My Inquiry
My Account
Diodes Incorporated ZTL431BQFTA
- Part No.:
- ZTL431BQFTA
- Manufacturer:
- Diodes Incorporated
- Category:
- Voltage Reference
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
ZTL431BQFTA.pdf
- Description:
- IC VREF SHUNT 2.5V SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:705
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
ZTL431BQFTA from Diodes Incorporated is an automotive-grade adjustable precision shunt regulator in SOT23 package, featuring 0.5% initial reference voltage tolerance (2.5 V), -40°C to +125°C operating range, 0.2 Ω typical dynamic output impedance, and 1–100 mA sink current capability. It functions as a programmable voltage reference in feedback loops for isolated power supplies and linear regulators.
For engineers reviewing the ZTL431BQFTA datasheet, ZTL431BQFTA pinout, ZTL431BQFTA application, or ZTL431BQFTA equivalent, this device supports AEC-Q100-compliant designs requiring stable 2.5 V reference with low temperature drift, high sink current headroom, and robust stability under capacitive loads up to 4.7 nF.
Technical Context
The ZTL431BQFTA implements a bandgap-based reference core with internal error amplifier and NPN output stage, enabling precise regulation via external resistor divider. Its architecture supports stable operation across 2.5 V to 20 V output programming range while maintaining <34 mV reference deviation over -40°C to +125°C.
It features a dedicated cathode-anode-reference terminal configuration optimized for optocoupler feedback in flyback converters and overvoltage protection circuits. The device's 2 kV HBM ESD rating and IATF 16949 manufacturing ensure suitability for automotive powertrain and body electronics.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reference Voltage (VREF) | 2.5 V ±0.5% at +25°C - enables accurate setpoint control for feedback networks |
| Temp Range | -40°C to +125°C - qualified for under-hood automotive applications |
| Sink Current Range | 1 mA to 100 mA - supports direct drive of optocoupler LEDs and higher-power shunt loads |
| Dynamic Output Impedance | 0.2 Ω typical - ensures minimal output voltage shift under load transients |
| Cathode Voltage Max | 20 V - allows use in 12 V and 24 V automotive systems with margin |
| Ref Input Current | 2–4 µA - reduces divider resistor power loss and thermal drift impact |
| Stability Capacitance | ≥4.7 nF anode-to-cathode - prevents oscillation in closed-loop configurations |
Pinout & Package
Package: SOT23 (3-pin, surface-mount). Compact footprint (2.4 mm × 1.3 mm) with matte tin-plated leads, moisture sensitivity level 1, and 0.009 g mass.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1 (Anode) | Anode connection | Return path for cathode current; tied to system ground or low-side reference point |
| Pin 2 (Cathode) | Cathode output | Current-sinking output node; connects to supply rail or optocoupler anode |
| Pin 3 (Ref) | Reference input | High-impedance sense node for external resistor divider; sets regulated output voltage |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q100 Grade 1 qualification | Validated for automotive ambient temperatures (-40°C to +125°C) and PPAP-capable production |
| 0.5% reference tolerance (B grade) | Reduces calibration overhead in precision feedback paths vs. standard 1% TL431 equivalents |
| 0.2 Ω dynamic output impedance | Minimizes output voltage variation during fast load steps in SMPS feedback loops |
| Green, halogen-free packaging | Complies with RoHS 3 (2015/863/EU) and automotive environmental standards |
| Stable with ≥4.7 nF capacitive load | Enables direct integration with common optocoupler input capacitance without external compensation |
Applications
| Optocoupler Linearization | Overvoltage Protection |
|---|---|
|
Use Scenario: Isolated feedback in automotive DC-DC converters using PC817 or SFH615A optocouplers. IC Role / Device Role / Timing Role: Adjustable shunt reference setting precise LED current to linearize optocoupler CTR vs. temperature. Use Value: Maintains ±1% output regulation across -40°C to +125°C by compensating for optocoupler nonlinearity and LED forward voltage drift. |
Use Scenario: Monitoring 12 V battery rail for overvoltage events (>15.5 V) in engine control units. IC Role / Device Role / Timing Role: Precision voltage threshold detector triggering shutdown via microcontroller GPIO or discrete transistor switch. Use Value: Achieves 50 mV trip accuracy (±0.5% × 10 V) with no external trimming, reducing BOM count versus discrete zener+op-amp solutions. |
| Linear Regulator Reference | Variable Reference Generator |
|
Use Scenario: High-stability reference for LDOs powering ADAS sensor signal chains (e.g., radar MMIC bias). IC Role / Device Role / Timing Role: Low-noise, low-drift reference source for error amplifier in three-terminal fixed-output regulators. Use Value: Delivers <34 mV reference deviation over full automotive temperature range, improving LDO output accuracy by 2× vs. standard TL431. |
Use Scenario: Programmable voltage setpoint in battery management system cell balancers (2.5–4.3 V range). IC Role / Device Role / Timing Role: Adjustable reference node scaled via DAC-controlled resistor network for adaptive voltage thresholds. Use Value: Enables 10-bit effective resolution (0.5% × 2.5 V = 12.5 mV step) with only two external resistors and no trimming required. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar adjustable shunt regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431BIDBVR | 0.5% tolerance, but rated only to +105°C; no AEC-Q100 qualification; 2.495 V nominal VREF | Limited to industrial/commercial automotive peripherals (e.g., infotainment), not powertrain or safety-critical modules | Select when cost is primary constraint and ambient temperature stays below +105°C |
| ZTL432BQFTA | Identical electrical specs but SOT23 pinout differs: Ref and Anode swapped (Pin 1=Ref, Pin 3=Anode) | Requires PCB layout revision; incompatible with existing ZTL431 footprints without trace modification | Select only for new designs where pinout flexibility is prioritized over drop-in replacement |
Compared with TL431BIDBVR, ZTL431BQFTA delivers extended temperature range and automotive qualification at modest cost premium; compared with ZTL432BQFTA, it retains legacy pin compatibility for seamless migration from TL431 layouts.
Availability
ZTL431BQFTA is available at Aetrix Electronics and suitable for automotive power supply feedback, overvoltage protection circuits, and precision linear regulator references requiring stable component supply across extended temperature ranges.
Supply support for ZTL431BQFTA 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
Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability components for automotive, industrial, and computing markets.
ZTL431BQFTA belongs to Diodes' automotive-qualified precision reference family, designed specifically for AEC-Q100-compliant feedback and protection circuits in harsh-environment vehicle systems.
FAQ
What is the minimum cathode current required for regulation in ZTL431BQFTA?
The ZTL431BQFTA requires a minimum cathode current of 0.4–0.6 mA to maintain regulation, as specified in the datasheet's Electrical Characteristics table. This ensures stable reference operation even under light-load conditions typical in optocoupler biasing or high-resistance divider networks.
Can ZTL431BQFTA replace TL431 in existing designs?
Yes, ZTL431BQFTA is functionally compatible with TL431 in SOT23 footprint, offering identical pinout and improved specifications: 0.5% reference tolerance, -40°C to +125°C operation, and AEC-Q100 qualification. No circuit changes are needed beyond verifying cathode voltage remains ≤20 V.
What capacitor value ensures stability with ZTL431BQFTA?
A minimum 4.7 nF capacitor between anode and cathode is recommended to ensure stability across all operating conditions, per the datasheet's Stability Boundary guidance. This value accommodates typical optocoupler input capacitance and eliminates need for additional compensation components.
Is ZTL431BQFTA lead-free and RoHS compliant?
Yes, ZTL431BQFTA is fully RoHS 3 compliant (2015/863/EU), lead-free, halogen-free, and antimony-free per Diodes Incorporated's "Green" definition (<900 ppm Br/Cl, <1000 ppm Sb), with matte tin-plated terminations meeting MIL-STD-202 solderability requirements.
ZTL431BQFTA Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- 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):
- 2.5V
- Voltage - Output (Max):
- 20 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:
- -40°C ~ 125°C (TA)
- Grade:
- Automotive
- Qualification:
- AEC-Q100
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
ZTL431BQFTA FAQ
1.How can I place an order for ZTL431BQFTA through Aetrix?
Please submit a Request for Quotation (RFQ) for ZTL431BQFTA 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 ZTL431BQFTA reliable?
The price and inventory of ZTL431BQFTA are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ZTL431BQFTA is usually 5 days.
3.What payment methods are accepted for ZTL431BQFTA?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ZTL431BQFTA transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for ZTL431BQFTA?
ZTL431BQFTA orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your ZTL431BQFTA 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 ZTL431BQFTA?
For technical support, including ZTL431BQFTA datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ZTL431BQFTA requirements.
6.How does Aetrix verify that ZTL431BQFTA is sourced from the original manufacturer or authorized distributors?
All ZTL431BQFTA 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 ZTL431BQFTA meets industry standards.
7.What is the process for return or replacement of ZTL431BQFTA?
All ZTL431BQFTA units undergo pre-shipment inspection (PSI). If there is an issue with ZTL431BQFTA, 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 ZTL431BQFTA part is unused and in its original packaging.
Return procedure for ZTL431BQFTA:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
ZTL431BQFTA Tags
-
TL431AIDBZR
Texas Instruments
-
TL431BQDBZR
Texas Instruments
-
AN431AN-ATRG1
Diodes Incorporated
-
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
Tech Hub
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
LDO regulator guide covering low dropout voltage, power dissipation, thermal design, PSRR, output noise, capacitor stability, adjustable LDO circuits, LDO vs buck converter and datasheet selection chec…
Conditional Access Module guide covering CAM meaning, CI/CI+ interface, smart card authorization, DVB security workflow, TV and set-top box compatibility, internal electronics, ESD protection, connecto…
Guide to electronic component obsolescence covering EOL risk, PCN/PDN notices, last-time buy planning, replacement options, form-fit-function validation, counterfeit risk and BOM lifecycle management.
18650 battery guide covering lithium-ion cell basics, 3.6V/3.7V voltage, 4.2V charging, mAh and Wh capacity, protected cells, chargers, BMS, series-parallel packs, holders, welding and sourcing checks.…
Hall effect sensor guide covering working principle, linear and digital sensors, Arduino circuits, current sensing, speed detection, automotive applications, A3144 examples, signal filtering and datash…
Product Change Notification guide for electronic components, covering PCN meaning, PCN vs PDN/EOL, common change types, risk levels, form-fit-function review, engineering validation, BOM control, LTB/L…
A practical guide to blend door actuators, covering HVAC function, symptoms, location, AC and heater issues, reset and calibration, replacement cost, electrical diagnosis, compatibility checks, and rep…
