Discussion Overview
The discussion revolves around issues encountered while simulating the LTC4440 high side MOSFET driver in LTSpice. Participants are exploring the functionality of the driver, particularly its ability to boost gate control voltage for driving MOSFETs under specified conditions.
Discussion Character
- Technical explanation
- Debate/contested
- Experimental/applied
Main Points Raised
- One participant reports that the LTC4440 does not seem to provide the necessary boost to the gate control in their LTSpice simulation, raising concerns about its ability to drive a MOSFET with a specified drain voltage of 70V.
- Another participant points out that the original poster may have forgotten to attach the relevant schematic for further analysis.
- A later reply suggests that the boost section of the circuit was not connected correctly and advises checking the datasheet for proper connections, specifically mentioning the need for a diode.
- Another participant shares that they were able to get the circuit working after adding the diode and changing the MOSFET model to one from the library, indicating that the default model may not have been suitable.
- This participant also notes that the LTC4440 is capable of driving a 1nF load with specific rise and fall times, as stated in the datasheet, and recommends extending the simulation time to observe steady-state behavior.
- Concerns are raised about potential unexpected behavior in the simulation depending on load resistance and MOSFET model used.
Areas of Agreement / Disagreement
There is no clear consensus on the issues faced with the LTC4440 simulation, as participants present differing views on the circuit configuration and component selection. Multiple competing approaches to resolving the simulation problems are discussed.
Contextual Notes
Limitations include potential missing assumptions regarding circuit connections and component models, as well as unresolved questions about the simulation parameters and their impact on results.
