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LM431

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2%, 1%, or 0.5% accuracy, adjustable precision Zener shunt regulator

Data sheet
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2%, 1%, or 0.5% accuracy, adjustable precision Zener shunt regulator

LM431

ACTIVE
Data sheet Order now

Product details

Parameters

VO (V) 2.5 Reference voltage Adjustable Initial accuracy (Max) (%) 0.5, 1, 2 Rating Catalog VO adj (Min) (V) 2.5 VO adj (Max) (V) 36 Iz for regulation (Min) (uA) 400 Temp coeff (Max) (ppm/ degree C) 97 Operating temperature range (C) -40 to 85, 0 to 70 Iout/Iz (Max) (mA) 100 open-in-new Find other Shunt voltage references

Package | Pins | Size

SOIC (D) 8 19 mm² 4.9 x 3.9 SOT-23 (DBZ) 3 7 mm² 2.92 x 2.37 TO-92 (LP) 3 19 mm² 5.2 x 3.68 open-in-new Find other Shunt voltage references

Features

  • Average Temperature Coefficient 50 ppm/°C
  • Temperature Compensated for Operation Over
    the Full Temperature Range
  • Programmable Output Voltage
  • Fast Turnon Response
  • Low-Output Noise
  • Low-Dynamic Output Impedance
  • Available in Space-Saving SOIC-8, SOT-23, and
    TO-92 Packages
 open-in-new Find other Shunt voltage references

Description

The LM431 is a 3-terminal adjustable shunt regulator with ensured temperature stability over the entire temperature range of operation. The output voltage may be set at any level greater than 2.5 V (VREF) up to 36 V merely by selecting two external resistors that act as a voltage divided network. Due to the sharp turnon characteristics this device is an excellent replacement for many Zener diode applications.

The LM431 is available in space-saving SOIC-8, SOT-23, and TO-92 packages.

 open-in-new Find other Shunt voltage references
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Technical documentation

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Type Title Date
* Datasheet LM431 Adjustable Precision Zener Shunt Regulator datasheet (Rev. H) Jan. 06, 2016
Selection guides 431 Device Nomenclature (Rev. B) Sep. 18, 2019
More literature Voltage Supervisor and Reset ICs: Tips, Tricks and Basics Jun. 28, 2019
More literature Tips and tricks for designing with voltage references May 30, 2017
Application notes Low-cost flyback solutions for 10-mW standby power Jan. 22, 2014
Application notes AN-2102 LM3464 and LM5021 DHC 25W Reference Designs (Rev. A) May 01, 2013
Application notes Precision Output Current Limiting Using Average Current Monitor Feature Jun. 21, 2011
Application notes TO-92 Packing Options / Ordering Instructions (Rev. A) Jun. 23, 2010

Design & development

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

Design tools & simulation

SIMULATION MODELS Download
SNVMAB5A.ZIP (49 KB) - PSpice Model
CALCULATION TOOLS Download
Shunt voltage reference external resistor quick-start calculator
SHUNT_VOLTAGE_REFERENCE_RESISTOR_CALCULATOR — This external resistor quick-start calculator tool lets you easily calculate valid external resistor values relative to voltage reference, supply and load-current bounds. With these inputs, you can instantly view the resulting calculations and use the color-coded indications to understand (...)
Features
  • Case-specific tool to calculate external resistor value associated with shunt voltage reference
  • Input fields for: voltage reference, supply voltage, load current and Iq bound values
  • Real-time effects of input values on schematic
  • Quick indicators notifying user of valid and invalid outputs
  • Error messages (...)
View details

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PMP15012 — The PMP15012 reference design is a DC/DC buck-boost solution which accepts an input voltage of 18V to 36V and provides negative 15V/200mA output to the load. This reference design adds an external UVLO circuit to narrow the UVLO hysteresis because a buck-boost converter is difficult to shut down (...)
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PMP6024 — PMP6024 is an offline, LED driver circuit consisting of an isolated, power-factor corrected, constant output voltage flyback converter followed by two DC/DC buck LED current controllers.  It is suitable for indoor or outdoor area lighting applications of 3500-5000 lumens (depending upon LED (...)
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CAD/CAE symbols

Package Pins Download
SOIC (D) 8 View options
SOT-23 (DBZ) 3 View options
TO-92 (LP) 3 View options

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Videos

Voltage Reference Use Cases

Beyond the scope of signal chain conditioning, see other voltage reference use cases in this informative video.

Posted: 07-Jan-2018
Duration: 05:53

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