1. Skip to navigation
  2. Skip to content
  3. Skip to sidebar

DC2354A - LTC7149 Demo Board | Buck Configured as Negative VOUT; 3.5V ≤ VIN ≤ 55V; Vout = -3.3V/-5V/Adj to -56V @ Up to 4A

Demonstration circuit 2354A is a high input voltage, high efficiency synchronous monolithic step-down converter with a negative output voltage featuring the LTC7149. DC2354A has a wide input voltage range from 3.5V up to 55V. The output voltage of the DC2354A can be set  to –3.3V or –5V, and the “User Select” option allows the output voltage to be set from 0V to –60V; however the voltage difference between the output voltage (–VOUT) and maximum input voltage (VIN), should not exceed 60V. |–VOUT| + VIN < 60V. DC2354A is capable of delivering up to 4A of output current, nevertheless at lower input voltages, the load current should be reduced in accordance with the derating curves. DC2354A supports three operation modes: fixed-frequency modulation, Burst Mode™ operation and synchronization to an external clock. Fixed-frequency mode maximizes the output current, reduces output voltage ripple, and yields a low noise switching spectrum. Burst Mode operation employs a variable frequency switching algorithm that minimizes the no-load input quiescent current and improves efficiency at light loads.

DC2354A - Schematic




LTspice® software is a powerful, fast and free simulation tool, schematic capture and waveform viewer with enhancements and models for improving the simulation of switching regulators. Click here to download LTspice

To launch a ready to run LTspice demonstration circuit for this part:

To explore other ready to run LTspice demonstration circuits, please visit our Demo Circuits Collection.


The LTpowerCAD design tool is a complete power supply design tool program that can significantly ease the tasks of power supply design. It guides users to a solution, selects power stage components, provides detailed power efficiency, shows quick loop bode plot stability and load transient analysis, and can export a final design to LTspice for simulation. Click here to download LTpowerCAD

To open the project file for this circuit:

  • Step 1: If you have not installed LTpowerCAD on this computer, download and install LTpowerCAD
  • Step 2: Once LTpowerCAD is installed, click on the link(s) below to open the project file
  • Step 3: If LTpowerCAD does not automatically open after clicking the link above, you can open the project file by right clicking on the link and selecting "Save Target As." After saving the file to your computer, start LTpowerCAD and open the project file by selecting 'Open Project' from the 'File' menu