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Texas Instruments TL431CLPE3
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- Part No.:
- TL431CLPE3
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- TO-226-3, TO-92-3 (TO-226AA)
- Datasheet:
-
TL431CLPE3.pdf
- Description:
- IC VREF SHUNT ADJ 2.2% TO92-3
- Quantity:
- Payment:
- Shipping:
Inventory:3,548
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Product details
Overview
TL431CLPE3 from Texas Instruments is a precision programmable shunt voltage reference IC in SOIC-8 package, delivering 2.495 V nominal reference voltage with ±0.5% initial tolerance (B grade), 0.2 Ω typical dynamic impedance, and operation across −40°C to 85°C (I-grade). It replaces Zener diodes in feedback loops of isolated DC/DC converters, AC/DC power supplies, and servo drive control modules.
For engineers reviewing the TL431CLPE3 datasheet, TL431CLPE3 pinout, TL431CLPE3 application, or TL431CLPE3 equivalent, key selection criteria include its adjustable output range (2.5 V to 36 V), low temperature drift (14 mV over −40°C to 85°C), sink-current capability (1–100 mA), and SOIC-8 thermal performance (RθJA = 97°C/W).
Technical Context
The TL431CLPE3 implements a three-terminal adjustable shunt regulator architecture with an internal error amplifier, reference voltage source, and NPN output stage. Its sharp turn-on characteristic and active output circuitry enable stable regulation without external compensation in most linear and switching power supply feedback paths.
As an I-grade B-tolerance device, TL431CLPE3 is characterized for −40°C to 85°C operation and exhibits 14 mV maximum reference voltage deviation over that range. Its cathode-to-anode voltage range spans 2.5 V to 36 V, with minimum regulation current of 0.4 mA and off-state cathode leakage below 0.5 µA at 36 V.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reference Voltage | 2.495 V ±0.5% at 25°C - sets precise feedback threshold for power supply regulation |
| Temperature Range | −40°C to +85°C - qualified for industrial-grade embedded power systems |
| Dynamic Impedance | 0.2 Ω typical - ensures minimal output voltage variation under load transients |
| Sink Current Range | 1 mA to 100 mA - supports direct interface with optocoupler LEDs in isolated flyback designs |
| Reference Input Current | 2–4 µA - enables high-impedance resistor-divider networks without significant loading error |
| Output Noise | Low broadband noise - critical for low-noise analog references and precision feedback loops |
| Max Cathode Voltage | 36 V - allows use in wide-input-voltage industrial and server power rails |
Pinout & Package
TL431CLPE3 is housed in an 8-pin SOIC (Small Outline Integrated Circuit) package measuring 4.90 mm × 3.90 mm, with standard JEDEC MS-012AC footprint and gull-wing leads. Thermal resistance is RθJA = 97°C/W, enabling reliable operation at up to 100 mA sink current in ambient temperatures ≤85°C.
| Pin | Circuit Role | Design Meaning |
|---|---|---|
| 1 | CATHODE | Shunt current input node; connects to switched node or optocoupler anode in feedback loop |
| 2 | ANODE | Common return path; typically tied to system ground or power rail reference point |
| 3 | ANODE | No internal connection (NC) - electrically isolated in SOIC-8 layout per TI pin mapping |
| 4 | ANODE | No internal connection (NC) - unused terminal; must be left floating or grounded per layout guidelines |
| 5 | REF | Internal 2.495 V reference input; connects to resistor divider midpoint for output voltage programming |
| 6 | ANODE | No internal connection (NC) - unused terminal; no electrical function in TL431CLPE3 |
| 7 | ANODE | No internal connection (NC) - redundant anode pad; not bonded in SOIC-8 variant |
| 8 | ANODE | No internal connection (NC) - electrically isolated; no impact on regulation behavior |
Key Features
| Feature | Design Value |
|---|---|
| Programmable Output | Adjustable from 2.5 V to 36 V using two external resistors - eliminates need for multiple fixed-reference parts |
| Thermal Stability | 14 mV max Vref deviation over −40°C to +85°C - ensures consistent regulation across industrial environments |
| Low Dynamic Impedance | 0.2 Ω typical - maintains tight output voltage control during rapid load changes in SMPS feedback |
| Zener Replacement | Sharp turn-on and low noise - provides superior regulation accuracy and transient response vs. discrete Zener diodes |
| High Sink Capability | 100 mA continuous cathode current - drives standard optocouplers (e.g., PC817) directly without buffer stages |
Applications
| Rack Server Power | Industrial AC/DC |
|---|---|
|
Use Scenario: Secondary-side voltage sensing in isolated 48 V input telecom rectifiers with digital PMBus control. IC Role / Device Role / Timing Role: Programmable shunt reference providing precise feedback to PWM controller via optocoupler. Use Value: Enables ±0.5% output voltage accuracy across line/load/temperature, meeting IEEE 1621 Class A requirements. |
Use Scenario: Output voltage regulation in DIN-rail mounted 24 V/48 V industrial power supplies. IC Role / Device Role / Timing Role: Adjustable reference in TL494 or UC384x-based flyback feedback network. Use Value: Supports single-BOM design for multiple output voltages (12 V, 24 V, 48 V) via resistor reconfiguration. |
| AC Inverter Drives | Servo Drive Control |
|
Use Scenario: DC bus voltage monitoring and overvoltage protection in 3-phase VFDs with regenerative braking. IC Role / Device Role / Timing Role: Precision threshold detector feeding comparator input for fast shutdown logic. Use Value: 14 mV tempco ensures trip point stability across motor cabinet temperatures (−25°C to +70°C). |
Use Scenario: Isolated auxiliary supply regulation for gate drivers and position encoder interfaces in servo amplifiers. IC Role / Device Role / Timing Role: Shunt reference stabilizing 5 V or 3.3 V isolated bias rails derived from main DC bus. Use Value: 0.2 Ω dynamic impedance prevents output droop during high-frequency gate driver current pulses. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431CDBVR | SOT-23-3 package, C-grade (0°C–70°C), same 2.495 V ref but ±2% tolerance | Limited to commercial-temperature applications; lower thermal mass suits space-constrained PCBs | Select when board area is constrained and ambient temperature stays within 0°C–70°C |
| TL431BIDR | SOIC-8 package, I-grade (−40°C–85°C), B-grade (±0.5%) - identical spec but different orderable suffix | Same functional and thermal performance; differs only in tape-and-reel packaging and traceability | Preferred for volume production requiring full industrial qualification and TI's enhanced traceability |
Compared with TL431CDBVR, TL431CLPE3 offers extended temperature range and tighter tolerance; compared with TL431BIDR, it shares identical electrical specs but differs in packaging format and reel configuration-both alternatives require no schematic or layout changes.
Availability
TL431CLPE3 is available at Aetrix Electronics and suitable for rack server power, industrial AC/DC, and servo drive control applications requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.
Supply support for TL431CLPE3 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 heritage in precision reference design.
The TL431 product line was engineered for high-accuracy, low-drift voltage regulation in power supply feedback loops - targeting industrial, telecom, and computing applications where Zener diode limitations demanded improvement.
FAQ
What is the reference voltage tolerance of TL431CLPE3 at 25°C?
The TL431CLPE3 has a reference voltage tolerance of ±0.5% at 25°C, corresponding to the B-grade specification. This means its nominal 2.495 V reference falls between 2.483 V and 2.507 V under standard test conditions (VKA = Vref, IKA = 10 mA), ensuring high-precision feedback in regulated power supplies.
Does TL431CLPE3 support operation across industrial temperature ranges?
Yes, TL431CLPE3 is an I-grade device rated for operation from −40°C to +85°C. Its reference voltage deviation remains within 14 mV across this full range, making it suitable for demanding industrial environments such as factory automation controllers and motor drives where ambient temperature fluctuates widely.
What is the maximum cathode voltage rating for TL431CLPE3?
The absolute maximum cathode-to-anode voltage for TL431CLPE3 is 37 V, with recommended operating range up to 36 V. This allows safe integration into 24 V, 36 V, and 48 V industrial power systems, including DC bus monitoring and isolated flyback converter secondary-side regulation circuits.
Can TL431CLPE3 replace a Zener diode in power supply designs?
Yes, TL431CLPE3 is explicitly designed as a superior replacement for Zener diodes in voltage regulation applications. Its active output stage delivers sharper turn-on, lower dynamic impedance (0.2 Ω vs. typical Zener's >10 Ω), and programmable output (2.5 V–36 V), enabling higher accuracy and stability in feedback networks of linear and switching regulators.
What is the minimum cathode current required for regulation in TL431CLPE3?
The TL431CLPE3 requires a minimum cathode current of 0.4 mA to maintain regulation. This low Imin enables efficient operation in low-power auxiliary supplies and optocoupler-driven feedback loops where current budget is constrained, while still guaranteeing stable reference behavior across temperature and line variations.
TL431CLPE3 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- TO-226-3, TO-92-3 (TO-226AA)
- Series:
- -
- Packaging:
- Bulk
- 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:
- ±2.2%
- Temperature Coefficient:
- -
- Noise - 0.1Hz to 10Hz:
- -
- Noise - 10Hz to 10kHz:
- -
- Voltage - Input:
- -
- Current - Supply:
- -
- Current - Cathode:
- 1 mA
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TO-92-3
TL431CLPE3 FAQ
1.How can I place an order for TL431CLPE3 through Aetrix?
Please submit a Request for Quotation (RFQ) for TL431CLPE3 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 TL431CLPE3 reliable?
The price and inventory of TL431CLPE3 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL431CLPE3 is usually 5 days.
3.What payment methods are accepted for TL431CLPE3?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL431CLPE3 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TL431CLPE3?
TL431CLPE3 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TL431CLPE3 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 TL431CLPE3?
For technical support, including TL431CLPE3 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL431CLPE3 requirements.
6.How does Aetrix verify that TL431CLPE3 is sourced from the original manufacturer or authorized distributors?
All TL431CLPE3 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 TL431CLPE3 meets industry standards.
7.What is the process for return or replacement of TL431CLPE3?
All TL431CLPE3 units undergo pre-shipment inspection (PSI). If there is an issue with TL431CLPE3, 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 TL431CLPE3 part is unused and in its original packaging.
Return procedure for TL431CLPE3:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TL431CLPE3 Tags
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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
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AZ431LANTR-G1
Diodes Incorporated
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