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How to calculate value of the MOSFET input resistor?
Following is the application diagram of the module. Basically this is the GATE driver circuit for the MOSFET with PDM signal as the input. I am looking for how to calculate value of the MOSFET input resistor (R3) ?
How to calculate the gate resistor value ( R3 )?
This is the datasheet of the driver IC I am working on (LM5112). Following is the application diagram of the module. Basically this is the GATE driver circuit for the MOSFET with PDM signal as the input. I am looking for how to calculate value of the MOSFET input resistor (R3) ?
Is it possible to use two gate resistors?
NOTE: It is possible to use two gate resistors, with associated diodes if the source and sink limits are different in the driver, or a need be to sharpen either the turn on or turn off edges. Ok, so now perhaps you can see why the gate resistor is important.
How can I reduce the voltage of MOSFET?
Slow down the switching to reduce EMI. But in this case you may as well use a weaker (cheaper) driver. Reduce the current spike drawn from the supply during MOSFET turn-on. If local decoupling is not good enough, this current could make VCC sag, triggering the chip’s UVLO.
Which is the DC equivalent of the MOSFET circuit?
Below is the schematic of the DC equivalent of the mosfet circuit above: Now let’s do the calculations for DC analysis. Vgs is the voltage that falls across the gate and the source of the mosfet transistor. It is crucial to calculate because in order to solve for Ids, the current from the drain to the source, Vgs must be known.
Is the NCH MOSFET a linear voltage controlled resistor?
Here a Nch MOSFET is shown with some arbitrary Drain current for Vgs above Vth on the x axis. and thus is a linear voltage controlled resistor until that resistance curve saturates or flattens out. Rds will pull down the 240 Ohms by the some unknown amount based on the rated RdsOn @Vgs=6V If RdsOn was 10 Ohms Vd= 0.5V