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Constant current source in SOT353 package

Resistor-equipped PNP transistor with two diodes on one chip in a SOT353 (SC-88A) plastic package. Stabilized output current of between 15 uA and 50 mA by connection of an external resistor between pins 4 and 5.

Orderable parts

Type number Orderable part number Ordering code (12NC) Package Buy from distributors
PSSI2021SAY PSSI2021SAY,115 934056564115 SOT353 Order product

Features and benefits

  • One chip integrated constant current source
  • Output current setting by use of an external resistor
  • Very small package
  • Reduces component count and board space
  • AEC-Q101 qualified


  • Automotive applications
  • Generic constant current source
  • Constant current LED driver
  • Active bias control for audio amplifiers


Type numberPackage versionPackage nameSize (mm)VSUP [max] (V)Limiting IO with external resistor [max] (mA)IO [max] (mA)Ptot [max] (mW)Polarity
PSSI2021SAYSOT353TSSOP52.1 x 1.25 x 0.9575500.02335PNP


Type numberOrderable part number, (Ordering code (12NC))StatusMarkingPackagePackage informationReflow-/Wave solderingPacking
( 9340 565 64115 )
Reel 7” Q1/T1 or Q2/T3

Quality, reliability & chemical content

Type numberOrderable part numberChemical contentRoHS / RHFMSLMSL leadfree
Quality and reliability disclaimer

Documentation (8)

File nameTitleTypeDate
PSSI2021SAYConstant current source in SOT353 packageData sheet2009-09-10
Nexperia_document_factsheet_LED_Driver_2020Constant current LED DriversLeaflet2020-08-18
Nexperia_document_factsheet_LED_Driver_2020_CHNLED Driver Factsheet CHNLeaflet2020-08-20
PSSI2021SAY_Nexperia_Product_QualityPSSI2021SAY Nexperia Product QualityQuality document2019-05-20
PSSI2021SAY_Nexperia_Product_ReliabilityPSSI2021SAY Nexperia Product ReliabilityQuality document2022-03-21
PSSI2021SAYPSSI2021SAY SPICE modelSPICE model2022-07-12
REFLOW_BG-BD-1Reflow soldering profileReflow soldering2021-04-06
WAVE_BG-BD-1Wave soldering profileWave soldering2021-09-08


If you are in need of design/technical support, let us know and fill in the answer form, we'll get back to you shortly.


File nameTitleTypeDate
PSSI2021SAYPSSI2021SAY SPICE modelSPICE model2022-07-12

Ordering, pricing & availability

Type numberOrderable part numberOrdering code (12NC)PackingPacking quantityBuy online
PSSI2021SAYPSSI2021SAY,115934056564115Reel 7” Q1/T1 or Q2/T3- Order product


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Sample orders normally take 2-4 days for delivery.

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