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Texas Instruments TL431BQDBZRG4
- Part No.:
- TL431BQDBZRG4
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
TL431BQDBZRG4.pdf
- Description:
- IC VREF SHUNT ADJ 0.5% SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:3,567
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Product details
Overview
TL431BQDBZRG4 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, and 2.483–2.507 V typical VREF. It delivers 1–100 mA sink current capability with 0.2 Ω typical dynamic impedance and supports adjustable output from VREF to 36 V-used in feedback loops of isolated DC/DC converters and industrial power supplies.
For engineers reviewing the TL431BQDBZRG4 datasheet, TL431BQDBZRG4 pinout, TL431BQDBZRG4 application, or TL431BQDBZRG4 equivalent, key selection criteria include automotive-grade thermal stability (Q-temp), tight 0.5% VREF accuracy, low 14–34 mV total VREF drift over full temperature range, and SOT-23-3 footprint compatibility for space-constrained power regulation designs.
Technical Context
The TL431BQDBZRG4 implements a three-terminal adjustable shunt regulator architecture with an internal error amplifier, reference, and output transistor. Its sharp turn-on characteristic and active output stage enable Zener diode replacement in closed-loop feedback paths where precise voltage thresholding and stable regulation are required.
It operates as a two-input comparator: the REF pin senses voltage relative to ANODE, and the CATHODE sinks current when REF exceeds VREF. The Q-grade rating confirms qualification for automotive and extended-temperature industrial applications, with validated performance across −40°C to +125°C ambient conditions.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VREF tolerance | ±0.5% at 25°C - ensures high-accuracy feedback setpoint without external trimming |
| Operating temperature | −40°C to +125°C - qualified for under-hood automotive and industrial environments |
| VREF drift | 14–34 mV over full temperature range - guarantees stable regulation across thermal extremes |
| Dynamic impedance | 0.2 Ω typical - minimizes output voltage variation under load transients |
| Sink current range | 1 mA to 100 mA - supports direct drive of optocoupler LEDs or error amplifier inputs |
| Reference input current | 2–4 µA - enables high-impedance resistor-divider networks without significant loading error |
| Min cathode current | 0.4–0.7 mA - defines lowest usable current for stable regulation in low-power modes |
Pinout & Package
SOT-23-3 package (2.90 mm × 1.30 mm body size) with gull-wing leads; moisture sensitivity level (MSL) 1 per JEDEC J-STD-020.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1: REF | Reference input | High-impedance comparator input; sets regulation threshold via external resistor divider |
| Pin 2: CATHODE | Current-sink output | Active-low output node; sinks current to ANODE when REF > VREF |
| Pin 3: ANODE | Common return | Reference ground node; must be connected to system ground or return path of regulated supply |
Key Features
| Feature | Design Value |
|---|---|
| 0.5% VREF accuracy | Reduces need for post-production calibration in precision power supplies and battery management systems |
| Automotive Q-temp grade | Validated operation from −40°C to +125°C meets AEC-Q100 stress test requirements for under-hood use |
| 0.2 Ω dynamic impedance | Enables <10 mV output deviation during 50 mA load steps-critical for stable SMPS feedback |
| Adjustable 2.5–36 V output | Supports single-part design across multiple output voltages using only two external resistors |
| Low 2–4 µA reference current | Permits use of >1 MΩ resistor dividers, minimizing quiescent current in always-on circuits |
Applications
| AC Inverter Drive Feedback | Rack Server VRM Monitoring |
|---|---|
Use Scenario: Voltage sensing in three-phase motor control inverters for closed-loop speed/torque regulation. IC Role / Device Role / Timing Role: Shunt reference in isolated secondary-side feedback loop, setting precise threshold for optocoupler-driven primary controller. Use Value: 0.5% VREF tolerance and 14–34 mV total drift ensure consistent voltage setpoint across motor thermal cycling and ambient variations. |
Use Scenario: Output voltage monitoring and margining in multi-phase server VRMs powering CPUs/GPUs. IC Role / Device Role / Timing Role: Precision reference for analog-to-digital converter (ADC) input scaling and fault detection comparators. Use Value: Low 2–4 µA IREF avoids loading high-resistance sense networks, preserving ADC accuracy in dense PCB layouts. |
| Industrial AC/DC Adapter | Servo Drive Control Module |
Use Scenario: Secondary-side regulation in flyback-based industrial AC/DC adapters powering PLC I/O modules. IC Role / Device Role / Timing Role: Adjustable shunt reference controlling optocoupler LED current to regulate primary-side PWM duty cycle. Use Value: 1–100 mA sink capability directly drives common optocouplers (e.g., PC817, TLP185) without buffer transistors. |
Use Scenario: Current-sense amplifier reference and overvoltage protection threshold in servo motor driver power stages. IC Role / Device Role / Timing Role: Stable voltage reference for analog comparators detecting bus overvoltage events during regenerative braking. Use Value: 0.2 Ω dynamic impedance ensures fast response (<1 µs) to transient overvoltage, enabling reliable fault shutdown. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431BIDBZR | I-grade (−40°C to +85°C), same 0.5% VREF tolerance and SOT-23-3 package | Lacks automotive qualification; suitable for commercial/industrial equipment not requiring full Q-temp range | Select when ambient temperature stays ≤85°C and AEC-Q100 compliance is unnecessary |
| TLVH431BQDBZR | Lower 1.24 V reference voltage, same Q-temp grade and 0.5% tolerance, SOT-23-3 | Enables lower-voltage feedback loops (e.g., 1.8 V, 3.3 V rails); not interchangeable for 2.5 V+ setpoints | Choose for sub-2.5 V regulation where TL431BQDBZRG4's 2.483–2.507 V VREF is too high |
Compared with TL431BIDBZR and TLVH431BQDBZR, TL431BQDBZRG4 uniquely combines automotive Q-temp qualification, 2.5 V nominal reference, and 0.5% accuracy in SOT-23-3-making it the only option for high-precision, high-temperature feedback in automotive power modules and industrial drives.
Availability
TL431BQDBZRG4 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 extended temperature ranges and long production lifecycles.
Supply support for TL431BQDBZRG4 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 ICs, with decades of expertise in precision reference and power control technologies.
The TL431 product line delivers cost-effective, high-accuracy shunt references for feedback regulation in switching power supplies, battery chargers, and industrial control systems-designed for reliability across automotive, industrial, and computing applications.
FAQ
What is the reference voltage tolerance of TL431BQDBZRG4 at 25°C?
The TL431BQDBZRG4 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 standard test conditions (VKA = VREF, IKA = 10 mA). This B-grade accuracy is specified in Section 6.13 of the TI SLVS543S datasheet and applies exclusively to the Q-temp variant.
Does TL431BQDBZRG4 support operation beyond 100°C ambient temperature?
Yes, TL431BQDBZRG4 is rated for continuous operation from −40°C to +125°C ambient temperature (Q-grade), verified per TI's characterization data in Sections 6.7 and 6.13. Its thermal performance remains stable up to junction temperatures of 150°C, making it suitable for under-hood automotive and high-temperature industrial environments.
What is the minimum cathode current required for regulation in TL431BQDBZRG4?
The TL431BQDBZRG4 requires a minimum cathode current of 0.4 mA to maintain regulation, with a typical value of 0.7 mA across the full temperature range. This parameter (Imin) is defined in Section 6.13 of the datasheet and ensures stable operation even in low-power standby modes of power supplies.
Can TL431BQDBZRG4 replace a Zener diode in feedback circuits?
Yes, TL431BQDBZRG4 is explicitly designed as a precision replacement for Zener diodes in feedback circuits. Its active output stage provides sharper turn-on, lower dynamic impedance (0.2 Ω vs. typical Zener's 5–20 Ω), and tighter voltage tolerance-enabling improved regulation accuracy and transient response in SMPS and linear regulators.
What is the dynamic impedance specification for TL431BQDBZRG4?
The TL431BQDBZRG4 has a typical dynamic impedance of 0.2 Ω, measured at f ≤ 1 kHz with cathode current ranging from 1 mA to 100 mA. This low impedance minimizes output voltage variation during load transients and is confirmed in Sections 6.5–6.13 of the TI SLVS543S datasheet for all Q-grade variants.
TL431BQDBZRG4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Discontinued at Digi-Key
- 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:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
TL431BQDBZRG4 FAQ
1.How can I place an order for TL431BQDBZRG4 through Aetrix?
Please submit a Request for Quotation (RFQ) for TL431BQDBZRG4 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 TL431BQDBZRG4 reliable?
The price and inventory of TL431BQDBZRG4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL431BQDBZRG4 is usually 5 days.
3.What payment methods are accepted for TL431BQDBZRG4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL431BQDBZRG4 transactions.
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4.How is shipping managed for TL431BQDBZRG4?
TL431BQDBZRG4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TL431BQDBZRG4 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 TL431BQDBZRG4?
For technical support, including TL431BQDBZRG4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL431BQDBZRG4 requirements.
6.How does Aetrix verify that TL431BQDBZRG4 is sourced from the original manufacturer or authorized distributors?
All TL431BQDBZRG4 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 TL431BQDBZRG4 meets industry standards.
7.What is the process for return or replacement of TL431BQDBZRG4?
All TL431BQDBZRG4 units undergo pre-shipment inspection (PSI). If there is an issue with TL431BQDBZRG4, 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 TL431BQDBZRG4 part is unused and in its original packaging.
Return procedure for TL431BQDBZRG4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TL431BQDBZRG4 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
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LM4040EIM3-2.5/NOPB
Texas Instruments
-
AZ431LBNTR-G1
Diodes Incorporated
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LM4040D20IDBZR
Texas Instruments
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LM4041DIM3-ADJ/NOPB
Texas Instruments
-
LM4040DIM3X-2.5/NOPB
Texas Instruments
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LM4040DIM3-2.5/NOPB
Texas Instruments
-
AZ431LANTR-G1
Diodes Incorporated
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