My Inquiry
My Account
Texas Instruments ATL431BIDBZR
- Part No.:
- ATL431BIDBZR
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
ATL431BIDBZR.pdf
- Description:
- IC VREF SHUNT ADJ 0.5% SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:34,182
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
ATL431BIDBZR from Texas Instruments is a 2.5V adjustable precision shunt regulator in SOT-23 package, delivering 0.5% initial reference voltage tolerance at 25°C, 35µA minimum cathode current, and 0.3Ω maximum dynamic impedance for secondary-side regulation in isolated flyback SMPSs.
For engineers reviewing the ATL431BIDBZR datasheet, ATL431BIDBZR pinout, ATL431BIDBZR application, or ATL431BIDBZR equivalent, this device serves as a low-IQ Zener replacement with extended cathode current range (35µA–100mA), stable operation without output capacitance, and precise voltage referencing across –40°C to +85°C.
Technical Context
The ATL431BIDBZR operates as a three-terminal adjustable shunt regulator with an internal 2.5V bandgap reference and high-gain error amplifier driving a Darlington output stage. Its open-loop gain enables comparator-mode operation, while closed-loop feedback via external resistors sets regulated cathode voltage from 2.5V to 36V.
Internally compensated design ensures stability with no capacitive load, and its 5mV typical VREF drift over –40°C to +85°C supports tight regulation in industrial power supplies. The device requires ≥35µA cathode current to maintain linear operation and reference accuracy.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VREF tolerance | ±0.5% at 25°C - ensures initial output accuracy for precision feedback loops |
| Min cathode current | 35µA max - enables ultra-low-power regulation and no-load efficiency in SMPS |
| Dynamic impedance | 0.3Ω max - provides low-output-impedance voltage reference under load transients |
| VREF temp drift | 5mV over –40°C to +85°C - maintains regulation stability across industrial temperature range |
| Cathode voltage range | 2.5V to 36V - supports wide-range programmable output using two external resistors |
| IREF | 150nA max - minimizes resistor-divider loading error in high-impedance feedback networks |
| ESD rating | ±2000V HBM - ensures robustness during board handling and assembly |
Pinout & Package
ATL431BIDBZR is housed in a 3-pin SOT-23 (DBZ) package measuring 2.90mm × 1.60mm, with standard lead pitch and thermal performance (RθJA = 331.8°C/W).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| CATHODE (Pin 1) | Shunt current input / regulated output node | Accepts 35µA–100mA sink current; voltage at this pin is set by external resistor divider |
| REF (Pin 2) | Reference input / feedback sense node | Compares external voltage to internal 2.5V reference; draws ≤150nA, enabling high-R divider designs |
| ANODE (Pin 3) | Common return / ground reference | Acts as circuit ground reference point; all voltages referenced to this pin |
Key Features
| Feature | Design Value |
|---|---|
| Adjustable output range | 2.5V to 36V via two external resistors - eliminates need for multiple fixed-voltage references |
| No-capacitor stability | Internally compensated - removes output capacitor requirement, reducing BOM count and layout area |
| Ultra-low IQ | 35µA min cathode current - cuts standby power in isolated converters by >20× vs TL431 |
| Low output impedance | 0.3Ω max - improves transient response and reduces output voltage deviation under load steps |
| High-accuracy grade | 0.5% VREF tolerance (B grade) - enables tighter output regulation without post-production trimming |
Applications
| Secondary-Side Regulation | Zener Diode Replacement |
|---|---|
Use Scenario: Voltage feedback in isolated flyback converters where primary-side sensing is impractical. IC Role / Device Role / Timing Role: Shunt regulator and error amplifier providing isolated output voltage sensing and regulation. Use Value: Enables accurate ±1% output regulation with <35µA quiescent current, improving no-load efficiency in AC/DC adapters and telecom PSUs. |
Use Scenario: Precision voltage clamping or reference generation in linear regulators and protection circuits. IC Role / Device Role / Timing Role: Adjustable 2.5V–36V shunt reference replacing discrete Zener diodes with poor tempco and tolerance. Use Value: Delivers 0.5% initial accuracy and 5mV temp drift vs typical Zener's 5–10% tolerance and >50mV drift, reducing calibration overhead. |
| Comparator with Reference | Adjustable Current Reference |
Use Scenario: Overvoltage/undervoltage monitoring in battery management and power sequencing circuits. IC Role / Device Role / Timing Role: Open-loop comparator with integrated 2.5V reference for threshold detection. Use Value: Eliminates external reference IC; 150nA IREF allows high-impedance sensing with minimal loading on source signals. |
Use Scenario: Programmable constant-current source for LED drivers or sensor excitation. IC Role / Device Role / Timing Role: Precision current sink configured via cathode-to-anode voltage and series resistor. Use Value: Achieves <1% current accuracy over temperature using same 0.5% VREF and low-impedance output, replacing op-amp + reference combos. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431BIDBZR | Higher 100µA min cathode current; 2% VREF tolerance; wider temp range (–40°C to +125°C for Q grade) | Less suitable for ultra-low-power no-load operation; higher IQ increases standby loss in energy-sensitive designs | Select TL431BIDBZR only when legacy compatibility or extended temperature range is mandatory and 0.5% accuracy is not required. |
| ATL431LIYPR | Same 0.5% tolerance and 35µA IK(min), but rated for –40°C to +125°C (Q grade); identical pinout and electrical specs | Direct drop-in for automotive or extended-temp industrial use where ATL431BIDBZR's 85°C limit is insufficient | Choose ATL431LIYPR when operating ambient exceeds +85°C; otherwise, ATL431BIDBZR offers optimal cost/performance for commercial/industrial use. |
Compared with TL431BIDBZR, ATL431BIDBZR delivers 20× lower minimum cathode current and tighter 0.5% reference accuracy-critical for high-efficiency flyback designs-while ATL431LIYPR extends temperature capability without sacrificing performance or pin compatibility.
Availability
ATL431BIDBZR is available at Aetrix Electronics and suitable for industrial power supplies, isolated DC-DC converters, and precision voltage monitoring systems requiring stable component supply and long-term manufacturability.
Supply support for ATL431BIDBZR 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 designing analog and embedded processing solutions for industrial, automotive, and communications markets.
The ATL43x product line was developed to replace TL431 in high-efficiency, low-quiescent-power applications-specifically targeting secondary-side regulation in isolated switch-mode power supplies with stringent no-load and thermal requirements.
FAQ
What is the reference voltage accuracy of ATL431BIDBZR at 25°C?
The ATL431BIDBZR has a reference voltage tolerance of ±0.5% at 25°C, meaning its VREF falls between 2.487V and 2.512V under nominal conditions. This B-grade accuracy is confirmed in Section 5.6 of the datasheet and enables high-precision feedback in regulated power supplies without external trimming. ATL431BIDBZR maintains this specification across its full cathode current range (35µA–100mA) and is validated per TI's production test flow.
Can ATL431BIDBZR operate without an output capacitor?
Yes, ATL431BIDBZR is internally compensated and stable with no output capacitance between cathode and anode-a key differentiator from older shunt regulators. This eliminates capacitor-related BOM cost, footprint, and aging concerns. Stability boundaries are defined in Figures 5-14 through 5-21 of the datasheet, confirming robust operation across 0.1pF–2000pF load capacitance and 35µA–100mA cathode current. ATL431BIDBZR achieves this via optimized internal compensation network, not external components.
What is the minimum cathode current required for regulation in ATL431BIDBZR?
The ATL431BIDBZR requires a minimum cathode current of 35µA (maximum specified) to maintain regulation and reference accuracy. This value is guaranteed across temperature (–40°C to +85°C) and is significantly lower than TL431's 100µA minimum-enabling >20× improvement in no-load efficiency for flyback converters. Below 35µA, gain drops and VREF accuracy degrades; ATL431BIDBZR's IK(min) is verified per Figure 5-5 and Section 5.6 test conditions.
How does ATL431BIDBZR differ from ATL431LIYPR?
ATL431BIDBZR and ATL431LIYPR share identical electrical specifications-including 0.5% VREF tolerance, 35µA IK(min), and 0.3Ω dynamic impedance-but differ in temperature rating: ATL431BIDBZR is rated for –40°C to +85°C (I grade), while ATL431LIYPR is rated for –40°C to +125°C (Q grade). Both use the same SOT-23 (DBZ) package and pinout, making ATL431LIYPR a direct thermal upgrade. ATL431BIDBZR remains optimal for cost-sensitive commercial/industrial applications within its temperature envelope.
Is ATL431BIDBZR pin-compatible with TL431 devices?
Yes, ATL431BIDBZR uses the same 3-pin SOT-23 (DBZ) package and pinout as TL431BIDBZR: Pin 1 = CATHODE, Pin 2 = REF, Pin 3 = ANODE. This allows direct PCB-level replacement in existing TL431 designs without layout changes. However, due to its lower IK(min) and improved stability, system-level validation is recommended-especially for no-load efficiency and transient response. ATL431BIDBZR's enhanced specs do not compromise backward compatibility.
ATL431BIDBZR 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:
- Active
- Reference Type:
- Shunt
- Output Type:
- Adjustable
- Voltage - Output (Min/Fixed):
- 2.5V
- Voltage - Output (Max):
- 36 V
- Current - Output:
- 100 mA
- Tolerance:
- ±0.5%
- Temperature Coefficient:
- 48ppm/°C
- Noise - 0.1Hz to 10Hz:
- -
- Noise - 10Hz to 10kHz:
- -
- Voltage - Input:
- -
- Current - Supply:
- -
- Current - Cathode:
- 35 µA
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
ATL431BIDBZR FAQ
1.How can I place an order for ATL431BIDBZR through Aetrix?
Please submit a Request for Quotation (RFQ) for ATL431BIDBZR 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 ATL431BIDBZR reliable?
The price and inventory of ATL431BIDBZR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ATL431BIDBZR is usually 5 days.
3.What payment methods are accepted for ATL431BIDBZR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ATL431BIDBZR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for ATL431BIDBZR?
ATL431BIDBZR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your ATL431BIDBZR 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 ATL431BIDBZR?
For technical support, including ATL431BIDBZR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ATL431BIDBZR requirements.
6.How does Aetrix verify that ATL431BIDBZR is sourced from the original manufacturer or authorized distributors?
All ATL431BIDBZR 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 ATL431BIDBZR meets industry standards.
7.What is the process for return or replacement of ATL431BIDBZR?
All ATL431BIDBZR units undergo pre-shipment inspection (PSI). If there is an issue with ATL431BIDBZR, 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 ATL431BIDBZR part is unused and in its original packaging.
Return procedure for ATL431BIDBZR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
ATL431BIDBZR 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
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
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…
