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Diodes Incorporated AP2121AK-1.2TRE1
- Part No.:
- AP2121AK-1.2TRE1
- Manufacturer:
- Diodes Incorporated
- Package:
- SC-74A, SOT-753
- Datasheet:
-
AP2121AK-1.2TRE1.pdf
- Description:
- IC REG LINEAR 1.2V 200MA SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:1,966
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Product details
Overview
AP2121AK-1.2TRE1 from Diodes Incorporated is a 1.2V fixed-output, high-speed, ultra-low-noise CMOS LDO regulator in SOT-23-5 package, delivering up to 200mA output current with 150mV typical dropout at 100mA, ±2% output voltage accuracy, and 30µVrms integrated noise (10Hz–100kHz). It targets power-sensitive analog and RF circuitry in portable battery-powered systems requiring clean, stable low-voltage bias.
For engineers reviewing the AP2121AK-1.2TRE1 datasheet, AP2121AK-1.2TRE1 pinout, AP2121AK-1.2TRE1 application, or AP2121AK-1.2TRE1 equivalent, key selection criteria include its 70dB PSRR at 1kHz, 0.1µA standby current, compatibility with 1µF ceramic output capacitors, and CE-controlled shutdown functionality-critical for low-power sequencing and noise-sensitive signal chains.
Technical Context
The AP2121AK-1.2TRE1 integrates a precision voltage reference, error amplifier, resistor network for fixed 1.2V output, current-limit protection, and active-high chip-enable logic. Its CMOS process enables low quiescent current (25µA typical) and fast transient response without external compensation.
It operates across 2V to 6V input range with guaranteed performance from –40°C to +85°C ambient, supports stable regulation with 1µF ceramic output capacitors (ESR 0.01Ω–100Ω), and features internal thermal shutdown and short-circuit current limiting (50mA typical).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | 1.2V ±2% - ensures stable core/bias rail for 1.2V logic or analog circuits within tight tolerance |
| Max Output Current | 200mA continuous - sufficient for powering single-core microcontrollers or sensor signal chains |
| Dropout Voltage | 700mV max at 200mA - enables operation from 2V input while maintaining 1.2V output |
| PSRR | 70dB typical at 1kHz - suppresses switching noise from upstream DC/DC converters feeding the LDO |
| Output Noise | 30µVrms (10Hz–100kHz) - minimizes phase noise in RF receivers and jitter in ADC clocking paths |
| Quiescent Current | 25µA typical - preserves battery life in always-on sensor nodes or standby modes |
| Standby Current | 0.1µA typical - enables deep-sleep power states when CE pin is low |
| Line Regulation | 4mV typical - maintains output stability despite ±0.5V input variation from battery discharge |
Pinout & Package
SOT-23-5 package (JEDEC TO-236AB), 5-pin surface-mount, 1.3mm × 2.9mm footprint, 1.45mm height, lead-free and RoHS compliant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 - CE | Chip Enable input | Active-high logic control: drives VOUT on/off; internal 5MΩ pull-down ensures default-off state |
| 2 - VIN | Input voltage supply | Accepts 2V–6V; requires ≥1µF ceramic input capacitor for stability and ripple filtering |
| 3 - GND | Ground reference | Common return path for input, output, and internal circuitry; must be low-impedance |
| 4 - NC | No connection | Internally unconnected; must remain floating-no routing or soldering permitted |
| 5 - VOUT | Regulated output | Delivers 1.2V ±2%; requires ≥1µF ceramic output capacitor (ESR 0.01–100Ω) for loop stability |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low noise output | 30µVrms (10Hz–100kHz) - directly supports low-jitter clock generation and high-SNR audio/RF front-ends |
| High PSRR at 1kHz | 70dB typical - rejects ripple from noisy switchers without additional LC filtering |
| Low dropout at full load | 700mV max at 200mA - extends usable battery voltage range down to ~1.9V before regulation loss |
| CE-controlled shutdown | 0.1µA standby current with CE = low - enables precise power gating in multi-rail systems |
| Ceramic capacitor compatible | Stable with ≥1µF X5R/X7R ceramics (ESR 0.01–100Ω) - eliminates need for costly tantalum or electrolytic caps |
| ±2% output accuracy | Over temperature and load - ensures reliable operation of 1.2V I/O or core supplies without margin overhead |
Applications
| Mobile Phone Baseband Power | Wireless Sensor Node Bias |
|---|---|
|
Use Scenario: Supplies 1.2V core voltage to baseband processor during active call mode and low-power idle states. IC Role / Device Role / Timing Role: Primary low-noise LDO providing regulated 1.2V rail with fast load transient response to handle burst-mode processing. Use Value: 30µVrms noise prevents baseband signal corruption; 0.1µA standby current extends standby time beyond 72 hours on coin cell. |
Use Scenario: Powers ultra-low-power MCU and analog sensor interface in BLE-enabled environmental sensor node. IC Role / Device Role / Timing Role: Enables duty-cycled operation by shutting down peripherals via CE pin between measurement intervals. Use Value: 25µA quiescent current and 0.1µA shutdown minimize average system current; 1µF ceramic compatibility reduces BOM count. |
| Portable Camera Image Sensor Bias | Sub-board Telecom Power |
|
Use Scenario: Delivers clean 1.2V bias to CMOS image sensor analog front-end (AFE) and PLL clock generator. IC Role / Device Role / Timing Role: Low-noise LDO isolating sensitive AFE from digital switching noise on shared PCB plane. Use Value: 70dB PSRR at 1kHz attenuates 1MHz DC/DC switching harmonics; ±2% accuracy ensures consistent pixel response calibration. |
Use Scenario: Provides isolated 1.2V auxiliary rail for FPGA configuration logic or SerDes PHY on telecom line card sub-board. IC Role / Device Role / Timing Role: Secondary LDO decoupling local logic from main 3.3V/5V backplane supply, improving signal integrity. Use Value: Fast line/load transient response prevents brownout during FPGA configuration bursts; SOT-23-5 footprint fits dense board layouts. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LDO regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AP7343-12SAG-7 | Successor device: same 1.2V output, 300mA rating, 250mV dropout at 300mA, 20µVrms noise, SOT-23-5 | Higher current capability and lower noise; qualified for automotive AEC-Q100 Grade 2 | Preferred for new designs requiring extended lifetime support and higher reliability certification |
| MCP1700-1202E/TO | 1.2V, 250mA, 600mV dropout at 250mA, 35µVrms noise, TO-92 package | Through-hole mounting; higher dropout limits usable input range; no enable pin | Only suitable where SOT-23-5 footprint is unavailable and CE control is not required |
Compared with AP2121AK-1.2TRE1, AP7343-12SAG-7 offers lower noise and automotive qualification but shares identical pinout and footprint; MCP1700-1202E/TO provides through-hole option at cost of higher dropout and no enable function-making it a mechanical rather than functional substitute.
Availability
AP2121AK-1.2TRE1 is available at Aetrix Electronics and suitable for mobile phone baseband power, wireless sensor node bias, portable camera image sensor bias, and sub-board telecom power applications requiring stable component supply, long-term obsolescence management, and traceable sourcing.
Supply support for AP2121AK-1.2TRE1 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 semiconductor manufacturer specializing in discrete, analog, and mixed-signal ICs for power management, signal integrity, and connectivity applications.
The AP2121 series belongs to Diodes' high-performance LDO portfolio, designed specifically for battery-powered portable electronics demanding ultra-low noise, low quiescent current, and fast transient response in compact packages.
FAQ
What is the minimum input voltage required for AP2121AK-1.2TRE1 to maintain regulation?
The AP2121AK-1.2TRE1 requires VIN ≥ (VOUT + VDROP). With a maximum dropout of 700mV at 200mA, the minimum input is 1.9V to sustain 1.2V output under full load. At light loads (<10mA), dropout drops to 20mV, allowing operation down to ~1.22V input-though recommended minimum is 2.0V per datasheet operating conditions.
Can AP2121AK-1.2TRE1 be used with ceramic capacitors smaller than 1µF?
No. The datasheet specifies a minimum 1µF ceramic output capacitor (X5R/X7R, ESR 0.01Ω–100Ω) for loop stability. Using smaller values risks oscillation or poor transient response. Input capacitor must also be ≥1µF ceramic; both values are validated for stability across temperature and load.
Is AP2121AK-1.2TRE1 pin-compatible with other AP2121 variants?
Yes-all AP2121 versions (1.2V to 3.3V) share identical SOT-23-5 pinout and package dimensions. Only the internal resistor network differs; no layout change is needed when selecting alternate output voltages, provided input/output capacitor values meet each variant's stability requirements.
Why does the datasheet state "NOT RECOMMENDED FOR NEW DESIGNS"?
Diodes Incorporated has designated AP2121AK-1.2TRE1 as legacy due to introduction of the improved AP7343 series, which offers lower noise (20µVrms), higher current (300mA), AEC-Q100 qualification, and extended lifetime support. AP2121 remains available for existing designs and last-time buys but lacks roadmap extension.
AP2121AK-1.2TRE1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- SC-74A, SOT-753
- 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):
- 1.2V
- Voltage - Output (Max):
- -
- Voltage Dropout (Max):
- 0.9V @ 200mA
- Current - Output:
- 200mA
- Current - Quiescent (Iq):
- 50 µA
- Current - Supply (Max):
- -
- PSRR:
- 70dB (1kHz)
- Control Features:
- Enable
- Protection Features:
- Over Current
- Operating Temperature:
- -40°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-5
AP2121AK-1.2TRE1 FAQ
1.How can I place an order for AP2121AK-1.2TRE1 through Aetrix?
Please submit a Request for Quotation (RFQ) for AP2121AK-1.2TRE1 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 AP2121AK-1.2TRE1 reliable?
The price and inventory of AP2121AK-1.2TRE1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AP2121AK-1.2TRE1 is usually 5 days.
3.What payment methods are accepted for AP2121AK-1.2TRE1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AP2121AK-1.2TRE1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AP2121AK-1.2TRE1?
AP2121AK-1.2TRE1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AP2121AK-1.2TRE1 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 AP2121AK-1.2TRE1?
For technical support, including AP2121AK-1.2TRE1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AP2121AK-1.2TRE1 requirements.
6.How does Aetrix verify that AP2121AK-1.2TRE1 is sourced from the original manufacturer or authorized distributors?
All AP2121AK-1.2TRE1 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 AP2121AK-1.2TRE1 meets industry standards.
7.What is the process for return or replacement of AP2121AK-1.2TRE1?
All AP2121AK-1.2TRE1 units undergo pre-shipment inspection (PSI). If there is an issue with AP2121AK-1.2TRE1, 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 AP2121AK-1.2TRE1 part is unused and in its original packaging.
Return procedure for AP2121AK-1.2TRE1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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