My Inquiry
My Account
Diodes Incorporated AP2121AK-1.5TRE1
- Part No.:
- AP2121AK-1.5TRE1
- Manufacturer:
- Diodes Incorporated
- Package:
- SC-74A, SOT-753
- Datasheet:
-
AP2121AK-1.5TRE1.pdf
- Description:
- IC REG LINEAR 1.5V 200MA SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:4,382
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
AP2121AK-1.5TRE1 from Diodes Incorporated is a high-speed, extremely low-noise 1.5V fixed-output LDO regulator in SOT-23-5 package, delivering up to 200mA output current with 30µVrms noise (10Hz–100kHz), 70dB PSRR at 1kHz, and ±2% output voltage accuracy. It features active-high enable control, 25µA quiescent current, and supports ceramic capacitors as low as 1µF - deployed in RF-sensitive subsystems of portable wireless devices.
For engineers reviewing the AP2121AK-1.5TRE1 datasheet, AP2121AK-1.5TRE1 pinout, AP2121AK-1.5TRE1 application, or AP2121AK-1.5TRE1 equivalent, key selection criteria include dropout voltage at 200mA load (400–600mV), CE input logic thresholds (VCEH ≥ 1.5V, VCEL ≤ 0.25V), thermal resistance (θJA = 250°C/W), and compatibility with 1µF ceramic input/output capacitors.
Technical Context
The AP2121AK-1.5TRE1 integrates a CMOS-based error amplifier, precision voltage reference, and current-limit protection circuitry. Its architecture enables fast line and load transient response while maintaining stability with ultra-low-ESR ceramic capacitors.
It operates across 2.5V to 6V input range with guaranteed performance from –40°C to +85°C ambient. The device implements an active-high chip-enable function with internal 5MΩ pull-down resistor, allowing controlled shutdown with standby current of 0.1µA typical.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | 1.5V ±2% - ensures stable core voltage for 1.5V logic rails and low-power sensors |
| Max Output Current | 200mA continuous - sufficient for powering RF transceivers or microcontroller peripherals |
| Dropout Voltage | 400–600mV at 200mA - enables operation from single-cell Li-ion (3.0V min) or two-cell alkaline |
| RMS Noise | 30µVrms (10Hz–100kHz) - critical for analog signal chains and ADC reference supplies |
| PSRR | 70dB at 1kHz - suppresses switching noise from upstream DC/DC converters |
| Quiescent Current | 25µA typical - extends battery life in always-on sensor nodes |
| Enable Threshold | VCEH ≥ 1.5V, VCEL ≤ 0.25V - compatible with 1.8V/3.3V GPIO without level-shifting |
Pinout & Package
SOT-23-5 package (JEDEC TO-236AB), 5-pin surface-mount with exposed pad (not electrically connected). Pin 1 marked by dot; standard tape-and-reel packaging per EIA-481.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | CE | Active-high enable input - tie high for operation; pulled down internally to GND via 5MΩ resistor |
| 2 | GND | Power ground reference - must be low-impedance connection to minimize noise coupling |
| 3 | VIN | Main input supply - requires ≥1µF ceramic capacitor placed within 2mm of pin |
| 4 | NC | No connection - left floating; not bonded internally |
| 5 | VOUT | Regulated 1.5V output - requires ≥1µF ceramic capacitor with ESR 0.01–100Ω for stability |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low noise output | 30µVrms enables clean power for RF front-ends and precision ADCs without additional filtering |
| Low dropout at full load | 600mV max at 200mA allows use with input voltages as low as 2.1V while sustaining 1.5V output |
| Ceramic capacitor compatibility | Stable with 1µF output capacitance - eliminates need for bulk tantalum or electrolytic capacitors |
| High PSRR across frequency | 70dB at 1kHz and maintained >40dB up to 100kHz - rejects ripple from switching regulators |
| Precision output accuracy | ±2% over temperature and load ensures reliable operation of 1.5V I/O interfaces and memory |
Applications
| Wireless Sensor Node Power | RF Transceiver Bias Supply |
|---|---|
Use Scenario: Ultra-low-power IoT sensor node powered by coin cell or energy harvester. IC Role / Device Role / Timing Role: Primary 1.5V LDO supplying MCU core, BLE radio, and analog sensor interface. Use Value: 25µA quiescent current and 0.1µA shutdown current maximize battery lifetime; 30µVrms noise prevents RF desense during transmission. |
Use Scenario: 2.4GHz BLE/Wi-Fi transceiver module requiring clean local bias. IC Role / Device Role / Timing Role: Dedicated low-noise 1.5V supply for PA driver stage and LNA bias networks. Use Value: 70dB PSRR suppresses switching noise from main system DC/DC; ±2% accuracy maintains consistent gain and linearity. |
| Portable Medical Monitor | Camera Module Core Logic |
Use Scenario: Handheld pulse oximeter with optical sensor and analog front-end. IC Role / Device Role / Timing Role: Low-noise 1.5V rail for photodiode amplifier and ADC reference buffer. Use Value: 30µVrms noise floor preserves SNR in weak-signal detection; ceramic capacitor compatibility reduces board area and cost. |
Use Scenario: Smartphone camera module requiring compact, stable core voltage. IC Role / Device Role / Timing Role: Secondary 1.5V regulator for image signal processor (ISP) I/O and interface logic. Use Value: Fast load transient response prevents voltage droop during burst pixel readout; SOT-23-5 footprint fits tight space constraints. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LDO regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AP7343-15SAG-7 | Successor device: same 1.5V output, 300mA rating, 20µA IQ, 25µVrms noise, improved PSRR (75dB) | Pin-compatible SOT-23-5 drop-in replacement with enhanced thermal performance (θJA = 220°C/W) | Preferred for new designs due to higher current capability and lower noise; supported for long-term supply |
| MCP1700T-1502E/TT | Microchip 1.5V LDO: 250mA, 1.8µA IQ, but higher noise (90µVrms) and lower PSRR (60dB @ 1kHz) | Optimized for ultra-low-IQ battery monitoring, not RF/precision analog; lacks enable pin | Only suitable where lowest possible quiescent current dominates over noise/PSRR requirements |
Compared with AP2121AK-1.5TRE1, AP7343-15SAG-7 offers higher current headroom and better noise/PSRR for next-gen designs, while MCP1700T-1502E/TT trades noise performance for extreme low-power operation in non-RF contexts.
Availability
AP2121AK-1.5TRE1 is available at Aetrix Electronics and suitable for portable medical monitors, wireless sensor nodes, RF transceiver biasing, and camera module core logic requiring stable component supply with known lifecycle status.
Supply support for AP2121AK-1.5TRE1 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 company specializing in discrete, analog, and mixed-signal ICs, with manufacturing certified to IATF 16949 and AEC-Q100/101 standards.
The AP2121 series belongs to Diodes' high-performance LDO portfolio, designed specifically for battery-powered and noise-sensitive applications demanding low dropout, ultra-low noise, and fast transient response.
FAQ
Is AP2121AK-1.5TRE1 recommended for new designs?
No - Diodes Incorporated explicitly states "THE AP2121 IS NOT RECOMMENDED FOR NEW DESIGNS. PLEASE USE THE AP7343." AP7343-15SAG-7 is the designated successor with improved specifications and long-term supply assurance. AP2121AK-1.5TRE1 remains available for legacy design support and existing production ramps.
What is the minimum input voltage required for 1.5V output at 200mA?
Based on the AP2121-1.5 Electrical Characteristics table, dropout voltage is 400–600mV at IOUT = 200mA. Therefore, minimum input voltage is 1.5V + 0.6V = 2.1V. Operation below this risks regulation loss and output collapse, especially at elevated temperatures.
Can AP2121AK-1.5TRE1 be used with 0.47µF output capacitor?
No - the datasheet specifies "minimum output capacitance required for stability should be more than 1µF" with ESR between 0.01Ω and 100Ω. Using 0.47µF violates the stability requirement and may cause oscillation or poor transient response. Ceramic 1µF or larger is mandatory.
Does the NC pin (Pin 4) require PCB routing or grounding?
No - Pin 4 is explicitly defined as "No connection" in the datasheet and is not bonded internally. It must remain unconnected on the PCB; routing traces or applying solder mask over it is acceptable. No electrical or thermal connection is needed or recommended.
AP2121AK-1.5TRE1 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):
- 1.5V
- Voltage - Output (Max):
- -
- Voltage Dropout (Max):
- 0.6V @ 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-1.5TRE1 FAQ
1.How can I place an order for AP2121AK-1.5TRE1 through Aetrix?
Please submit a Request for Quotation (RFQ) for AP2121AK-1.5TRE1 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-1.5TRE1 reliable?
The price and inventory of AP2121AK-1.5TRE1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AP2121AK-1.5TRE1 is usually 5 days.
3.What payment methods are accepted for AP2121AK-1.5TRE1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AP2121AK-1.5TRE1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AP2121AK-1.5TRE1?
AP2121AK-1.5TRE1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AP2121AK-1.5TRE1 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-1.5TRE1?
For technical support, including AP2121AK-1.5TRE1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AP2121AK-1.5TRE1 requirements.
6.How does Aetrix verify that AP2121AK-1.5TRE1 is sourced from the original manufacturer or authorized distributors?
All AP2121AK-1.5TRE1 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-1.5TRE1 meets industry standards.
7.What is the process for return or replacement of AP2121AK-1.5TRE1?
All AP2121AK-1.5TRE1 units undergo pre-shipment inspection (PSI). If there is an issue with AP2121AK-1.5TRE1, 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-1.5TRE1 part is unused and in its original packaging.
Return procedure for AP2121AK-1.5TRE1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AP2121AK-1.5TRE1 Tags
-
MIC5504-1.8YM5-TR
Microchip Technology
-
MIC5504-3.3YM5-TR
Microchip Technology
-
MIC5365-3.0YC5-TR
Microchip Technology
-
MIC5365-1.8YC5-TR
Microchip Technology
-
MIC5365-2.5YC5-TR
Microchip Technology
-
MIC5365-3.3YC5-TR
Microchip Technology
-
MIC5365-3.3YD5-TR
Microchip Technology
-
MIC5317-3.3YM5-TR
Microchip Technology
-
TLV1117LV33DCYR
Texas Instruments
-
MIC5317-3.3YMT-TZ
Microchip Technology
-
MIC5528-3.3YMT-TR
Microchip Technology
-
TLV75801PDRVR
Texas Instruments
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
