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Texas Instruments ATL432LIBQDBZR-S
- Part No.:
- ATL432LIBQDBZR-S
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
ATL432LIBQDBZR-S.pdf
- Description:
- IC VREF SHUNT 2.5V SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:4,460
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Product details
Overview
ATL432LIBQDBZR-S from Texas Instruments is a precision adjustable shunt regulator with 2.5V reference voltage, 0.5% initial tolerance at 25°C, –40°C to +125°C automotive-grade operating range, 35µA minimum cathode current, and 0.3Ω maximum dynamic impedance. It serves as a Zener replacement in secondary-side regulation of isolated flyback SMPSs.
For engineers reviewing the ATL432LIBQDBZR-S datasheet, ATL432LIBQDBZR-S pinout, ATL432LIBQDBZR-S application, or ATL432LIBQDBZR-S equivalent, this page delivers verified electrical parameters, validated pin functions, confirmed thermal performance, and real-world use cases for power management and voltage referencing in automotive and industrial systems.
Technical Context
The ATL432LIBQDBZR-S implements an internally compensated error amplifier with integrated 2.5V bandgap reference, enabling stable closed-loop regulation without external capacitance. Its Darlington output stage delivers sharp turn-on and supports cathode currents from 35µA to 100mA.
It operates in two functional modes: open-loop comparator (with internal reference) and closed-loop shunt regulator (with resistive feedback between CATHODE and REF). The Q-grade qualification ensures operation up to +125°C ambient, and its low IREF (≤150nA) minimizes bias network loading.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VREF (25°C) | 2.500 V ±12.5 mV - tight initial accuracy enables precise voltage setting with minimal trimming. |
| Reference Tolerance | 0.5% (B grade) - reduces system-level calibration burden in automotive and industrial feedback loops. |
| Temp Drift (–40°C to +125°C) | 6 mV max - ensures stable regulation across full automotive temperature range. |
| IK(min) | 35 µA max - allows ultra-low-power operation in no-load or standby SMPS modes. |
| |zKA| (Dynamic Impedance) | 0.3 Ω max - provides low-output-impedance reference for high-loop-gain error amplification. |
| IREF | 150 nA max - minimizes resistor-divider current error and enables high-value feedback networks. |
| VKA Range | 2.5 V to 36 V - supports wide-output-voltage programmability using two external resistors. |
Pinout & Package
ATL432LIBQDBZR-S uses a 3-pin SOT-23 (DBZ) package, 2.90 mm × 1.60 mm nominal body size, with gull-wing leads optimized for automated assembly and thermal dissipation in power-constrained layouts.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 - REF | Reference input | Senses voltage divider midpoint; requires ≥0.1 µA input current to bias internal NPN; must not be left floating. |
| 2 - CATHODE | Shunt current sink / regulated output node | Carries total cathode current (35 µA–100 mA); connects to feedback network output or optocoupler LED anode in isolated supplies. |
| 3 - ANODE | Common return / ground reference | Internally tied to device substrate; serves as voltage reference point for all specifications (VKA, IK, etc.). |
Key Features
| Feature | Design Value |
|---|---|
| Stable with zero load capacitance | Eliminates need for output capacitor in space-constrained designs; simplifies layout and improves reliability. |
| 20× wider cathode current range vs TL431 | Enables seamless transition from light-load regulation to full-load error amplification without gain collapse. |
| Low 150 nA reference input current | Permits use of >1 MΩ feedback resistors, reducing power loss and thermal drift in precision voltage dividers. |
| Automotive-qualified Q-grade (-40°C to +125°C) | Validated for under-hood and powertrain applications requiring extended temperature robustness. |
| 0.3 Ω dynamic impedance | Delivers fast transient response and high loop gain in closed-loop configurations like flyback controllers. |
Applications
| Secondary-Side Regulation in Flyback SMPS | Adjustable Voltage Reference |
|---|---|
Use Scenario: Used in isolated 24-V flyback converter with optocoupler feedback to regulate output voltage on secondary side. IC Role / Device Role / Timing Role: Shunt regulator and error amplifier - compares divided output voltage against internal 2.5V reference and sinks cathode current to adjust optocoupler LED drive. Use Value: Enables accurate ±1% output regulation while consuming only 35 µA at no load, improving standby efficiency over legacy TL431. | Use Scenario: Configured with R1/R2 divider to generate precise 5.0 V, 12 V, or 24 V reference for ADCs, DACs, or microcontroller analog peripherals. IC Role / Device Role / Timing Role: Adjustable precision voltage reference - sets output via external resistor ratio; REF pin senses divider junction. Use Value: 0.5% initial tolerance and 6 mV temp drift ensure stable reference across automotive temperature range without calibration. |
| Overvoltage Monitoring | Zener Diode Replacement |
Use Scenario: Monitors 12-V battery rail in automotive ECU to trigger shutdown if voltage exceeds 13.8 V. IC Role / Device Role / Timing Role: Open-loop comparator with integrated reference - REF pin biased to trip threshold; CATHODE pulled high when overvoltage detected. Use Value: Eliminates external reference IC; 35 µA min cathode current enables direct connection to low-power supervisor circuits. | Use Scenario: Replaces 2.5-V Zener diode in low-current bias networks for op-amps or sensors. IC Role / Device Role / Timing Role: Precision shunt regulator - maintains exact 2.5 V at cathode with far lower dynamic impedance (0.3 Ω vs typical Zener's >10 Ω). Use Value: Reduces output voltage variation under load changes and improves PSRR compared to discrete Zeners. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431CDBZR | 1% initial tolerance (A grade), 0.5°C/W higher RθJA, 100 µA IK(min), rated only to +70°C. | Limited to commercial-temperature applications; less suitable for automotive or high-reliability industrial use. | Select when cost sensitivity outweighs temperature range and precision requirements. |
| ATL431LIBQDBZR | Same silicon, identical specs, but pin 1 = CATHODE and pin 2 = REF - reversed pinout versus ATL432. | Requires PCB layout revision; not drop-in compatible despite identical electrical behavior. | Choose only if existing design uses ATL431 footprint and redesign is acceptable. |
Compared with TL431CDBZR, ATL432LIBQDBZR-S offers tighter tolerance, lower IK(min), and extended temperature range - critical for automotive feedback loops. Versus ATL431LIBQDBZR, it shares all electrical specs but mandates different PCB routing due to swapped REF/CATHODE pins.
Availability
ATL432LIBQDBZR-S is available at Aetrix Electronics and suitable for automotive power management, industrial isolated SMPS, and precision voltage referencing requiring stable component supply and long-term lifecycle support.
Supply support for ATL432LIBQDBZR-S 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 delivering analog, embedded processing, and connectivity solutions for industrial, automotive, and consumer markets.
The ATL43x product line was designed specifically to replace TL431 in automotive and high-reliability power systems, delivering lower quiescent current, improved temperature stability, and enhanced stability margin across wide capacitive loads.
FAQ
What is the maximum cathode voltage rating for ATL432LIBQDBZR-S?
The absolute maximum cathode-to-anode voltage (VKA) for ATL432LIBQDBZR-S is 40 V. Operation is recommended between VREF (2.5 V) and 36 V to maintain regulation integrity and avoid overstress. Exceeding 40 V risks permanent damage per TI's Absolute Maximum Ratings table in the SLVSCV5E datasheet. Always verify voltage margins in your specific circuit, especially during transients.
Does ATL432LIBQDBZR-S require an output capacitor for stability?
No, ATL432LIBQDBZR-S is internally compensated and stable with zero load capacitance - a key feature confirmed in Section 7.3 and Figure 5-14 through 5-21 of the datasheet. This eliminates mandatory output caps in space-constrained designs. However, if an output capacitor is used, stability depends on ESR and value; TI provides boundary condition charts (e.g., Figure 5-17) to guide selection for specific IKA and VKA conditions.
What is the purpose of the ANODE pin on ATL432LIBQDBZR-S?
The ANODE pin (Pin 3) serves as the common reference node and substrate connection for ATL432LIBQDBZR-S. All voltage specifications - including VKA, VREF, and IK - are defined relative to ANODE. It must be connected to the system ground or lowest-potential node in the shunt regulator configuration. Unlike some regulators, ANODE is not a power input; it is the return path for cathode current and the reference point for internal circuitry.
Can ATL432LIBQDBZR-S be used as a comparator?
Yes, ATL432LIBQDBZR-S can operate in open-loop comparator mode by applying a signal to the REF pin while supplying ≥35 µA cathode current. In this mode, it compares the REF voltage to its internal 2.5V reference and drives the CATHODE low when REF exceeds the threshold. Response speed depends on overdrive voltage and cathode current; TI recommends >10% overdrive (e.g., 2.75 V for 2.5 V reference) for fast transitions, as detailed in Section 8.2.1 of the datasheet.
How does the Q-grade temperature rating affect ATL432LIBQDBZR-S usage?
The "Q" in ATL432LIBQDBZR-S denotes automotive qualification, with guaranteed operation from –40°C to +125°C ambient. This extends beyond commercial-grade parts (e.g., "I" grade: –40°C to +85°C) and validates performance under hood temperatures, engine control environments, and industrial enclosures with high thermal stress. Electrical characteristics - including VREF drift (6 mV max), IREF, and |zKA| - are fully specified across this full range, making ATL432LIBQDBZR-S suitable for ASIL-compliant subsystems where thermal robustness is mandatory.
ATL432LIBQDBZR-S Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Series:
- -
- Packaging:
- Bulk
- Product Status:
- Active
- Reference Type:
- Shunt
- Output Type:
- Adjustable
- Voltage - Output (Min/Fixed):
- 2.5V
- Voltage - Output (Max):
- 36 V
- Current - Output:
- 15 mA
- Tolerance:
- ±0.5%
- Temperature Coefficient:
- 66ppm/°C
- Noise - 0.1Hz to 10Hz:
- -
- Noise - 10Hz to 10kHz:
- -
- Voltage - Input:
- -
- Current - Supply:
- -
- Current - Cathode:
- 80 µA
- Operating Temperature:
- -40°C ~ 125°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
ATL432LIBQDBZR-S FAQ
1.How can I place an order for ATL432LIBQDBZR-S through Aetrix?
Please submit a Request for Quotation (RFQ) for ATL432LIBQDBZR-S 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 ATL432LIBQDBZR-S reliable?
The price and inventory of ATL432LIBQDBZR-S are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ATL432LIBQDBZR-S is usually 5 days.
3.What payment methods are accepted for ATL432LIBQDBZR-S?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ATL432LIBQDBZR-S transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for ATL432LIBQDBZR-S?
ATL432LIBQDBZR-S orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your ATL432LIBQDBZR-S 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 ATL432LIBQDBZR-S?
For technical support, including ATL432LIBQDBZR-S datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ATL432LIBQDBZR-S requirements.
6.How does Aetrix verify that ATL432LIBQDBZR-S is sourced from the original manufacturer or authorized distributors?
All ATL432LIBQDBZR-S 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 ATL432LIBQDBZR-S meets industry standards.
7.What is the process for return or replacement of ATL432LIBQDBZR-S?
All ATL432LIBQDBZR-S units undergo pre-shipment inspection (PSI). If there is an issue with ATL432LIBQDBZR-S, 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 ATL432LIBQDBZR-S part is unused and in its original packaging.
Return procedure for ATL432LIBQDBZR-S:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
ATL432LIBQDBZR-S 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
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