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Texas Instruments TL431IDRE4
- Part No.:
- TL431IDRE4
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
TL431IDRE4.pdf
- Description:
- IC VREF SHUNT ADJ 2.2% 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:3,601
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Product details
Overview
TL431IDRE4 from Texas Instruments is a precision programmable shunt voltage reference IC with 1% initial tolerance (A grade) at 25°C, adjustable output voltage from 2.495 V to 36 V, and operation across −40°C to 85°C. It delivers 0.2 Ω typical dynamic impedance, 1–100 mA sink-current capability, and low output noise-enabling accurate feedback in isolated DC-DC converters for industrial AC/DC power supplies.
For engineers reviewing the TL431IDRE4 datasheet, TL431IDRE4 pinout, TL431IDRE4 application, or TL431IDRE4 equivalent, key selection criteria include reference accuracy over temperature, cathode current range, dynamic impedance stability, and compatibility with SOT-23-3 PCB layouts in space-constrained power regulation designs.
Technical Context
The TL431IDRE4 implements a three-terminal adjustable shunt regulator architecture with an internal error amplifier, reference voltage source, and output transistor. Its sharp turn-on characteristic and active output circuitry replace discrete Zener diodes in closed-loop feedback paths.
It operates as a two-input comparator: the REF pin senses voltage relative to ANODE, while the CATHODE sinks current proportional to the error between sensed voltage and internal 2.495 V reference. Stability depends on external resistor network and load capacitance, with oscillation boundaries documented per cathode voltage and current conditions.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reference Voltage | 2.495 V ±1% at 25°C - sets precise feedback threshold for output regulation |
| Adjustable Range | 2.495 V to 36 V - enables flexible output setting via two external resistors |
| Temp Range | −40°C to +85°C - supports industrial ambient operation without derating |
| Dynamic Impedance | 0.2 Ω typical - ensures minimal output voltage shift under load transients |
| Sink Current | 1 mA to 100 mA - provides sufficient drive for optocoupler LEDs in isolated flyback controllers |
| Output Noise | Low - reduces feedback path jitter in high-accuracy voltage regulation |
| Ref Input Current | 2–4 µA - enables high-impedance resistor dividers without significant error |
Pinout & Package
TL431IDRE4 is housed in a SOT-23-3 package (2.90 mm × 1.30 mm), with pins arranged in standard top-view orientation: Pin 1 = REF, Pin 2 = CATHODE, Pin 3 = ANODE.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| REF (Pin 1) | Reference input | Senses divided output voltage; must be biased within 2.495 V ±0.5 V of ANODE to maintain regulation |
| CATHODE (Pin 2) | Current sink output | Drains regulated current into feedback loop; connects to optocoupler LED anode in isolated PSUs |
| ANODE (Pin 3) | Common return | Typically tied to system ground or negative rail; serves as voltage reference point for REF and CATHODE |
Key Features
| Feature | Design Value |
|---|---|
| 1% Initial Accuracy (A Grade) | Reduces calibration overhead in factory-trimmed power supplies |
| 0.2 Ω Dynamic Impedance | Maintains tight output voltage control during line/load transients |
| 1–100 mA Sink Capability | Directly drives standard optocouplers (e.g., PC817) without buffer stages |
| −40°C to +85°C Operation | Validates performance across full industrial temperature range without external compensation |
| Low Reference Input Current | Enables use of >1 MΩ resistor dividers, minimizing power loss and thermal drift |
Applications
| Rack Server Power | Industrial AC/DC |
|---|---|
Use Scenario: Secondary-side voltage feedback in 48 V input, 12 V/50 A isolated DC-DC modules. IC Role / Device Role / Timing Role: Precision shunt reference providing error signal to optocoupler-driven primary controller. Use Value: 1% reference accuracy ensures ±0.12 V output tolerance across temperature, meeting server PSU efficiency and reliability specs. | Use Scenario: Output regulation in 3-phase rectified 380 VAC-to-24 VDC industrial power supplies. IC Role / Device Role / Timing Role: Adjustable shunt reference in feedback loop of flyback or forward converter. Use Value: Adjustable 2.495–36 V range allows single BOM for multiple output voltages; SOT-23-3 footprint saves board space. |
| AC Inverter Drives | Servo Drive Control Module |
Use Scenario: DC bus voltage monitoring and regulation in VFDs with regenerative braking. IC Role / Device Role / Timing Role: Shunt reference for analog-to-digital converter input scaling and overvoltage protection thresholds. Use Value: Stable 2.495 V reference enables accurate ADC measurement of 0–800 V DC bus with <0.5% total error. | Use Scenario: Isolated feedback for dual-output (±15 V) auxiliary supply powering gate drivers and op-amps. IC Role / Device Role / Timing Role: Dual-shunt reference generating matched positive/negative regulation points. Use Value: Matched tempco and low noise ensure symmetrical rail tracking critical for precision servo current loops. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431ACDRE4 | 0.5% initial tolerance (B grade), same SOT-23-3 package and electrical specs | Higher accuracy required for metrology-grade power supplies or lab equipment | Select when tighter reference stability justifies cost premium and layout remains identical |
| TL431ILP | SOIC-8 package, same A-grade accuracy and −40°C to +85°C rating | Requires PCB redesign; preferred where higher power dissipation or manual assembly is needed | Choose for through-hole prototyping, higher thermal mass, or legacy SOIC footprints |
Compared with TL431ACDRE4 and TL431ILP, TL431IDRE4 offers optimal balance of industrial-grade accuracy, compact SOT-23-3 footprint, and proven stability in high-density power modules-making it the default choice for cost-sensitive, volume industrial designs.
Availability
TL431IDRE4 is available at Aetrix Electronics and suitable for rack server power, industrial AC/DC, and servo drive control module applications requiring stable component supply and long-term production continuity.
Supply support for TL431IDRE4 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.
The TL431 product line delivers precision programmable shunt references for feedback regulation in isolated and non-isolated power converters across industrial, computing, and automotive systems.
FAQ
What is the reference voltage tolerance of TL431IDRE4 at 25°C?
The TL431IDRE4 has a 1% initial reference voltage tolerance at 25°C (A grade), meaning its Vref is specified between 2.470 V and 2.520 V under nominal conditions. This tolerance is confirmed in TI's SLVS543S datasheet Section 6.9 for TL431AI devices. The TL431IDRE4 part number explicitly denotes the I-temp (−40°C to +85°C) and A-grade accuracy variant.
What package type does TL431IDRE4 use?
TL431IDRE4 uses the SOT-23-3 surface-mount package (2.90 mm × 1.30 mm body size), with pinout: Pin 1 = REF, Pin 2 = CATHODE, Pin 3 = ANODE. This is verified in TI's device nomenclature guide and mechanical drawings in the SLVS543S datasheet Section 12.
Can TL431IDRE4 replace a Zener diode in feedback circuits?
Yes, TL431IDRE4 is designed as a direct functional replacement for Zener diodes in voltage regulation feedback paths. Its active topology provides sharper knee characteristics, lower dynamic impedance (0.2 Ω vs typical Zener's 5–50 Ω), and adjustable output-making it ideal for optocoupler-based isolation in flyback converters.
What is the minimum cathode current required for TL431IDRE4 regulation?
The TL431IDRE4 requires a minimum cathode current of 0.4 mA to maintain regulation, as specified in Section 6.9 of the SLVS543S datasheet under "Imin". Below this threshold, the device exits regulation and output voltage becomes undefined.
Does TL431IDRE4 support operation beyond 85°C ambient?
No-TL431IDRE4 is rated for −40°C to +85°C operating free-air temperature (I-grade). For extended temperature operation up to +125°C, the Q-grade variant TL431IQDBVR is required. Using TL431IDRE4 above 85°C risks parametric shift and potential failure per TI's recommended operating conditions.
TL431IDRE4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- 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:
- ±2.2%
- Temperature Coefficient:
- -
- Noise - 0.1Hz to 10Hz:
- -
- Noise - 10Hz to 10kHz:
- -
- Voltage - Input:
- -
- Current - Supply:
- -
- Current - Cathode:
- 1 mA
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
TL431IDRE4 FAQ
1.How can I place an order for TL431IDRE4 through Aetrix?
Please submit a Request for Quotation (RFQ) for TL431IDRE4 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 TL431IDRE4 reliable?
The price and inventory of TL431IDRE4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL431IDRE4 is usually 5 days.
3.What payment methods are accepted for TL431IDRE4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL431IDRE4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TL431IDRE4?
TL431IDRE4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TL431IDRE4 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 TL431IDRE4?
For technical support, including TL431IDRE4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL431IDRE4 requirements.
6.How does Aetrix verify that TL431IDRE4 is sourced from the original manufacturer or authorized distributors?
All TL431IDRE4 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 TL431IDRE4 meets industry standards.
7.What is the process for return or replacement of TL431IDRE4?
All TL431IDRE4 units undergo pre-shipment inspection (PSI). If there is an issue with TL431IDRE4, 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 TL431IDRE4 part is unused and in its original packaging.
Return procedure for TL431IDRE4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TL431IDRE4 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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