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Texas Instruments TL431BQDBZTG4
- Part No.:
- TL431BQDBZTG4
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
TL431BQDBZTG4.pdf
- Description:
- IC VREF SHUNT ADJ 0.5% SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:4,259
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Product details
Overview
TL431BQDBZTG4 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 2.483 V to 2.507 V typical VREF. It delivers 1 mA to 100 mA sink current capability with 0.2 Ω typical dynamic impedance, used for feedback regulation in isolated DC/DC converters and industrial power supplies.
For engineers reviewing the TL431BQDBZTG4 datasheet, TL431BQDBZTG4 pinout, TL431BQDBZTG4 application, or TL431BQDBZTG4 equivalent, key selection criteria include automotive-grade thermal stability (Q-temp), tight 0.5% VREF accuracy, low 14–34 mV VREF drift over full temperature range, and compatibility with standard two-resistor external feedback networks.
Technical Context
The TL431BQDBZTG4 implements a three-terminal adjustable shunt regulator architecture with an internal error amplifier, reference voltage source, and output transistor. Its sharp turn-on characteristic enables precise regulation without external compensation in most applications.
It operates as a voltage-controlled current sink: when the REF pin voltage exceeds VREF, the cathode-anode path conducts to maintain VREF across external resistors. The Q-temp grade ensures specified performance from −40°C to +125°C, with VI(dev) ≤ 34 mV and II(dev) ≤ 2.5 µA over that range.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VREF tolerance @ 25°C | ±0.5% (B grade) - enables high-accuracy feedback loops without trimming |
| Operating temperature | −40°C to +125°C (Q grade) - qualified for under-hood automotive and industrial environments |
| VREF range | 2.483 V to 2.507 V - tightly centered on 2.495 V nominal for stable setpoint control |
| Dynamic impedance | 0.2 Ω typical - ensures minimal output voltage variation under load transients |
| Sink current range | 1 mA to 100 mA - supports direct drive of optocoupler LEDs or secondary-side error amplifiers |
| VKA max | 36 V - allows use in wide-input-voltage isolated flyback and forward converters |
| VREF drift (VI(dev)) | 14–34 mV over −40°C to +125°C - guarantees < ±1.4% total reference error in worst-case thermal conditions |
Pinout & Package
SOT-23-3 package (2.90 mm × 1.30 mm body size), surface-mount, lead-free and RoHS-compliant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1: REF | Reference input | High-impedance threshold node; regulates cathode current when voltage ≥ VREF |
| Pin 2: CATHODE | Current sink output | Primary conduction path; sinks up to 100 mA to maintain REF voltage |
| Pin 3: ANODE | Common return | Ground reference for REF and cathode; must be connected to system ground or lowest potential point |
Key Features
| Feature | Design Value |
|---|---|
| 0.5% initial VREF accuracy | Reduces need for post-manufacturing calibration in precision power supplies |
| Low 0.2 Ω dynamic impedance | Maintains stable regulation during fast load steps without external capacitance |
| 14–34 mV VREF deviation over −40°C to +125°C | Enables single-part qualification across automotive and industrial thermal profiles |
| 1 mA minimum cathode current for regulation | Allows operation with high-value feedback resistors to minimize quiescent power |
| Low 2–4 µA reference input current | Minimizes resistor-divider loading error and improves overall loop accuracy |
Applications
| AC Inverter Drive Feedback | Rack Server VRM Monitoring |
|---|---|
Use Scenario: Closed-loop voltage regulation in 3-phase motor drives using isolated flyback auxiliary supply. IC Role / Device Role / Timing Role: Shunt reference providing precise feedback to optocoupler-based primary-side controller. Use Value: 0.5% VREF tolerance ensures ±0.5% output voltage accuracy across temperature, critical for torque consistency. |
Use Scenario: Secondary-side monitoring of 12 V intermediate bus in multi-rail server power delivery. IC Role / Device Role / Timing Role: Precision shunt reference for analog supervisor ICs detecting overvoltage/undervoltage faults. Use Value: Q-temp rating guarantees reliable operation at 125°C board hotspots near CPUs/GPUs. |
| Industrial AC/DC Power Supply | Servo Drive Control Module |
Use Scenario: Output voltage regulation in DIN-rail mounted 24 V/5 A industrial SMPS. IC Role / Device Role / Timing Role: Adjustable shunt reference setting regulated output via resistor divider network. Use Value: 100 mA sink capability directly drives optocoupler LED without buffer transistor. |
Use Scenario: Isolated feedback path in servo amplifier's auxiliary 5 V logic supply. IC Role / Device Role / Timing Role: Voltage reference for secondary-side error amplifier in isolated DC/DC converter. Use Value: Low 2–4 µA IREF minimizes resistor-divider power loss and thermal drift in compact modules. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431BIDBZR | I-temp grade (−40°C to +85°C); same 0.5% VREF tolerance and SOT-23-3 package | Limited to commercial/industrial ambient environments; not qualified for extended automotive or high-temp industrial use | Select when full Q-temp range is unnecessary and cost optimization is prioritized |
| TL431CDBZR | C-temp grade (0°C to +70°C); 2% VREF tolerance; lower cost | Restricted to consumer or non-critical applications with controlled ambient and relaxed accuracy requirements | Choose only for cost-sensitive, non-automotive, room-temperature applications where ±2% regulation is acceptable |
Compared with TL431BIDBZR and TL431CDBZR, TL431BQDBZTG4 provides the widest temperature coverage and highest initial accuracy-making it the sole choice for designs requiring guaranteed 0.5% reference stability from −40°C to +125°C without derating.
Availability
TL431BQDBZTG4 is available at Aetrix Electronics and suitable for rack server power, industrial AC/DC, and servo drive control module applications requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for TL431BQDBZTG4 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 regulation in isolated power converters, designed specifically for automotive, industrial, and telecom power systems demanding high accuracy and thermal robustness.
FAQ
What is the reference voltage tolerance of TL431BQDBZTG4 at 25°C?
The TL431BQDBZTG4 has a reference voltage tolerance of ±0.5% at 25°C, corresponding to a VREF range of 2.483 V to 2.507 V. This B-grade accuracy is specified in Section 6.13 of the TI datasheet SLVS543S and applies exclusively to the Q-temp variant. The tolerance remains valid across the full −40°C to +125°C operating range, with total drift capped at 34 mV.
What package type does TL431BQDBZTG4 use?
TL431BQDBZTG4 uses the SOT-23-3 package (DBZ), with nominal body dimensions of 2.90 mm × 1.30 mm. Pin configuration is REF (Pin 1), CATHODE (Pin 2), and ANODE (Pin 3). This 3-pin surface-mount package is RoHS-compliant and optimized for space-constrained power supply feedback circuits.
Does TL431BQDBZTG4 support operation above 85°C?
Yes, TL431BQDBZTG4 is rated for continuous operation from −40°C to +125°C (Q-temp grade). Its electrical characteristics-including VREF, IREF, and dynamic impedance-are fully specified across this extended range per Section 6.13 of the datasheet. This makes TL431BQDBZTG4 suitable for under-hood automotive, industrial motor drives, and high-density server applications.
What is the maximum cathode voltage rating for TL431BQDBZTG4?
The absolute maximum cathode-to-anode voltage (VKA) for TL431BQDBZTG4 is 37 V, with recommended operating range from VREF to 36 V. This allows safe integration into isolated flyback, forward, and boost-derived auxiliary supplies with up to 36 V output. Exceeding 36 V risks violating recommended operating conditions and may impact long-term reliability.
How much current can TL431BQDBZTG4 sink in regulation mode?
TL431BQDBZTG4 supports a continuous cathode current range of 1 mA to 100 mA while maintaining regulation. Minimum cathode current (Imin) is 0.4–0.7 mA depending on temperature, ensuring stable operation even with high-value feedback resistors. The 100 mA upper limit enables direct drive of optocoupler LEDs without external buffering.
TL431BQDBZTG4 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:
- ±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-23-3
TL431BQDBZTG4 FAQ
1.How can I place an order for TL431BQDBZTG4 through Aetrix?
Please submit a Request for Quotation (RFQ) for TL431BQDBZTG4 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 TL431BQDBZTG4 reliable?
The price and inventory of TL431BQDBZTG4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL431BQDBZTG4 is usually 5 days.
3.What payment methods are accepted for TL431BQDBZTG4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL431BQDBZTG4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TL431BQDBZTG4?
TL431BQDBZTG4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TL431BQDBZTG4 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 TL431BQDBZTG4?
For technical support, including TL431BQDBZTG4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL431BQDBZTG4 requirements.
6.How does Aetrix verify that TL431BQDBZTG4 is sourced from the original manufacturer or authorized distributors?
All TL431BQDBZTG4 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 TL431BQDBZTG4 meets industry standards.
7.What is the process for return or replacement of TL431BQDBZTG4?
All TL431BQDBZTG4 units undergo pre-shipment inspection (PSI). If there is an issue with TL431BQDBZTG4, 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 TL431BQDBZTG4 part is unused and in its original packaging.
Return procedure for TL431BQDBZTG4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TL431BQDBZTG4 Tags
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TL431AIDBZR
Texas Instruments
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TL431BQDBZR
Texas Instruments
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AN431AN-ATRG1
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LM4040CYM3-2.5-TR
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LM4040CYM3-4.1-TR
Microchip Technology
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LM4040EIM3-2.5/NOPB
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AZ431LBNTR-G1
Diodes Incorporated
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LM4040D20IDBZR
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LM4041DIM3-ADJ/NOPB
Texas Instruments
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LM4040DIM3X-2.5/NOPB
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LM4040DIM3-2.5/NOPB
Texas Instruments
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AZ431LANTR-G1
Diodes Incorporated
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