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Texas Instruments TL431BQLPME3
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- Part No.:
- TL431BQLPME3
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- TO-226-3, TO-92-3 (TO-226AA) Formed Leads
- Datasheet:
-
TL431BQLPME3.pdf
- Description:
- IC VREF SHUNT ADJ 0.5% TO92-3
- Quantity:
- Payment:
- Shipping:
Inventory:6,867
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Product details
Overview
TL431BQLPME3 from Texas Instruments is a precision programmable shunt voltage reference in SOT-23-3 package, featuring 0.5% initial reference voltage tolerance at 25°C, −40°C to +125°C operating temperature range (Q-grade), and 0.2Ω typical dynamic impedance. It replaces Zener diodes in feedback loops of isolated DC/DC converters and industrial power supplies.
For engineers reviewing the TL431BQLPME3 datasheet, TL431BQLPME3 pinout, TL431BQLPME3 application, or TL431BQLPME3 equivalent, key selection criteria include reference accuracy over automotive temperature range, cathode current sink capability (1–100 mA), low output noise, and stability with capacitive loads up to 1 µF.
Technical Context
The TL431BQLPME3 implements an internal error amplifier with adjustable reference threshold (VREF = 2.483–2.507 V) and sharp turn-on characteristic, enabling precise regulation via external resistor divider. Its active output stage provides high gain and low output impedance for stable closed-loop control.
Designed for Q-grade (−40°C to +125°C) operation, it delivers ≤34 mV total reference voltage deviation across temperature and maintains <2.5 µA reference input current drift - critical for high-accuracy feedback in rack server PSUs and servo drive controllers.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reference Voltage (VREF) | 2.483–2.507 V at 25°C; enables accurate 2.5 V setpoint with ±0.5% initial tolerance |
| Initial Accuracy | ±0.5% (B grade); reduces calibration burden in production test for industrial power modules |
| Temp Range | −40°C to +125°C (Q grade); supports under-hood automotive and industrial motor drive applications |
| Dynamic Impedance | 0.2 Ω typical; ensures minimal output voltage shift under load transients in switching regulator feedback paths |
| Cathode Current | 1–100 mA sink capability; accommodates wide range of optocoupler LED drive and error amplifier bias currents |
| Ref Input Current | 2–4 µA typical; allows use of high-value feedback resistors (>1 MΩ) to minimize power loss |
| Output Noise | Low broadband noise; improves regulation stability in noise-sensitive analog feedback 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 | Connects to primary-side feedback network; sinks current to regulate output voltage |
| Pin 2 (REF) | Reference input threshold | Compares divided output voltage against internal 2.5 V bandgap; sets regulation point |
| Pin 3 (ANODE) | Common return path | Typically tied to system ground or secondary-side common; defines voltage reference plane |
Key Features
| Feature | Design Value |
|---|---|
| 0.5% reference accuracy | Reduces need for post-production trimming in high-volume AC/DC adapter designs |
| 0.2 Ω dynamic impedance | Minimizes output voltage droop during fast load steps in servo drive power stages |
| −40°C to +125°C operation | Enables deployment in engine-control units and industrial inverters without derating |
| 1–100 mA cathode sink | Directly drives standard optocouplers (e.g., PC817) without external transistor buffering |
| Low reference input current | Permits >100 kΩ feedback dividers, reducing standby power in energy-efficient adapters |
Applications
| Rack Server Power | Industrial AC/DC Converter |
|---|---|
Use Scenario: Secondary-side voltage regulation in 1U server PSUs with digital PMBus control. IC Role / Device Role / Timing Role: Precision shunt reference in optocoupler feedback loop for isolated 12 V/54 A output. Use Value: 0.5% VREF tolerance ensures ±0.5% output regulation across line/load/temperature - meeting Intel VR13 specs. | Use Scenario: Output voltage sensing in DIN-rail mounted 24 V/20 A industrial power supply. IC Role / Device Role / Timing Role: Adjustable shunt regulator setting feedback threshold for UC384x-based flyback controller. Use Value: Q-grade temperature range guarantees stable regulation from cold warehouse startup to hot factory-floor operation. |
| AC Inverter Drive | Servo Drive Control Module |
Use Scenario: DC bus voltage monitoring and overvoltage protection in 3-phase VFDs. IC Role / Device Role / Timing Role: Reference input for comparator detecting >800 V DC bus fault condition. Use Value: Low 2–4 µA reference current enables high-impedance voltage divider, minimizing power dissipation in high-voltage sense networks. | Use Scenario: Isolated feedback for auxiliary 15 V bias rail powering gate drivers in servo amplifier PCB. IC Role / Device Role / Timing Role: Shunt reference in TL431+optocoupler loop regulating isolated auxiliary supply. Use Value: 0.2 Ω dynamic impedance prevents oscillation with 100 nF optocoupler CTR capacitor, ensuring stable transient response. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431BQDBVR | SOT-23-3 package, same BQ grade specs, identical pinout and electrical behavior | No functional difference; differs only in tape-and-reel packaging and reel size | Select TL431BQDBVR for automated SMT placement requiring different carrier tape configuration |
| TLVH431BQDBVR | Lower 1.24 V reference voltage, 1.5% initial accuracy, same Q-temp range and SOT-23-3 package | Used where lower reference voltage enables higher output voltage with same resistor values or reduced divider power | Choose TLVH431BQDBVR when designing 3.3 V or 5 V outputs with tighter resistor ratio constraints |
Compared with TL431BQLPME3, TL431BQDBVR offers identical performance in alternate packaging, while TLVH431BQDBVR trades reference voltage and accuracy for design flexibility in low-output-voltage systems - neither is pin-compatible with TL431BQLPME3 in function-critical feedback paths requiring 2.5 V threshold.
Availability
TL431BQLPME3 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 long production lifecycles.
Supply support for TL431BQLPME3 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 power management and precision analog ICs.
The TL431 product line delivers programmable shunt references for feedback regulation in isolated power supplies, designed specifically for high-accuracy, high-reliability industrial and automotive power systems.
FAQ
What is the reference voltage tolerance of TL431BQLPME3 at 25°C?
The TL431BQLPME3 has a reference voltage tolerance of ±0.5% at 25°C, corresponding to a VREF range of 2.483 V to 2.507 V under specified test conditions (VKA = VREF, IKA = 10 mA). This B-grade accuracy is confirmed in Section 6.13 of the TI SLVS543S datasheet and applies specifically to the TL431BQ variant in SOT-23-3 packaging.
Does TL431BQLPME3 support operation across the full automotive temperature range?
Yes, TL431BQLPME3 is rated for −40°C to +125°C operation (Q-grade), validated per TI's characterization data in Sections 6.7 and 6.13. Its reference voltage deviation remains ≤34 mV across this range, making it suitable for under-hood and industrial environments where thermal stability is critical - unlike C-grade (0°C–70°C) or I-grade (−40°C–85°C) variants.
What is the cathode current capability of TL431BQLPME3?
The TL431BQLPME3 supports continuous cathode current from 1 mA to 100 mA, with minimum regulation current of 0.4–0.7 mA depending on temperature. This sink capability allows direct interfacing with standard optocoupler LEDs (e.g., PC817, SFH615A) without external buffering, as verified in TI's recommended operating conditions (Section 6.4) and electrical characteristics tables.
How does the dynamic impedance of TL431BQLPME3 affect power supply stability?
TL431BQLPME3 exhibits 0.2 Ω typical dynamic impedance (|ZKA|) at frequencies ≤1 kHz and cathode currents from 1–100 mA. This low value minimizes output voltage perturbation during load transients and improves phase margin in optocoupler-based feedback loops - directly supporting stable regulation in flyback and forward converters per Figure 6-12 and stability boundary analysis in Figures 6-18–6-19.
Is TL431BQLPME3 pin-compatible with other TL431 variants in SOT-23-3?
Yes, TL431BQLPME3 uses the standard TL431 SOT-23-3 pinout (Pin 1 = CATHODE, Pin 2 = REF, Pin 3 = ANODE), matching all TL431x variants in DBZ package including TL431C, TL431I, and other B-grade versions. Pin compatibility is confirmed in Table 5-1 and Figure 5-1 of the TI datasheet, enabling drop-in replacement within the same grade and package family.
TL431BQLPME3 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- TO-226-3, TO-92-3 (TO-226AA) Formed Leads
- Series:
- -
- Packaging:
- Cut Tape (CT)
- 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:
- ±0.5%
- 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:
- Through Hole
- Supplier Device Package:
- TO-92-3
TL431BQLPME3 FAQ
1.How can I place an order for TL431BQLPME3 through Aetrix?
Please submit a Request for Quotation (RFQ) for TL431BQLPME3 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 TL431BQLPME3 reliable?
The price and inventory of TL431BQLPME3 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL431BQLPME3 is usually 5 days.
3.What payment methods are accepted for TL431BQLPME3?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL431BQLPME3 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TL431BQLPME3?
TL431BQLPME3 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TL431BQLPME3 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 TL431BQLPME3?
For technical support, including TL431BQLPME3 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL431BQLPME3 requirements.
6.How does Aetrix verify that TL431BQLPME3 is sourced from the original manufacturer or authorized distributors?
All TL431BQLPME3 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 TL431BQLPME3 meets industry standards.
7.What is the process for return or replacement of TL431BQLPME3?
All TL431BQLPME3 units undergo pre-shipment inspection (PSI). If there is an issue with TL431BQLPME3, 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 TL431BQLPME3 part is unused and in its original packaging.
Return procedure for TL431BQLPME3:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TL431BQLPME3 Tags
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TL431AIDBZR
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AZ431LBNTR-G1
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LM4040D20IDBZR
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LM4041DIM3-ADJ/NOPB
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LM4040DIM3X-2.5/NOPB
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AZ431LANTR-G1
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