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Texas Instruments TL431AQDBVRG4
- Part No.:
- TL431AQDBVRG4
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- SC-74A, SOT-753
- Datasheet:
-
TL431AQDBVRG4.pdf
- Description:
- IC VREF SHUNT ADJ 1% SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:1,339
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Product details
Overview
TL431AQDBVRG4 from Texas Instruments is a precision programmable shunt voltage reference in SOT-23-3 package, delivering 2.47–2.52 V reference voltage (A-grade, ±1% at 25°C), operating across −40°C to +125°C, with 14–34 mV total reference voltage drift over temperature and 0.2 Ω typical dynamic impedance. It serves as a stable feedback element in isolated DC-DC converters and industrial power supplies.
For engineers reviewing the TL431AQDBVRG4 datasheet, TL431AQDBVRG4 pinout, TL431AQDBVRG4 application, or TL431AQDBVRG4 equivalent, key selection criteria include automotive-grade temperature range (−40°C to 125°C), A-grade initial accuracy (±1%), low output impedance for loop stability, and SOT-23-3 footprint compatibility with space-constrained PCB layouts.
Technical Context
The TL431AQDBVRG4 implements an adjustable shunt regulator architecture with internal error amplifier, reference, and NPN pass transistor. Its REF pin senses voltage relative to ANODE, triggering cathode current sink when input exceeds Vref - enabling precise closed-loop regulation without external op-amps.
It operates as a 3-terminal device requiring only two external resistors to set output voltage from 2.5 V to 36 V. The Q-temp qualification ensures robust performance in automotive and industrial environments where thermal stress and long-term stability are critical.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reference Voltage | 2.47–2.52 V at 25°C (A-grade ±1% tolerance; sets feedback threshold in SMPS) |
| Temp Range | −40°C to +125°C (Q-temp qualified; supports under-hood automotive & industrial control) |
| Ref Voltage Drift | 14–34 mV over full temp range (ensures <0.14% output variation in 12 V supply) |
| Dynamic Impedance | 0.2 Ω typical (minimizes AC error in feedback path; improves transient response) |
| Cathode Current | 1–100 mA sink capability (supports direct optocoupler drive in isolated flyback designs) |
| Reference Input Current | 2–4 µA (low bias current enables high-resistor-divider networks for low quiescent power) |
| Off-State Leakage | 0.1–0.5 µA at 36 V (prevents false turn-on in high-voltage standby circuits) |
Pinout & Package
SOT-23-3 package (2.90 mm × 1.30 mm), surface-mount, lead-free, RoHS-compliant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1: Cathode | Shunt current output node | Sinks regulated current into external circuit; connects to optocoupler LED or feedback divider bottom |
| Pin 2: Anode | Common reference return | Typically tied to system ground or power rail return; defines voltage reference point for REF |
| Pin 3: Ref | Threshold sense input | Compares external voltage against internal 2.5 V bandgap; triggers cathode conduction when exceeded |
Key Features
| Feature | Design Value |
|---|---|
| Adjustable output voltage | Configurable from 2.5 V to 36 V using two external resistors - eliminates need for multiple fixed references |
| Low output noise | Sub-20 µVRMS (0.1–10 Hz); preserves signal integrity in precision analog feedback loops |
| Sharp turn-on characteristic | Fast response to reference threshold crossing - enables stable regulation in fast-transient power stages |
| High sink-current capability | 100 mA max cathode current - directly drives optocouplers without buffer transistors |
| Automotive temperature grade | Qualified per AEC-Q100 (Q-temp) - validated for engine control units and ADAS power rails |
Applications
| Rack Server Power | Industrial AC/DC Converter |
|---|---|
Use Scenario: Secondary-side voltage regulation in 48 V input, 12 V/50 A telecom rectifier modules. IC Role / Device Role / Timing Role: Shunt reference in optocoupler-coupled feedback loop, setting output voltage via resistor divider on REF pin. Use Value: ±1% initial accuracy and <34 mV temp drift maintain tight output tolerance across full load and ambient range. | Use Scenario: Output voltage sensing in 3-phase industrial motor drive power supply (24 V/10 A). IC Role / Device Role / Timing Role: Precision shunt reference providing stable feedback to PWM controller IC. Use Value: 0.2 Ω dynamic impedance ensures minimal phase shift in control loop, improving stability margin. |
| AC Inverter Drive | Servo Drive Control Module |
Use Scenario: DC bus voltage monitoring and regulation in variable-frequency HVAC inverter (300–400 V DC bus). IC Role / Device Role / Timing Role: High-voltage feedback reference with resistor divider scaling; cathode sinks current into isolation barrier. Use Value: 36 V max cathode voltage rating and −40°C to +125°C operation support harsh inverter environments. | Use Scenario: Isolated auxiliary supply regulation in servo amplifier PCB (5 V @ 2 A output). IC Role / Device Role / Timing Role: Reference element in flyback converter feedback network, interfacing with PC817 optocoupler. Use Value: 100 mA sink current drives optocoupler LED directly, eliminating discrete transistor stage and reducing BOM count. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431AIDBVR | I-temp grade (−40°C to +85°C); same A-grade accuracy and SOT-23-3 package | Limited to commercial/industrial ambient; not qualified for under-hood automotive use | Select when full Q-temp range is unnecessary and cost optimization is prioritized |
| TL431BQDBVRG4 | B-grade accuracy (±0.5% at 25°C); identical Q-temp rating and SOT-23-3 footprint | Higher precision required for lab-grade instrumentation or high-end server VRMs | Choose when tighter initial tolerance justifies marginal cost increase and layout reuse is critical |
Compared with TL431AIDBVR, TL431AQDBVRG4 adds 40°C higher upper temperature limit and automotive qualification; compared with TL431BQDBVRG4, it trades 0.5% accuracy for lower unit cost while retaining full Q-temp reliability - making it optimal for cost-sensitive automotive body electronics and industrial controls.
Availability
TL431AQDBVRG4 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 multi-year production cycles.
Supply support for TL431AQDBVRG4 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 technologies, serving automotive, industrial, and communications markets.
The TL431 product line delivers precision programmable shunt references for feedback regulation in isolated power supplies, battery management, and voltage monitoring - designed specifically for high-reliability, thermally demanding applications.
FAQ
What is the reference voltage tolerance of TL431AQDBVRG4 at 25°C?
The TL431AQDBVRG4 has an initial reference voltage tolerance of ±1% at 25°C (A-grade), corresponding to a 2.47–2.52 V range. This specification is guaranteed per TI's SLVS543S datasheet Section 6.10 and applies across the full SOT-23-3 packaged device family. The TL431AQDBVRG4 maintains this accuracy without calibration and is validated during production test.
Does TL431AQDBVRG4 support operation at 125°C ambient temperature?
Yes, TL431AQDBVRG4 is Q-temp qualified for continuous operation from −40°C to +125°C ambient temperature. Its electrical characteristics - including reference voltage drift (14–34 mV), dynamic impedance (0.2 Ω), and cathode current capability (1–100 mA) - are fully specified and tested across this range per Section 6.7 and 6.10 of the TI datasheet.
Can TL431AQDBVRG4 replace a Zener diode in a feedback circuit?
Yes, TL431AQDBVRG4 is explicitly designed as a superior replacement for Zener diodes in voltage regulation and feedback applications. Its sharp turn-on characteristic, low dynamic impedance (0.2 Ω), and adjustable output (2.5–36 V) enable more accurate, stable, and temperature-invariant regulation than discrete Zeners - especially in isolated SMPS feedback paths where TL431AQDBVRG4 drives optocouplers directly.
What is the minimum cathode current required for regulation in TL431AQDBVRG4?
The TL431AQDBVRG4 requires a minimum cathode current of 0.4–0.7 mA to maintain regulation, as specified in Section 6.10 of the TI datasheet. This value ensures the internal amplifier remains active and the reference stays stable. Below this threshold, the device exits regulation and cathode voltage rises toward the cathode supply rail.
Is TL431AQDBVRG4 pin-compatible with other TL431 variants in SOT-23-3?
Yes, TL431AQDBVRG4 uses the standard TL431 SOT-23-3 pinout (Cathode–Anode–Ref), matching all TL431x and TL432x devices in DBZ package per Table 5-1 and Figure 5-1 of the TI datasheet. No PCB layout changes are needed when upgrading from C- or I-temp grades or switching between A- and B-grade variants in the same package.
TL431AQDBVRG4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- SC-74A, SOT-753
- 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:
- ±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
TL431AQDBVRG4 FAQ
1.How can I place an order for TL431AQDBVRG4 through Aetrix?
Please submit a Request for Quotation (RFQ) for TL431AQDBVRG4 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 TL431AQDBVRG4 reliable?
The price and inventory of TL431AQDBVRG4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL431AQDBVRG4 is usually 5 days.
3.What payment methods are accepted for TL431AQDBVRG4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL431AQDBVRG4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TL431AQDBVRG4?
TL431AQDBVRG4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TL431AQDBVRG4 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 TL431AQDBVRG4?
For technical support, including TL431AQDBVRG4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL431AQDBVRG4 requirements.
6.How does Aetrix verify that TL431AQDBVRG4 is sourced from the original manufacturer or authorized distributors?
All TL431AQDBVRG4 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 TL431AQDBVRG4 meets industry standards.
7.What is the process for return or replacement of TL431AQDBVRG4?
All TL431AQDBVRG4 units undergo pre-shipment inspection (PSI). If there is an issue with TL431AQDBVRG4, 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 TL431AQDBVRG4 part is unused and in its original packaging.
Return procedure for TL431AQDBVRG4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TL431AQDBVRG4 Tags
-
TL431AIDBZR
Texas Instruments
-
TL431BQDBZR
Texas Instruments
-
AN431AN-ATRG1
Diodes Incorporated
-
LM4040CYM3-2.5-TR
Microchip Technology
-
LM4040CYM3-4.1-TR
Microchip Technology
-
LM4040EIM3-2.5/NOPB
Texas Instruments
-
AZ431LBNTR-G1
Diodes Incorporated
-
LM4040D20IDBZR
Texas Instruments
-
LM4041DIM3-ADJ/NOPB
Texas Instruments
-
LM4040DIM3X-2.5/NOPB
Texas Instruments
-
LM4040DIM3-2.5/NOPB
Texas Instruments
-
AZ431LANTR-G1
Diodes Incorporated
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