N-3.3TRG1 qualified for automotive applications?
No - AP2121N-3.3TRG1 is not AEC-Q100 qualified. Diodes recommends contacting their automotive team for AP7343 variants, which support PPAP, IATF 16949 manufacturing, and AEC-Q100 Grade 1 qualification for under-hood and infotainment use cases.
AP2121N-3.3TRG1 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:
- Obsolete
- Output Configuration:
- Positive
- Output Type:
- Fixed
- Number of Regulators:
- 1
- Voltage - Input (Max):
- 6V
- Voltage - Output (Min/Fixed):
- 3.3V
- Voltage - Output (Max):
- -
- Voltage Dropout (Max):
- 0.5V @ 200mA
- Current - Output:
- 200mA
- Current - Quiescent (Iq):
- 50 µA
- Current - Supply (Max):
- -
- PSRR:
- 70dB (1kHz)
- Control Features:
- -
- Protection Features:
- Over Current
- Operating Temperature:
- -40°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
AP2121N-3.3TRG1 FAQ
1.How can I place an order for AP2121N-3.3TRG1 through Aetrix?
Please submit a Request for Quotation (RFQ) for AP2121N-3.3TRG1 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 AP2121N-3.3TRG1 reliable?
The price and inventory of AP2121N-3.3TRG1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AP2121N-3.3TRG1 is usually 5 days.
3.What payment methods are accepted for AP2121N-3.3TRG1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AP2121N-3.3TRG1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AP2121N-3.3TRG1?
AP2121N-3.3TRG1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AP2121N-3.3TRG1 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 AP2121N-3.3TRG1?
For technical support, including AP2121N-3.3TRG1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AP2121N-3.3TRG1 requirements.
6.How does Aetrix verify that AP2121N-3.3TRG1 is sourced from the original manufacturer or authorized distributors?
All AP2121N-3.3TRG1 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 AP2121N-3.3TRG1 meets industry standards.
7.What is the process for return or replacement of AP2121N-3.3TRG1?
All AP2121N-3.3TRG1 units undergo pre-shipment inspection (PSI). If there is an issue with AP2121N-3.3TRG1, 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 AP2121N-3.3TRG1 part is unused and in its original packaging.
Return procedure for AP2121N-3.3TRG1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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