LT1431 - Programmable Reference


  • Guaranteed 0.4% Initial Voltage Tolerance
  • 0.1Ω Typical Dynamic Output Impedance
  • Fast Turn-On
  • Sink Current Capability, 1mA to 100mA
  • Low Reference Pin Current
  • Available in J8, N8, S8 or 3-Lead TO-92 Z Packages

Typical Application

LT1431 Typical Application
LT1431 Typical Application


The LT1431 is an adjustable shunt voltage regulator with 100mA sink capability, 0.4% initial reference voltage tolerance and 0.3% typical temperature stability. On-chip divider resistors allow the LT1431 to be configured as a 5V shunt regulator, with 1% initial voltage tolerance and requiring no additional external components. By adding two external resistors, the output voltage may be set to any value between 2.5V and 36V. The nominal internal current limit of 100mA may be decreased by including one external resistor.

A simplified 3-pin version, the LT1431CZ/LT1431IZ, is available for applications as an adjustable reference and is pin compatible with the TL431.


CAD Symbols and Footprints: The downloadable Zip file below contains the schematic symbol and PCB footprints.

For complete and up to date package information and drawings, please refer to our packaging page

Part Number Package Code Temp Package
LT1431CN8#PBF N-8 N C 05-08-1510 (N8) Yes
LT1431CS8#PBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1431CS8#TRPBF SO-8 S8 C 05-08-1610 (S8) Yes
LT1431CZ#PBF TO-92 Z C 05-08-1410 Yes
LT1431CZ#TRPBF TO-92 Z C 05-08-1410 Yes
LT1431IN8#PBF N-8 N I 05-08-1510 (N8) Yes
LT1431IS8#PBF SO-8 S8 I 05-08-1610 (S8) Yes
LT1431IS8#TRPBF SO-8 S8 I 05-08-1610 (S8) Yes
LT1431IZ#PBF TO-92 Z I 05-08-1410 Yes
LT1431IZ#TRPBF TO-92 Z I 05-08-1410 Yes
LT1431MPS8#PBF SO-8 S8 MP 05-08-1610 (S8) Yes
LT1431MPS8#TR SO-8 S8 MP 05-08-1610 (S8) No
LT1431MPS8#TRPBF SO-8 S8 MP 05-08-1610 (S8) Yes

LT1431 Package Drawing
LT1431 Package Drawing
LT1431 Package Drawing
LT1431 Package Drawing

Order Info

  • Part numbers ending in PBF are lead free. Solder plated terminal finish (SnPb) versions are non-standard and special terms and conditions and pricing applies if available. Please contact LTC marketing for information.
  • Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
  • Please refer to our general ordering information or the product datasheet for more details

Package Variations and Pricing

Part Number Package Temp Price
LT1431CN8#PBF N-8 C $1.50 $1.20 Yes
LT1431CS8#PBF SO-8 C $2.08 $1.75 Yes
LT1431CS8#TRPBF SO-8 C $1.81 Yes
LT1431CZ#PBF TO-92 C $1.35 $1.05 Yes
LT1431CZ#TRPBF TO-92 C $1.11 Yes
LT1431IN8#PBF N-8 I $1.92 $1.55 Yes
LT1431IS8#PBF SO-8 I $2.67 $2.20 Yes
LT1431IS8#TRPBF SO-8 I $2.26 Yes
LT1431IZ#PBF TO-92 I $1.42 $1.11 Yes
LT1431IZ#TRPBF TO-92 I $1.17 Yes
LT1431MPS8#PBF SO-8 MP $9.27 $6.49 Yes
LT1431MPS8#TR SO-8 MP $6.55 No
LT1431MPS8#TRPBF SO-8 MP $6.55 Yes
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* The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Linear Technology sales office or authorized distributor.

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.

Part Number Description Price Documentation
DC259A LT1339, LTC1693, LT1431 Isolated Demo Board | Telecom Module, 36 to 72Vin, 5V or 3.3Vout @ 10A Contact Factory
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  • Linear Regulators
  • Adjustable Power Supplies
  • Switching Power Supplies

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