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ATL431LI

ACTIVE

Low-IQ programmable shunt regulator offered in an ultra-small DQN package

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TL431 ACTIVE Adjustable precision shunt regulator for cost optimized designs

Product details

VO (V) 2.5 Initial accuracy (max) (%) 0.5, 1 VO adj (min) (V) 2.5 VO adj (max) (V) 36 Iz for regulation (min) (µA) 80 Reference voltage (V) adjustable Rating Catalog Temp coeff (max) (ppm/°C) 66 Operating temperature range (°C) -40 to 125 Iout/Iz (max) (mA) 15
VO (V) 2.5 Initial accuracy (max) (%) 0.5, 1 VO adj (min) (V) 2.5 VO adj (max) (V) 36 Iz for regulation (min) (µA) 80 Reference voltage (V) adjustable Rating Catalog Temp coeff (max) (ppm/°C) 66 Operating temperature range (°C) -40 to 125 Iout/Iz (max) (mA) 15
SOT-23 (DBZ) 3 6.9204 mm² 2.92 x 2.37 X2SON (DQN) 4 1 mm² 1 x 1
  • Reference voltage tolerance at 25°C
    • 0.5% (B Grade)
    • 1% (A Grade)
  • Minimum typical output voltage: 2.5 V
  • Adjustable output voltage: Vref to 36 V
  • Operation from −40°C to +125°C (Q temp)
  • Maximum temperature drift
    • 17 mV (I Temp)
    • 27 mV (Q Temp)
  • 0.3-Ω Typical output impedance
  • Sink-current capability
    • Imin = 0.08 mA (max)
    • IKA = 15 mA (max)
  • Reference input current IREF: 0.4 µA (max)
  • Deviation of reference input current over temperature, II(dev): 0.3 µA (max)
  • Packages: 1-mm x 1-mm X2SON or SOT23-3
  • Reference voltage tolerance at 25°C
    • 0.5% (B Grade)
    • 1% (A Grade)
  • Minimum typical output voltage: 2.5 V
  • Adjustable output voltage: Vref to 36 V
  • Operation from −40°C to +125°C (Q temp)
  • Maximum temperature drift
    • 17 mV (I Temp)
    • 27 mV (Q Temp)
  • 0.3-Ω Typical output impedance
  • Sink-current capability
    • Imin = 0.08 mA (max)
    • IKA = 15 mA (max)
  • Reference input current IREF: 0.4 µA (max)
  • Deviation of reference input current over temperature, II(dev): 0.3 µA (max)
  • Packages: 1-mm x 1-mm X2SON or SOT23-3

The ATL43xLI device is a three-terminal adjustable shunt regulator, with specified thermal stability over applicable automotive, commercial, and military temperature ranges. The output voltage can be set to any value between Vref (approximately 2.5 V) and 36 V, with two external resistors. These devices have a typical output impedance of 0.3 Ω. Active output circuitry provides a very sharp turn-on characteristic, making these devices excellent replacements for Zener diodes in many applications, such as onboard regulation, adjustable power supplies, and switching power supplies. This device is a pin-to-pin alternative to the TL431LI and TL432LI, with lower minimum operating current to help reduce system power consumption. The ATL432LI device has exactly the same functionality and electrical specifications as the ATL431LI device, but has a different pinout for the DBZ package. The ATL431LI is also offered in a tiny X2SON (1.00 mm x 1.00 mm) package which makes it ideal for space constraint applications.

The ATL431LI device is offered in two grades, with initial tolerances (at 25°C) of 0.5%, and 1%, for the B and A grade, respectively. In addition, low output drift versus temperature ensures good stability over the entire temperature range.

The ATL43xLIxQ devices are characterized for operation from –40°C to +125°C.

The ATL43xLI device is a three-terminal adjustable shunt regulator, with specified thermal stability over applicable automotive, commercial, and military temperature ranges. The output voltage can be set to any value between Vref (approximately 2.5 V) and 36 V, with two external resistors. These devices have a typical output impedance of 0.3 Ω. Active output circuitry provides a very sharp turn-on characteristic, making these devices excellent replacements for Zener diodes in many applications, such as onboard regulation, adjustable power supplies, and switching power supplies. This device is a pin-to-pin alternative to the TL431LI and TL432LI, with lower minimum operating current to help reduce system power consumption. The ATL432LI device has exactly the same functionality and electrical specifications as the ATL431LI device, but has a different pinout for the DBZ package. The ATL431LI is also offered in a tiny X2SON (1.00 mm x 1.00 mm) package which makes it ideal for space constraint applications.

The ATL431LI device is offered in two grades, with initial tolerances (at 25°C) of 0.5%, and 1%, for the B and A grade, respectively. In addition, low output drift versus temperature ensures good stability over the entire temperature range.

The ATL43xLIxQ devices are characterized for operation from –40°C to +125°C.

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Technical documentation

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Type Title Date
* Data sheet ATL431LI / ATL432LI High Bandwidth Low-Iq Programmable Shunt Regulator datasheet (Rev. D) PDF | HTML 21 Nov 2019
Application note Optimization of a Shunt Reference for Flyback Converters PDF | HTML 18 Oct 2023
Application note Designing Stable Isolated Power Supplies with Shunt Regulators PDF | HTML 29 Dec 2022
Application note Shunt Regulator Design Procedures for Secondary Feedback Loop PDF | HTML 02 Feb 2021
Analog Design Journal High-power, low-cost, discrete linear pre-regulator for automotive rear lights 21 Dec 2020
Application note Precision Current Sources and Sinks Using Voltage References 30 Jun 2020
Technical article How modern voltage references help shrink small designs PDF | HTML 01 Jun 2020
Application note Extending the Input Voltage Range of the LM5180‐Q1 PSR Flyback for VDA320(LV148) 30 Jan 2020
Application note Using the TL431 for Undervoltage and Overvoltage Detection (Rev. A) 11 Dec 2019
Selection guide 431 Device Nomenclature (Rev. B) 18 Sep 2019
EVM User's guide ATL431LIEVM User's Guide 30 Aug 2019
E-book Voltage Supervisor and Reset ICs: Tips, Tricks and Basics 28 Jun 2019
Technical article Gain ultra-high power density for 100-W USB Power Delivery adapters PDF | HTML 05 Mar 2019
Application note Designing with the ATL431LI 27 Nov 2018

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Evaluation board

ATL431EVM-001 — ATL431 adjustable shunt regulator evaluation module

The ATL431EVM-001 evaluation module (EVM) features the functionality and adjustability of the ATL431 by letting you program the cathode voltage with various resistor values. You can also set the cathode current using the various resistors in series with the supply. (...)

User guide: PDF
Not available on TI.com
Evaluation board

ATL431LIEVM — ATL431LI high-bandwidth low-IQ programmable shunt regulator evaluation module for DQN package

The ATL431LI evaluation module (EVM) is an adjustable-voltage reference board that evaluates the ATL431LI device in the super-thin small-outline no-lead (X2SON) DQN small-form-factor package.

User guide: PDF
Not available on TI.com
Simulation model

ATL431LI PSpice Transient Model

SLVMCW7.ZIP (56 KB) - PSpice Model
Simulation model

ATL431LI Unencrypted PSpice Transient Model

SLVMCW6.ZIP (2 KB) - PSpice Model
Simulation model

TL431LI and ATL431LI PSpice Average Model

SLVMCX5.ZIP (78 KB) - PSpice Model
Simulation model

TL431LI and ATL431LI Unencrypted PSpice Average Model

SLVMCX4.ZIP (1 KB) - PSpice Model
Simulation tool

PSPICE-FOR-TI — PSpice® for TI design and simulation tool

PSpice® for TI is a design and simulation environment that helps evaluate functionality of analog circuits. This full-featured, design and simulation suite uses an analog analysis engine from Cadence®. Available at no cost, PSpice for TI includes one of the largest model libraries in the (...)
Reference designs

TIDA-01623 — 30-W/in3, 93.4% efficiency, 100-W AC/DC adapter reference design

This fully-tested reference design is a high-efficiency, high-power-density, AC/DC adapter solution with a wide input voltage range (100- to 240-V AC) for laptop adapters and smartphone charger applications. This design consists of a front-end transition-mode (TM) power factor correction (PFC) (...)
Design guide: PDF
Schematic: PDF
Reference designs

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This reference design is an industry-first digital hybrid hysteretic control (HHC) solution, targeting server PSU applications with 12-V to 54-V output. This reference design shows the HHC control advantages by UCD3138, in a 400-V to 12-V 1-kW LLC power stage. This design achieves 8-kHz peak loop (...)
Test report: PDF
Reference designs

PMP41081 — 1-kW, 12-V HHC LLC reference design using C2000™ real-time microcontroller

This reference design is a 1-kW, 400-V to 12-V half-bridge resonant DC/DC platform used to evaluate the load transient performance of hybrid-hysteretic control (HHC) with an F280039C microcontroller. HHC is a method which combines direct frequency control (DFC) and charge control, and is charge (...)
Test report: PDF
Reference designs

PMP31193 — Three-phase input valley switching flyback with two outputs reference design

This reference design uses the UCC28742 flyback controller to generate two outputs, 23 V @ 1.0 A and 5.0 V @ 0.15 A, from a three-phase input. UCC28742 uses an optical coupler to regulate the output and to improve transient response. The valley-switching technique reduces switching losses and (...)
Test report: PDF
Reference designs

PMP22396 — 2460-W bidirectional boost converter reference design for automotive applications

This reference design is a 2460-W bidirectional boost converter for automotive applications. The circuit is powered from the nominal 12-V battery to provide an output voltage of 48 V at 51.25 A. The design uses two dual-phase synchronous bidirectional controllers operating at a switching frequency (...)
Test report: PDF
Schematic: PDF
Reference designs

PMP30825 — 150-VDC - 430-VDC input, multiple output valley-switching flyback reference design

This 10-W non-isolated flyback reference design uses the UCC28742 controller to generate four outputs (5 V at 150 mA, 12 V at 690 mA, 15 V at 80 mA, 18 V at 20 mA). The controller provides constant-voltage and constant-current regulation. Transistors are used in place of an optocoupler feedback (...)
Test report: PDF
Schematic: PDF
Reference designs

PMP22151 — 70-W flyback and 37-W boost power reference design

This reference design uses two LM5155 devices to make a flyback and boost power stage. The flyback creates an isolated 28 Vdc bus from a 24 +/-10% Vdc bus and the boost creates a 37 Vdc bus from the output of the flyback. The flyback can be loaded up to 70 W and the boost can be loaded up to 37-W. (...)
Test report: PDF
Schematic: PDF
Reference designs

PMP30720 — High efficiency, ultra-wide input (20 VDC to 375 VDC) isolated power supply reference design

This reference design uses the UCC28C42 boost controller and the UCC28780 active-clamp flyback controller to generate an isolated output of 24 V at 3.5 A over an ultra-wide input voltage range of 20 V to 375 V. The design also uses the UCC24612 synchronous rectifier controller on the secondary (...)
Test report: PDF
Schematic: PDF
Reference designs

PMP22021 — Compact isolated DC/DC flyback reference design

This reference design uses LM5022-Q1 to make an isolated 3.3-V output capable of 1.1-A from a 9-V to 15-V input. All components are placed on one side of the board to reduce assembly complexity and cost. A secondary filter reduces the output ripple to under 30-mV peak-to-peak. The design can (...)
Test report: PDF
Schematic: PDF
Package Pins Download
SOT-23 (DBZ) 3 View options
X2SON (DQN) 4 View options

Ordering & quality

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Information included:
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