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Nexperia USA Inc. TL431BCDBZR-QR
- Part No.:
- TL431BCDBZR-QR
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Voltage Reference
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
TL431BCDBZR-QR.pdf
- Description:
- IC VREF SHUNT 2.495V SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:2,936
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Product details
Overview
TL431BCDBZR-Q from Nexperia is a B-grade (±0.5 %) adjustable precision shunt regulator in SOT23 package, delivering 2.495 V reference voltage with 0.2 Ω dynamic cathode-anode impedance and 1–100 mA sink current capability. It operates across –40 °C to 125 °C, qualified per AEC-Q100 Grade 1, and serves as the error amplifier and voltage reference in isolated SMPS feedback loops.
For engineers reviewing the TL431BCDBZR-Q datasheet, TL431BCDBZR-Q pinout, TL431BCDBZR-Q application, or TL431BCDBZR-Q equivalent, this page delivers verified electrical specs, automotive-grade thermal derating curves, SOT23 terminal mapping, and real-world use cases in precision current sinking and programmable shunt regulation.
Technical Context
The TL431BCDBZR-Q implements a bandgap-referenced op-amp with internal NPN output stage, configured as a 3-terminal shunt regulator where cathode-anode voltage is set by external resistor dividers between 2.495 V and 36 V. Its 0.5 % reference tolerance and 9 mV typical temperature drift over 0–70 °C enable high-accuracy closed-loop control.
It features low 2–4 μA reference input current, <0.5 μA off-state leakage at 36 V, and stable operation up to 100 nF load capacitance without oscillation-critical for noise-sensitive feedback paths in automotive DC/DC converters and battery management systems.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reference Voltage (Vref) | 2483–2507 mV at 10 mA cathode current; enables ±0.5 % output regulation accuracy in programmable supplies |
| Cathode Current Range | 1–100 mA; supports direct sinking of error amplifier output in SMPS controllers without external transistor |
| Dynamic Impedance (ZKA) | 0.2–0.5 Ω below 1 kHz; ensures minimal AC perturbation on reference node during transient load steps |
| Reference Input Current | 2–4 μA typical; allows high-value resistor dividers (>1 MΩ) to minimize quiescent power in always-on circuits |
| Temperature Range | –40 °C to +125 °C; validated for under-hood automotive applications per AEC-Q100 Grade 1 |
| ESD Rating | 4 kV HBM; provides robustness against handling and board-level electrostatic discharge events |
| Output Noise | Low-noise design confirmed via <10 μV RMS measurement; suitable for precision analog sensing interfaces |
Pinout & Package
SOT23-3 plastic surface-mounted package (3.0 × 1.4 × 1.1 mm), standard pinning configuration per Table 3: Pin 1 = Cathode (K), Pin 2 = Reference (REF), Pin 3 = Anode (A).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 - K (Cathode) | Sink output terminal | Connects to regulated rail or SMPS optocoupler LED anode; carries full error current up to 100 mA |
| 2 - REF (Reference) | High-impedance input | Compares divided output voltage against internal 2.495 V bandgap; draws only 2–4 μA for bias |
| 3 - A (Anode) | Return path | Connected to system ground or low-side return; completes shunt current path through external resistors |
Key Features
| Feature | Design Value |
|---|---|
| Programmable Output Voltage | 2.495 V to 36 V via two external resistors; eliminates need for multiple fixed-voltage references |
| B-Grade Precision | ±0.5 % reference tolerance at 25 °C; reduces calibration overhead in automotive sensor supply rails |
| Automotive Qualification | AEC-Q100 Grade 1 qualified; validated for 15-year lifetime in engine control units and ADAS power domains |
| Low Dynamic Impedance | 0.2 Ω typical; maintains tight regulation during fast load transients in buck converter feedback networks |
| Stable with Capacitive Loads | No oscillation up to 100 nF; simplifies layout in isolated flyback designs without added compensation components |
Applications
| Shunt Regulator | Precision Current Sink |
|---|---|
|
Use Scenario: Stabilizing 5 V or 12 V auxiliary rail in automotive body control module using resistor divider and local bypass cap. IC Role / Device Role / Timing Role: Shunt regulator providing precise voltage reference and error correction via cathode current modulation. Use Value: Replaces discrete Zener + transistor combo with 5× smaller footprint and ±0.5 % initial accuracy over full temperature range. |
Use Scenario: Setting constant 20 mA LED drive current in adaptive headlight control unit. IC Role / Device Role / Timing Role: Precision current sink where REF pin senses voltage drop across sense resistor. Use Value: Delivers <±1 % current accuracy across –40 °C to +125 °C without trimming or calibration. |
| Isolated SMPS Feedback | Programmable Threshold Detector |
|
Use Scenario: Secondary-side voltage sensing in 48 V–12 V isolated DC/DC converter for electric power steering. IC Role / Device Role / Timing Role: Error amplifier in optocoupler-coupled feedback loop, comparing output to internal 2.495 V reference. Use Value: Enables <±1 % output regulation with <10 μs response time to line/load transients, meeting ASIL-B functional safety requirements. |
Use Scenario: Overvoltage detection on 24 V battery rail triggering shutdown when voltage exceeds 27.5 V. IC Role / Device Role / Timing Role: Adjustable comparator with temperature-compensated threshold set by resistor divider on REF pin. Use Value: Provides stable trip point with <±0.2 V variation over –40 °C to +125 °C, eliminating thermistor-based compensation. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar adjustable shunt regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431BIDBZR-Q | Mirrored pinout (REF-K-A vs. K-REF-A); identical electrical specs and AEC-Q100 qualification | Requires PCB layout revision due to swapped REF/K pins; not drop-in compatible | Select only if redesigning board to accommodate mirrored SOT23 footprint |
| TL431ACDBZR-Q | 1 % reference tolerance (vs. 0.5 %); otherwise identical pinout, temp range, and sink current | Suitable for non-safety-critical consumer power supplies where tighter tolerance is unnecessary | Choose for cost-sensitive designs where ±1 % regulation meets system spec and AEC-Q100 is not required |
Compared with TL431BCDBZR-Q, TL431BIDBZR-Q demands layout changes but matches all performance metrics, while TL431ACDBZR-Q trades 0.5 % tolerance for lower cost in less demanding applications-neither offers improved thermal stability or wider operating range.
Availability
TL431BCDBZR-Q is available at Aetrix Electronics and suitable for automotive power conversion, precision current sourcing, and isolated feedback loop design requiring stable component supply across extended temperature ranges and long product lifecycles.
Supply support for TL431BCDBZR-Q 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
Nexperia is a global semiconductor expert focused on high-volume, high-reliability logic, discrete, and MOSFET solutions, with deep expertise in automotive-qualified analog components.
The TL431-Q family targets automotive and industrial power management applications, delivering AEC-Q100 qualified shunt regulators optimized for precision, thermal stability, and long-term reliability in harsh environments.
FAQ
What is the maximum cathode-anode voltage for TL431BCDBZR-Q?
The absolute maximum cathode-anode voltage is 37 V per IEC 60134 limiting values. Recommended operating range is 2.495 V to 36 V. Exceeding 37 V risks permanent junction damage, even momentarily. Derating applies above 25 °C ambient per Figure 2's ceramic PCB curve (132 K/W).
Can TL431BCDBZR-Q replace a Zener diode directly?
Yes-it functions as a 2.495 V Zener with programmable breakdown voltage up to 36 V using two external resistors. Unlike passive Zeners, it provides sharp turn-on, low dynamic impedance (0.2 Ω), and stable reference current (2–4 μA), enabling higher accuracy and lower power loss in regulation circuits.
Does TL431BCDBZR-Q require an input capacitor?
No input capacitor is required, but a 100 pF capacitor at the REF pin is recommended per Figure 26 to suppress switching noise coupling from primary-side SMPS circuits. Larger capacitors (>1 nF) may cause instability; layout best practice is short traces and local decoupling at cathode.
How does the B-grade tolerance affect system calibration?
The ±0.5 % Vref tolerance at 25 °C reduces or eliminates factory calibration steps in automotive modules. Combined with <±17 mV drift over –40 °C to +125 °C, it enables single-point calibration at room temperature while maintaining <±1.2 % total output error across full operating range.
TL431BCDBZR-QR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- 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:
- 600 µA
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- Automotive
- Qualification:
- AEC-Q100
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3 (TO-236)
TL431BCDBZR-QR FAQ
1.How can I place an order for TL431BCDBZR-QR through Aetrix?
Please submit a Request for Quotation (RFQ) for TL431BCDBZR-QR 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 TL431BCDBZR-QR reliable?
The price and inventory of TL431BCDBZR-QR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL431BCDBZR-QR is usually 5 days.
3.What payment methods are accepted for TL431BCDBZR-QR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL431BCDBZR-QR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TL431BCDBZR-QR?
TL431BCDBZR-QR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TL431BCDBZR-QR 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 TL431BCDBZR-QR?
For technical support, including TL431BCDBZR-QR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL431BCDBZR-QR requirements.
6.How does Aetrix verify that TL431BCDBZR-QR is sourced from the original manufacturer or authorized distributors?
All TL431BCDBZR-QR 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 TL431BCDBZR-QR meets industry standards.
7.What is the process for return or replacement of TL431BCDBZR-QR?
All TL431BCDBZR-QR units undergo pre-shipment inspection (PSI). If there is an issue with TL431BCDBZR-QR, 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 TL431BCDBZR-QR part is unused and in its original packaging.
Return procedure for TL431BCDBZR-QR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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