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STMicroelectronics TS3431AIZ
- Part No.:
- TS3431AIZ
- Manufacturer:
- STMicroelectronics
- Category:
- Voltage Reference
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
TS3431AIZ.pdf
- Description:
- IC VREF SHUNT ADJ 1% SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:2,933
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Product details
Overview
TS3431AIZ from STMicroelectronics is a precision programmable shunt voltage reference in TO-92 package, delivering 1.24V to 24V adjustable output with ±1% initial accuracy at 25°C, 100 ppm/°C temperature coefficient, and -40°C to +125°C industrial operating range. It sinks 0.5–100 mA cathode current and serves as a stable reference in feedback loops of isolated DC-DC converters and battery charger regulation circuits.
For engineers reviewing the TS3431AIZ datasheet, TS3431AIZ pinout, TS3431AIZ application, or TS3431AIZ equivalent, key selection criteria include guaranteed ±1% tolerance over full temperature range, low 100 nV/√Hz wideband noise, sub-1 µA reference input current, and compatibility with TL431-based designs requiring extended thermal stability and tighter initial accuracy.
Technical Context
The TS3431AIZ operates as a two-terminal shunt regulator, where cathode-anode voltage is set by an external resistor divider connected to its reference terminal. Its internal bandgap core ensures monotonic output voltage vs. temperature across -40°C to +125°C, with only 21 mV total variation over that range.
It features low dynamic impedance (0.2–0.4 Ω), fast pulse response (<8 µs settling at 10 mA), and minimal off-state cathode leakage (≤500 nA at 25°C). The device requires no external compensation and maintains stable operation under varying load and line conditions without oscillation.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage Range | 1.24 V to 24 V - Programmable via external resistive divider; enables flexible feedback design for diverse supply rails. |
| Initial Accuracy | ±1% at 25°C - Guarantees tight regulation without post-manufacturing trimming in production systems. |
| Tempco | 100 ppm/°C - Ensures predictable, linear drift enabling accurate error budgeting in wide-temperature applications. |
| Cathode Current Range | 0.5 mA to 100 mA - Supports high-side sensing and robust sink capability for optocoupler-driven feedback paths. |
| Reference Input Current | 0.9–1.5 µA - Minimizes divider power loss and improves efficiency in battery-powered systems. |
| Dynamic Impedance | 0.2–0.4 Ω - Provides low AC impedance for stable loop gain in SMPS feedback networks. |
| Wideband Noise | 100 nV/√Hz (1–100 kHz) - Reduces voltage reference jitter critical for high-resolution ADC references and precision DACs. |
Pinout & Package
TS3431AIZ uses the TO-92 plastic through-hole package (3-pin, straight lead configuration), optimized for manual assembly and prototyping. Pin 1 = Anode, Pin 2 = Cathode, Pin 3 = Reference (adjust) terminal.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode (Pin 1) | Current return path | Connected to system ground or low-side return; defines reference node for divider network. |
| Cathode (Pin 2) | Regulated output node | Sinks current to maintain programmed voltage; drives optocoupler LED or error amplifier input. |
| Reference (Pin 3) | Feedback sense input | High-impedance input monitoring divided output; sets regulation point via R1/R2 ratio. |
Key Features
| Feature | Design Value |
|---|---|
| Guaranteed temp stability | ±21 mV max ΔVREF over -40°C to +125°C - Eliminates need for external temperature compensation in automotive and industrial controls. |
| Low IREF | ≤1.5 µA at 25°C - Enables use with high-value divider resistors (>1 MΩ), reducing quiescent power in always-on systems. |
| TL431-compatible footprint | TO-92 mechanical and functional match - Allows drop-in replacement in legacy designs without PCB rework. |
| Robust ESD rating | 2 kV HBM - Withstands handling and board-level transients without parameter shift or failure. |
Applications
| Switch Mode Power Supply | Battery Charger |
|---|---|
Use Scenario: Primary-side feedback in isolated flyback converters using optocoupler-coupled error signal. IC Role / Device Role / Timing Role: Shunt voltage reference providing precise regulation setpoint to optocoupler LED driver. Use Value: ±1% accuracy and 100 ppm/°C tempco ensure consistent output voltage across line/load/temperature, meeting USB PD and telecom standards. | Use Scenario: Constant-voltage stage control in multi-cell Li-ion chargers with microcontroller supervision. IC Role / Device Role / Timing Role: Precision reference for ADC measurement and comparator threshold generation. Use Value: Sub-µA IREF minimizes bias error in high-resistance voltage dividers used for cell voltage monitoring. |
| Instrumentation | Computers |
Use Scenario: Calibration reference in portable multimeters and data loggers requiring traceable accuracy. IC Role / Device Role / Timing Role: Stable 2.5V or 5V reference source for SAR ADCs and analog front-ends. Use Value: 100 nV/√Hz noise floor preserves effective resolution in 16-bit+ measurement systems. | Use Scenario: VRM remote sensing and motherboard voltage margining in server and desktop platforms. IC Role / Device Role / Timing Role: Adjustable reference for programmable voltage supervisor ICs and PMIC feedback. Use Value: 1.24–24 V adjustability supports multiple rail configurations (1.8V, 3.3V, 5V, 12V) on single BOM. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt voltage reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431ACZ | ±1% initial accuracy, but higher 120 ppm/°C tempco and 500 nV/√Hz noise | Limited to ≤85°C ambient; less suitable for under-hood or industrial enclosures | Prefer when cost sensitivity outweighs thermal performance requirements |
| MAX6008AEUR+T | Fixed 2.048V output, ±0.1% accuracy, 30 ppm/°C tempco, SOT23-3 package | No programmability; requires redesign for non-2.048V applications | Select only for fixed-voltage, ultra-low-drift needs where space constraints prohibit TO-92 |
Compared with TL431ACZ and MAX6008AEUR+T, TS3431AIZ uniquely balances programmability, ±1% accuracy, 100 ppm/°C stability, and TO-92 manufacturability-making it optimal for cost-sensitive, thermally demanding, adjustable-reference designs where pin compatibility and proven field reliability are essential.
Availability
TS3431AIZ is available at Aetrix Electronics and suitable for switch mode power supplies, battery chargers, instrumentation, and computer power management systems requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for TS3431AIZ 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
STMicroelectronics is a global semiconductor leader headquartered in Geneva, designing and manufacturing analog, MCU, power, and sensor solutions for industrial, automotive, and consumer markets.
The TS3431 series belongs to ST's precision analog portfolio, engineered specifically for high-stability voltage reference applications in harsh thermal environments where TL431-grade performance is insufficient.
FAQ
What is the minimum cathode current required for regulation at -40°C?
The TS3431AIZ requires a minimum cathode current of 0.5 mA across the full -40°C to +125°C range to maintain regulation. This value is guaranteed per Table 3 and Figure 5 in the datasheet, ensuring reliable startup and stability even at extreme cold temperatures.
Can TS3431AIZ replace TL431 in existing TO-92 designs without modification?
Yes-TS3431AIZ shares identical TO-92 pinout (Anode–Cathode–Ref), same electrical interface, and TL431-compatible transfer function. No PCB or schematic changes are needed; only verify that the ±1% accuracy and lower tempco meet system specifications.
How does the 100 ppm/°C temperature coefficient impact output voltage at +125°C?
With a nominal 2.5V setting, the 100 ppm/°C tempco yields a maximum drift of ±0.025 V over 100°C (25°C to 125°C), contributing ≤1% additional error beyond initial ±1% tolerance-well within typical SMPS output spec limits.
Is the TS3431AIZ suitable for use with optocouplers in isolated feedback circuits?
Yes-its 0.5–100 mA cathode sink capability directly drives standard PC817 or SFH615A optocoupler LEDs. The low dynamic impedance (0.2–0.4 Ω) ensures stable current delivery and fast transient response during load steps.
TS3431AIZ Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Series:
- -
- Packaging:
- Bulk
- Product Status:
- Obsolete
- Reference Type:
- Shunt
- Output Type:
- Adjustable
- Voltage - Output (Min/Fixed):
- 1.24V
- Voltage - Output (Max):
- 24 V
- Current - Output:
- 100 mA
- Tolerance:
- ±1%
- Temperature Coefficient:
- 100ppm/°C
- Noise - 0.1Hz to 10Hz:
- -
- Noise - 10Hz to 10kHz:
- -
- Voltage - Input:
- -
- Current - Supply:
- -
- Current - Cathode:
- 500 µA
- Operating Temperature:
- -40°C ~ 125°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
TS3431AIZ FAQ
1.How can I place an order for TS3431AIZ through Aetrix?
Please submit a Request for Quotation (RFQ) for TS3431AIZ 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 TS3431AIZ reliable?
The price and inventory of TS3431AIZ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TS3431AIZ is usually 5 days.
3.What payment methods are accepted for TS3431AIZ?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TS3431AIZ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TS3431AIZ?
TS3431AIZ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TS3431AIZ 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 TS3431AIZ?
For technical support, including TS3431AIZ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TS3431AIZ requirements.
6.How does Aetrix verify that TS3431AIZ is sourced from the original manufacturer or authorized distributors?
All TS3431AIZ 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 TS3431AIZ meets industry standards.
7.What is the process for return or replacement of TS3431AIZ?
All TS3431AIZ units undergo pre-shipment inspection (PSI). If there is an issue with TS3431AIZ, 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 TS3431AIZ part is unused and in its original packaging.
Return procedure for TS3431AIZ:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TS3431AIZ Tags
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TL431AIDBZR
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TL431BQDBZR
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AN431AN-ATRG1
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LM4040CYM3-2.5-TR
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LM4040CYM3-4.1-TR
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LM4040EIM3-2.5/NOPB
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AZ431LBNTR-G1
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LM4040D20IDBZR
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LM4041DIM3-ADJ/NOPB
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LM4040DIM3X-2.5/NOPB
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LM4040DIM3-2.5/NOPB
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AZ431LANTR-G1
Diodes Incorporated
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