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DC1471A - LT3990EMSE Demo Board | 6.5V ≤ VIN ≤ 60V, VOUT = 5V @ 350mA, Integrated Diodes

Demonstration circuit 1471 is a monolithic stepdown DC/DC switching regulator featuring the LT3990. The switching frequency is adjustable up to 2.2MHz. The demo circuit is designed for 5V, 350mA output from a 6.5V to 62V input. The wide input range of the LT3990 allows a variety of input sources including automotive batteries and 24V industrial supplies. Low ripple Burst Mode increases the efficiency at the light load while keeping the output ripple below 5mV in a typical application. The part is in shutdown when the EN pin is low and active when the pin is high. The threshold of the EN pin is accurate at 1V when Vin is above 4.2V. Adding a resistor divider from Vin to EN can program the LT3990 to regulate the output only when Vin is above a desired voltage. The catch diode and boost diode are integrated to reduce the components count and solution size. The circuit consumes only 2.5μA of quiescent current.

DC1471A - Schematic

 


Software

LTspice

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:

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

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