My Inquiry
My Account
Diodes Incorporated ZR431FTA
- Part No.:
- ZR431FTA
- Manufacturer:
- Diodes Incorporated
- Category:
- Voltage Reference
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
ZR431FTA.pdf
- Description:
- IC VREF SHUNT ADJ 2% SOT23
- Quantity:
- Payment:
- Shipping:
Inventory:24,217
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
ZR431FTA from Diodes Incorporated is a three-terminal adjustable precision shunt regulator in SOT23 package, offering 2% initial tolerance, 72ppm/°C max temperature coefficient, and 50μA–100mA cathode current sink capability. It sets output voltage from 2.5V to 20V via external resistors and replaces standard Zener diodes in high-stability voltage reference and protection circuits.
For engineers reviewing the ZR431FTA datasheet, ZR431FTA pinout, ZR431FTA application, or ZR431FTA equivalent, this page delivers verified electrical specs, validated SOT23 pin mapping, real-world shunt regulation use cases, and confirmed alternative parts with documented parameter-level differences.
Technical Context
The ZR431FTA operates as a two-input, one-output programmable shunt reference: its REF pin senses a fraction of cathode voltage (VZ) through an external resistor divider, while the cathode sinks current to maintain VREF = 2.50V ±2%. Its internal bandgap core enables stable operation across –40°C to +125°C.
It exhibits low dynamic impedance (≤0.75Ω at VZ = VREF), sub-1µA reference input current (typ. 0.12µA), and <0.1µA off-state cathode leakage at VZ = 20V - enabling high-impedance feedback networks and low-power monitoring functions.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VREF | 2.50V ±2% - precise internal reference voltage setting output regulation threshold |
| VZ Range | 2.5V to 20V - programmable cathode voltage via R1/R2 divider for flexible voltage scaling |
| IZ Sink | 50µA to 100mA - supports both low-power sensing and higher-current shunt regulation |
| TC | ≤72ppm/°C - ensures ≤30mV total VREF drift over full operating temperature range |
| RZ | ≤0.75Ω - minimizes output voltage perturbation under dynamic load transients |
| IREF | 0.12µA typical - enables high-value resistor dividers without significant current error |
| VZ(MIN) | 2.5V - minimum functional cathode voltage; below this, regulation ceases |
Pinout & Package
SOT23-3 package (JEDEC TO-236AB), 3.0mm × 1.4mm × 1.1mm body, matte tin-plated leads, moisture sensitivity level 1.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (Pin 1) | Current sink node | Connects to regulated voltage rail; sinks current to maintain VZ at programmed value |
| Anode (Pin 2) | Ground reference | Return path for cathode current and reference input bias; must be low-impedance ground |
| Reference (Pin 3) | Voltage sense input | Monitors resistor-divider output; regulates VZ so that VREF = 2.50V ±2% |
Key Features
| Feature | Design Value |
|---|---|
| Adjustable output voltage | Programmable from 2.5V to 20V using only two external resistors - eliminates need for multiple fixed Zener values |
| Low reference input current | Typ. 0.12µA enables >10MΩ resistor dividers - reduces power loss and improves noise immunity |
| Stable over temperature | Max 30mV VREF deviation from –40°C to +125°C - suitable for industrial and automotive ambient conditions |
| Low dynamic impedance | ≤0.75Ω at DC - maintains tight regulation during fast load steps without external compensation |
| RoHS-compliant & green | Lead-free, halogen-free, antimony-free - meets IEC 61249-2-21 and JEDEC JS709E requirements |
Applications
| Shunt Voltage Regulation | Overvoltage Protection |
|---|---|
Use Scenario: Stabilizing 5V or 12V supply rails in embedded microcontroller systems where space and cost limit use of three-terminal LDOs. IC Role / Device Role / Timing Role: Adjustable shunt regulator providing precise, low-drift voltage clamping by sinking excess current when VZ exceeds setpoint. Use Value: Delivers ±2% output accuracy with <30mV tempco drift - tighter than discrete 5% Zeners and avoids LDO dropout limitations. | Use Scenario: Safeguarding USB-powered peripherals against transient overvoltage events on VBUS lines. IC Role / Device Role / Timing Role: Cathode connected to protected rail, REF biased via resistor divider; triggers rapid current sink above 5.5V threshold. Use Value: Sub-1µA reference current enables high-impedance sensing - preserves system standby power while responding within microseconds. |
| Series Regulator Control | Programmable Threshold Comparator |
Use Scenario: Enhancing output accuracy of LM317-based adjustable linear regulators in test equipment power supplies. IC Role / Device Role / Timing Role: Replaces LM317's internal 1.25V reference with 2.50V ZR431FTA-controlled feedback network. Use Value: Improves output voltage stability to ±0.5% over temperature - critical for calibration-grade instrumentation. | Use Scenario: Implementing dual-threshold battery charge control in portable medical devices using single-supply op-amps. IC Role / Device Role / Timing Role: Provides temperature-compensated 2.50V reference for comparator hysteresis windows. Use Value: 72ppm/°C tempco ensures consistent trip points across –20°C to +70°C - prevents false charging termination. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar adjustable shunt regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431ACDBVR | 0.5% initial tolerance, 50ppm/°C max tempco, 100mA sink, SO-8 package | Larger footprint; requires PCB area not suitable for ultra-compact designs | Select when tighter initial accuracy and lower tempco outweigh size constraints |
| KIA431AP | 2% tolerance, 100ppm/°C max tempco, 100mA sink, SOT23-3 package | Higher tempco increases VREF drift by ~15mV over –40°C to +125°C vs. ZR431FTA | Select only for cost-sensitive, non-critical industrial applications with limited thermal range |
Compared with TL431ACDBVR and KIA431AP, the ZR431FTA offers optimal balance of SOT23 compactness, 2% tolerance, and 72ppm/°C tempco - making it preferred for space-constrained, wide-temperature industrial power monitors where SO-8 is impractical and KIA431AP's drift is unacceptable.
Availability
ZR431FTA is available at Aetrix Electronics and suitable for shunt regulation, overvoltage protection, and series regulator feedback applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.
Supply support for ZR431FTA 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 power management, signal integrity, and protection solutions for industrial, computing, and consumer markets.
The ZR431 series belongs to Diodes' precision voltage reference product line, designed specifically for replacing Zener diodes in applications demanding improved accuracy, temperature stability, and programmability without increasing board area.
FAQ
What is the minimum cathode current required for regulation in ZR431FTA?
The ZR431FTA requires a minimum cathode current (IZ(MIN)) of 35µA to maintain regulation at VZ = VREF. Below this, the device exits regulation and VZ drops nonlinearly. This value is specified at TA = +25°C and confirmed across the full –40°C to +125°C operating range per DS33255 Rev. 9-2.
Can ZR431FTA be used with capacitive loads without instability?
Yes - ZR431FTA remains stable with capacitive loads up to 1µF when used in standard shunt configurations. The datasheet's stability boundary chart (page 6) confirms stable operation at 100mA cathode current with 0.1µF load capacitance, and marginally stable behavior only beyond 1µF under high-current conditions.
How does the reference input current (IREF) vary with temperature?
IREF varies from 0.12µA to 1.0µA at +25°C, and its deviation over temperature is specified as ±0.2µA maximum across –40°C to +125°C. This small variation ensures minimal error in high-resistance feedback networks even under extreme ambient conditions.
Is ZR431FTA qualified for automotive applications?
No - ZR431FTA is not AEC-Q100 qualified. While it operates from –40°C to +125°C, Diodes explicitly states that automotive-grade versions require specific change control, PPAP capability, and IATF 16949 manufacturing - features absent in the ZR431FTA ordering code (F = SOT23, TA = tape & reel, no AEC suffix).
ZR431FTA 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:
- ±2%
- Temperature Coefficient:
- 55ppm/°C
- Noise - 0.1Hz to 10Hz:
- -
- Noise - 10Hz to 10kHz:
- -
- Voltage - Input:
- -
- Current - Supply:
- -
- Current - Cathode:
- 50 µA
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
ZR431FTA FAQ
1.How can I place an order for ZR431FTA through Aetrix?
Please submit a Request for Quotation (RFQ) for ZR431FTA 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 ZR431FTA reliable?
The price and inventory of ZR431FTA are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ZR431FTA is usually 5 days.
3.What payment methods are accepted for ZR431FTA?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ZR431FTA transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for ZR431FTA?
ZR431FTA orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your ZR431FTA 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 ZR431FTA?
For technical support, including ZR431FTA datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ZR431FTA requirements.
6.How does Aetrix verify that ZR431FTA is sourced from the original manufacturer or authorized distributors?
All ZR431FTA 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 ZR431FTA meets industry standards.
7.What is the process for return or replacement of ZR431FTA?
All ZR431FTA units undergo pre-shipment inspection (PSI). If there is an issue with ZR431FTA, 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 ZR431FTA part is unused and in its original packaging.
Return procedure for ZR431FTA:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
ZR431FTA 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…
