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Texas Instruments TL431QDBVR
- Part No.:
- TL431QDBVR
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- SC-74A, SOT-753
- Datasheet:
-
TL431QDBVR.pdf
- Description:
- IC VREF SHUNT ADJ 2.2% SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:10,656
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Product details
Overview
TL431QDBVR from Texas Instruments is a precision programmable shunt voltage reference in SOT-23-3 package, delivering 2.495 V nominal reference voltage with ±0.5% initial tolerance (B grade), −40°C to +125°C operating range, and 0.2 Ω typical dynamic impedance. It functions as an adjustable feedback element in isolated DC/DC converters, linear regulators, and overvoltage protection circuits.
For engineers reviewing the TL431QDBVR datasheet, TL431QDBVR pinout, TL431QDBVR application, or TL431QDBVR equivalent, key selection criteria include automotive-grade temperature stability, low output noise, sink-current capability up to 100 mA, and compatibility with standard resistor-divider feedback networks for output voltages from 2.5 V to 36 V.
Technical Context
The TL431QDBVR implements a precision bandgap-based error amplifier with internal 2.495 V reference, driving an NPN transistor output stage. Its three-terminal shunt architecture requires external resistors to set output voltage and operates by sinking cathode current proportional to the deviation between REF pin voltage and internal reference.
Designed for automotive applications, the Q-grade variant guarantees operation from −40°C to +125°C with 14 mV max reference voltage drift over temperature and supports stable regulation down to 0.4 mA minimum cathode current. The SOT-23-3 package enables compact placement in space-constrained power supply feedback loops.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reference Voltage | 2.495 V nominal; enables precise feedback setting for output voltages ≥2.5 V using two external resistors |
| Initial Tolerance | ±0.5% at 25°C (B grade); ensures tight output voltage accuracy without trimming in production |
| Temp Range | −40°C to +125°C; qualified for under-hood automotive and industrial high-temp environments |
| Dynamic Impedance | 0.2 Ω typical; provides low AC impedance for stable loop response in switching regulator feedback paths |
| Sink Current Range | 1 mA to 100 mA; supports direct drive of optocoupler LEDs or series-pass transistors in linear regulators |
| Ref Input Current | 2–4 µA typical; minimizes resistor-divider loading error and enables high-value feedback networks |
| Output Noise | Low broadband noise; critical for low-noise LDOs and precision ADC reference buffers |
Pinout & Package
SOT-23-3 package (2.90 mm × 1.30 mm), surface-mount, RoHS-compliant. Pin 1 = Cathode, Pin 2 = Anode, Pin 3 = Reference (REF).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (Pin 1) | Shunt current output node | Connects to regulated output node; sinks current to maintain REF pin at 2.495 V |
| Anode (Pin 2) | Common return path | Typically tied to system ground or negative rail; defines voltage reference point for REF input |
| REF (Pin 3) | Feedback input | High-impedance input sensing divider voltage; regulates when ≈2.495 V relative to Anode |
Key Features
| Feature | Design Value |
|---|---|
| Adjustable Output Voltage | Configurable from 2.5 V to 36 V via external resistor divider - eliminates need for multiple fixed references |
| Automotive Temperature Grade | Qualified for −40°C to +125°C operation - meets AEC-Q100 stress test requirements for automotive power modules |
| Low Dynamic Impedance | 0.2 Ω typical - maintains stable regulation under fast load transients in SMPS feedback loops |
| Sharp Turn-On Characteristic | Fast error amplifier response - enables clean startup and accurate overvoltage clamping in protection circuits |
| Zener Diode Replacement | Superior thermal stability and lower drift vs. discrete Zeners - improves long-term accuracy in battery management systems |
Applications
| AC Inverter Drive Control | Rack Server Power Supply |
|---|---|
Use Scenario: Feedback sensing in isolated flyback or forward converter supplying gate drivers and control logic. IC Role / Device Role / Timing Role: Shunt reference providing precise voltage feedback to PWM controller via optocoupler. Use Value: Enables ±1% output regulation across line/load/temperature with minimal component count and no secondary-side controller. | Use Scenario: Secondary-side voltage monitoring and overvoltage protection in multi-output ATX or EPS12V supplies. IC Role / Device Role / Timing Role: Precision shunt reference triggering crowbar or shutdown circuit upon output overvoltage. Use Value: 0.5% initial tolerance and 14 mV temp drift ensure reliable OVP threshold across full automotive temperature range. |
| Industrial AC/DC Adapter | Servo Drive Power Module |
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 primary-side regulated flyback topology. Use Value: SOT-23-3 footprint allows dense layout; 100 mA sink current drives optocoupler directly without buffer transistor. | Use Scenario: Isolated auxiliary supply regulation for IGBT gate drivers and position encoder interfaces. IC Role / Device Role / Timing Role: Stable reference for isolated DC/DC converter feedback in high-noise motor control environment. Use Value: Low 2.5 µV/√Hz input noise prevents jitter in analog signal conditioning stages downstream of power conversion. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431CDBVR | Commercial grade (0°C to 70°C); 2% initial tolerance (standard grade) or 1% (A grade); same SOT-23-3 package and pinout | Limited to non-automotive industrial or consumer applications where extended temperature range is not required | Select TL431CDBVR only if ambient operating temperature stays within 0°C–70°C and ±1% output accuracy suffices |
| TLVH431QDBVR | Lower 1.24 V reference voltage; 0.5% tolerance; Q-grade (−40°C to +125°C); same SOT-23-3 package but different pin assignment (REF/Anode/Cathode vs Cathode/Anode/REF) | Enables regulation below 2.5 V (e.g., 1.8 V, 3.3 V LDOs); requires PCB layout revision due to reversed pinout | Choose TLVH431QDBVR only when sub-2.5 V output regulation is needed and board redesign is acceptable |
Compared with TL431CDBVR, TL431QDBVR adds automotive temperature qualification and tighter B-grade tolerance; compared with TLVH431QDBVR, it offers higher reference voltage and direct pinout compatibility with legacy TL431 designs, avoiding layout changes.
Availability
TL431QDBVR is available at Aetrix Electronics and suitable for rack server power, industrial AC/DC adapters, and servo drive control modules requiring stable component supply across extended temperature ranges.
Supply support for TL431QDBVR 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, embedded processing, and power management ICs, with decades of expertise in precision reference design.
The TL431 product line delivers cost-effective, high-stability shunt references for feedback, regulation, and protection in power conversion systems targeting automotive, industrial, and computing markets.
FAQ
What is the reference voltage accuracy of TL431QDBVR at 25°C?
The TL431QDBVR has a nominal reference voltage of 2.495 V with ±0.5% initial tolerance at 25°C (B grade), meaning its actual Vref falls between 2.483 V and 2.507 V under standard test conditions. This specification is guaranteed per TI's SLVS543S datasheet Section 6.13 for TL431BQ devices in SOT-23-3 packaging. TL431QDBVR maintains this accuracy across its full −40°C to +125°C operating range with ≤14 mV total drift.
Does TL431QDBVR require external components to function?
Yes, TL431QDBVR requires two external resistors to form a voltage divider from output to REF pin and from REF to Anode, enabling adjustable output voltage from 2.5 V to 36 V. A current-limiting resistor may also be needed on the Cathode path depending on sink current requirements. No capacitors or additional active components are mandatory for basic regulation, though output capacitance is recommended for stability per Figure 6-18 in the datasheet.
Can TL431QDBVR replace a Zener diode in my design?
Yes, TL431QDBVR is explicitly designed as a superior replacement for Zener diodes in voltage regulation and reference applications. Its 0.2 Ω dynamic impedance, sharp turn-on characteristic, and 0.5% initial tolerance outperform most discrete Zeners. Unlike Zeners, TL431QDBVR provides stable performance across −40°C to +125°C and supports adjustable output via resistive feedback - making it ideal for precision power supply feedback loops.
What is the maximum cathode current supported by TL431QDBVR?
TL431QDBVR supports a continuous cathode current range of 1 mA to 100 mA per Absolute Maximum Ratings (Section 6.1) and Recommended Operating Conditions (Section 6.4). At 100 mA, power dissipation must remain within thermal limits - with RθJA = 206°C/W for SOT-23-3, maximum allowable ambient temperature drops to ~75°C at full load. Derating is recommended for sustained high-current operation.
Is TL431QDBVR pin-compatible with other TL431 variants in SOT-23-3?
Yes, TL431QDBVR uses the standard TL431 pinout in SOT-23-3: Pin 1 = Cathode, Pin 2 = Anode, Pin 3 = REF. This matches all TL431x DBZ and DBVR variants (e.g., TL431CDBVR, TL431IDBVR), ensuring drop-in compatibility across temperature grades and tolerances. However, TL432 variants in SOT-23-3 use reversed pinout (Cathode/REF/Anode) and are not pin-compatible.
TL431QDBVR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- SC-74A, SOT-753
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Reference Type:
- Shunt
- Output Type:
- Adjustable
- Voltage - Output (Min/Fixed):
- 2.495V
- Voltage - Output (Max):
- 36 V
- Current - Output:
- 100 mA
- Tolerance:
- ±2.2%
- Temperature Coefficient:
- -
- Noise - 0.1Hz to 10Hz:
- -
- Noise - 10Hz to 10kHz:
- -
- Voltage - Input:
- -
- Current - Supply:
- -
- Current - Cathode:
- 1 mA
- Operating Temperature:
- -40°C ~ 125°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-5
TL431QDBVR FAQ
1.How can I place an order for TL431QDBVR through Aetrix?
Please submit a Request for Quotation (RFQ) for TL431QDBVR 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 TL431QDBVR reliable?
The price and inventory of TL431QDBVR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL431QDBVR is usually 5 days.
3.What payment methods are accepted for TL431QDBVR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL431QDBVR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TL431QDBVR?
TL431QDBVR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TL431QDBVR 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 TL431QDBVR?
For technical support, including TL431QDBVR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL431QDBVR requirements.
6.How does Aetrix verify that TL431QDBVR is sourced from the original manufacturer or authorized distributors?
All TL431QDBVR 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 TL431QDBVR meets industry standards.
7.What is the process for return or replacement of TL431QDBVR?
All TL431QDBVR units undergo pre-shipment inspection (PSI). If there is an issue with TL431QDBVR, 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 TL431QDBVR part is unused and in its original packaging.
Return procedure for TL431QDBVR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TL431QDBVR 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
-
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
-
AZ431LANTR-G1
Diodes Incorporated
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