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Texas Instruments TL431AQDBZTG4
- Part No.:
- TL431AQDBZTG4
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
TL431AQDBZTG4.pdf
- Description:
- IC VREF SHUNT ADJ 1% SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:2,048
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Product details
Overview
TL431AQDBZTG4 from Texas Instruments is a precision programmable shunt voltage reference in SOT-23-3 package, delivering 2.495 V nominal reference voltage with ±1% initial tolerance at 25°C, −40°C to +125°C operating range, and 0.2 Ω typical dynamic impedance-used for feedback regulation in isolated DC/DC converters and industrial power supplies.
For engineers reviewing the TL431AQDBZTG4 datasheet, TL431AQDBZTG4 pinout, TL431AQDBZTG4 application, or TL431AQDBZTG4 equivalent, key selection criteria include automotive-grade temperature stability (Q-grade), low output noise, adjustable output (2.5 V to 36 V), and sink-current capability up to 100 mA in compact SOT-23-3 footprint.
Technical Context
The TL431AQDBZTG4 implements a three-terminal adjustable shunt regulator architecture with an internal error amplifier, reference, and output transistor. Its Q-grade rating confirms characterization across −40°C to +125°C, and its 14 mV max reference voltage deviation over that full range ensures stable closed-loop feedback in high-reliability power systems.
Unlike Zener diodes, it provides sharp turn-on characteristics and active output circuitry enabling precise regulation without external compensation in most configurations. The SOT-23-3 pinout (REF–CATHODE–ANODE) supports direct integration into space-constrained feedback networks of flyback and forward converters.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reference Voltage | 2.495 V (nominal); enables accurate 2.5 V–36 V adjustable output via two external resistors |
| Initial Tolerance | ±1% at 25°C (A-grade); guarantees tight setpoint accuracy without calibration |
| Temp Range | −40°C to +125°C (Q-grade); qualified for under-hood automotive and industrial environments |
| Dynamic Impedance | 0.2 Ω typical; maintains stable regulation under fast load transients |
| Sink Current Range | 1 mA to 100 mA; supports wide-range feedback loop current drive |
| Ref Input Current | 2–4 µA typical; minimizes resistor-divider loading error in high-impedance networks |
| Output Noise | Low broadband noise; critical for low-noise analog feedback paths |
Pinout & Package
SOT-23-3 package (2.90 mm × 1.30 mm), surface-mount, lead-free, RoHS-compliant. Pin 1 = REF (input), Pin 2 = CATHODE (output/shunt node), Pin 3 = ANODE (common return).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1 (REF) | Reference input | Threshold comparator input; sets regulation point via external resistor divider |
| Pin 2 (CATHODE) | Shunt output | Current-sinking node tied to primary-side controller feedback; carries full regulation current |
| Pin 3 (ANODE) | Common return | Typically connected to system ground or secondary-side common; defines reference potential |
Key Features
| Feature | Design Value |
|---|---|
| Adjustable output voltage | 2.5 V to 36 V via two external resistors-enables single BOM for multiple output rails |
| Automotive-grade thermal stability | 14 mV max Vref deviation over −40°C to +125°C-ensures consistent regulation in extreme environments |
| Low dynamic impedance | 0.2 Ω typical-reduces output voltage droop during transient load steps |
| Sharp turn-on characteristic | Active output stage eliminates Zener knee uncertainty-improves loop stability and response time |
| Low reference input current | 2–4 µA-permits use of high-value resistor dividers to minimize power loss and thermal drift |
Applications
| Rack Server Power Supply | Industrial AC/DC Converter |
|---|---|
Use Scenario: Primary-side feedback in isolated 48 V–12 V DC/DC modules for telecom/datacenter servers. IC Role / Device Role / Timing Role: Shunt reference providing precise voltage setpoint to optocoupler-coupled PWM controller. Use Value: ±1% initial tolerance and 125°C operation ensure stable output regulation across full thermal envelope and long service life. | Use Scenario: Output voltage regulation in DIN-rail mounted 24 V/48 V industrial power supplies. IC Role / Device Role / Timing Role: Adjustable shunt reference in secondary-side feedback loop with TL431AQDBZTG4 driving optocoupler LED. Use Value: Low 0.2 Ω dynamic impedance maintains tight regulation despite line/load transients and aging effects. |
| AC Inverter Drive | Servo Drive Control Module |
Use Scenario: DC bus voltage monitoring and regulation in motor drive auxiliary power supplies. IC Role / Device Role / Timing Role: Precision reference for isolated sensing and protection circuitry feeding microcontroller ADC inputs. Use Value: Q-grade temperature range ensures reliable operation near heat-generating IGBTs and gate drivers. | Use Scenario: Feedback reference in servo amplifier's isolated auxiliary supply powering position encoder interfaces. IC Role / Device Role / Timing Role: Stable 2.5 V reference source for analog signal conditioning and DAC output scaling. Use Value: Low 2–4 µA reference input current minimizes divider-induced errors in high-resolution feedback paths. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431AIDBZR | A-grade, SOIC-8 package; wider body (4.90 mm × 3.90 mm); higher RθJA (97°C/W) | Better thermal margin in low-airflow PCB layouts; not suitable for ultra-compact designs | Select when board space allows larger footprint and higher power dissipation is needed |
| TL431BQDBZR | B-grade (±0.5%), same SOT-23-3 package and Q-temp rating; tighter initial tolerance | Higher accuracy required for precision feedback loops where calibration is impractical | Select when ±0.5% initial tolerance justifies cost premium over A-grade |
Compared with TL431AQDBZTG4, TL431AIDBZR offers greater thermal mass but requires more PCB area, while TL431BQDBZR delivers tighter 0.5% tolerance in identical SOT-23-3 packaging-making it ideal for high-accuracy, space-constrained industrial feedback designs.
Availability
TL431AQDBZTG4 is available at Aetrix Electronics and suitable for rack server power, industrial AC/DC converters, and servo drive control modules requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for TL431AQDBZTG4 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
Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of leadership in precision reference and power management ICs.
The TL431 product line was designed for high-accuracy, low-drift voltage regulation in isolated power supplies, feedback loops, and safety-critical industrial systems-emphasizing robustness, wide temperature operation, and ease of implementation.
FAQ
What is the reference voltage tolerance of TL431AQDBZTG4 at 25°C?
The TL431AQDBZTG4 has a ±1% initial reference voltage tolerance at 25°C, corresponding to the "A" grade designation. This means its nominal 2.495 V reference falls within 2.470 V to 2.520 V at room temperature, verified per TI's SLVS543S datasheet Section 6.10. This tolerance remains stable across its full −40°C to +125°C operating range.
Does TL431AQDBZTG4 support operation beyond 100°C?
Yes, TL431AQDBZTG4 is rated for continuous operation from −40°C to +125°C (Q-grade). Its electrical characteristics-including reference voltage deviation (max 34 mV), dynamic impedance (0.2 Ω typical), and sink current (1–100 mA)-are fully specified across this full automotive-grade temperature range, making it suitable for under-hood and industrial high-heat environments.
What is the pin configuration of TL431AQDBZTG4?
TL431AQDBZTG4 uses the SOT-23-3 package with top-view pinout: Pin 1 = REF (reference input), Pin 2 = CATHODE (shunt output), Pin 3 = ANODE (common return). This matches the standard TL431 DBZ pinout-not the TL432 variant-and is confirmed in TI's Pin Configuration and Functions section (Figure 5-1, page 4 of SLVS543S).
Can TL431AQDBZTG4 replace a Zener diode in feedback circuits?
Yes, TL431AQDBZTG4 is explicitly designed as a superior replacement for Zener diodes in voltage regulation applications. Its active output stage provides sharper turn-on, lower dynamic impedance (0.2 Ω vs typical Zener >10 Ω), and adjustable output (2.5 V–36 V), enabling higher accuracy and stability in feedback loops of switching power supplies without requiring external compensation.
What is the minimum cathode current required for regulation in TL431AQDBZTG4?
The TL431AQDBZTG4 requires a minimum cathode current of 0.4 mA to maintain regulation, with typical values up to 0.7 mA across temperature (Section 6.10, SLVS543S). This low Imin enables stable operation even in high-resistance feedback networks, reducing power loss and improving efficiency in low-power auxiliary supplies.
TL431AQDBZTG4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Discontinued at Digi-Key
- Reference Type:
- Shunt
- Output Type:
- Adjustable
- Voltage - Output (Min/Fixed):
- 2.495V
- Voltage - Output (Max):
- 36 V
- Current - Output:
- 100 mA
- Tolerance:
- ±1%
- Temperature Coefficient:
- -
- Noise - 0.1Hz to 10Hz:
- -
- Noise - 10Hz to 10kHz:
- -
- Voltage - Input:
- -
- Current - Supply:
- -
- Current - Cathode:
- 700 µA
- Operating Temperature:
- -40°C ~ 125°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
TL431AQDBZTG4 FAQ
1.How can I place an order for TL431AQDBZTG4 through Aetrix?
Please submit a Request for Quotation (RFQ) for TL431AQDBZTG4 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 TL431AQDBZTG4 reliable?
The price and inventory of TL431AQDBZTG4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL431AQDBZTG4 is usually 5 days.
3.What payment methods are accepted for TL431AQDBZTG4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL431AQDBZTG4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TL431AQDBZTG4?
TL431AQDBZTG4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TL431AQDBZTG4 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 TL431AQDBZTG4?
For technical support, including TL431AQDBZTG4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL431AQDBZTG4 requirements.
6.How does Aetrix verify that TL431AQDBZTG4 is sourced from the original manufacturer or authorized distributors?
All TL431AQDBZTG4 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 TL431AQDBZTG4 meets industry standards.
7.What is the process for return or replacement of TL431AQDBZTG4?
All TL431AQDBZTG4 units undergo pre-shipment inspection (PSI). If there is an issue with TL431AQDBZTG4, 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 TL431AQDBZTG4 part is unused and in its original packaging.
Return procedure for TL431AQDBZTG4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TL431AQDBZTG4 Tags
-
TL431AIDBZR
Texas Instruments
-
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
-
AZ431LBNTR-G1
Diodes Incorporated
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LM4040D20IDBZR
Texas Instruments
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LM4041DIM3-ADJ/NOPB
Texas Instruments
-
LM4040DIM3X-2.5/NOPB
Texas Instruments
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LM4040DIM3-2.5/NOPB
Texas Instruments
-
AZ431LANTR-G1
Diodes Incorporated
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