DC2148A - LT8709EFE Demo Board | Negative Buck-Boost, -38V ≤ VIN ≤ -4.5V; VOUT = -12V @ 5A

Demonstration circuit 2148A features the LT®8709, a negative input synchronous multi-topology DC/DC controller designed for negative input power supplies where the highest input supply voltage is ground. Examples of these circuits include negative buck, negative boost, negative buck-boost and negative inverting. The DC2148A is a negative buck-boost with an operating input voltage range from –4.5V to –38V and an output voltage of –12V, however this demo circuit can be easily reconfigured for other negative input topologies. The maximum output current for DC2148A is 5A, the switching frequency is 400kHz and the maximum efficiency with a –12V input is 91%.

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
- LT8709 Demo Circuit - Negative Buck-Boost Regulator with Output Current Monitor & Power Good (-4.5V to -38Vin to -12Vout @ 5A)
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.