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SY21401DBC (SY7901DBC)

Production

The SY21401 is a current mode DC/DC controller targeted for Boost, SEPIC, Flyback and Forward applications. The SY21401 has an accurate DC input current limit. External compensation provides flexible adjustment of control loops for different applications. The internal low side driver is capable of sourcing 1.5A and sinking 3A current.

Datasheet
SY21401DBC The SY21401 is a current mode DC/DC controller targeted for Boost, SEPIC, Flyback and Forward applications. The SY21401 has an accurate DC input current limit. External compensation provides flexible adjustment of control loops for different applications. The internal low side driver is capable of sourcing 1.5A and sinking 3A current. Datasheet
Part number SY21401DBC
Channel(#) 1
Vin (min) (V) 3
Vin (max) (V) 25
Topology Boost,SEPIC,Flyback,Forward
Switching frequency (min)(kHz) 500
Switching frequency (max)(kHz) 500
Vout (min) (V) 3
Vout2 (min)(V)
Vout (max) (V) Programmable
Vout2 (max )(V)
Vref accuracy (±%) 2
Vout accuracy(±%)
Control mode Peak current mode
Duty cycle (max)(%) 85
Operation mode PFM
Iq (typ) (uA) 170
Features Soft start,Input current limit
Package DFN3x3-10
Operating temperature range(°C) -40 to 125
Functional safety category

 

  • Input Voltage Range 3V to 25V
  • 500kHz Fixed Switching Frequency
  • An Accurate DC Input Current Limit
  • External Compensation
  • Internal Soft-start Limits the Inrush Current
  • Integrated Low Side Driver:1.5ASourcing and3ASinking
  • RoHS Compliant and Halogen Free
  • Compact Package: DFN3×3-10

 

The SY21401 is a current mode DC/DC controller targeted for Boost, Sepic, Flyback and Forward applications. The SY21401 has an accurate DC input current limit. External compensation provides flexible adjustment of control loops for different applications. The internal low side driver is capable of sourcing 1.5A and sinking 3A current.

Evaluation Board

  • 21401-11

    Photo of evaluation board

  • 21401-12

    Photo of evaluation board

  • 21401-13

    Photo of evaluation board

EVB_SY21401DBC_1

The EVB_SY21401DBC_1 is intended for evaluating 6~18V input, 4A input current limit, 12V output SEPIC applications.

  • 21401-21

    Photo of evaluation board

  • 21401-22

    Photo of evaluation board

  • 21401-23

    Photo of evaluation board

EVB_SY21401DBC_2

The EVB_SY21401DBC_2 is intended for evaluating 6~8.4V input, 2A output current, 12V output Boost applications.

Technical Documentation

Title Date
Silergy_Catalog_Q2_2026 2026-06-12
DFN3x3-10 2022-05-20