Datasheet Linear Technology LTC3854EMSE#PBF

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  Step-Down DC/DC Controller in 2mm × 3mm DFN Includes FET Drivers, DCR Sensing and Accepts Inputs to 38V &mdash LT Journal
  PDF, 901 Kb, File published: Jul 15, 2011
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  Step-Down DC/DC Controller in 2mm Г— 3mm DFN Includes
  FET Drivers, DCR Sensing and Accepts Inputs to 38V
  Mike Shriver Wide input voltage range and reliability are desirable features in any buck converter. The
  LTC3854 delivers these features and more in a 2mm Г— 3mm DFN or MSE package.
  This current mode controller with integrated N-channel FET gate drivers can produce
  output voltages ranging from 0.8V to 5.5V over an input voltage range of 4.5V to 38V.
  SENSING THE CURRENT The LTC3854 employs a fixed frequency
  peak current mode topology, which
  provides a cycle-by-cycle current limit.
  Current can be sensed with discrete
  sense resistors in series with the inductor. Alternately, the DC resistance of
  the inductor (DCR) can be used to sense
  current instead of a sense resistor by
  placing an RC filter across the inductor
  to recreate the triangular current sense waveform. The advantage of DCR sensing is improved efficiency (thanks to the
  elimination of the power losses of the
  sense resistor), lower parts count and
  lower cost. The disadvantage is a less
  accurate current limit due to DCR variations part-to-part and over temperature. but with DCR sensing. The full load efficiency of the circuit with a sense resistor
  is 86.9%, while the full load efficiency
  increases to 88.7% (see Figure 3) with
  DCR sensing. The 400kHz switching frequency provides a good balance between
  high efficiency on one hand and a fast …

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Manufacturer's Classification

• Power Management > Switching Regulator > Step-Down (Buck) Regulators > External Power Switch Buck Controllers

Other Names:

LTC3854EMSEPBF, LTC3854EMSE PBF