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Texas Instruments TL431BQDBVRG4
- Part No.:
- TL431BQDBVRG4
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- SC-74A, SOT-753
- Datasheet:
-
TL431BQDBVRG4.pdf
- Description:
- IC VREF SHUNT ADJ 0.5% SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:4,218
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Product details
Overview
TL431BQDBVRG4 from Texas Instruments is a precision programmable shunt voltage reference in SOT-23-3 package, featuring 0.5% initial reference voltage tolerance at 25°C, −40°C to +125°C operating temperature range, and 0.2Ω typical dynamic impedance. It delivers stable 2.483–2.507V reference output adjustable up to 36V via external resistors, and is widely used in isolated feedback loops of AC/DC adapters and industrial power supplies.
For engineers reviewing the TL431BQDBVRG4 datasheet, TL431BQDBVRG4 pinout, TL431BQDBVRG4 application, or TL431BQDBVRG4 equivalent, key selection criteria include automotive-grade thermal stability (Q-temp), low 14–34mV reference voltage drift over full temperature range, sink-current capability from 1mA to 100mA, and compatibility with compact SOT-23-3 PCB layouts requiring minimal board area.
Technical Context
The TL431BQDBVRG4 implements a three-terminal adjustable shunt regulator architecture with an internal error amplifier, reference voltage cell, and output transistor. Its sharp turn-on characteristic and active output stage enable Zener diode replacement in closed-loop regulation circuits without external compensation in many cases.
As a Q-grade device, it is fully characterized for −40°C to +125°C operation and exhibits 14–34mV total reference voltage deviation across that range. The SOT-23-3 package supports high-density designs while maintaining thermal resistance (RθJA = 206°C/W) suitable for moderate-power feedback applications.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reference Voltage (25°C) | 2.483–2.507 V - tight 0.5% tolerance enables accurate output regulation in power supply feedback networks |
| Temp Range | −40°C to +125°C - qualified for automotive and industrial under-hood/enclosure environments |
| Dynamic Impedance | 0.2 Ω typical - ensures minimal output voltage shift under load transients in feedback paths |
| Sink Current Range | 1 mA to 100 mA - supports direct drive of optocoupler LEDs or small-signal transistors in isolated topologies |
| Ref Input Current | 2–4 µA - low bias current minimizes resistor-divider loading error in precision voltage setting |
| Ref Voltage Drift | 14–34 mV over full temp range - verified stability eliminates need for external trimming in most applications |
| Max Cathode Voltage | 36 V - allows use in wide-input-range DC-DC converters and high-voltage auxiliary supplies |
Pinout & Package
SOT-23-3 package (2.90 mm × 1.30 mm body size) with gull-wing leads; moisture sensitivity level (MSL) 1 per JEDEC J-STD-020.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| REF (Pin 1) | Reference input | High-impedance threshold node; connects to resistor divider midpoint to set output voltage |
| CATHODE (Pin 2) | Shunt current output | Sinks regulated current into primary-side controller or optocoupler LED; voltage-controlled by REF |
| ANODE (Pin 3) | Common return | Typically tied to system ground or negative rail; serves as reference point for all internal voltages |
Key Features
| Feature | Design Value |
|---|---|
| 0.5% reference accuracy | Enables ±1% output voltage regulation in flyback and forward converters without post-production calibration |
| Automotive Q-temp rating | Guarantees performance across −40°C to +125°C ambient, meeting AEC-Q100 stress test requirements for under-hood use |
| Low 0.2Ω dynamic impedance | Maintains stable reference under fast load steps, reducing feedback loop instability risk in high-bandwidth PSRs |
| 14–34mV max Vref drift | Eliminates need for temperature-compensated resistor networks in cost-sensitive industrial power modules |
| 2–4µA reference input current | Permits use of high-value divider resistors (e.g., 100kΩ–1MΩ), lowering quiescent power in always-on auxiliary supplies |
Applications
| AC/DC Adapter Feedback | Rack Server VRM Monitoring |
|---|---|
Use Scenario: Isolated feedback path in 65W notebook adapter using TL431BQDBVRG4 + PC817 optocoupler to regulate +19.5V output. IC Role / Device Role / Timing Role: Precision shunt reference generating error signal proportional to output deviation; sets optocoupler LED current to adjust PWM duty cycle on primary side. Use Value: 0.5% Vref tolerance and 14–34mV temp drift ensure ±1.2% output regulation across full operating temperature, meeting USB PD spec limits. | Use Scenario: Secondary-side voltage monitoring in 12V/54A server VRM, where TL431BQDBVRG4 compares output against reference and triggers fault latch if >1% overvoltage occurs. IC Role / Device Role / Timing Role: High-accuracy comparator reference enabling precise overvoltage detection independent of controller IC's internal reference. Use Value: Automotive-grade thermal stability guarantees consistent trip threshold from cold start to full-load thermal soak, preventing false shutdowns. |
| Industrial Motor Drive PSU | Automotive Body Control Module |
Use Scenario: Auxiliary 5V supply regulation in VF inverter drive, where TL431BQDBVRG4 sets feedback voltage for UCC28C4x controller in flyback topology. IC Role / Device Role / Timing Role: Programmable shunt reference defining regulated output voltage; sinks current into controller COMP pin to adjust duty cycle. Use Value: SOT-23-3 footprint and 206°C/W RθJA allow integration into space-constrained gate driver PCBs without heatsinking. | Use Scenario: Low-power 3.3V LDO supervision circuit in BCM ECU, where TL431BQDBVRG4 monitors microcontroller supply and asserts reset if voltage drops below 3.15V. IC Role / Device Role / Timing Role: Precision voltage threshold detector; configured as comparator with hysteresis via external resistor network. Use Value: −40°C to +125°C qualification ensures reliable reset assertion during engine bay thermal cycling, meeting ISO 16750-4 requirements. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431BIDBVR | I-grade (−40°C to +85°C), same 0.5% tolerance and SOT-23-3 package | Lacks extended high-temp capability; unsuitable for under-hood or high-ambient industrial enclosures | Select when ambient stays ≤85°C and cost optimization is prioritized over thermal margin |
| TLVH431BQDBVR | Lower 1.24V reference voltage, 0.5% tolerance, Q-temp, but higher 3.5µA ref current and 0.35Ω impedance | Enables lower-voltage feedback designs (e.g., 1.8V rails); less stable under high-frequency transients | Choose for sub-2.5V output regulation where TL431BQDBVRG4's 2.5V minimum is too high |
Compared with TL431BIDBVR, TL431BQDBVRG4 provides guaranteed operation to +125°C and tighter thermal drift control-critical for automotive and industrial reliability. Versus TLVH431BQDBVR, it offers superior dynamic impedance and lower reference current, making it preferred for high-precision 2.5V+ feedback loops.
Availability
TL431BQDBVRG4 is available at Aetrix Electronics and suitable for rack server power, industrial AC/DC, and automotive body control module designs requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for TL431BQDBVRG4 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 delivering analog, embedded processing, and connectivity solutions with emphasis on reliability, longevity, and automotive qualification.
The TL431 product line delivers precision programmable shunt references for feedback, monitoring, and voltage supervision in power conversion systems-designed specifically for high-volume industrial, computing, and automotive applications demanding robust thermal performance and long-term supply stability.
FAQ
What is the reference voltage tolerance of TL431BQDBVRG4 at 25°C?
The TL431BQDBVRG4 has a reference voltage tolerance of ±0.5% at 25°C, corresponding to a 2.483 V to 2.507 V range. This B-grade accuracy is specified in TI's SLVS543S datasheet Section 6.13 and enables high-precision output regulation without post-manufacturing calibration. The TL431BQDBVRG4 maintains this tolerance across its full −40°C to +125°C operating range with verified drift performance.
Does TL431BQDBVRG4 support operation above 85°C?
Yes, TL431BQDBVRG4 is explicitly qualified for continuous operation from −40°C to +125°C (Q-grade). Its electrical characteristics-including reference voltage, dynamic impedance, and sink current-are fully specified across this extended range in Section 6.13 of the TI datasheet. This makes TL431BQDBVRG4 suitable for under-hood automotive applications and high-ambient industrial environments where standard I-grade (−40°C to +85°C) variants would fail.
What is the dynamic impedance of TL431BQDBVRG4 and why does it matter?
The TL431BQDBVRG4 has a typical dynamic impedance of 0.2 Ω, measured at 1 kHz with cathode current from 1 mA to 100 mA. This low value ensures minimal output voltage variation during load transients in feedback loops-critical for maintaining regulation accuracy in switching power supplies. High dynamic impedance would cause excessive error signal distortion and potential loop instability, especially in high-bandwidth PSR designs.
Can TL431BQDBVRG4 replace a Zener diode in my design?
Yes, TL431BQDBVRG4 is engineered as a precision Zener diode replacement. Unlike passive Zeners, it features active regulation with sharp turn-on, low dynamic impedance (0.2 Ω vs. typical Zener's 10–100 Ω), and adjustable output (2.5 V to 36 V). Its 0.5% tolerance and temperature stability eliminate Zener's poor accuracy and drift issues. In practice, TL431BQDBVRG4 improves regulation accuracy by >5× and reduces output ripple in feedback-coupled SMPS designs.
What package type is used for TL431BQDBVRG4 and what are its key mechanical properties?
TL431BQDBVRG4 uses the SOT-23-3 package (body size 2.90 mm × 1.30 mm, nominal). It features gull-wing surface-mount leads, JEDEC-standard footprint, and MSL-1 moisture sensitivity rating-enabling reflow soldering without dry-pack requirements. The package's thermal resistance is RθJA = 206°C/W, supporting dissipation up to ~350 mW at 25°C ambient, sufficient for most optocoupler-driven feedback applications.
TL431BQDBVRG4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- SC-74A, SOT-753
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Reference Type:
- Shunt
- Output Type:
- Adjustable
- Voltage - Output (Min/Fixed):
- 2.495V
- Voltage - Output (Max):
- 36 V
- Current - Output:
- 100 mA
- Tolerance:
- ±0.5%
- 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-23-5
TL431BQDBVRG4 FAQ
1.How can I place an order for TL431BQDBVRG4 through Aetrix?
Please submit a Request for Quotation (RFQ) for TL431BQDBVRG4 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 TL431BQDBVRG4 reliable?
The price and inventory of TL431BQDBVRG4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL431BQDBVRG4 is usually 5 days.
3.What payment methods are accepted for TL431BQDBVRG4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL431BQDBVRG4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TL431BQDBVRG4?
TL431BQDBVRG4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TL431BQDBVRG4 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 TL431BQDBVRG4?
For technical support, including TL431BQDBVRG4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL431BQDBVRG4 requirements.
6.How does Aetrix verify that TL431BQDBVRG4 is sourced from the original manufacturer or authorized distributors?
All TL431BQDBVRG4 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 TL431BQDBVRG4 meets industry standards.
7.What is the process for return or replacement of TL431BQDBVRG4?
All TL431BQDBVRG4 units undergo pre-shipment inspection (PSI). If there is an issue with TL431BQDBVRG4, 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 TL431BQDBVRG4 part is unused and in its original packaging.
Return procedure for TL431BQDBVRG4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TL431BQDBVRG4 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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