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Texas Instruments TL431AQDBVRE4
- Part No.:
- TL431AQDBVRE4
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- SC-74A, SOT-753
- Datasheet:
-
TL431AQDBVRE4.pdf
- Description:
- IC VREF SHUNT ADJ 1% SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:2,355
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Product details
Overview
TL431AQDBVRE4 from Texas Instruments is a precision programmable shunt voltage reference in SOT-23-3 package, delivering 2.47 V to 2.52 V reference voltage at 25°C with ±1% initial tolerance (A grade), 14 mV max reference voltage drift over −40°C to +125°C (Q grade), 0.2 Ω typical dynamic impedance, and 1 mA to 100 mA sink-current capability. It serves as an adjustable voltage reference in secondary-side regulation of isolated flyback SMPSs.
For engineers reviewing the TL431AQDBVRE4 datasheet, TL431AQDBVRE4 pinout, TL431AQDBVRE4 application, or TL431AQDBVRE4 equivalent, key selection criteria include automotive-grade temperature range (−40°C to 125°C), low output impedance for stable feedback loops, minimal reference input current (2–4 µA), and compatibility with two-resistor external programming for output voltages from 2.5 V to 36 V.
Technical Context
The TL431AQDBVRE4 implements a three-terminal adjustable shunt regulator architecture with an internal error amplifier, reference voltage source, and NPN output transistor. Its sharp turn-on characteristic and low 0.2 Ω dynamic impedance enable precise regulation without external compensation in most feedback networks.
Designed for automotive applications, the Q-grade device operates across −40°C to +125°C with guaranteed 14 mV max reference voltage deviation over temperature and 0.8–2.5 µA reference input current variation - enabling high-accuracy closed-loop control in harsh environments.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Vref @ 25°C | 2470–2520 mV (±1% A-grade accuracy enables tight output voltage setpoint in power supplies) |
| VI(dev) over temp | 14–34 mV (max deviation across −40°C to +125°C ensures stable regulation in automotive underhood) |
| IKA range | 1–100 mA (supports direct sinking of optocoupler LED current or error amplifier load) |
| |zKA| dynamic impedance | 0.2–0.5 Ω (low output impedance maintains loop stability without added capacitance) |
| Iref input current | 2–4 µA (ultra-low bias current minimizes resistor-divider loading error) |
| Min cathode current | 0.4–0.7 mA (enables reliable regulation even at light loads in standby modes) |
| Off-state IKA | 0.1–0.5 µA (ensures negligible leakage when reference is disabled) |
Pinout & Package
SOT-23-3 package (2.90 mm × 1.30 mm body size), surface-mount, lead-free, RoHS-compliant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1: Cathode | Current sink node | Connects to feedback network output; sinks regulated current to maintain VREF at divider junction |
| Pin 2: Anode | Reference ground reference | Common return path; must be tied to system ground or lowest potential point in feedback loop |
| Pin 3: Ref | Threshold input | Compares external resistor-divider voltage against internal 2.5 V reference; triggers conduction when ≥Vref |
Key Features
| Feature | Design Value |
|---|---|
| Adjustable output voltage | 2.5 V to 36 V via two external resistors - eliminates need for multiple fixed references |
| Automotive temperature range | −40°C to +125°C operation - qualified for engine control, ADAS, and infotainment systems |
| Low output noise & impedance | 0.2 Ω typical dynamic impedance and low noise support clean feedback in sensitive analog circuits |
| Zener diode replacement | Sharp turn-on and tighter tolerance replace discrete Zeners in voltage monitoring and clamping |
| Low reference input current | 2–4 µA Iref reduces resistor-divider power loss and improves accuracy in high-impedance networks |
Applications
| Secondary-Side Flyback Regulation | Overvoltage Monitoring |
|---|---|
Use Scenario: Isolated DC-DC converter using optocoupler feedback to regulate output voltage on secondary side. IC Role / Device Role / Timing Role: Shunt reference providing precise 2.5 V threshold to drive optocoupler LED; sets feedback voltage proportional to output. Use Value: Enables ±1% output regulation across line/load/temperature without primary-side sensing components. |
Use Scenario: Protection circuit detecting excessive bus voltage before damage occurs to downstream ICs. IC Role / Device Role / Timing Role: Adjustable comparator reference; triggers shutdown when sensed voltage exceeds programmed threshold. Use Value: Programmable trip point (e.g., 12.5 V via 5× resistor ratio) with <14 mV drift ensures consistent protection margin over temperature. |
| Zener Diode Replacement | Programmable Current Sink |
Use Scenario: Low-cost voltage clamp in LDO biasing or ADC reference buffer circuits. IC Role / Device Role / Timing Role: Precision shunt element replacing 2.5 V Zener; provides stable reference with lower dynamic impedance. Use Value: 0.2 Ω impedance vs. typical 10–50 Ω Zener yields tighter regulation under varying load currents. |
Use Scenario: Constant-current source for LED biasing or sensor excitation in automotive modules. IC Role / Device Role / Timing Role: Regulated shunt controlling current through external pass transistor or LED string. Use Value: 1–100 mA sink range supports scalable current setting with <1% initial accuracy and minimal thermal drift. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431ACDBVR | Same SOT-23-3 package, C-grade (0°C to 70°C), ±1% tolerance, 6–16 mV Vref drift | Limited to commercial temperature range; unsuitable for underhood or industrial ambient | Select only for cost-sensitive non-automotive designs where full −40°C to +125°C operation is unnecessary |
| TL431BQDBVR | Same Q-grade temp range and SOT-23-3 package, but ±0.5% (B-grade) tolerance, 14–34 mV Vref drift | Higher accuracy enables tighter output regulation in premium power supplies or safety-critical monitoring | Choose when reference stability below ±5 mV total deviation is required; trades higher cost for improved precision |
Compared with TL431AQDBVRE4, TL431ACDBVR sacrifices automotive temperature capability for lower cost, while TL431BQDBVR delivers tighter initial tolerance at identical operating range - allowing designers to optimize for accuracy, environmental robustness, or BOM cost.
Availability
TL431AQDBVRE4 is available at Aetrix Electronics and suitable for automotive power management, isolated DC-DC converters, and voltage supervision systems requiring stable component supply with guaranteed long-term availability.
Supply support for TL431AQDBVRE4 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 precision analog ICs and automotive-grade components.
The TL431 product line delivers programmable shunt references optimized for feedback accuracy, thermal stability, and reliability in power conversion and voltage monitoring - targeting automotive, industrial, and communications infrastructure.
FAQ
What is the reference voltage tolerance of TL431AQDBVRE4 at 25°C?
The TL431AQDBVRE4 has a reference voltage tolerance of ±1% at 25°C, corresponding to a 2470 mV to 2520 mV range. This A-grade specification is confirmed in Section 7.10 of the official TI datasheet SLVS543P, and applies specifically to the Q-temperature-grade variant in SOT-23-3 packaging.
Does TL431AQDBVRE4 support operation across the full automotive temperature range?
Yes, TL431AQDBVRE4 is rated for operation from −40°C to +125°C (Q-grade), making it suitable for underhood and other harsh automotive environments. Its maximum reference voltage deviation over this range is 14–34 mV, as specified in the TL431AQ electrical characteristics table (Section 7.10).
What is the minimum cathode current required for regulation in TL431AQDBVRE4?
The TL431AQDBVRE4 requires a minimum cathode current of 0.4 mA to 0.7 mA for proper regulation, depending on operating conditions. This value is documented in Section 7.10 of the datasheet under "Imin" and ensures stable feedback behavior even during light-load or standby operation.
Can TL431AQDBVRE4 replace a standard Zener diode in voltage reference circuits?
Yes, TL431AQDBVRE4 is explicitly designed as a precision Zener diode replacement. Its sharp turn-on characteristic, 0.2 Ω dynamic impedance, and ±1% reference accuracy provide superior regulation stability compared to discrete Zeners - especially in feedback loops of switching power supplies and voltage monitors.
What is the reference input current (Iref) specification for TL431AQDBVRE4?
The reference input current for TL431AQDBVRE4 is 2 µA to 4 µA at 25°C, as specified in Section 7.10 of the TI datasheet. This ultra-low Iref minimizes loading error in high-impedance resistor-divider networks used to program output voltage.
TL431AQDBVRE4 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:
- ±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-23-5
TL431AQDBVRE4 FAQ
1.How can I place an order for TL431AQDBVRE4 through Aetrix?
Please submit a Request for Quotation (RFQ) for TL431AQDBVRE4 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 TL431AQDBVRE4 reliable?
The price and inventory of TL431AQDBVRE4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL431AQDBVRE4 is usually 5 days.
3.What payment methods are accepted for TL431AQDBVRE4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL431AQDBVRE4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TL431AQDBVRE4?
TL431AQDBVRE4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TL431AQDBVRE4 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 TL431AQDBVRE4?
For technical support, including TL431AQDBVRE4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL431AQDBVRE4 requirements.
6.How does Aetrix verify that TL431AQDBVRE4 is sourced from the original manufacturer or authorized distributors?
All TL431AQDBVRE4 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 TL431AQDBVRE4 meets industry standards.
7.What is the process for return or replacement of TL431AQDBVRE4?
All TL431AQDBVRE4 units undergo pre-shipment inspection (PSI). If there is an issue with TL431AQDBVRE4, 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 TL431AQDBVRE4 part is unused and in its original packaging.
Return procedure for TL431AQDBVRE4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TL431AQDBVRE4 Tags
-
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
-
AZ431LANTR-G1
Diodes Incorporated
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