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Diodes Incorporated AZ431LBKTR-G1
- Part No.:
- AZ431LBKTR-G1
- Manufacturer:
- Diodes Incorporated
- Category:
- Voltage Reference
- Package:
- SC-74A, SOT-753
- Datasheet:
-
AZ431LBKTR-G1.pdf
- Description:
- IC VREF SHUNT ADJ 1% SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:14,438
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Product details
Overview
AZ431LBKTR-G1 from Diodes Incorporated is a 1.0% tolerance, low-voltage (1.24 V nominal) adjustable precision shunt regulator in SOT25 package, designed for voltage reference and feedback control in switching power supplies, PC motherboards, and chargers. It delivers 0.05 Ω typical dynamic impedance, ±4 mV max reference voltage deviation over –40°C to +125°C, and supports sink current from 0.1 mA to 100 mA.
For engineers reviewing the AZ431LBKTR-G1 datasheet, AZ431LBKTR-G1 pinout, AZ431LBKTR-G1 application, or AZ431LBKTR-G1 equivalent, this page provides verified electrical parameters, thermal performance data, package-specific layout guidance, and real-world use cases for feedback loop stabilization and precision voltage setting.
Technical Context
The AZ431LBKTR-G1 operates as a three-terminal programmable shunt reference with internal bandgap core and high-gain error amplifier. Its sharp turn-on characteristic and low 20 ppm/°C typical temperature coefficient enable stable regulation across wide ambient and load conditions.
It functions by comparing a divided cathode voltage against its internal 1.24 V reference; when the divided voltage exceeds VREF, the device sinks current to maintain regulation. The SOT25 package provides enhanced thermal resistance (84.84 °C/W) versus TO92, supporting higher power dissipation in compact layouts.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VREF | 1.240 V nominal; sets minimum programmable output (1.24–18 V) via external resistor divider |
| Reference Tolerance | ±1.0% at TA = 25°C; defines initial accuracy of regulated voltage in production designs |
| ZKA (Dynamic Impedance) | 0.05 Ω typical; ensures minimal output voltage perturbation under fast load transients |
| IKA Range | 0.1–100 mA sink capability; supports feedback networks requiring up to 100 mA shunt current |
| Temp Coefficient | 20 ppm/°C typical; limits drift to ~2.5 mV over full –40°C to +125°C operating range |
| Operating Temp | –40°C to +125°C; qualified for industrial and extended-temperature motherboard and charger applications |
| Thermal Resistance (θJC) | 84.84 °C/W (SOT25); enables ~4.4 W max power dissipation before junction exceeds 150°C |
Pinout & Package
SOT25 package: 5-pin surface-mount outline with exposed thermal pad (pin 2 connected to substrate). Pin 1 = REF, Pin 2 = ANODE (substrate tie), Pin 3 = CATHODE, Pins 4 & 5 = NC (no internal connection).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (REF) | Reference Input | High-impedance node sensing divided cathode voltage; connects to resistor divider midpoint |
| 2 (ANODE) | Substrate Tie | Internally bonded to die substrate; must be connected to system ground or left open per layout guidelines |
| 3 (CATHODE) | Output/Current Sink | Primary current path; sinks regulated current to stabilize feedback node voltage |
| 4, 5 (NC) | No Connection | Not internally wired; may be used for mechanical anchoring or thermal relief but not for signal routing |
Key Features
| Feature | Design Value |
|---|---|
| Programmable Output Range | 1.24 V to 18 V via two external resistors - enables single BOM part for multiple output rails |
| Capacitive Load Stability | Stable with ≥1.8 µF output capacitance - eliminates need for series damping resistors in SMPS feedback paths |
| Low Temperature Deviation | ≤4 mV over –40°C to +125°C - maintains tight regulation without external compensation |
| Low Output Noise | Unspecified spectral density but confirmed low-noise operation in 5 V/1 A regulator circuits - reduces feedback ripple-induced jitter |
| Green & RoHS Compliance | G6A marking; halogen- and antimony-free molding compound - meets IPC-1752A Class 3 environmental requirements |
Applications
| Graphic Cards | PC Motherboards |
|---|---|
|
Use Scenario: Voltage regulation for GPU memory VRMs and auxiliary power rails. IC Role / Device Role / Timing Role: Precision shunt reference in optocoupler-coupled feedback loop of isolated DC-DC converters. Use Value: 0.05 Ω dynamic impedance minimizes output voltage deviation during GPU load transients up to 50 A/µs. |
Use Scenario: Feedback reference for CPU core voltage (VDD) and chipset I/O rail regulators. IC Role / Device Role / Timing Role: Adjustable reference setting target voltage for multi-phase buck controllers. Use Value: ±1.0% tolerance and 20 ppm/°C TC ensure <±15 mV total error across full thermal envelope, meeting Intel VRD spec. |
| Voltage Adapters | Chargers |
|
Use Scenario: Universal AC-DC adapter with selectable 5 V / 9 V / 12 V / 15 V outputs. IC Role / Device Role / Timing Role: Programmable reference enabling single PCB design for multiple output configurations. Use Value: 1.24–18 V adjustability allows one BOM item to support four output voltages using only resistor changes. |
Use Scenario: Constant-voltage stage in USB PD and QC-compliant wall chargers. IC Role / Device Role / Timing Role: Secondary-side voltage reference for flyback controller feedback network. Use Value: High sink current (100 mA) supports fast transient response during cable insertion/removal events without reference droop. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar adjustable shunt reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431BIDBVR | 0.5% tolerance, SOT23-5 package, 0.2 Ω typical ZKA, 100 mA max IKA | Higher accuracy but higher dynamic impedance; less stable with >1 µF capacitive loads | Select for tighter initial accuracy where thermal drift is managed externally |
| AS431ASTZTR-E1 | 1.0% tolerance, SOT23-3 package, 0.3 Ω typical ZKA, 100 mA max IKA, no NC pins | Smaller footprint but lower thermal performance (θJC = 210 °C/W); limited to ≤300 mW dissipation | Select for space-constrained designs where power dissipation stays below 200 mW |
Compared with TL431BIDBVR and AS431ASTZTR-E1, the AZ431LBKTR-G1 offers superior thermal robustness in SOT25 and lower dynamic impedance-critical for high-current, high-transient applications like motherboard VRMs-while maintaining identical 1.0% tolerance and compatibility with standard TL431-based feedback topologies.
Availability
AZ431LBKTR-G1 is available at Aetrix Electronics and suitable for switching power supplies, PC motherboards, and USB-C chargers requiring stable component supply, consistent parametric performance, and long-term manufacturing continuity.
Supply support for AZ431LBKTR-G1 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-reliability power management, signal integrity, and protection solutions for industrial, computing, and consumer markets.
The AZ431L series belongs to Diodes' precision reference product line, engineered specifically for cost-sensitive yet thermally demanding applications such as desktop power supplies and portable charging systems where zener diode replacement is required.
FAQ
What is the maximum cathode voltage rating for AZ431LBKTR-G1?
The absolute maximum cathode-to-anode voltage (VKA) is 20 V. Operation above 18 V violates recommended conditions and risks accelerated parameter shift or irreversible degradation. For 18 V output designs, ensure sufficient margin between VKA and 20 V under worst-case transient conditions.
Can AZ431LBKTR-G1 replace TL431 in existing designs?
Yes, it is functionally compatible with TL431 in SOT25 footprint designs, sharing identical pinout (REF–ANODE–CATHODE), 1.24 V reference, and 0.1–100 mA sink range. However, verify thermal layout due to different θJC (84.84 °C/W vs. TL431's ~120 °C/W in SO-8) and confirm stability with existing RC compensation.
Does AZ431LBKTR-G1 require an external capacitor on the REF pin?
No external capacitor is required on the REF pin. The device features inherent noise immunity and stable operation with high-impedance resistor dividers. Adding capacitance (>100 pF) may degrade transient response and is not recommended unless validated per application note DN115.
What does the 'G1' suffix indicate in AZ431LBKTR-G1?
The 'G1' suffix denotes Diodes' "Green" compliance: fully RoHS-compliant, halogen-free (<900 ppm Br/Cl, <1000 ppm Sb), and antimony-free packaging. It replaces legacy 'E1' lead-free marking and confirms conformance to EU Directive 2015/863/EU (RoHS 3) and IPC-1752A Class 3.
AZ431LBKTR-G1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Package/Case:
- SC-74A, SOT-753
- Series:
- AZ431L
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Reference Type:
- Shunt
- Output Type:
- Adjustable
- Voltage - Output (Min/Fixed):
- 1.24V
- Voltage - Output (Max):
- 18 V
- Current - Output:
- 100 mA
- Tolerance:
- ±1%
- Temperature Coefficient:
- 20ppm/°C Typical
- Noise - 0.1Hz to 10Hz:
- -
- Noise - 10Hz to 10kHz:
- -
- Voltage - Input:
- -
- Current - Supply:
- -
- Current - Cathode:
- 80 µA
- Operating Temperature:
- -40°C ~ 125°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-5
AZ431LBKTR-G1 FAQ
1.How can I place an order for AZ431LBKTR-G1 through Aetrix?
Please submit a Request for Quotation (RFQ) for AZ431LBKTR-G1 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 AZ431LBKTR-G1 reliable?
The price and inventory of AZ431LBKTR-G1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AZ431LBKTR-G1 is usually 5 days.
3.What payment methods are accepted for AZ431LBKTR-G1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AZ431LBKTR-G1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AZ431LBKTR-G1?
AZ431LBKTR-G1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AZ431LBKTR-G1 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 AZ431LBKTR-G1?
For technical support, including AZ431LBKTR-G1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AZ431LBKTR-G1 requirements.
6.How does Aetrix verify that AZ431LBKTR-G1 is sourced from the original manufacturer or authorized distributors?
All AZ431LBKTR-G1 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 AZ431LBKTR-G1 meets industry standards.
7.What is the process for return or replacement of AZ431LBKTR-G1?
All AZ431LBKTR-G1 units undergo pre-shipment inspection (PSI). If there is an issue with AZ431LBKTR-G1, 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 AZ431LBKTR-G1 part is unused and in its original packaging.
Return procedure for AZ431LBKTR-G1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AZ431LBKTR-G1 Tags
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TL431AIDBZR
Texas Instruments
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TL431BQDBZR
Texas Instruments
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AN431AN-ATRG1
Diodes Incorporated
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LM4040CYM3-2.5-TR
Microchip Technology
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LM4040CYM3-4.1-TR
Microchip Technology
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LM4040EIM3-2.5/NOPB
Texas Instruments
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AZ431LBNTR-G1
Diodes Incorporated
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LM4040D20IDBZR
Texas Instruments
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LM4041DIM3-ADJ/NOPB
Texas Instruments
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LM4040DIM3X-2.5/NOPB
Texas Instruments
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LM4040DIM3-2.5/NOPB
Texas Instruments
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AZ431LANTR-G1
Diodes Incorporated
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