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Texas Instruments TL431ACDE4
- Part No.:
- TL431ACDE4
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
TL431ACDE4.pdf
- Description:
- IC VREF SHUNT PREC ADJ 8-SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:5,200
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Product details
Overview
TL431ACDE4 from Texas Instruments is a precision programmable shunt voltage reference IC with 1% initial tolerance at 25°C, 2.47–2.52 V reference voltage, and operation across −40°C to 85°C. It delivers 0.2 Ω typical dynamic impedance, 1–100 mA sink-current capability, and low 0.8–1.2 µA reference input current drift over temperature - used for secondary-side regulation in flyback SMPSs and as a Zener diode replacement in adjustable power supplies.
For engineers reviewing the TL431ACDE4 datasheet, TL431ACDE4 pinout, TL431ACDE4 application, or TL431ACDE4 equivalent, this page provides verified electrical specifications, thermal behavior, package mapping to SOIC-8, functional pin roles, real-world use cases in voltage monitoring and comparator circuits, and two validated alternative parts with documented differences.
Technical Context
The TL431ACDE4 implements a three-terminal adjustable shunt regulator architecture with an internal error amplifier, reference voltage source, and NPN output transistor. Its cathode-anode voltage range spans 2.5 V to 36 V, and it maintains regulation with minimum cathode current of 0.4–0.6 mA.
It operates as a precision voltage-controlled current sink: the REF pin senses voltage relative to ANODE, triggering conduction between CATHODE and ANODE when the threshold is exceeded. Output impedance remains stable below 0.5 Ω up to 100 mA, enabling sharp turn-on and low-noise performance in feedback loops.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reference Voltage (Vref) | 2.47–2.52 V at 25°C - sets precise regulation point for external resistor divider networks |
| Initial Tolerance | ±1% at 25°C (A-grade) - enables accurate voltage setting without calibration in production |
| Operating Temperature | −40°C to +85°C (I-grade) - supports industrial and automotive ambient environments |
| Dynamic Impedance | 0.2 Ω typical - ensures minimal output voltage shift under load transients |
| Cathode Current Range | 1–100 mA - allows direct drive of optocoupler LEDs or feedback network biasing |
| Reference Input Current | 2–4 µA - imposes negligible loading on high-impedance sensing nodes |
| Temp Drift (VI(dev)) | 14–34 mV over full range - defines worst-case reference voltage excursion in thermal cycling |
| Min Cathode Current (Imin) | 0.4–0.6 mA - lowest current needed to sustain regulation; critical for light-load stability |
Pinout & Package
TL431ACDE4 is packaged in an 8-pin SOIC (Small Outline Integrated Circuit) body measuring 4.90 mm × 3.90 mm, with gull-wing leads and standard JEDEC MS-012AC footprint. This surface-mount package supports automated assembly and offers moderate thermal resistance (RθJA = 97°C/W).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (CATHODE) | Current Sink Output | Primary current path; connects to SMPS transformer secondary or feedback loop node |
| 2 (ANODE) | Common Reference Node | Typically tied to system ground or return path; all voltages referenced to this pin |
| 3 (REF) | Threshold Input | Senses voltage divider output; triggers conduction when ≥ Vref above ANODE |
| 4–8 (NC) | No Internal Connection | Unused pins; must remain unconnected per TI design guidelines |
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-voltage references |
| Low Output Impedance | 0.2 Ω typical - minimizes voltage droop during fast load steps in closed-loop regulation |
| Sharp Turn-On Characteristic | Active output circuitry enables rapid transition from off-state to regulation - improves transient response vs. passive Zeners |
| Low Reference Input Current | 2–4 µA - reduces divider resistor power loss and thermal drift in high-precision applications |
| Stable Over Temperature | 14–34 mV total deviation from −40°C to +85°C - maintains accuracy without external compensation |
Applications
| Secondary-Side Regulation | Zener Diode Replacement |
|---|---|
|
Use Scenario: Isolated DC-DC converter using optocoupler feedback to regulate output voltage on secondary side. IC Role / Device Role / Timing Role: TL431ACDE4 acts as error amplifier and reference, comparing sensed output voltage against internal Vref and driving optocoupler LED current. Use Value: Enables ±1% output regulation across line/load/temperature without primary-side controller complexity. |
Use Scenario: On-board 5 V or 12 V linear regulator requiring stable reference for pass transistor biasing. IC Role / Device Role / Timing Role: TL431ACDE4 replaces discrete Zener diodes by providing lower impedance, tighter tolerance, and better thermal stability. Use Value: Reduces output voltage drift by >5× versus 5% Zener diodes, improving system-level accuracy. |
| Voltage Monitoring | Comparator with Integrated Reference |
|
Use Scenario: Microcontroller supervisory circuit detecting brown-out or overvoltage conditions on 3.3 V rail. IC Role / Device Role / Timing Role: TL431ACDE4 configured as comparator with hysteresis via external resistors, comparing rail voltage to internal reference. Use Value: Eliminates need for external precision reference IC and op-amp, reducing BOM count and layout area. |
Use Scenario: Threshold detection in battery management system for cell overvoltage alarm. IC Role / Device Role / Timing Role: TL431ACDE4 functions as self-contained comparator: REF pin receives divided battery voltage; CATHODE drives alert signal. Use Value: Delivers sub-1% trip-point accuracy over −40°C to +85°C without trimming or calibration. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431ACD | Same SOIC-8 package, identical electrical specs, but no suffix 'E4' - RoHS-compliant variant without lead-free exemption marking | No functional difference; E4 denotes specific TI packaging and environmental compliance level | Select TL431ACD if RoHS-only compliance suffices and E4 traceability is not required for audit purposes |
| TL431AIDR | SOIC-8, same A-grade tolerance and I-temp range, but tape-and-reel packaging (DR suffix) and slightly higher max Ioff (0.5 µA vs. 0.5 µA typical) | Identical regulation performance; optimized for high-volume automated placement | Choose TL431AIDR for SMT production lines requiring reel-fed feeders and volume procurement support |
Compared with TL431ACDE4, TL431ACD offers identical functionality with simplified compliance labeling, while TL431AIDR adds tape-and-reel logistics optimization - both retain the same 1% tolerance, 0.2 Ω impedance, and −40°C to +85°C operation without layout or schematic changes.
Availability
TL431ACDE4 is available at Aetrix Electronics and suitable for industrial power supplies, automotive body control modules, and telecom infrastructure equipment requiring stable component supply across extended temperature ranges and multi-year production cycles.
Supply support for TL431ACDE4 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, with decades of experience in precision reference design and industrial-grade reliability validation.
The TL431 product line was engineered for high-accuracy voltage referencing in isolated power conversion, voltage supervision, and feedback control systems - delivering robust performance where Zener diodes fall short in stability and precision.
FAQ
What is the reference voltage tolerance of TL431ACDE4 at 25°C?
The TL431ACDE4 has a guaranteed initial reference voltage tolerance of ±1% at 25°C, corresponding to a Vref range of 2.47 V to 2.52 V under specified test conditions (VKA = Vref, IKA = 10 mA). This A-grade specification is confirmed in Section 7.8 of the official TI datasheet SLVS543P.
Does TL431ACDE4 require an external capacitor for stability?
TL431ACDE4 does not require an external capacitor for basic shunt regulation, but a 1 nF ceramic capacitor between REF and ANODE is recommended in noisy environments or high-frequency SMPS feedback paths to suppress oscillation. The device's internal compensation ensures stability with typical resistor-divider networks per TI Application Report SLVA289.
What is the maximum cathode-to-anode voltage rating for TL431ACDE4?
The absolute maximum cathode-to-anode voltage (VKA) for TL431ACDE4 is 37 V, with recommended operating range from Vref (≈2.5 V) to 36 V. Exceeding 37 V risks permanent damage; derating to ≤33 V is advised for long-term reliability in industrial designs.
Can TL431ACDE4 be used in place of a standard Zener diode?
Yes - TL431ACDE4 is explicitly designed as a superior Zener diode replacement. With 0.2 Ω dynamic impedance (vs. 10–100 Ω for Zeners), ±1% tolerance (vs. ±5%), and sharp turn-on, it delivers significantly better regulation accuracy, thermal stability, and noise immunity in applications like adjustable linear regulators and voltage clamping.
What is the minimum cathode current needed for TL431ACDE4 to maintain regulation?
The TL431ACDE4 requires a minimum cathode current (Imin) of 0.4–0.6 mA to sustain regulation, as specified in Section 7.8 of the datasheet. Below this threshold, the device exits active regulation mode and behaves as an open circuit - critical for designing light-load feedback networks in low-power SMPS designs.
TL431ACDE4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Series:
- -
- Packaging:
- Tube
- 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:
- ±1%
- Temperature Coefficient:
- -
- Noise - 0.1Hz to 10Hz:
- -
- Noise - 10Hz to 10kHz:
- -
- Voltage - Input:
- -
- Current - Supply:
- -
- Current - Cathode:
- 600 µA
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
TL431ACDE4 FAQ
1.How can I place an order for TL431ACDE4 through Aetrix?
Please submit a Request for Quotation (RFQ) for TL431ACDE4 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 TL431ACDE4 reliable?
The price and inventory of TL431ACDE4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL431ACDE4 is usually 5 days.
3.What payment methods are accepted for TL431ACDE4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL431ACDE4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TL431ACDE4?
TL431ACDE4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TL431ACDE4 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 TL431ACDE4?
For technical support, including TL431ACDE4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL431ACDE4 requirements.
6.How does Aetrix verify that TL431ACDE4 is sourced from the original manufacturer or authorized distributors?
All TL431ACDE4 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 TL431ACDE4 meets industry standards.
7.What is the process for return or replacement of TL431ACDE4?
All TL431ACDE4 units undergo pre-shipment inspection (PSI). If there is an issue with TL431ACDE4, 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 TL431ACDE4 part is unused and in its original packaging.
Return procedure for TL431ACDE4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TL431ACDE4 Tags
-
TL431AIDBZR
Texas Instruments
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TL431BQDBZR
Texas Instruments
-
AN431AN-ATRG1
Diodes Incorporated
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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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