An internally adjusted 850 kHz fixed-frequency PWM synchronous stepdown regulator is the ST1S40 device. The ST1S40 controls an output voltage as low as 0.8 V and as high as VIN while operating with an input range of 4.0 V to 18 V.

The ST1S40 incorporates a 69 m synchronous rectifier with a 95 m high side switch, enabling extremely high efficiency at very low output voltages.

A very small solution with a low component count is delivered by the peak current mode control with internal compensation. The ST1S40 comes in three different packages: HSOP-8, VFQFPN 4 mm x 4 mm - 8 lead, and conventional SO8.

• 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 m? and 69 m? Power MOSFETs

  
  

• All ceramic capacitor

  
  

• Enable

  
  

• Cycle-by-cycle current limiting

  
  

• Current fold back short-circuit protection

  
  

• Available in HSOP-8, VFQFPN4x4-8L, and SO8 packages

  
  

  
  

  
  

  ST1S40IDR Applications

  
  

  • P/ASIC/DSP/FPGA core and I/O supplies

    
    

  • Point of load for: STB, TVs, DVD

    
    

  • Optical storage, hard disk drive, printers, audio/graphic cards

    
    

    
    

    Lifecycle Status	ACTIVE (Last Updated: 7 months ago)
    Factory Lead Time	10 Weeks
    Contact Plating	Gold
    Mount	Surface Mount
    Mounting Type	Surface Mount
    Package / Case	8-SOIC (0.154, 3.90mm Width)
    Number of Pins	8
    Manufacturer Package Identifier	SO8-BW-0016023C
    Operating Temperature	-40°C~150°C TJ
    Packaging	Tape & Reel (TR)
    JESD-609 Code	e4
    Part Status	Active
    Moisture Sensitivity Level (MSL)	1 (Unlimited)
    Number of Terminations	8
    ECCN Code	EAR99
    Max Power Dissipation	1.6W
    Terminal Position	DUAL
    Terminal Form	GULL WING
    Base Part Number	ST1S40
    Function	Step-Down
    Number of Outputs	1
    Output Voltage	18V
    Output Type	Adjustable
    Max Output Current	4A
    Operating Supply Voltage	18V
    Max Supply Voltage	18V
    Min Supply Voltage	4V
    Analog IC - Other Type	SWITCHING REGULATOR
    Nominal Supply Current	1.5mA
    Output Configuration	Positive
    Current - Output	3A
    Max Output Voltage	18V
    Voltage - Output (Min/Fixed)	0.8V
    Topology	Buck
    Control Mode	CURRENT-MODE
    Frequency - Switching	850kHz
    Control Technique	PULSE WIDTH MODULATION
    Synchronous Rectifier	Yes
    Min Output Voltage	800mV
    Max Duty Cycle	100 %
    Max Junction Temperature (Tj)	150°C
    Height	1.75mm
    Length	4.9mm
    Width	3.9mm
    Radiation Hardening	No
    RoHS Status	ROHS3 Compliant
    Lead Free	Lead Free