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3 A DC step-down switching regulator

Quantity $ per Unit Savings
1 - 9$2.640%
10 - 24$2.3810%
25 - 99$2.2415%
100 - 230$1.9128%
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Parameter NameParameter Value
Input Voltage Min Volt4.0
Input Voltage Max Volt18.0
Packing TypeTape And Reel
RoHs compliantEcopack2
Package NamePowerSO-8

The ST1S40 is an internally compensated 850 kHz fixed-frequency PWM synchronous step-down regulator. ST1S40 operates from 4.0 V to 18 V input, while it regulates an output voltage as low as 0.8 V and up to VIN.

The ST1S40 integrates a 95 mΩ high side switch and 69 mΩ synchronous rectifier allowing very high efficiency with very low output voltages.

The peak current mode control with internal compensation delivers a very compact solution with a minimum component count.

The ST1S40 is available in VFQFPN 4 mm x 4 mm 8 lead package, HSOP-8 and standard SO-8 package.

Key features
  • 3 A DC output current
  • 4.0 V to 18 V input voltage
  • Output voltage adjustable from 0.8 V
  • 850 kHz switching frequency
  • Internal soft-start
  • Integrated 95 mΩ and 69 mΩ Power MOSFETs
  • All ceramic capacitor
  • Enable
  • Cycle-by-cycle current limiting
  • Current fold back short-circuit protection
  • VFQFPN4x4-8L, HSOP-8, and SO-8 and packages