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Texas Instruments TL431BQLPR
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- Part No.:
- TL431BQLPR
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- TO-226-3, TO-92-3 (TO-226AA) Formed Leads
- Datasheet:
-
TL431BQLPR.pdf
- Description:
- IC VREF SHUNT ADJ 0.5% TO92-3
- Quantity:
- Payment:
- Shipping:
Inventory:4,323
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Product details
Overview
TL431BQLPR from Texas Instruments is a precision programmable shunt voltage reference IC with 0.5% initial tolerance at 25°C, −40°C to +125°C operating temperature range (Q-grade), and 2.483–2.507 V reference voltage. It delivers 1 mA to 100 mA sink current, features 0.2 Ω typical dynamic impedance, and serves as a high-stability replacement for Zener diodes in feedback loops of isolated DC-DC converters.
For engineers reviewing the TL431BQLPR datasheet, TL431BQLPR pinout, TL431BQLPR application, or TL431BQLPR equivalent, this device is selected for automotive power supplies, industrial AC/DC adapters, and servo drive control modules where tight voltage accuracy and wide-temperature stability are critical.
Technical Context
The TL431BQLPR implements a three-terminal adjustable shunt regulator architecture with an internal error amplifier, reference, and output transistor. Its Q-grade rating confirms characterization across −40°C to +125°C, and its 14 mV max reference voltage deviation over that full range ensures stable closed-loop regulation in harsh thermal environments.
It operates as a two-resistor-programmable reference: the REF pin senses voltage relative to ANODE, triggering cathode current draw when input exceeds Vref. The sharp turn-on characteristic and low 0.2 Ω dynamic impedance enable fast transient response and minimal output ripple in switching power supply feedback paths.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reference Voltage | 2.483–2.507 V at 25°C - enables precise 2.5 V threshold setting with ±0.5% initial accuracy. |
| Initial Tolerance | ±0.5% (B grade) - reduces calibration overhead in production power supplies. |
| Temp Range | −40°C to +125°C (Q grade) - supports under-hood automotive and industrial motor drive applications. |
| Dynamic Impedance | 0.2 Ω typical - maintains stable regulation under fast load transients in SMPS feedback networks. |
| Sink Current Range | 1–100 mA - accommodates diverse optocoupler LED drive requirements in isolated flyback designs. |
| Ref Input Current | 2–4 µA - minimizes resistor-divider loading error in high-impedance voltage-setting networks. |
| Output Noise | Low - improves signal integrity in precision analog sensing and closed-loop control circuits. |
Pinout & Package
SOT-23-3 package (2.90 mm × 1.30 mm body size), surface-mount, lead-free, RoHS-compliant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1: Cathode | Shunt current output node | Connects to primary-side controller or optocoupler anode; sinks current to regulate output voltage. |
| Pin 2: Anode | Common reference ground | Typically tied to system ground or return path; defines reference potential for REF pin. |
| Pin 3: Ref | Threshold sense input | Monitors divided output voltage; triggers regulation when input exceeds Vref (≈2.5 V). |
Key Features
| Feature | Design Value |
|---|---|
| 0.5% Initial Accuracy (B Grade) | Reduces need for post-production trimming in cost-sensitive power supply designs. |
| −40°C to +125°C Operation (Q Grade) | Validated for automotive engine-control units and industrial inverters without derating. |
| 0.2 Ω Dynamic Impedance | Enables <10 mV output deviation during 50 mA step-load changes in feedback loops. |
| 1–100 mA Sink Capability | Directly drives standard PC817/PC817x optocouplers without external amplification. |
| Low Reference Input Current | 2–4 µA allows use of >100 kΩ divider resistors, minimizing standby power loss. |
Applications
| Rack Server Power | Industrial AC/DC Adapter |
|---|---|
Use Scenario: Secondary-side voltage regulation in 48 V input, 12 V/50 A isolated DC-DC modules. IC Role / Device Role / Timing Role: Shunt reference in optocoupler-coupled feedback loop controlling primary-side PWM duty cycle. Use Value: 0.5% reference accuracy ensures ±0.06 V output tolerance across line/load/temperature, meeting ATX12VO spec. |
Use Scenario: Output voltage stabilization in 230 VAC-input, 24 V/10 A industrial power supply. IC Role / Device Role / Timing Role: Precision voltage setpoint generator for TL494-based flyback controller feedback network. Use Value: Q-grade thermal stability prevents output drift beyond ±0.3% over −25°C to +70°C ambient cabinet operation. |
| Servo Drive Control Module | Notebook PC Power Adapter |
Use Scenario: Isolated auxiliary rail regulation (±15 V) for gate drivers and op-amps in 3-phase IGBT inverter stage. IC Role / Device Role / Timing Role: Dual-rail reference source via resistor-divider configuration, referenced to isolated ground. Use Value: Low 0.2 Ω impedance suppresses noise coupling into sensitive analog signal chains during high-dv/dt switching events. |
Use Scenario: Feedback reference in 19 V/3.42 A GaN-based USB-C PD adapter with active clamp flyback topology. IC Role / Device Role / Timing Role: High-accuracy shunt reference driving high-speed optocoupler for fast-loop bandwidth extension. Use Value: 2–4 µA input current enables ultra-low-power startup and light-load efficiency compliance with CoC Tier 2. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431BIDBVR | I-grade (−40°C to +85°C), same SOT-23-3 package and 0.5% tolerance, but lower max temp rating. | Suitable for commercial/industrial equipment without extended temperature requirements. | Select when ambient operating range stays ≤85°C and cost sensitivity outweighs automotive qualification needs. |
| TL431BQDBVR | Identical Q-grade rating and SOT-23-3 package; differs only in tape-and-reel packaging (DBVR vs QLPR). | No functional or performance difference; both meet same electrical and thermal specs. | Choose TL431BQDBVR for automated pick-and-place compatibility with standard 7" reel handling. |
Compared with TL431BIDBVR, TL431BQLPR adds guaranteed operation up to +125°C for under-hood or high-power density applications; compared with TL431BQDBVR, TL431BQLPR uses different packaging format but identical silicon and specifications.
Availability
TL431BQLPR is available at Aetrix Electronics and suitable for rack server power, industrial AC/DC adapters, and servo drive control modules requiring stable component supply across automotive and industrial temperature ranges.
Supply support for TL431BQLPR 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 designed for high-accuracy voltage regulation in isolated power supplies, battery chargers, and industrial control systems.
FAQ
What is the reference voltage tolerance of TL431BQLPR at 25°C?
The TL431BQLPR has a reference voltage tolerance of ±0.5% at 25°C, corresponding to a 2.483 V to 2.507 V range. This B-grade accuracy is specified in Section 6.13 of the TI SLVS543S datasheet and applies under recommended operating conditions with 10 mA cathode current. TL431BQLPR maintains this tolerance across its full −40°C to +125°C operating range with ≤34 mV total deviation.
Which package type does TL431BQLPR use?
TL431BQLPR uses the SOT-23-3 package (2.90 mm × 1.30 mm body size), confirmed by TI's orderable addendum and mechanical drawings in the SLVS543S datasheet. Pin 1 is Cathode, Pin 2 is Anode, and Pin 3 is Ref - matching the TL431BQxxx SOT-23-3 pinout, not the TL432 variant.
Does TL431BQLPR support operation at 125°C junction temperature?
TL431BQLPR is characterized for operation from −40°C to +125°C ambient (Q-grade), with a maximum junction temperature of 150°C per Absolute Maximum Ratings. Its electrical characteristics-including reference voltage deviation and dynamic impedance-are guaranteed across the full −40°C to +125°C range, making it suitable for high-temperature industrial and automotive under-hood applications.
What is the minimum cathode current required for regulation in TL431BQLPR?
The minimum cathode current for regulation in TL431BQLPR is 0.4 mA (typical) to 0.7 mA (max), as specified in Section 6.13 of the datasheet. This ensures reliable turn-on and stable feedback behavior even in ultra-low-power modes, such as light-load or standby conditions in AC/DC adapters.
How does TL431BQLPR differ from TL431BQDBVR?
TL431BQLPR and TL431BQDBVR share identical electrical specifications, thermal ratings (−40°C to +125°C), and SOT-23-3 package. The sole difference is packaging: TL431BQLPR uses a 13" tape-and-reel format (QLPR suffix), while TL431BQDBVR uses a 7" reel (DBVR suffix). Both are functionally interchangeable in circuit design.
TL431BQLPR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- TO-226-3, TO-92-3 (TO-226AA) Formed Leads
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- 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:
- ±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
TL431BQLPR FAQ
1.How can I place an order for TL431BQLPR through Aetrix?
Please submit a Request for Quotation (RFQ) for TL431BQLPR 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 TL431BQLPR reliable?
The price and inventory of TL431BQLPR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL431BQLPR is usually 5 days.
3.What payment methods are accepted for TL431BQLPR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL431BQLPR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TL431BQLPR?
TL431BQLPR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TL431BQLPR 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 TL431BQLPR?
For technical support, including TL431BQLPR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL431BQLPR requirements.
6.How does Aetrix verify that TL431BQLPR is sourced from the original manufacturer or authorized distributors?
All TL431BQLPR 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 TL431BQLPR meets industry standards.
7.What is the process for return or replacement of TL431BQLPR?
All TL431BQLPR units undergo pre-shipment inspection (PSI). If there is an issue with TL431BQLPR, 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 TL431BQLPR part is unused and in its original packaging.
Return procedure for TL431BQLPR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TL431BQLPR Tags
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LM4040CYM3-4.1-TR
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AZ431LBNTR-G1
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LM4041DIM3-ADJ/NOPB
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LM4040DIM3X-2.5/NOPB
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LM4040DIM3-2.5/NOPB
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AZ431LANTR-G1
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