Datasheet Linear Technology LT3845

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  A Positive-to-Negative Voltage Converter Can Be Used for Stable Outputs Even with a Widely Varying Input &mdash DN433
  PDF, 102 Kb, File published: Dec 10, 2007
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  advertisement A Positive-to-Negative Voltage Converter Can Be Used for
  Stable Outputs Even with a Widely Varying Input – Design Note 433
  Victor Khasiev +
  – , LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
  All other trademarks are the property of their respective owners.
  01/08/433 Q PWM D VO– +
  C L RLOAD
  DN433 F01 Figure 1. Simplifed Block Diagram of
  Positive-to-Negative Converter
  VIN+ +
  – V1 D VO– +
  – V1 Q D VO– +
  L C RLOAD L + C RLOAD
  DN433 F02 (2a) Transistor Q is On (2b) Transistor Q is Off Figure 2. Equivalent Circuits Show the Operation
  of the Positive-to-Negative Converter
  Q GATE ON OFF ON OFF IL A new generation of Linear Technology high voltage synchronous step-down converters, such as the LTВ®3845,
  make it possible to implement positive-to-negative
  conversions for a variety of applications.
  Basic Operation
  Figure 1 shows a simplified block diagram of a positive-tonegative converter. Figure 2 shows an equivalent circuit,
  which helps in understanding the basic operation of the
  circuit in Figure 1. When transistor Q is on (Figure 2a),
  diode D is reverse biased and the current in inductor L …

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Manufacturer's Classification

• Power Management > Switching Regulator > Step-Down (Buck) Regulators > High Input Voltage Buck | External Power Switch Buck Controllers
• Space & Harsh Environment > Extended Temperature Plastic (H & MP) > Extended Temperature (H & MP) Switching Regulators