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Diodes Incorporated AP1121ASG-13
- Part No.:
- AP1121ASG-13
- Manufacturer:
- Diodes Incorporated
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
AP1121ASG-13.pdf
- Description:
- IC REG LIN 2.5V/3.3V 1A/1A 8SOP
- Quantity:
- Payment:
- Shipping:
Inventory:1,171
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Product details
Overview
AP1121ASG-13 from Diodes Incorporated is a dual-channel, low-dropout linear regulator IC delivering 1A per channel with fixed outputs of 3.3V (CH1) and 2.5V (CH2), maximum 1.3V dropout at full load, fast transient response, and independent thermal shutdown and current limiting per channel. It targets dual-rail logic supply in PC peripherals and communication equipment operating from up to 18V input.
For engineers reviewing the AP1121ASG-13 datasheet, AP1121ASG-13 pinout, AP1121ASG-13 application, or AP1121ASG-13 equivalent, key selection criteria include verified dual-output voltage accuracy (±2% for VOUT1, ±2% for VOUT2), thermal resistance (θJA = 177°C/W), ripple rejection (60–70 dB at 120 Hz), and SOP-8L package compatibility with standard PCB layout guidelines.
Technical Context
The AP1121ASG-13 integrates two independent LDO regulators sharing ground terminals but featuring separate input and output pins, enabling simultaneous regulation of 3.3V and 2.5V rails without cross-coupling. Each channel employs internal current limiting and thermal shutdown circuitry with dedicated sensing paths.
Its architecture supports stable operation with 10µF output capacitors (ESR 0.15–20Ω) and exhibits 20–33 mV load regulation across 0–1A output range, while maintaining 60–70 dB power supply ripple rejection at 120 Hz - critical for noise-sensitive digital logic interfaces.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage CH1 | 3.300 V ±2% (3.235–3.365 V); ensures compatibility with 3.3V TTL/CMOS logic I/O levels |
| Output Voltage CH2 | 2.500 V ±2% (2.450–2.550 V); matches core voltage requirements of DDR SDRAM and PCI Express I/O |
| Dropout Voltage | 1.3 V max at 1A load; enables regulation from 4.6V input for 3.3V rail and 3.8V input for 2.5V rail |
| Ripple Rejection | 60–70 dB at 120 Hz; suppresses switching noise from upstream DC/DC converters feeding the LDO inputs |
| Thermal Resistance θJA | 177°C/W (SOP-8L, no heatsink); limits junction temperature rise to ≤125°C at 1A/1.3V dropout under natural convection |
| Load Regulation | 26–33 mV (CH1), 20–25 mV (CH2); maintains voltage stability during dynamic current steps in bus termination circuits |
| Current Limit | 1.1 A minimum per channel; provides short-circuit protection without latch-up, supporting safe auto-recovery |
Pinout & Package
SOP-8L (Small Outline Package, 8-lead, 1.27 mm pitch), RoHS-compliant "Green" molding compound, exposed thermal pad not present - thermal management relies on copper area (5.5 mm × 5.5 mm minimum per channel).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (VOUT1) | Channel 1 regulated output | 3.3V rail; requires ≥10 µF capacitor (0.15–20 Ω ESR) to ground for stability |
| 2 (VOUT2) | Channel 2 regulated output | 2.5V rail; same capacitor requirement as VOUT1, independent of CH1 dynamics |
| 3 (VIN1) | Channel 1 input supply | Accepts 4.8–12V input; decoupling capacitor recommended between VIN1 and GND |
| 4 (VIN2) | Channel 2 input supply | Accepts 4–12V input; electrically isolated from VIN1 to prevent crosstalk |
| 5–8 (GND) | Ground terminals | All four pins are internally connected to common ground plane; must be tied to single-point system ground |
Key Features
| Feature | Design Value |
|---|---|
| Dual independent LDO channels | Enables single-package dual-rail supply without external isolation components or sequencing complexity |
| 1.3V max dropout at 1A | Supports high-efficiency linear regulation from wide-input supplies (up to 18V), reducing need for pre-regulation stages |
| Per-channel thermal shutdown | Prevents catastrophic failure during sustained overload or poor PCB thermal design; resets automatically after cooldown |
| 60–70 dB ripple rejection | Preserves signal integrity in mixed-signal systems by attenuating switching noise from upstream SMPS sources |
| Fast transient response | Minimizes output voltage deviation (<±40 mV) during 100 mA → 1 A load steps, critical for burst-mode logic loads |
Applications
| PC Peripheral Power | Communication Interface Supply |
|---|---|
Use Scenario: Providing clean, sequenced 3.3V and 2.5V rails to USB 3.0 controller, PCIe switch, and SATA PHY on add-in cards. IC Role / Device Role / Timing Role: Dual-output LDO regulator supplying core and I/O voltages with independent current limiting and thermal protection. Use Value: Eliminates need for two discrete regulators and associated layout area, while maintaining <±2% output accuracy under dynamic load conditions. |
Use Scenario: Powering RS-485 transceivers and Ethernet PHYs requiring isolated 3.3V logic and 2.5V analog reference rails. IC Role / Device Role / Timing Role: Low-noise dual LDO delivering tightly regulated, ripple-suppressed supplies to interface ICs sensitive to supply-induced jitter. Use Value: Achieves 60–70 dB PSRR at 120 Hz, directly improving signal-to-noise ratio and bit error rate in high-speed serial links. |
| High-Speed Bus Termination | Low-Power Logic Sequencing |
Use Scenario: Supplying termination voltage (VTT) and reference voltage (VREF) for DDR2/DDR3 memory subsystems in embedded controllers. IC Role / Device Role / Timing Role: Precision dual LDO generating matched 3.3V and 2.5V rails with tight load regulation (≤33 mV) across 0–1A range. Use Value: Ensures stable bus impedance matching and reference tracking during memory burst transfers, reducing timing skew. |
Use Scenario: Generating startup-ordered 3.3V and 2.5V supplies for FPGA configuration and I/O banks where sequencing margin is limited. IC Role / Device Role / Timing Role: Independent channel enable not supported, but fast transient response (<10 µs recovery) minimizes voltage droop during power-up transitions. Use Value: Reduces risk of configuration failure due to undershoot on VCCIO during FPGA initialization sequences. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-output LDO regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AP1122ASG-13 | Same SOP-8L package; CH1 = 3.3V, CH2 = 1.8V (not 2.5V); identical dropout (1.3V) and thermal specs | Targets 1.8V-core logic (e.g., LPDDR, ARM Cortex-M cores) instead of 2.5V I/O standards | Select only if system requires 1.8V second rail; not interchangeable for 2.5V-dependent interfaces like PCIe Gen1/2. |
| TSM1022D | SO-8 package; dual 1A LDO with adjustable outputs (via external resistors); higher quiescent current (1.2 mA vs. 0.5 mA typical) | Supports custom voltage combinations but lacks factory-trimmed 3.3V/2.5V accuracy and requires additional BOM components | Choose when flexibility in output voltage is required; avoid if board space or calibration overhead is constrained. |
Compared with AP1121ASG-13, AP1122ASG-13 offers identical form-factor and performance but shifts CH2 to 1.8V, while TSM1022D trades factory-set precision for configurability - making AP1121ASG-13 optimal for fixed 3.3V/2.5V dual-rail systems demanding minimal footprint and guaranteed accuracy.
Availability
AP1121ASG-13 is available at Aetrix Electronics and suitable for PC peripheral power, communication interface supply, and high-speed bus termination requiring stable component supply and long-term production continuity.
Supply support for AP1121ASG-13 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 power management, signal integrity, and protection solutions for industrial, computing, and communications markets.
The AP1121 series belongs to Diodes' precision dual-LDO product line, engineered specifically for noise-sensitive, multi-rail digital systems where space-constrained dual-voltage regulation with guaranteed accuracy and thermal robustness is essential.
FAQ
Is AP1121ASG-13 still in active production?
No - AP1121ASG-13 is marked obsolete per Diodes' DS31011 Rev. 6-4 (October 2021). Aetrix Electronics holds remaining authorized inventory and supports legacy design continuity with full traceability and extended lifecycle coordination, including notification of last-time-buy windows and migration path guidance.
Can AP1121ASG-13 operate with input voltage below 4.8V?
VOUT1 specification (3.3V ±2%) is only guaranteed for VIN1 ≥ 4.8V; operation below this risks dropout and loss of regulation. At VIN1 = 4.6V, the 1.3V dropout limit allows marginal regulation, but output accuracy degrades beyond datasheet limits and thermal stress increases significantly above 125°C junction temperature.
What is the minimum output capacitor ESR requirement?
The AP1121ASG-13 requires output capacitors with ESR between 0.15 Ω and 20 Ω for stability - values outside this range may cause oscillation or excessive overshoot during load transients. Tantalum or low-ESR ceramic capacitors meeting this window are validated in the typical application circuit.
Are the GND pins (5–8) internally connected?
Yes - all four GND pins (pins 5–8) are bonded to a single internal ground plane. They must be connected to the same PCB ground net; splitting or routing them separately introduces ground loop impedance and compromises noise rejection and thermal performance.
AP1121ASG-13 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Output Configuration:
- Positive
- Output Type:
- Fixed
- Number of Regulators:
- 2
- Voltage - Input (Max):
- 18V
- Voltage - Output (Min/Fixed):
- 2.5V, 3.3V
- Voltage - Output (Max):
- -
- Voltage Dropout (Max):
- 1.4V @ 1A, 1.4V @ 1A
- Current - Output:
- 1A, 1A
- Current - Quiescent (Iq):
- 10 mA
- Current - Supply (Max):
- -
- PSRR:
- 60dB (120Hz)
- Control Features:
- -
- Protection Features:
- Over Current, Over Temperature
- Operating Temperature:
- 0°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOP
AP1121ASG-13 FAQ
1.How can I place an order for AP1121ASG-13 through Aetrix?
Please submit a Request for Quotation (RFQ) for AP1121ASG-13 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 AP1121ASG-13 reliable?
The price and inventory of AP1121ASG-13 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AP1121ASG-13 is usually 5 days.
3.What payment methods are accepted for AP1121ASG-13?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AP1121ASG-13 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AP1121ASG-13?
AP1121ASG-13 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AP1121ASG-13 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 AP1121ASG-13?
For technical support, including AP1121ASG-13 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AP1121ASG-13 requirements.
6.How does Aetrix verify that AP1121ASG-13 is sourced from the original manufacturer or authorized distributors?
All AP1121ASG-13 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 AP1121ASG-13 meets industry standards.
7.What is the process for return or replacement of AP1121ASG-13?
All AP1121ASG-13 units undergo pre-shipment inspection (PSI). If there is an issue with AP1121ASG-13, 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 AP1121ASG-13 part is unused and in its original packaging.
Return procedure for AP1121ASG-13:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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