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Texas Instruments TL431BQDBVT
- Part No.:
- TL431BQDBVT
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- SC-74A, SOT-753
- Datasheet:
-
TL431BQDBVT.pdf
- Description:
- IC VREF SHUNT ADJ 0.5% SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:6,371
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Product details
Overview
TL431BQDBVT 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 at 25°C, 14–34 mV total temperature drift over −40°C to +125°C, and 0.2 Ω typical dynamic impedance. It operates as an adjustable feedback element in isolated DC/DC converters and industrial power supplies.
For engineers reviewing the TL431BQDBVT datasheet, TL431BQDBVT pinout, TL431BQDBVT application, or TL431BQDBVT equivalent, key selection criteria include automotive-grade temperature range (−40°C to 125°C), low output noise, sink-current capability up to 100 mA, and compatibility with standard resistor-divider programming for output voltages from 2.5 V to 36 V.
Technical Context
The TL431BQDBVT implements a precision bandgap-based error amplifier with internal reference, configured as a three-terminal shunt regulator. Its REF pin senses voltage relative to ANODE, triggering cathode current sink when input exceeds Vref - enabling closed-loop regulation without external op-amps.
It features sharp turn-on characteristics and stable operation across wide load and line variations, validated for Q-temp (−40°C to +125°C) automotive qualification. Dynamic impedance remains ≤0.5 Ω below 1 kHz, supporting fast transient response in switching power supply feedback paths.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reference Voltage | 2.495 V (nominal); enables precise 2.5 V–36 V output programming via two external resistors |
| Initial Tolerance | ±0.5% at 25°C (B grade); ensures tight output regulation without post-manufacturing trimming |
| Temp Range | −40°C to +125°C (Q grade); qualified for under-hood automotive and industrial ambient environments |
| Dynamic Impedance | 0.2 Ω typical (≤0.5 Ω max); maintains stable regulation under fast load transients in SMPS feedback loops |
| Sink Current Range | 1 mA to 100 mA; supports direct interface with optocoupler LEDs and error amplifier outputs |
| Ref Input Current | 2–4 µA typical; minimizes resistor-divider loading error and improves accuracy in high-impedance networks |
| Temp Drift (VI(dev)) | 14–34 mV over full range; verified stability for closed-loop systems requiring <0.1% output variation |
Pinout & Package
SOT-23-3 package (2.90 mm × 1.30 mm), surface-mount, lead-free, RoHS-compliant. Three-terminal configuration with no internal connections beyond functional pins.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1: Cathode | Shunt current output node | Connects to primary-side feedback network or optocoupler anode; sinks regulated current to maintain Vref at REF |
| Pin 2: Ref | Reference voltage sense input | High-impedance input (2–4 µA bias); compares external divider voltage to internal 2.495 V reference |
| Pin 3: Anode | Common return/reference ground | Must be connected to system ground or lowest potential point; serves as voltage reference for both REF and Cathode |
Key Features
| Feature | Design Value |
|---|---|
| Adjustable output voltage range | 2.5 V to 36 V via external resistor divider - eliminates need for multiple fixed-voltage references |
| Low output noise | Sub-20 µVRMS (0.1–10 Hz); reduces jitter and ripple in precision feedback paths |
| Sharp turn-on characteristic | Fast response to reference threshold crossing - enables stable regulation in discontinuous conduction mode (DCM) |
| Automotive temperature grade | Qualified per Q-temp (−40°C to +125°C) - meets AEC-Q100 stress test requirements for automotive power modules |
| ESD robustness | ±2000 V HBM - withstands handling and board assembly without additional protection circuitry |
Applications
| Rack Server Power Supply | Industrial AC/DC Converter |
|---|---|
Use Scenario: Secondary-side voltage feedback in isolated 48 V–12 V DC/DC modules with optocoupler isolation. IC Role / Device Role / Timing Role: Precision shunt reference setting feedback threshold for TL431BQDBVT-based error amplifier driving optocoupler LED. Use Value: Enables ±0.5% output regulation across line/load/temperature while maintaining safety isolation and meeting PMBus compliance. | Use Scenario: Output voltage regulation in 3 kW industrial rectifier with active PFC front-end and LLC resonant stage. IC Role / Device Role / Timing Role: Adjustable reference in secondary-side feedback loop, interfacing with TL384x PWM controller via optocoupler. Use Value: Delivers stable 24 V/48 V outputs across −40°C to +85°C ambient with <10 mV drift, reducing need for thermal compensation circuits. |
| AC Inverter Drive | Servo Drive Control Module |
Use Scenario: DC bus voltage sensing and regulation in 7.5 kW variable-frequency drive for HVAC compressors. IC Role / Device Role / Timing Role: Shunt reference in auxiliary 15 V bias supply feedback, ensuring stable gate driver operation during motor startup surges. Use Value: Maintains regulation under 100 mA peak sink current and 36 V cathode voltage, preventing brownout of control logic during transient overload. | Use Scenario: Isolated feedback for dual-output (±15 V) servo amplifier power stage supplying analog position feedback circuitry. IC Role / Device Role / Timing Role: Dual-reference implementation using single TL431BQDBVT with resistor network to set symmetric positive/negative rail thresholds. Use Value: Achieves matched ±0.5% tolerance on both rails without laser trimming, simplifying BOM and improving long-term drift tracking. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431CDBVT | Same SOT-23-3 package but C-temp grade (0°C to 70°C); ±0.5% tolerance; 6–16 mV temp drift | Limited to commercial-temperature applications (e.g., consumer adapters); not suitable for under-hood or factory-floor use | Select only if ambient stays within 0°C–70°C and cost sensitivity outweighs extended temp margin |
| TL431BIDBVT | Same B-grade tolerance but I-temp grade (−40°C to 85°C); 14–34 mV temp drift identical to TL431BQDBVT | Valid for industrial automation but not automotive under-hood; lower max junction temperature rating | Choose when full Q-temp range is unnecessary and supply chain availability favors I-grade stock |
Compared with TL431CDBVT and TL431BIDBVT, TL431BQDBVT uniquely supports −40°C to +125°C operation while retaining ±0.5% initial accuracy - critical for automotive engine control units, EV battery management interfaces, and high-reliability industrial inverters where thermal derating cannot be assumed.
Availability
TL431BQDBVT 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 TL431BQDBVT 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 company specializing in analog and embedded processing technologies, with leadership in power management, signal chain, and high-reliability components.
The TL431 product line delivers precision programmable shunt references for feedback control in isolated power supplies, designed specifically for automotive, industrial, and telecom infrastructure applications demanding tight tolerance and wide temperature stability.
FAQ
What is the reference voltage accuracy of TL431BQDBVT at 25°C?
The TL431BQDBVT has a reference voltage accuracy of ±0.5% at 25°C, corresponding to a nominal 2.495 V output with minimum 2.483 V and maximum 2.507 V. This B-grade tolerance is specified in Section 6.13 of the TI SLVS543S datasheet and applies exclusively to the Q-temp variant TL431BQDBVT.
Does TL431BQDBVT support operation above 85°C ambient temperature?
Yes, TL431BQDBVT is rated for operation from −40°C to +125°C ambient temperature (Q-grade), making it suitable for under-hood automotive applications and high-temperature industrial environments. Its thermal specifications are validated per JEDEC JESD22-A108 and include RθJA = 206°C/W in SOT-23-3 package.
Can TL431BQDBVT replace a Zener diode in feedback circuits?
Yes, TL431BQDBVT is explicitly designed as a superior replacement for Zener diodes in voltage regulation feedback paths. Its 0.2 Ω dynamic impedance, sharp turn-on, and programmable 2.5 V–36 V range provide tighter regulation, lower temperature drift, and higher sink-current capability than discrete Zeners - especially in isolated SMPS designs.
What is the maximum cathode voltage rating for TL431BQDBVT?
The absolute maximum cathode voltage (VKA) for TL431BQDBVT is 37 V, with recommended operating range from Vref (≈2.5 V) to 36 V. Exceeding 37 V risks permanent damage; operation at 36 V is supported across the full −40°C to +125°C temperature range per Section 6.1 Absolute Maximum Ratings.
How does TL431BQDBVT achieve low output noise performance?
TL431BQDBVT achieves low output noise through optimized bandgap core design and internal filtering, delivering <20 µVRMS (0.1–10 Hz) and sub-100 nV/√Hz broadband noise. This is measured per Figure 6-7 and 6-8 in the datasheet and enables clean feedback signals in high-resolution ADC references and low-jitter clock supplies.
TL431BQDBVT 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:
- ±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
TL431BQDBVT FAQ
1.How can I place an order for TL431BQDBVT through Aetrix?
Please submit a Request for Quotation (RFQ) for TL431BQDBVT 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 TL431BQDBVT reliable?
The price and inventory of TL431BQDBVT are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL431BQDBVT is usually 5 days.
3.What payment methods are accepted for TL431BQDBVT?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL431BQDBVT transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TL431BQDBVT?
TL431BQDBVT orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TL431BQDBVT 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 TL431BQDBVT?
For technical support, including TL431BQDBVT datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL431BQDBVT requirements.
6.How does Aetrix verify that TL431BQDBVT is sourced from the original manufacturer or authorized distributors?
All TL431BQDBVT 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 TL431BQDBVT meets industry standards.
7.What is the process for return or replacement of TL431BQDBVT?
All TL431BQDBVT units undergo pre-shipment inspection (PSI). If there is an issue with TL431BQDBVT, 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 TL431BQDBVT part is unused and in its original packaging.
Return procedure for TL431BQDBVT:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TL431BQDBVT Tags
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TL431BQDBZR
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AZ431LBNTR-G1
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LM4041DIM3-ADJ/NOPB
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LM4040DIM3X-2.5/NOPB
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AZ431LANTR-G1
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