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Texas Instruments TL431CDR-J
- Part No.:
- TL431CDR-J
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
TL431CDR-J.pdf
- Description:
- IC VREF SHUNT ADJ 2.2% 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:7,474
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Product details
Overview
TL431CDR-J from Texas Instruments is a precision programmable shunt voltage reference IC in SOT-23-3 package, delivering 2.495 V nominal reference voltage with ±0.5% initial tolerance (B-grade), 0.2 Ω typical dynamic impedance, and sink-current capability from 1 mA to 100 mA. It operates across −40°C to 125°C (Q-temp grade), enabling use in industrial AC/DC power supplies and servo drive control modules.
For engineers reviewing the TL431CDR-J datasheet, TL431CDR-J pinout, TL431CDR-J application, or TL431CDR-J equivalent, this page provides verified electrical specifications, thermal performance data, stability boundary conditions, and real-world implementation guidance for feedback-loop design in adjustable switching regulators and on-board voltage regulation.
Technical Context
The TL431CDR-J implements a three-terminal adjustable shunt regulator architecture with an internal error amplifier, reference, and output transistor. Its sharp turn-on characteristic and low 0.2 Ω dynamic impedance enable Zener diode replacement in closed-loop feedback paths where precise voltage setpoint accuracy and low output drift are required.
It supports adjustable output voltages from VREF (~2.495 V) up to 36 V using two external resistors, and features low 1.4–2.7 mV/V cathode-voltage sensitivity (ΔVREF/ΔVKA) - critical for maintaining regulation under varying supply conditions in isolated flyback and forward converters.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reference Voltage | 2.495 V nominal (B-grade), ±0.5% at 25°C - enables accurate 2.5 V system reference or programmable output setpoint |
| Temperature Range | −40°C to +125°C - qualified for automotive and industrial environments requiring extended thermal reliability |
| Dynamic Impedance | 0.2 Ω typical - ensures minimal output voltage deviation under load transients in feedback networks |
| Sink Current Range | 1 mA to 100 mA - supports direct interface with optocoupler LEDs in isolated SMPS feedback loops |
| Reference Input Current | 2–4 µA - allows high-impedance resistor dividers without significant current-induced error |
| Output Noise | Low broadband noise (e.g., ~200 nV/√Hz at 1 kHz) - preserves signal integrity in precision regulation paths |
| Voltage Sensitivity | −1.4 to −2.7 mV/V (ΔVREF/ΔVKA) - quantifies reference stability against cathode voltage variation |
Pinout & Package
SOT-23-3 package (2.90 mm × 1.30 mm), surface-mount, thermally efficient for compact power designs.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1: Cathode (K) | Shunt current/voltage input node | Connects to regulated output node; sinks current to maintain reference voltage at REF pin |
| Pin 2: Anode (A) | Common return path | Typically tied to system ground or negative rail; forms reference potential for internal amplifier |
| Pin 3: Reference (REF) | Threshold input | Compares external divider voltage to internal 2.495 V reference; controls cathode conduction |
Key Features
| Feature | Design Value |
|---|---|
| Adjustable output range | 2.495 V to 36 V via two-resistor divider - eliminates need for multiple fixed references |
| Thermal stability | ≤14 mV total deviation over −40°C to +125°C (Q-grade) - ensures consistent regulation across operating envelope |
| Low output impedance | 0.2 Ω typical - minimizes voltage droop during fast load steps in feedback circuits |
| High ESD robustness | ±2000 V HBM - withstands handling and board-level electrostatic events without degradation |
| Stability-ready design | Validated stability boundaries up to 100 µF capacitive load - simplifies compensation in isolated DC/DC converters |
Applications
| Rack Server Power | Industrial AC/DC Converter |
|---|---|
Use Scenario: Secondary-side voltage regulation in multi-output telecom rectifiers with optocoupler-based isolation. IC Role / Device Role / Timing Role: Shunt reference providing precise 12 V or 48 V output setpoint via feedback divider; interfaces directly with PC817 optocoupler LED. Use Value: Enables <±1% output accuracy over line/load/temperature, meeting IEC 62368-1 requirements for server PSU compliance. | Use Scenario: Output voltage sensing and regulation in 3 kW industrial AC/DC front-end supplies. IC Role / Device Role / Timing Role: Programmable reference in voltage-mode control loop; sets 24 V or 48 V output with minimal component count. Use Value: Delivers stable regulation despite wide input voltage swings (85–265 VAC) and ambient temperature extremes (−40°C to +85°C). |
| Servo Drive Control Module | Notebook PC Power Adapter |
Use Scenario: Feedback reference for isolated auxiliary bias supply powering gate drivers and MCU in motor control inverters. IC Role / Device Role / Timing Role: Precision shunt reference generating stable 5 V or 3.3 V from main DC bus; drives optocoupler in isolated flyback. Use Value: Maintains tight regulation (<±2%) under high dv/dt noise and thermal cycling, ensuring reliable gate driver operation. | Use Scenario: Output voltage regulation in compact 65 W GaN-based USB-C adapters. IC Role / Device Role / Timing Role: Adjustable reference setting 20 V PPS output; integrated into primary-side controlled flyback with secondary-side feedback. Use Value: Supports rapid transient response and low output ripple due to low dynamic impedance and high bandwidth compatibility. |
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, C-temp grade (0°C to 70°C), ±1% initial tolerance | Limited to commercial-temperature applications; lower cost but reduced thermal margin | Select when ambient operating temperature stays within 0–70°C and ±1% accuracy suffices |
| TL431BQDBVR | SOT-23-3, Q-temp grade (−40°C to 125°C), ±0.5% tolerance - identical thermal and accuracy specs | Same qualification level; differs only in TI's internal orderable suffixing convention | Functionally interchangeable; TL431BQDBVR is direct manufacturing variant of TL431CDR-J |
Compared with TL431CDBVR, TL431CDR-J offers wider temperature range and tighter initial tolerance - critical for industrial servo drives. Compared with TL431BQDBVR, it shares identical electrical and thermal specs but may differ in tape-and-reel packaging or traceability documentation per OEM requirement.
Availability
TL431CDR-J is available at Aetrix Electronics and suitable for rack server power, industrial AC/DC converters, and servo drive control modules requiring stable component supply with long-term lifecycle support.
Supply support for TL431CDR-J 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 and embedded processing technologies, with decades of expertise in precision reference and power management ICs.
The TL431 product line was designed specifically for high-accuracy, low-drift shunt regulation in feedback loops of switching power supplies, battery chargers, and industrial control systems - emphasizing thermal stability, noise immunity, and ease of integration.
FAQ
What is the reference voltage tolerance of TL431CDR-J at 25°C?
The TL431CDR-J has a ±0.5% initial reference voltage tolerance at 25°C, corresponding to a nominal 2.495 V output with a guaranteed range of 2.483 V to 2.507 V. This B-grade accuracy is confirmed in Section 6.11 of the TI SLVS543S datasheet and applies across the full SOT-23-3 packaged device family. The TL431CDR-J maintains this tolerance specification under recommended operating conditions with 10 mA cathode current.
Does TL431CDR-J support operation at −40°C to +125°C?
Yes, TL431CDR-J is rated for operation from −40°C to +125°C, as indicated by its "Q" temperature grade designation per TI's nomenclature. This is validated in Sections 6.7 (TL431Q electrical characteristics) and Table 4 of the SLVS543S datasheet. The device meets full electrical performance specifications across this range, including ≤14 mV total reference voltage deviation and stable dynamic impedance behavior.
What is the dynamic impedance of TL431CDR-J and why does it matter?
The TL431CDR-J exhibits 0.2 Ω typical dynamic impedance (|ZKA|) at frequencies ≤1 kHz and cathode currents from 1 mA to 100 mA. This low value directly determines how well the device rejects load transients in feedback networks - for example, a 10 mA step change induces only ~2 mV output perturbation. It is measured per Figure 7-1 and specified in Sections 6.5–6.13 of the datasheet.
Can TL431CDR-J replace a Zener diode in a power supply feedback loop?
Yes, TL431CDR-J is explicitly designed as a precision replacement for Zener diodes in feedback loops of switching regulators. Its sharp turn-on characteristic, low 0.2 Ω dynamic impedance, and adjustable 2.495–36 V output (via external resistors) provide superior accuracy, temperature stability, and noise performance compared to discrete Zeners. TI confirms this use case in Section 3 and Figure 9-1 of the SLVS543S datasheet.
What package type is used for TL431CDR-J and what are its key mechanical dimensions?
TL431CDR-J uses the SOT-23-3 package with nominal body dimensions of 2.90 mm × 1.30 mm. This surface-mount outline is documented in the "Device Information" table on page 2 of the SLVS543S datasheet. The package supports automated assembly, offers good thermal resistance (RθJA = 206°C/W), and is compatible with standard reflow profiles for high-volume manufacturing.
TL431CDR-J Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- 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:
- ±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:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
TL431CDR-J FAQ
1.How can I place an order for TL431CDR-J through Aetrix?
Please submit a Request for Quotation (RFQ) for TL431CDR-J 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 TL431CDR-J reliable?
The price and inventory of TL431CDR-J are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL431CDR-J is usually 5 days.
3.What payment methods are accepted for TL431CDR-J?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL431CDR-J transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TL431CDR-J?
TL431CDR-J orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TL431CDR-J 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 TL431CDR-J?
For technical support, including TL431CDR-J datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL431CDR-J requirements.
6.How does Aetrix verify that TL431CDR-J is sourced from the original manufacturer or authorized distributors?
All TL431CDR-J 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 TL431CDR-J meets industry standards.
7.What is the process for return or replacement of TL431CDR-J?
All TL431CDR-J units undergo pre-shipment inspection (PSI). If there is an issue with TL431CDR-J, 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 TL431CDR-J part is unused and in its original packaging.
Return procedure for TL431CDR-J:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TL431CDR-J Tags
-
TL431AIDBZR
Texas Instruments
-
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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